Cardiovascular and peripheral vascularDocument Transcript
Cardiovascular and Peripheral VascularCognitive ObjectivesUpon completion of this lesson, the student should be able to: 1. Define systole and diastole. Systole = period of ventricular contraction. During systole, the left ventricle starts to contract and ventricular pressure rapidly exceeds left atrial pressure shutting the mitral valve. Closure of the mitral valve produces the first heart sound, S1.Diastole = period of ventricular relaxation. During diastole, pressure in the blood filled leftatrium slightly exceeds that in the relaxed left ventricle and blood flows from left atrium to leftventricle across open mitral valve. Just before onset of ventricular systole, atrial contractionproduces a slight pressure rise in both chambers 2. If given a drawing of the anterior chest identify the position of important cardiac structures that lie underneath the chest wall. (pg 324) Right ventricle and pulmonary artery forms a wedgelike structure behind and to the left of the sternum. Inferiorly lies below junction of the sternum and the xiphoid process. Right ventricle narrows superiorly and joins the pulmonary artery at the level of the sternum or base of the heart (superor aspect of the ehart at the right and left 2nd interspaces next to the sternum). Left ventricle, behind the right ventricle and to the left forms left lateral margin of the heart. Inferior tip of the left ventricle is known as cardiac apex, upon palpitation known as point of maximal impulse of PMI. Located at 5 interspace 7cm to 9cm lateral to the midsternal line. Displacement of PMI lateral to midclavicular lie of greater than 10 cm lateral to midsternal line suggest left ventricularly hypertrophy. Above the heart lies the great vessels. Aorta curves upward from the left ventricle to the level of the sterna angle. Pulmonary arteries bifurcates quickly into left and right branches. On medial border, locates superior and inferior venae cavae. 3. Describe the structure and the function of the atrioventricular and semilunar valves. (pg 325) Atrioventricular valves – (right) tricuspid and (left) mitral valves. Function to prevent backflow. Semilunar valves – aortic/pulmonary valves, has leaflets shaped like half moon. Function prevent backflow. 4. Describe the characteristics of the normal pulse. Rate – 60-90 Rhythm - regular Quality – not tready 5. Describe the effect of inspiration on heart rate.
Inspiration increase preload and increased volume of blood flow from exercising muscles. 6. Identify the role of the atrioventricular valves in the formation of S1. During systole, the left ventricle starts to contract and ventricular pressure rapidly exceeds left atrial pressure, shutting the mitral valve. Closure of the mitral valve produces the first heart sound, S1. 7. Identify the role of the semilunar valves in the formation of S2. As left ventricular pressure continues to rise, it quickly exceeds pressure in the aorta and forces the aortic valve open. In some pathologic conditions, an early systolic ejection sound (Ej) accompanies the opening of the aortic valve. Normally, maximal left ventricular pressure corresponds to systolic blood pressure. As left ventricle ejects most of its blood, ventricular pressure begins to fall. When left ventricular pressure drops below aortic pressure, the aortic valve shuts. Aortic valve closure produces the second heart sound, S2, and another diastole begins. 8. Describe the flow of blood through the heart making sure to differentiate diastolic and systolic flow.CARDIAC CHAMBERS, VALVES, AND CIRCULATIONTricuspid and Mitral valves are often called atrioventricular valves. Aortic and pulmonic valvesare called semilunar valves because each of their leaflets is shaped like a half moon.As the heart valves close, the heart sounds arise from vibrations emanating from the leaflets.EVENTS IN THE CARDIAC CYCLEThe heart serves as a pump that generates varying pressures as its chambers contract and relax.Systole is the period of ventricular contraction. Pressure in the LV rises from less than 5 mm Hgin its resting state to normal peak of 120 mm Hg. After ventricle ejects blood into aorta, pressurelevels off and starts to fall. Diastole is the period of ventricular relaxation. Ventricular pressure
falls further to below 5 mm Hg, and blood flows from atrium to ventricle. Late diastole,ventricular pressure rises slightly during inflow of blood from atrial contraction. 9. Define “apical pulse” (PMI) and identify its normal location on the chest wall. Point of maximal impulse. The apical impulse represents the brief early pulsation of the left ventricle as it moves anteriorly during contraction and touches the chest wall. Try to access this with patient supine. Located on midclavicular line in usually the 5th interspace. 10. Describe the location of the Aortic, Pulmonic, Tricuspid, and Mitral areas on the chest wall.RELATION OF AUSCULTATORY FINDINGS TO THE CHEST WALLListen to heart sounds and murmurs help identify the valve or chamber where they originate.Murmurs arising from: • Mitral valve are usually heard best at and around the cardiac apex. • Tr i c u s p i d v a l v e a r e h e a r d b e s t a t o r n e a r t h e l o w e r l e f t s t e r n a l b o r d e r. • Pulmonic valve are usually heard best in the 2nd & 3rd left interspaces close to the sternum but at times may also be heard at higher or lower levels. • Aortic valve may be heard anywhere from the right 2nd interspace to the apex. These areas overlap, you will need to correlate auscultatory findings with other cardiac e x a m i n a t i o n f i n d i n g s t o i d e n t i f y s o u n d s a n d m u r m u r s a c c u r a t e l y. 11. Define “jugular venous pressure (JVP)” and identify why “JVP” is measured during the cardiovascular exam.
