The heart is a muscular organ that acts as a pump to circulate blood through the body. It has four chambers separated by valves that ensure one-way blood flow. The right side receives deoxygenated blood and pumps it to the lungs, while the left side receives oxygenated blood and pumps it out to the body. The heart muscle requires its own blood supply which is provided by the coronary arteries.
The cardiac cycle describes the repeating sequence of heart contraction and relaxation that pumps blood throughout the body. It has two main phases: diastole, where the heart relaxes and fills with blood, and systole, where the heart contracts to pump out blood. Specifically, it involves atrial diastole, atrial systole, ventricular diastole, and ventricular systole. The cardiac cycle ensures blood is continuously circulating at a rate of around 72 beats per minute, pumping approximately 5-6 liters of blood per minute known as cardiac output through the coordinated squeezing of the heart's left and right ventricles.
The document discusses conduits used in coronary artery bypass grafting (CABG). It describes the history of CABG, beginning with Alexis Carrel's description in the early 1900s. It outlines the three eras of CABG and discusses key pioneers like Michael DeBakey and Rene Favaloro. The document then describes the different types of arterial and venous conduits used in CABG, focusing on the internal thoracic artery and radial artery. It discusses the anatomy, histology, harvesting techniques, and patency rates of different conduits.
The document summarizes the cardiac cycle and related events. It describes:
1) Atrial pressure changes including a, c, and v waves that occur during atrial systole and ventricular contraction and filling.
2) The relationship between the ECG and cardiac cycle, with the P wave occurring during atrial depolarization, the QRS complex starting ventricular contraction, and the T wave coinciding with ventricular relaxation.
3) The timing of events in the right and left sides of the heart, with right atrial contraction preceding left atrial contraction and right ventricular ejection beginning before left ventricular ejection.
4) Key metrics like end diastolic volume, stroke volume, end systolic volume
The document summarizes the structure and anatomy of the heart. It describes the location and orientation of the heart in the thoracic cavity. It then discusses the layers that cover the heart, including the fibrous and serous pericardium. It provides details on the chambers of the heart, including the right and left atria and ventricles. It also describes the valves of the heart, including the tricuspid, bicuspid, pulmonary, and aortic valves. Finally, it summarizes the coronary arteries that supply blood to the heart muscle and the veins that drain blood from it.
Cardiac Measurements Guidelines | powered by EsaoteMIDEAS
Complete routine cardiac measurements Guidelines.
1) Left Ventricle:
a) Size: Dimensions or volumes, at end-systole and end-diastole
b) Wall thickness and/or mass: Ventricular septum and left ventricular posterior wall thicknesses (at end-systole and end-diastole) and/or mass (at end-diastole)
c) Function: Assessment of systolic function and regional wall motion. Assessment
of diastolic function
2) Left Atrium:
• Size: Area or dimension
3) Aortic Root:
• Dimension
4) Right Ventricle:
Size: Dimensions
Function: Systolic and diastolic function
RV & pulmonary hemodynamics
5) Right Atrium:
a) Size: Dimensions, area
b) RA pressure
6) Valvular Stenosis:
a) Valvular Stenosis: Assessment of severity, including trans-valvular gradient and area.
b) Subvalvular Stenosis: Assessment of severity, Including subvalvular gradient.
7) Valvular Regurgitation: Assessment of severity with semi-quantitative descriptive statements and/or quantitative measurements
8) Cardiac Shunts: Assessment of severity. Measurements of QP:QS (pulmonary-to systemic flow ratio) and/or orifice area or diameter of the defect are often helpful.
9) Prosthetic Valves:
a) Transvalvular gradient and effective orifice area
b) Description of regurgitation, if present
This document summarizes various cardiac pathologies. It discusses problems related to inadequate cardiac output such as leaks in the cardiovascular system, irregular heart rhythms, obstructions to blood flow, and valve problems. Congenital heart diseases are also examined, noting they result from mixing of oxygenated and unoxygenated blood and can be caused by genetic or environmental factors like infections. Specific congenital defects like atrial septal defects and tetralogy of Fallot are described. Other cardiac conditions reviewed include ischemic heart disease, hypertension, cardiomyopathy, pericardial diseases, infective endocarditis, and rheumatic fever.
The conduction system of the heart is initiated by the sinoatrial node, which acts as the dominant pacemaker. It is located in the junction of the right atrium and superior vena cava and is innervated by the parasympathetic and sympathetic nervous systems. Conduction then proceeds through the atrioventricular node, which slows conduction to allow for ventricular filling, and the bundle of His divides into left and right bundle branches to stimulate the ventricles.
Useful for medical and biology students who want to study the cardiac cycle in a short time with big benefits !!
CVS physiology - Wigger Diagram - ECG of cardiac cycle - Heart sounds
The cardiac cycle describes the repeating sequence of heart contraction and relaxation that pumps blood throughout the body. It has two main phases: diastole, where the heart relaxes and fills with blood, and systole, where the heart contracts to pump out blood. Specifically, it involves atrial diastole, atrial systole, ventricular diastole, and ventricular systole. The cardiac cycle ensures blood is continuously circulating at a rate of around 72 beats per minute, pumping approximately 5-6 liters of blood per minute known as cardiac output through the coordinated squeezing of the heart's left and right ventricles.
The document discusses conduits used in coronary artery bypass grafting (CABG). It describes the history of CABG, beginning with Alexis Carrel's description in the early 1900s. It outlines the three eras of CABG and discusses key pioneers like Michael DeBakey and Rene Favaloro. The document then describes the different types of arterial and venous conduits used in CABG, focusing on the internal thoracic artery and radial artery. It discusses the anatomy, histology, harvesting techniques, and patency rates of different conduits.
The document summarizes the cardiac cycle and related events. It describes:
1) Atrial pressure changes including a, c, and v waves that occur during atrial systole and ventricular contraction and filling.
2) The relationship between the ECG and cardiac cycle, with the P wave occurring during atrial depolarization, the QRS complex starting ventricular contraction, and the T wave coinciding with ventricular relaxation.
3) The timing of events in the right and left sides of the heart, with right atrial contraction preceding left atrial contraction and right ventricular ejection beginning before left ventricular ejection.
