1.1 INTRODUCTION CARDIOLOGY : The scientific study of the normal heart & the diseases associated with it. The heart pumps blood into two anatomically separate systems of blood vessels - 1. Pulmonary circulation. 2. Systemic circulation.
1. PULMONARY CIRCULATION Circulation of blood from the right ventricle of the heart to the lungs & back to the left atrium.2.SYSTEMIC CIRCULATION Blood pumped out from the left ventricle is carried by the branches of the aorta around the body & returns to the right atrium.
1.2 HEART ANATOMY Approximately the size of your fist. 12 cm long , 9 cm wide at its broad point & 6 cm thick. Weighs 250 g in adult females and 300 g in adult males. Location : Lies in the Thorasic region in the Mediastinum. Anterior to Vertebral column. Posterior to Sternum. Lies upon Diaphragm. Slightly left of midline.
ANATOMY : LAYERS OF THE HEART WALL Made up of three layers. 1. Epicardium (External layer) : → Visceral layer of the serous pericardium. → Composed of Mesothelium & delicate Connective tissue. 2. Myocardium (Middle layer) : → Cardiac muscle tissue. → Responsible for pumping action of the heart. → Striated like skeletal muscle. 3. Endocardium (Innermost layer) : → Thin layer of Endothelium overlying a thin layer of Connective tissue. → Provides smooth lining for the chambers. → Covers the valves of the heart.
ANATOMY : CHAMBERS OF THE HEART Two atria to receive blood. Two ventricles to pump blood. ATRIUM (Receiving chambers) :• Partition between Right Atrium & Left Atrium – Inter Atrial Septum. Right Atrium : → Receives blood from three veins. → Posterior wall – Smooth. → Anterior wall – Rough. Left Atrium : → Forms most of the base of the heart. → Receives blood from lungs through 4 pulmonary veins. → Posterior & Anterior walls – Smooth.
ANATOMY : CHAMBERS OF THE HEARTVENTICLES (Discharging chambers) : Partition between Right Ventricle & Left Ventricle – Inter Ventricular Septum. Right Ventricle : → Blood enters from Right atrium through Tricuspid valve. → Passes blood into pulmonary trunk through pulmonary valve. → Contains series of ridges called trabeculae carneae. Left Ventricle : → Forms the apex of the heart. → Blood enters from Left Atrium through Bicuspid valve. → Passes blood into Ascending Aorta through the Aortic valve.
1.3 PHYSIOLOGY OF THE HEART FLOW OF BLOOD THROUGH THE HEART : Superior & Inferior venae cavae empty into the Right Atrium. Blood Atrioventricular valve Right Ventricle Pulmonary artery. Left & Right Pulmonary arteries carry venous blood to the lungs. Pulmonary veins carry oxygenated blood back to the left atrium. Blood Atrioventricular valve Left Ventricle Aorta Both atria contract at the same time and is followed by the simultaneous contraction of both the ventricles. Muscle layer of the walls of atria is thinner than the ventricles.
1. Myocardial Infarction (Heart Attack):Happens when blood flow to a part of the heart is suddenly blocked.Most visible sign of heart disease.Symptoms: Feel pressure or pain in the middle of chest. May extend into shoulder and arm or into abdomen or jaw. Shortness of breath. Sweating. Nausea or vomiting. Weakness or lightheadedness. Paleness
2. Cardiac Arrhythmias Called heart rhythm disorder. Is an irregular heartbeat. Can occur if the electrical signals that control the heartbeat are delayed or blocked. Smoking, heavy alcohol use, use of certain drugs or too much caffeine or nicotine can lead to arrhythmias.Symptoms : Dizziness chest pain fainting
3. ANGINA Angina is a symptom of coronary artery disease. Is chest pain or discomfort that occurs when heart muscle does not get enough blood. Feel like pressure or asqueezing pain in chest.