Jugular venous pressure reflects right atrial pressure, which in turn equals central venous pressure and right ventricular end-diastolic pressure. JVP is best estimated from right internal jugular vein. JVP falls with loss of blood and increases with right or left heart failure, pulmonary hypertension, tricuspid stenosis, and pericardial compression or tamponade. JVP gives clues about volume status, right and left ventricular function, patency of tricuspid and pulmonary valves, pressure in pericardium, and arrhythmias. 12. Define “bruit” and explain its causes. A murmur-like sound of vascular origin in artery. Wikipedia: Bruit is the term for the unusual sound that blood makes when it rushes past an obstruction (called turbulent flow) in an artery when the sound is auscultated with the bell portion of a stethoscope. 13. Define “thrill” and identify its causes.During palpitation of carotid artery, you may detect humming vibrations, or thrills, that feel likethe throat of a purring cat. Formed by turbulence of underlying murmurs.P a l p a t i o n i s a l s o v a l u a b l e f o r d e t e c t i n g t h r i l l s , t h e t i m i n g o f S 1 a n d S 2, a n d t h e v e n t r i c u l a rm o v e m e n t s o f S 3 o r S 4.EXAMPLES OF ABNORMALITIEST h r i l l s m a y a c c o m p a n y l o u d , h a r s h , o r r u m b l i n g m u r m u r s a s i n : ao r t i c s t e n o s i s , patent ductus arteriosus, ventricular septal defect, a n d , l e s s c o m m o n l y, m i t r a l stenosis.T h e y a r e p a l p a t e d m o r e e a s i l y i n p a t i e n t p o s i t i o n s t h a t a c c e n t u a t e t h e m u r m u r.• Begin with general palpation of the chest wall. First palpate for heaves, lifts, or thrills, usingy o u r f i n g e r p a d s . H o l d t h e m f l a t o r o b l i q u e l y o n t h e b o d y s u r f a c e . Ve n t r i c u l a r i m p u l s e s m a yheave or lift your fingers.• Check for thrills, formed by the turbulence of underlying murmurs, by pressing the ball ofy o u r h a n d f i r m l y o n t h e c h e s t . I f s u b s e q u e n t a u s c u l t a t i o n r e v e a l s a l o u d m u r m u r, g o b a c k t othat area and check for thrills again.EXAMPLES OF ABNORMALITIESOn rare occasions, a patient has dextrocardia—a heart situated on the right side. The apicalimpulse will then be found on the right. If you cannot find an apical impulse, percuss for thedullness of the heart and liver and for the tympany of the stomach. In situs inversus, all threeof these structures are on opposite sides from normal. A right-sided heart with a normallyplaced liver and stomach is usually associated with congenital heart disease. 14. Define “lift” and “heave” and identify their causes.