4) Key metrics like end diastolic volume, stroke volume, end systolic volume
The document summarizes the structure and anatomy of the heart. It describes the location and orientation of the heart in the thoracic cavity. It then discusses the layers that cover the heart, including the fibrous and serous pericardium. It provides details on the chambers of the heart, including the right and left atria and ventricles. It also describes the valves of the heart, including the tricuspid, bicuspid, pulmonary, and aortic valves. Finally, it summarizes the coronary arteries that supply blood to the heart muscle and the veins that drain blood from it.
Cardiac Measurements Guidelines | powered by EsaoteMIDEAS
Complete routine cardiac measurements Guidelines.
1) Left Ventricle:
a) Size: Dimensions or volumes, at end-systole and end-diastole
b) Wall thickness and/or mass: Ventricular septum and left ventricular posterior wall thicknesses (at end-systole and end-diastole) and/or mass (at end-diastole)
c) Function: Assessment of systolic function and regional wall motion. Assessment
of diastolic function
2) Left Atrium:
• Size: Area or dimension
3) Aortic Root:
• Dimension
4) Right Ventricle:
Size: Dimensions
Function: Systolic and diastolic function
RV & pulmonary hemodynamics
5) Right Atrium:
a) Size: Dimensions, area
b) RA pressure
6) Valvular Stenosis:
a) Valvular Stenosis: Assessment of severity, including trans-valvular gradient and area.
b) Subvalvular Stenosis: Assessment of severity, Including subvalvular gradient.
7) Valvular Regurgitation: Assessment of severity with semi-quantitative descriptive statements and/or quantitative measurements
8) Cardiac Shunts: Assessment of severity. Measurements of QP:QS (pulmonary-to systemic flow ratio) and/or orifice area or diameter of the defect are often helpful.
9) Prosthetic Valves:
a) Transvalvular gradient and effective orifice area
b) Description of regurgitation, if present
This document summarizes various cardiac pathologies. It discusses problems related to inadequate cardiac output such as leaks in the cardiovascular system, irregular heart rhythms, obstructions to blood flow, and valve problems. Congenital heart diseases are also examined, noting they result from mixing of oxygenated and unoxygenated blood and can be caused by genetic or environmental factors like infections. Specific congenital defects like atrial septal defects and tetralogy of Fallot are described. Other cardiac conditions reviewed include ischemic heart disease, hypertension, cardiomyopathy, pericardial diseases, infective endocarditis, and rheumatic fever.
The conduction system of the heart is initiated by the sinoatrial node, which acts as the dominant pacemaker. It is located in the junction of the right atrium and superior vena cava and is innervated by the parasympathetic and sympathetic nervous systems. Conduction then proceeds through the atrioventricular node, which slows conduction to allow for ventricular filling, and the bundle of His divides into left and right bundle branches to stimulate the ventricles.
Useful for medical and biology students who want to study the cardiac cycle in a short time with big benefits !!
CVS physiology - Wigger Diagram - ECG of cardiac cycle - Heart sounds
The cardiovascular system includes the heart and blood vessels. The heart weighs 200-400 grams and pumps around 7,751 litres of blood daily. It is located behind the sternum and is surrounded by membranes. Blood enters and exits the heart through major vessels while valves regulate flow between chambers. The heart muscle generates electrical impulses and contractions to circulate blood throughout the body. Cardiac output is regulated intrinsically through preload and afterload as well as extrinsically through the nervous and endocrine systems.
The document discusses the valves of the heart. There are two types of valves - atrioventricular valves and semilunar valves.
The atrioventricular valves include the tricuspid valve between the right atrium and ventricle, and the mitral/bicuspid valve between the left atrium and ventricle.
The semilunar valves include the pulmonary valve between the right ventricle and pulmonary artery, and the aortic valve between the left ventricle and aorta. Each valve has specific roles in regulating blood flow and preventing backflow through the heart chambers and vessels.
The coronary circulation refers to the blood vessels that supply and drain the heart. The heart receives its blood supply from two coronary arteries - the left and right coronary arteries. The left coronary artery supplies the left side of the heart including parts of the left atrium and ventricle. It branches into the anterior interventricular artery and circumflex artery. The right coronary artery supplies the right side of the heart and parts of the left side. It has branches like the right marginal artery and posterior interventricular artery. Deoxygenated blood from the heart drains into the coronary sinus and other cardiac veins before emptying into the right atrium.
This document provides an overview of the physiology of the cardiovascular system. It begins with an introduction and outlines the components and general functions of the CVS. It then discusses the anatomy of the heart, including its chambers and valves. It describes the pathway of blood flow through the heart and lungs. It explains cardiac muscle and the cardiac conduction system, including the sinoatrial node, atrioventricular node, bundle of His, and Purkinje fibers. It concludes with a discussion of the action potential in pacemaker cells and contractile cells in the heart.
The document summarizes the valves of the heart, including their structure, location, and function. There are two pairs of valves: atrioventricular valves (tricuspid and bicuspid/mitral) which allow blood to flow from the atria to the ventricles, and semilunar valves (pulmonary and aortic) which allow blood to exit the ventricles. The valves have cusps that open and close to ensure one-way blood flow and prevent backflow. Issues like stenosis can cause murmurs and increase pressures on the respective chambers of the heart.
The aortic valve has three leaflets (cusps) and is located between the left ventricle and the ascending aorta. It has important relationships with surrounding structures like the mitral valve, ventricular septum, and conduction bundles. The leaflets are attached to fibrous structures like the annulus, sinuses of Valsalva, and sinotubular junction. On echocardiogram, the aortic valve can be seen opening and closing from the parasternal long and short axis views. The document provides details on the anatomy, embryology, histology, and imaging of the aortic valve.
The document discusses factors that regulate cardiac output, including preload, contractility, and afterload. It describes how the respiratory pump, cardiac pump, muscle pump, and mean circulatory filling pressure affect cardiac output by changing preload. Sympathetic stimulation and hormones are discussed as factors increasing contractility. Methods for measuring cardiac output are also summarized, including the Fick principle, indicator dilution, thermodilution, Doppler echocardiography, and impedance cardiography. Cardiac output is increased in conditions like fever and anemia that cause increased metabolism, and decreased in states of weak contractions or poor pumping like congestive heart failure.
The coronary arteries arise from the ascending aorta and form a circulatory loop around the heart. The right coronary artery originates from the right sinus and supplies the right atrium and ventricle. The left coronary artery originates from the left sinus and divides into the left anterior descending artery and circumflex artery to supply the left side of the heart. Blood from the heart drains primarily into the coronary sinus which empties into the right atrium.
The right and left coronary arteries originate from the right and left sinuses of the aortic root. The right coronary artery supplies the right ventricle while the left coronary artery supplies the anterior portion of the ventricular septum and left ventricle. The left main coronary artery bifurcates into the left anterior descending artery and left circumflex artery. The left anterior descending artery supplies the majority of the left ventricle while the left circumflex artery supplies the left ventricle free wall. In approximately 70% of cases, the right coronary artery is the dominant artery supplying the posterior portions of the heart.
The cardiac cycle describes the sequence of events in one heartbeat. It involves systole, the contraction of the ventricles, and diastole, the relaxation of the ventricles. During atrial systole, the atria contract and blood passes to the relaxed ventricles. During ventricular systole, the ventricle walls contract and force blood out through the arteries. During diastole, the ventricles relax and blood flows back into the atria from the veins, completing the cycle.
Internal feature of right and left atriafarranajwa
This document provides information about the anatomy and structures of the right and left atria of the heart. It discusses the key internal features of each atrium, including chambers, valves, veins and arteries, muscle structures, and other anatomical landmarks. It also briefly explains some clinical significance of atrial structures, mentioning how abnormalities like atrial septal defects or atrial fibrillation can impact blood flow and cardiac output. The document aims to educate the reader on the basic internal structures of the atria and their relationships to clinical functions.
Right Ventricle Anatomy, Physiology & ECHO Assessment by Dr. Vaibhav Yawalka...vaibhavyawalkar
This document provides an overview of right ventricle anatomy, physiology, and echocardiographic assessment. It describes the irregular shape and trabeculated structure of the right ventricle. The physiology section covers the RV's adaptation to volume overload through distensibility and compliance. Echocardiographic assessment techniques are outlined, including measurements of RV dimensions, fractional area change, TAPSE, tissue Doppler imaging, and the TEI index. The document provides a detailed but technical summary of right ventricular structure and function.
This document provides an overview of cardiac muscle structure and function. It defines key terms related to the properties of cardiac muscle such as rhythmicity, excitability, conductivity, and contractility. It describes the cardiac syncytium and normal conduction pathway in the heart. It explains excitation-contraction coupling in cardiac muscle and compares it to skeletal muscle. It also compares action potentials in the sinoatrial node and ventricular muscle. Finally, it discusses the significance of the plateau and refractory period in ventricular muscle action potentials.
1. Conduct of perfusion begins hours before CPB and involves assembling equipment, reviewing patient charts, calculating parameters, and priming the circuit.
2. Prior to initiating CPB, the perfusionist completes a safety checklist and confirms that all components are properly set up and functioning.
3. Once CPB begins, the perfusionist continuously monitors various parameters like blood flow, pressure, and oxygen levels and makes adjustments as needed throughout the procedure.
The document discusses the anatomy, physiology, assessment, and clinical significance of the right ventricle. Some key points include:
- The right ventricle is crescent-shaped and thinner-walled than the left ventricle. It has a higher preload and is more sensitive to changes in afterload.
- Assessment of the right ventricle includes echocardiography measures like fractional area change, TAPSE, and septal position. Hemodynamic measures include pulmonary artery pressures, pulmonary vascular resistance, and dP/dT.
- While able to accommodate volume overload, the right ventricle is poorly adapted for high pressures. Abnormalities in right ventricle size and function
The document summarizes key aspects of coronary blood flow regulation and determinants of myocardial oxygen consumption. It discusses how:
1) Myocardial contraction and oxygen delivery are closely linked, and the balance between oxygen supply and demand is critical for normal heart function.
2) The major determinants of myocardial oxygen consumption are heart rate, systolic pressure, and left ventricular contractility. Increases in these factors require proportional increases in coronary flow and oxygen delivery.
3) Coronary vascular resistance has three main components - epicardial conduit resistance, microcirculatory resistance, and extravascular compressive resistance which varies through the cardiac cycle. Maintaining the balance of these factors is important for adequate oxygen supply
Iabp instrumentation, indications and complicationsManu Jacob
1. Intra-aortic balloon counterpulsation (IABP) provides temporary circulatory support through systolic unloading and diastolic augmentation.
2. IABP is commonly used for patients in cardiogenic shock, high-risk PCI, and as a bridge to cardiac transplantation.
3. Contraindications include aortic insufficiency, aneurysm, and dissection. Complications include limb ischemia and thromboembolism.
The document discusses the anatomy and function of the heart and coronary arteries. It describes:
1. The heart anatomy including the 4 chambers and major blood vessels.
2. The coronary arteries which supply blood to the heart muscle, including the left and right coronary arteries and their branches.
3. How blood flows through the heart in two circuits - from the body to the lungs and back to the body.
4. The roles of the valves, muscles and tendons in regulating blood flow through the heart.
5. Atherosclerosis which occurs when plaque builds up in the coronary arteries, which can lead to heart attacks if it blocks blood flow.
This document provides an overview of the cardiovascular system, including:
- The heart's structure, chambers, valves, and conduction system.
- Blood flow through the heart and the events of the cardiac cycle.
- Types of blood vessels and circulation (pulmonary, systemic, coronary, hepatic portal).
- Functions of the cardiovascular system like oxygen transport and nutrient delivery.
- Key terms like stroke volume and cardiac output.
The cardiovascular system consists of two circuits - the pulmonary circuit and the systemic circuit. In the pulmonary circuit, deoxygenated blood is pumped from the right side of the heart to the lungs where it receives oxygen and returns to the left side of heart. In the systemic circuit, oxygenated blood is pumped from the left side of the heart through the aorta to the entire body, then returns to the right side of the heart. The heart is made up of four chambers - two upper atria which collect blood and two lower ventricles which pump blood out of the heart. It is surrounded and protected by membranes and contains valves that allow blood to flow in only one direction.