Begin with general palpation of the chest wall. Palpate for h e a v e s , l i f t s , or t h r i l l s , using yourf i n g e r p a d s . Hold them flat or obliquely on the body surface. Ventricular impulses may heave orlift your fingers. 15. Describe the mechanisms responsible for the development of a physiologic splitting of S2. Consider the second heart sound, S2, and it s two components, A2, and P2 caused by closure of aortic and pulmonary valves. During inspiration, the right heart filling time is increased which increases ventricular stroke volume and duration of the right ventricular ejection compared with the neighboring left ventricle. This delays the closure of the pulmonary valve, P2, splitting S2 into its two audible components. During expiration, these two components fuse into a single sound, S2. P2 is relatively soft in compared to S2, and is heard best in its own area, 2nd/3rd left interspaces close to the sternum. 16. Describe the physiologic mechanisms responsible for the development of an S3 and S4.S3 - physiologic S3 occurring early in diastole during rapid ventricular filling, it is later than anopening snap, dull and low in pitch, and heard best at the apex in the left lateral decubitusposition. The bell of the stethoscope should be used with very light pressure. A pathologic S3 orventricular gallop sounds just like a physiologic S3. Arising from altered left ventricularcompliance at the end of the rapid filling phase of diastole.From Wikipedia:S3 occurs at the beginning of diastole after S2 and is lower in pitch than S1 or S2 as it is not ofvalvular origin. S3 is thought to be caused by the oscillation of blood back and forth between thewalls of the ventricles initiated by inrushing blood from the atria. The reason the third heartsound does not occur until the middle third of diastole is probably because during the early partof diastole, the ventricles are not filled sufficiently to create enough tension for reverberation. Itmay also be a result of tensing of the chordae tendineae during rapid filling and expansion of theventricle. In other words, an S3 heart sound indicates increased volume of blood within theventricle”S4 - An S4 (atrial sound or atrial gallop) occurs just before S1. It is dull, low in pitch, and heardbetter with the bell. Due to increased resistance to ventricular filling following atrial contraction.This increased resistance is related to decreased compliance (increase stiffness) of the ventricularmyocardium.From Wikipedia:“This gallop is produced by the sound of blood being forced into a stiff/hypertrophic ventricle. Itis a sign of a pathologic state, usually a failing left ventricle, but can also be heard in otherconditions such as restrictive cardiomyopathy. The sound occurs just after atrial contraction("atrial kick") at the end of diastole and immediately before S1. 17. Identify in what type of patients you would commonly hear an S3 or S4.
S3 is typically in children and in young adults to the age of 35 or 40. Common during lasttrimester of pregnancy. Sounds like “Kentucky.”S4 (atrial sound or gallop) occurs before S1. Heard occasionally in normal person, especially intrained athletes and older age groups. May sound like Tennessee. 18. Describe the following characteristics of a "functional" (physiologic or innocent) murmur: timing, shape, location of maximal impulse, radiation, intensity, pitch, and quality.Midsystolic ejection murmurs are the most common kind of heart murmur. They may be (1)innocent—without any detectable physiologic or structural abnormality;(2) physiologic—from physiologic changes in body metabolism; or(3) pathologic—arising from a structural abnormality in the heart or great vessels.The characteristics of a innocent/physiologic murmur are:Timing – between S1 and S2Shape – crescendo-decrescendo, or diamond shapeLocation of maximal impulse – 2nd to 4th interspaces between the left sterna border and the apexRadiation - littleIntensity – grade 1 to 2, possibly 3Pitch – soft to mediumQuality - variable 19. Define “clubbing” and describe why it can occur in cardiovascular disease.Clinically a bulbous swelling of the soft tissue at the nail base, with loss of normal angle btwnnail & proximal nail fold. Angle ↑ ≥ 180◦, nail bed feels spongy / floating.Mechanism: still unknown. May involve vasodilation w/↑ blood flow to distal portion of digitsand changes in connective tissue, possibly fr. Hypoxia, ∆ in innervation, Genetics, Platelet-derived GF fr. fragment of platelet clumps.Seen in pt. w/ a) CHD b) Interstitial lung disease c) Lung CA d) IBD e) Malignancies* CHD (congenital heart disease), CA (cancer), IBD (Inflammatory bowel diseases) 20. Describe signs and symptoms of arterial insufficiency.Postural Color Changes of Chronic Arterial Insufficiency.I f p a i n o r d i m i n i s h e d p u l s e s s u g g e s t a r t e r i a l i n s u ff i c i e n c y, l o o k f o r p o s t u r a l c o l o r c h a n g e s .Raise both legs, as shown at the right, to about 60° until maximal pallor of the feet develops—u s u a l l y w i t h i n a m i n u t e . I n l i g h t - s k i n n e d p e r s o n s , e i t h e r m a i n t e n a n c e o f n o r m a l c o l o r, a s s e e nin this right foot, or slight pallor is normal.
EXAMPLES OF ABNORMALITIESM a r k e d p a l l o r o n e l e v a t i o n s u g g e s t s a r t e r i a l i n s u f f i c i e n c y.Then ask the patient to sit up with legs dangling down. Compare both feet, noting the timerequired for:Return of pinkness to the skin, normally about 10 seconds or less• Filling of the veins of the feet and ankles, normally about 15 secondsThis right foot has normal color and the veins on the foot have filled. These normal responsessuggest an adequate circulation.EXAMPLES OF ABNORMALITIES • The foot above is still pale, and the veins are just starting to fill—signs of arterial i n s u ff i c i e n c y.Look for any unusual rubor (dusky redness) to replace the pallor of the dependent foot. Ruborm a y t a k e a m i n u t e o r m o r e t o a p p e a r. • Normal responses accompanied by diminished arterial pulses suggest that a good collateral circulation has developed around an arterial occlusion. • C o l o r c h a n g e s m a y b e d i ff i c u l t t o s e e i n d a r k e r - s k i n n e d p e r s o n s . I n s p e c t t h e s o l e s o f the feet for these changes, and use tangential lighting to see the veins.EXAMPLES OF ABNORMALITIES
P e r s i s t i n g r u b o r o n d e p e n d e n c y s u g g e s t s a r t e r i a l i n s u ff i c i e n c y ( s e e p . 4 9 8 ) . W h e n v e i n s a r eincompetent, dependent rubor and the timing of color return and venous filling are not reliablet e s t s o f a r t e r i a l i n s u ff i c i e n c y. p. 497 1. Pain - Intermittent claudication, progressing to pain at rest 2. Mechanism – Tissue ischemia 3. Pulses – Decreased or absent 4. Color – Pale, especially on elevation; dusky red on dependency 5. Temperature – Cool 6. Edema – Absent or mild; may develop as the patient tries to relieve rest pain by lowering the leg 7. Skin Changes – Trophic changes: thin, shiny, atrophic skin; loss of hair over the foot and toes; nails thickened and ridged 8. Ulceration – If present, involves toes or points of trauma on feet 9. Gangrene – May developEx: Arterial Insufficiency: Occurs in the toes, feet, or possibly areas of trauma (e.g., the shins).Surrounding skin shows no callus/ excess pigment, may be atrophic. Pain often is severe unlessneuropathy masks it. Gangrene, decreased pulses, trophic changes, foot pallor on elevation, &dusky rubor on dependency. p.498
1) Superficial Thrombophlebitis2) DVT3) Chronic Venous Insufficiency (Deep) 21. Describe signs and symptoms of venous insufficiency.Pain – Often painfulMechanism – Venous hypertensionPulses – Normal, though may be difficult to feel through edemaColor – Normal, or cyanotic on dependency Petechiae and then brown pigmentation appear withchronicity.Temperature – NormalEdema – Present, often markedSkin Changes – Often brown pigmentation around the ankle, stasis dermatitis, and possiblethickening of he skin and narrowing of the leg as scarring develops.Ulceration – If present, develops at sides of ankle, especially medially (medial malleolus).Gangrene – Does not develop.Chronic Venous Insufficiency (CRI)
CRI: Appears over medial and or lateral malleolus. Ulcer contains small, painful granulationtissue and fibrin; necrosis or exposed tendons are rare. Borders are irregular, flat, or slightlysteep. Pain affects quality of life in 75% of patients. Associated findings include edema, reddishpigmentation and purpura, venous varicosities, the eczematous changes of stasis dermatitis(redness, scaling, and pruritus), and at times cyanosis of the foot when dependent. Gangrene israre.Edema is soft, with pitting on pressure, occasionally bilateral. Look for brawny changes and skinthickening, especially near the ankle. Ulceration, brownish pigmentation, and edema in the feet.Arises from chronic obstruction and from incompetent valves in the deep venous system.Venous Disorders: 1) Atherosclerosis (Arteriosclerosis Obliterans) – a.intermittent claudicationb.Rest painp. 