The cardiovascular system includes the heart and blood vessels. The heart weighs 200-400 grams and pumps around 7,751 litres of blood daily. It is located behind the sternum and is surrounded by membranes. Blood enters and exits the heart through major vessels while valves regulate flow between chambers. The heart muscle generates electrical impulses and contractions to circulate blood throughout the body. Cardiac output is regulated intrinsically through preload and afterload as well as extrinsically through the nervous and endocrine systems.
The document discusses the valves of the heart. There are two types of valves - atrioventricular valves and semilunar valves.
The atrioventricular valves include the tricuspid valve between the right atrium and ventricle, and the mitral/bicuspid valve between the left atrium and ventricle.
The semilunar valves include the pulmonary valve between the right ventricle and pulmonary artery, and the aortic valve between the left ventricle and aorta. Each valve has specific roles in regulating blood flow and preventing backflow through the heart chambers and vessels.
The coronary circulation refers to the blood vessels that supply and drain the heart. The heart receives its blood supply from two coronary arteries - the left and right coronary arteries. The left coronary artery supplies the left side of the heart including parts of the left atrium and ventricle. It branches into the anterior interventricular artery and circumflex artery. The right coronary artery supplies the right side of the heart and parts of the left side. It has branches like the right marginal artery and posterior interventricular artery. Deoxygenated blood from the heart drains into the coronary sinus and other cardiac veins before emptying into the right atrium.
This document provides an overview of the physiology of the cardiovascular system. It begins with an introduction and outlines the components and general functions of the CVS. It then discusses the anatomy of the heart, including its chambers and valves. It describes the pathway of blood flow through the heart and lungs. It explains cardiac muscle and the cardiac conduction system, including the sinoatrial node, atrioventricular node, bundle of His, and Purkinje fibers. It concludes with a discussion of the action potential in pacemaker cells and contractile cells in the heart.
The document summarizes the valves of the heart, including their structure, location, and function. There are two pairs of valves: atrioventricular valves (tricuspid and bicuspid/mitral) which allow blood to flow from the atria to the ventricles, and semilunar valves (pulmonary and aortic) which allow blood to exit the ventricles. The valves have cusps that open and close to ensure one-way blood flow and prevent backflow. Issues like stenosis can cause murmurs and increase pressures on the respective chambers of the heart.
The aortic valve has three leaflets (cusps) and is located between the left ventricle and the ascending aorta. It has important relationships with surrounding structures like the mitral valve, ventricular septum, and conduction bundles. The leaflets are attached to fibrous structures like the annulus, sinuses of Valsalva, and sinotubular junction. On echocardiogram, the aortic valve can be seen opening and closing from the parasternal long and short axis views. The document provides details on the anatomy, embryology, histology, and imaging of the aortic valve.
The document discusses factors that regulate cardiac output, including preload, contractility, and afterload. It describes how the respiratory pump, cardiac pump, muscle pump, and mean circulatory filling pressure affect cardiac output by changing preload. Sympathetic stimulation and hormones are discussed as factors increasing contractility. Methods for measuring cardiac output are also summarized, including the Fick principle, indicator dilution, thermodilution, Doppler echocardiography, and impedance cardiography. Cardiac output is increased in conditions like fever and anemia that cause increased metabolism, and decreased in states of weak contractions or poor pumping like congestive heart failure.
The coronary arteries arise from the ascending aorta and form a circulatory loop around the heart. The right coronary artery originates from the right sinus and supplies the right atrium and ventricle. The left coronary artery originates from the left sinus and divides into the left anterior descending artery and circumflex artery to supply the left side of the heart. Blood from the heart drains primarily into the coronary sinus which empties into the right atrium.
The right and left coronary arteries originate from the right and left sinuses of the aortic root. The right coronary artery supplies the right ventricle while the left coronary artery supplies the anterior portion of the ventricular septum and left ventricle. The left main coronary artery bifurcates into the left anterior descending artery and left circumflex artery. The left anterior descending artery supplies the majority of the left ventricle while the left circumflex artery supplies the left ventricle free wall. In approximately 70% of cases, the right coronary artery is the dominant artery supplying the posterior portions of the heart.
The cardiac cycle describes the sequence of events in one heartbeat. It involves systole, the contraction of the ventricles, and diastole, the relaxation of the ventricles. During atrial systole, the atria contract and blood passes to the relaxed ventricles. During ventricular systole, the ventricle walls contract and force blood out through the arteries. During diastole, the ventricles relax and blood flows back into the atria from the veins, completing the cycle.
Internal feature of right and left atriafarranajwa
This document provides information about the anatomy and structures of the right and left atria of the heart. It discusses the key internal features of each atrium, including chambers, valves, veins and arteries, muscle structures, and other anatomical landmarks. It also briefly explains some clinical significance of atrial structures, mentioning how abnormalities like atrial septal defects or atrial fibrillation can impact blood flow and cardiac output. The document aims to educate the reader on the basic internal structures of the atria and their relationships to clinical functions.
Right Ventricle Anatomy, Physiology & ECHO Assessment by Dr. Vaibhav Yawalka...vaibhavyawalkar
This document provides an overview of right ventricle anatomy, physiology, and echocardiographic assessment. It describes the irregular shape and trabeculated structure of the right ventricle. The physiology section covers the RV's adaptation to volume overload through distensibility and compliance. Echocardiographic assessment techniques are outlined, including measurements of RV dimensions, fractional area change, TAPSE, tissue Doppler imaging, and the TEI index. The document provides a detailed but technical summary of right ventricular structure and function.
This document provides an overview of cardiac muscle structure and function. It defines key terms related to the properties of cardiac muscle such as rhythmicity, excitability, conductivity, and contractility. It describes the cardiac syncytium and normal conduction pathway in the heart. It explains excitation-contraction coupling in cardiac muscle and compares it to skeletal muscle. It also compares action potentials in the sinoatrial node and ventricular muscle. Finally, it discusses the significance of the plateau and refractory period in ventricular muscle action potentials.
1. Conduct of perfusion begins hours before CPB and involves assembling equipment, reviewing patient charts, calculating parameters, and priming the circuit.
2. Prior to initiating CPB, the perfusionist completes a safety checklist and confirms that all components are properly set up and functioning.
3. Once CPB begins, the perfusionist continuously monitors various parameters like blood flow, pressure, and oxygen levels and makes adjustments as needed throughout the procedure.
The document discusses the anatomy, physiology, assessment, and clinical significance of the right ventricle. Some key points include:
- The right ventricle is crescent-shaped and thinner-walled than the left ventricle. It has a higher preload and is more sensitive to changes in afterload.
- Assessment of the right ventricle includes echocardiography measures like fractional area change, TAPSE, and septal position. Hemodynamic measures include pulmonary artery pressures, pulmonary vascular resistance, and dP/dT.
- While able to accommodate volume overload, the right ventricle is poorly adapted for high pressures. Abnormalities in right ventricle size and function
The document summarizes key aspects of coronary blood flow regulation and determinants of myocardial oxygen consumption. It discusses how:
1) Myocardial contraction and oxygen delivery are closely linked, and the balance between oxygen supply and demand is critical for normal heart function.
2) The major determinants of myocardial oxygen consumption are heart rate, systolic pressure, and left ventricular contractility. Increases in these factors require proportional increases in coronary flow and oxygen delivery.
3) Coronary vascular resistance has three main components - epicardial conduit resistance, microcirculatory resistance, and extravascular compressive resistance which varies through the cardiac cycle. Maintaining the balance of these factors is important for adequate oxygen supply
Iabp instrumentation, indications and complicationsManu Jacob
1. Intra-aortic balloon counterpulsation (IABP) provides temporary circulatory support through systolic unloading and diastolic augmentation.
2. IABP is commonly used for patients in cardiogenic shock, high-risk PCI, and as a bridge to cardiac transplantation.
3. Contraindications include aortic insufficiency, aneurysm, and dissection. Complications include limb ischemia and thromboembolism.
The document discusses the anatomy and function of the heart and coronary arteries. It describes:
1. The heart anatomy including the 4 chambers and major blood vessels.
2. The coronary arteries which supply blood to the heart muscle, including the left and right coronary arteries and their branches.
3. How blood flows through the heart in two circuits - from the body to the lungs and back to the body.
4. The roles of the valves, muscles and tendons in regulating blood flow through the heart.
5. Atherosclerosis which occurs when plaque builds up in the coronary arteries, which can lead to heart attacks if it blocks blood flow.
This document provides an overview of the cardiovascular system, including:
- The heart's structure, chambers, valves, and conduction system.
- Blood flow through the heart and the events of the cardiac cycle.
- Types of blood vessels and circulation (pulmonary, systemic, coronary, hepatic portal).
- Functions of the cardiovascular system like oxygen transport and nutrient delivery.
- Key terms like stroke volume and cardiac output.
The cardiovascular system consists of two circuits - the pulmonary circuit and the systemic circuit. In the pulmonary circuit, deoxygenated blood is pumped from the right side of the heart to the lungs where it receives oxygen and returns to the left side of heart. In the systemic circuit, oxygenated blood is pumped from the left side of the heart through the aorta to the entire body, then returns to the right side of the heart. The heart is made up of four chambers - two upper atria which collect blood and two lower ventricles which pump blood out of the heart. It is surrounded and protected by membranes and contains valves that allow blood to flow in only one direction.
The cardiovascular system circulates blood throughout the body using the heart as a pump. The heart has four chambers - two upper atria and two lower ventricles. It is surrounded by membranes and tissues. Blood enters the right atrium from the body, then passes to the right ventricle which pumps it to the lungs. Oxygenated blood returns to the left atrium and passes to the left ventricle which pumps it out to the body via the aorta. The heart contracts over 100,000 times per day to circulate blood through the pulmonary and systemic circuits. Valves ensure blood only flows in one direction through the heart.
The human heart is a muscular organ that provides continuous blood circulation through the cardiac cycle. It is located in the middle of the chest behind the sternum. The heart is divided into four chambers - two upper atria and two lower ventricles. Blood flows through the heart via heart valves which allow blood to flow in one direction. The heart's rhythm is controlled by the sinoatrial node which generates electrical signals to coordinate contractions. The cardiac cycle consists of diastole where chambers fill with blood and systole where ventricles contract to pump blood out of the heart. The circulatory system transports blood from the heart to tissues and back again via different circulatory routes.
The heart is divided into four chambers that receive and pump blood throughout the body. The two upper chambers, called atria, receive blood returning to the heart while the two lower chambers, called ventricles, pump blood out to the body and lungs. The heart wall contains three layers and uses electrical signals to coordinate contractions that pump blood in two phases of the cardiac cycle. Valves allow blood to flow in only one direction through the heart and into the major arteries and veins.
The document provides information about the structure and function of the heart. It describes the four chambers and valves of the heart and how blood flows through the heart in two separate pumps (pulmonary and systemic circulation). It also discusses the conduction system that controls heart rate, including the sinoatrial node and atrioventricular node. Blood pressure is defined and the factors that influence it are explained. An electrocardiogram is used to measure the heart's electrical activity.
The document provides information about the anatomy and physiology of the heart. It discusses the following key points in 3 sentences:
The heart is a muscular organ located in the mediastinum that pumps blood through the circulatory system via four chambers - two upper atria and two lower ventricles. It has three layers - epicardium, myocardium and endocardium - and is surrounded by the pericardium. The heart has a conduction system including the sinoatrial node which acts as the pacemaker, generating electrical impulses that cause coordinated contractions of the atria and ventricles to efficiently circulate blood.
The document describes the structure and function of the heart. It discusses the location of the heart in the mediastinum and its external and internal anatomy. The four chambers of the heart (right and left atria and ventricles) are described along with the valves that regulate blood flow. The circulations of blood through the pulmonary system and systemic circulation are also summarized. Key details about the layers of the heart wall, coronary circulation and blood flow through arteries, capillaries and veins are provided.
The cardiovascular system consists of the heart and blood vessels. The heart has four chambers and pumps blood through two circuits. Blood vessels include arteries, which carry blood away from the heart, and veins, which carry blood back to the heart. Capillaries allow for gas and nutrient exchange between blood and tissues. The cardiovascular system circulates blood through the lungs to receive oxygen and remove carbon dioxide, and through the body to deliver oxygen and nutrients to tissues.