494 2) Acute Arterial Occlusion 3) Raynaud’s Disease and Phenomenon 22. Define the following symptoms of cardiac disease and identify why they are important in cardiac evaluation. a. Chest pain – often signals coronary heart disease. b. Shortness of breath – may represent dyspnea, orthopnea, or paraoxysmal nocturnal dyspnea. Complaint is common with patients with cardiac or pulmonary problems. c. Palpitations – involve unpleasant awareness of the heartbeat. Palpitations may result from irregular heartbeat, from rapid acceleration or slowing of the heart, or increased forcefulness of cardiac contraction. d. Orthopnea – dyspnea that occurs when patient is lying down and improves when patient sits up. Characteristic in left ventricular heart failure or mitral stenosis. e. Dyspnea on exertion (DOE) – uncomfortable awareness of breathing that is inappropriate to a given level of exertion. Common with cardiac/pulmonary problems.
f. Paroxysmal Nocturnal Dyspnea (PND) – describes episodes of sudden dyspnea and orthopnea that awaken the patient from sleep. Cmmon with left ventricular heart failure or mitral stenosis. g. Peripheral edema – accumulation of excessive fluid in the extravascular interstitial space. Causes may be cardiac (congestive heart failure, nutritional (hypoalbuminemia) or positional. Edema also occurs in renal and liver disease.Clinical Objectives 1. Obtain a relevant history for complaints relating to the cardiovascular system, to include the history of present illness (HPI), relevant past medical history (PMH) , social history (SH) and family history (FH) and review of system(s) (ROS) as outlined in Bickley and H&P Plus Booklet. 2. The student will demonstrate a complete and systematic examination of the cardiovascular system by completion of the following objectives: a. Identify the function of the bell and diaphragm of the stethoscope and give an example of a situation in which the use of each is appropriate. b. Identify signs of cardiac disease that can be noted on inspection of the patient. c. Inspect the anterior chest and identify the position of the apical pulse. d. Palpate the anterior chest and note the position and characteristics of the apical pulse. e. Identify on the chest wall the position of the Aortic, Pulmonic, Tricuspid, and Mitral area. f. Palpate each of the above areas and note the presence and characteristics of pulsations or the presence of thrills. g. Listen to the following areas with the diaphragm and bell of your stethoscope and identify the heart sounds heard and the characteristics of each: 1. Aortic 2. Pulmonic 3. Tricuspid 4. Mitral h. Listen with the bell to the tricuspid and mitral areas for the presence of a S3 or S4 i. Palpate the carotid pulse and note symmetry. j. Auscultate the carotid pulse and note the presence of a bruit. k. Inspect for jugular venous distension with the patient in a semi-fowler’s position. l. Demonstrate the proper location and technique for palpating the following pulses: 1. Radial – on the lateral flexor surface
2. Brachial – at the bend of the elbow just medial to the biceps tendon 3. Femoral – just below the inguinal ligament, midway between the anterior surface iliac spine and the symphysis pubis 4. Popliteal – an extension of the femoral artery that passes medially behind the femur, palpable just behind the knee. The popliteal artery divides into the two arteries perfusing the lower leg and foot 5. Dorsalis pedis – on the dorsum of the foot just lateral to the extensor tendon of the big toe 6. Posterior tibial – behind the medial malleolus of the ankle. An interconnecting arch between its two chief arterial branches protects circulation to the foot 7. Carotidm. Record rate, rhythm, character, and grading of pulses.n. Inspect for evidence of arterial or venous insufficiency.o. Demonstrate the proper method for checking for a Homan’s sign.p. Demonstrate the proper method for testing for ulnar artery patency (Allens test).q. Record a complete cardiovascular exam using appropriate terminology.