The circulatory system consists of the lymphatic and blood circulations. The blood circulation transports nutrients, oxygen, and waste throughout the body via arteries, veins, and capillaries driven by the heart. Blood is composed of plasma and blood cells including red blood cells, white blood cells, and platelets. The heart pumps blood through two circuits - pulmonary circulation to exchange gases in the lungs and systemic circulation to exchange substances in tissues throughout the body.
CARDIO VASCULAR SYSTEM.pdf for bsc nursing studentsshanmukhadevi
The cardiovascular system refers to the heart, blood vessels and the blood.
Blood contains oxygen and other nutrients, which your body needs to survive. The body takes these essential nutrients from the blood.
At the same time, the body dumps waste products like carbon dioxide, back into the blood, so they can be removed.
The main function of the cardiovascular system is therefore to maintain blood flow to all parts of the body, to allow it to survive.
Veins deliver used blood from the body back to the heart. Blood in the veins is low in oxygen (as it has been taken out by the body) and high in carbon dioxide (as the body has unloaded it back into the blood).
All the veins drain into the superior and inferior vena cava, which then drain into the right atrium.
The right atrium pumps blood into the right ventricle. Then the right ventricle pumps blood to the pulmonary trunk, through the pulmonary arteries and into the lungs.
In the lungs the blood picks up oxygen that we breathe in and gets rid of carbon dioxide, which we breathe out. The blood is becomes rich in oxygen, which the body can use.
From the lungs, blood drains into the left atrium and is then pumped into the left ventricle. The left ventricle then pumps this oxygen-rich blood out into the aorta, which then distributes it to the rest of the body through other arteries.
This blood will again return back to the heart through the veins and the cycle continues.
The cardiovascular system can be thought of as the transport system of the body.
This system has three main components: the heart, the blood vessel and the blood itself.
The heart is the system's pump and the blood vessels are like the delivery routes.
Blood can be thought of as a fluid, which contains the oxygen and nutrients the body needs and carries the wastes, which need to be removed.
194 anatomy and function of the coronary arteriesSHAPE Society
The document discusses the anatomy and function of the heart and coronary arteries. It describes:
1. The heart anatomy including the 4 chambers and major blood vessels.
2. The coronary arteries which supply blood to the heart muscle, including the left and right coronary arteries and their branches.
3. How blood flows through the heart in two circuits - from the body to the lungs and back to the body.
4. The roles of the valves, muscles and tendons in regulating blood flow through the heart.
5. How blockages in the coronary arteries can lead to heart attacks by depriving parts of the heart muscle of oxygenated blood.
The document discusses the anatomy and function of the heart and coronary arteries. It describes:
1. The heart anatomy including the 4 chambers and major blood vessels.
2. The coronary arteries which supply blood to the heart muscle, including the left and right coronary arteries and their branches.
3. How blood flows through the heart in two circuits - from the body to the lungs and back to the body. The heart valves and muscles that regulate blood flow are also described.
Muscular System: The Cardiac Muscle (Heart)hm alumia
The cardiac muscle is only found in the heart. It contracts involuntarily and has intercalated discs between cells. The heart is located in the middle mediastinum behind the sternum. It is surrounded by pericardium and has endocardium, myocardium, and epicardium layers. The heart has four chambers - right and left atria receive blood while right and left ventricles pump it out. Blood flows through valves between chambers.
The circulatory system is divided into the heart and blood vessels. The heart pumps blood into the pulmonary and systemic circulations. The right side pumps blood to the lungs and the left side pumps oxygenated blood to the rest of the body. The heart has four chambers, valves to ensure one-way blood flow, and a conducting system to coordinate contractions. Arteries carry blood away from the heart while veins return blood to the heart.
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Anatomy And Physiology of Human Heart
1. ANATOMY OF THE HEART By: Dr Mohammed Faez
2. The Heart The heart is a chambered muscular organ that pumps blood received from the veins into the arteries, thereby maintaining the flow of blood through the entire circulatory system.
3. The Heart • The heart is surrounded by membrane called Pericardium.
4. The Pericardium • The pericardium is a fibroserous sac that encloses the heart and the roots of the great vessels. • The pericardium lies within the middle mediastinum.
5. The Pericardium
6. The Pericardium • Its function is to restrict excessive movements of the heart as a whole and to serve as a lubricated container in which the different parts of the heart can contract.
Cardiovascular physiology for university studentsItsOnyii
A detailed pdf document on cardiovascular physiology for university students including structure and functions of heart, Electrocardiogram, echocardiography, chest and limb leads, Diseases and disorders of the heart.
A powerpoint designed for the South African Life Sciences syllabus for grade 11. Includes information about blood and it's transportation, the human heart, the lymph system etc. Hope it helps :)
✓Heart
✓Anatomy of heart
✓Blood circulation
✓Blood Vessels
✓Structure and function of artery, vein and capillaries
✓Elements of conduction system of heart and heart beat
✓Its regulation by nervous system
✓Cardiac output
✓Cardiac cycle
✓Regulation of bood pressure
✓Pulse
✓Electrocardiogram
✓Disorder of heart
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2. The Heart
• To understand the ECG, it helps to understand
the heart and how the heart works
3. The Heart
• Fun Fact
– The average heart beats 100,000 times, pumping
about 2,000 gallons of blood each day!!
4. The Heart
• Fun Fact
– The adult heart weighs approximately 11oz and is
about the size of its owner’s fist
• A person’s heart size and weight are influenced by their
age, body weight and build, frequency of physical
exercise, and heart disease
5. The Heart
• Your heart is a muscular organ that acts like a
pump to send blood throughout your body
• Your heart is located under the ribcage in the
center of your chest between your right and
left lung
• Your heart is at the center of your circulatory
system, which delivers blood to all areas of
your body
6. The Heart
• Your Heart is vital to your health and nearly
everything that goes on in your body
– Without the heart’s pumping action, blood can’t
circulate within your body
• Your blood carries the oxygen and nutrients
that your organs need to function normally.
– Blood also carries carbon dioxide, a waste
product, to your lungs to be passed out of your
body and into the air
7. The Heart
• Pericardium
– Protective sac that surrounds the heart
• Within the pericardium is about 10 mL of serous fluid
that acts as a lubricant, preventing friction as the heart
beats
9. Heart Chambers
• The two upper chambers of your heart are
called atria
• The atria receive and collect blood
10. Heart Chambers
• The right atrium
– Receives deoxygenated blood returning from the
body through the inferior and superior vena cavae
and from the heart through the coronary sinus
11. Heart Chambers
• The left atrium
– Receives oxygenated blood from the lungs
through the four pulmonary veins
12. Heart Chambers
• The interatrial septum divides the chambers
and helps them contract
• Contraction of the atria forces blood into the
ventricles below
13. Heart Chambers
• The two lower chambers of your heart are
called ventricles
• The ventricles pump blood out of your heart
into the circulatory system to other parts of
your body
14. Heart Chambers
• Right ventricle
– Receives blood from the right atrium and pumps it
through the pulmonary arteries to the lungs,
where it picks up oxygen and drops off carbon
dioxide
15. Heart Chambers
• Left ventricle
– Receives oxygenated blood from the left atrium
and pumps it through the aorta and then out to
the rest of the body
16. Heart Chambers
• The right and left sides of your heart are
divided by an internal wall of tissue called the
septum
17. Great Vessels
• There are blood vessels attached to the heart
that transport blood to and from the lungs
and body
– Pulmonary arteries and veins
– Aorta
– Superior and inferior vena cava
20. Great Vessels
• Superior and Inferior Vena Cava
– Send unoxygenated blood from the body to the
heart
21. The Heart as a Pump
• The left side
– Pumps oxygenated blood and nutrients to the
body’s organs, muscles, and tissues
• The right side
– Pumps deoxygenated blood to the lungs to
exchange carbon dioxide for oxygen
22. Heart Valves
• With each heartbeat, the heart relaxes and
contracts
• During relaxation
– The heart relaxes and fills with blood
• During contraction
– The heart squeezes and pumps blood out to the
body
23. Heart Valves
• For the heart to function properly, your blood
flows in only one direction
– Your heart’s valves make this possible
24. Heart Valves
• The valves make sure the blood travels in only
one direction
Blood travels
from the body
to the right
atrium
Through the Through the
aortic valve into tricuspid valve
the aorta and into the right
out to the body ventricle
Traveling into
Through the
the left atrium,
pulmonic valve
through the
into the
mitral valve into
pulmonary
the left
arteries
ventricle
25. Heart Valves
• Healthy valves open and close in very exact
coordination with the pumping action of your
heart’s atria and ventricles
• When your heart beats, the valves make a
“LUB-DUB” sound that can be heard with a
stethoscope
26. Heart Valves
• Four Valves of the Heart
– Aortic
– Mitral
– Pulmonary
– Tricuspid
27. Heart Valves
• Tricuspid valve
– Regulates blood flow between the right atrium
and right ventricle
28. Heart Valves
• Pulmonary valve
– Controls blood flow from the right ventricle into
the pulmonary artery, which carries blood to your
lungs to pick up oxygen
29. Heart Valves
• Mitral valve
– Lets oxygen-rich blood from your lungs pass from
the left atrium into the left ventricle
30. Heart Valves
• Aortic valve
– Opens the way for oxygen-rich blood to pass from
the left ventricle into the aorta, your body’s
largest artery, where it is delivered to the rest of
your body
31. Heart Valves
Atrioventricular (AV) Semilunar (SL)
• Tricuspid valve • Pulmonic valve
– Right side of the heart – Right side of the heart
– Separates right atrium and – Between right ventricle and
right ventricle pulmonary artery
• Mitral valve (bicuspid) • Aortic valve
– Left side of the heart – Left side of the heart
– Separates left atrium and left – Between left ventricle and
ventricle aorta
32. Coronary circulation
• The heart has it’s own circulatory system to
supply it with oxygen (coronary arteries) and
to remove deoxygenated blood (coronary
veins)
33. Myocardial Ischemia and Infarction
• Myocardial ischemia
– Occurs when the flow of blood through a coronary
artery is decreased, the cardiac muscle tissue fed
by the coronary artery is deprived of oxygen and
nutrients
34. Myocardial Ischemia and Infarction
• Myocardial Infarction (MI) or Heart Attack
– Occurs when one of the arteries that supplies the
heart muscle becomes blocked
– Blockage may be caused by spasm of the artery or
by atherosclerosis with acute clot formation
– The blockage results in damaged tissue and a
permanent loss of contraction of this portion of
the heart muscle
35. Layers of the Heart Wall
• The heart wall is made up of three tissue
layers
– Epicardium
– Myocardium
– Endocardium
36. Layers of the Heart Wall
• Epicardium
– Is the external or outer layer of the heart. This is
where the coronary arteries and veins are found
37. Layers of the Heart Wall
• Myocardium
– Is the middle and thickest layer of the heart and is
responsible for the contraction of the heart
38. Layers of the Heart Wall
• Endocardium
– Is the innermost layer of the heart
39. Cardiac Cells
• There are two basic types of cardiac cells in
the heart:
– Pacemaker
– Myocardial cells
40. Cardiac Cells
• Pacemaker cells (electrical cells)
– Responsible for the spontaneous generation and
conduction of electrical impulses
– Found in the electrical conduction system of the
heart
41. Cardiac Cells
• Myocardial cells (working cells)
– Contain contractile filaments that are
interconnected
– When electrically stimulated, the filaments slide
together and the myocardial cell contracts
– These cells form the myocardium (muscular layer
of the heart)
– These are the working cells and are responsible
for contraction and relaxation
42. Properties of Cardiac Cells
• Automaticity
– Is the ability of the pacemaker cells to
spontaneously initiate an electrical impulse. Only
pacemaker cells have the property of automaticity
– fires impulses regularly
• Contractility
– Refers to the ability of the myocardial cells to
shorten causing cardiac muscle contraction in
response to an electrical stimulus
43. Properties of Cardiac Cells
• Conductivity
– Is a property that refers to the ability of all cardiac
cells to receive and conduct an electrical impulse
to an adjacent cardiac cell
• Excitability
– Refers to the electrical irritability of all cardiac
cells because of an ionic imbalance across the
membranes of cells
44. Properties of Cardiac Cells
Type of Cardiac Cell Where Found Primary Function Properties
Myocardial cells Myocardium Contraction and Contractility
“working cells” relaxation Excitability
Pacemaker cells Electrical Generation and Automaticity
“Electrical cells” conduction system conduction of Conductivity
electrical impulses Excitability
45. Autonomic Nervous System Effects on
the Heart
• The nervous system innervates the heart and
alters the heart rate, force of contraction,
cardiac output, and blood pressure when
stimulated
46. Autonomic Nervous System Effects on
the Heart
• Parasympathetic nerve fibers
– Originate from the inhibitory center of the brain
via the vagus nerve
• Stimulation of this nerve causes the release of
acetylcholine, which decreases the heart rate, force of
contraction, cardiac output , and blood pressure
47. Autonomic Nervous System Effects on
the Heart
• Sympathetic nerve fibers
– Originate from the accelerator center in the brain
– Stimulation of these nerve fibers results in the
release of norepinephrine, which increases the
heart rate, force of contraction, cardiac output,
and blood pressure
48. Understanding the Heart’s Electrical
System
• The heart has an internal electrical system that
controls the speed and rhythm of the heartbeat.
• With each heartbeat, an electrical signal spreads
from the top of the heart to the bottom
• As it travels, the electrical signal causes the heart
to contract and pump blood
• The process repeats with each new heartbeat
• A problem with any part of this process can cause
an arrhythmia
50. Understanding the Heart’s Electrical
System
• The normal conduction Pathway
– The SA node fires causing atria to contract and pump
blood into the ventricles
– The impulse travels through the atria to the AV node
• The AV node briefly delays the impulse allowing time for the
ventricles to fill with blood
– The impulse then travels through the Bundle of HIS,
right and left bundle branches and Purkinje fibers
• Causing the ventricles to contract
– The ventricles then relax, then the heartbeat process
starts all over again in the SA node
– Youtube: The Heart's electrical system (0.27)
51. Parts of the Electrical Conduction
System
• SA node
• AV node
• Bundle of His
• Right and Left Bundle Branches
• Purkinje Fibers
52. Parts of the Electrical Conduction
System
• SA (Sino-atrial) node
– Located in the right upper atrium
– Called the normal pacemaker of the heart
• It initiates the electrical impulse that is sent through
the heart
53. Parts of the Electrical Conduction
System
• AV (atrioventricular) node
– Located in the lower right atrium and functions as
a “gatekeeper” to the ventricles
– It delays the impulses from the SA node and atria
for a fraction of a second before sending the
impulse to the ventricles
– It also will prevent extra beats from being
conducted to the ventricles
54. Parts of the Electrical Conduction
System
• Bundle of His
– Directly attached to the AV node and extends
from the top left corner of the right ventricle to
the top of the intraventricular septum
– It sends the impulses from the AV node rapidly to
the lower part of the conduction system in the
ventricles
55. Parts of the Electrical Conduction
System
• Right and Left Bundle Branches
– Divided from the Bundle of His
– Found in the intraventricular septum and across
the lower portion of the right and left ventricles
56. Parts of the Electrical Conduction
System
• Purkinje Fibers
– Subdivided into smaller fibers from the right and
left bundle branches
– Distribute the electrical impulse from the bundle
branches to the individual muscle cells in the
ventricles
57. Understanding the Heart’s Electrical
System
• The normal conduction Pathway
– The SA node fires causing atria to contract and pump
blood into the ventricles
– The impulse travels through the atria to the AV node
• The AV node briefly delays the impulse allowing time for the
ventricles to fill with blood
– The impulse then travels through the Bundle of HIS,
right and left bundle branches and Purkinje fibers
• Causing the ventricles to contract
– The ventricles then relax, then the heartbeat process
starts all over again in the SA node
– Youtube: The Heart's electrical system (0.27)
58. Pacemaker Sites of the Conduction
System
• There are three intrinsic pacemaker sites
within the conduction system
• Each site can produce an electrical impulse or
impulses and control the heart rate
59. Pacemaker Sites of the Conduction
System
• The intrinsic rate of each site is as follows:
– SA node
• 60-100 bpm
– AV junction
• 40-60 bpm
– Ventricles
• 20-40 bpm
60. Pacemaker Sites of the Conduction
System
• Normally, the SA node is the pacemaker of the
heart
– If the sinus node slows down or fails to initiate
depolarization (contraction), either the AV
junction or the ventricles will spontaneously
produce electrical impulses
61. The Cardiac Cycle
• The period from the beginning of one
heartbeat to the beginning of one heartbeat
to the beginning of the next one
• Consists of 2 events
– Mechanical
– Electrical
62. The Cardiac Cycle
• Mechanical Events
– The mechanical part of the cardiac cycle is divided
into two phases: diastole (rest) and systole
(contraction). The atria and ventricles contract
and relax in tandem to effectively pump blood
through the heart
63. The Cardiac Cycle
• Mechanical Events
– During atrial systole (contraction) and ventricular
diastole (relaxation), the atria conract and squeeze
blood into the ventricles
– The ventricles are “at rest” and fill with blood
64. The Cardiac Cycle
• Mechanical Events
– During atrial diastole (relaxation) and ventricular
systole (contraction), the atria are “at rest” and fill
with blood, while the ventricles contract and
squeeze blood out of the heart
65. The Cardiac Cycle
• Electrical Events
– The electrical events that occur in the heart
muscle are called depolarization and
repolarization
– The exchange of electrolytes (minerals in your
body that carry an electric charge) across
myocardial cell walls creates the electrical events
that stimulate the heart muscle to contract
– The major electrolytes that affect cardiac function
are sodium and potassium
66. The Cardiac Cycle
• Electrical Events
– Depolarization is the formation and spread of
electrical activity in the heart
– During depolarization, the inside of the cell
becomes more positive
– Depolarization results in contraction of the heart
muscle
– During depolarization, the cardiac cells are in a
refractory state, which means that they are
resistant to additional electrical activity
67. The Cardiac Cycle
• Electrical Events
– Repolarization is the return of the cells to the
resting or polarized state
– During repolarization, the inside of the cell
becomes more negatively charged
• Known as the recovery phase
– Repolarization results in relaxation of the heart
muscle