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Cardiovascular overview Cardiac function and heart failure Valvular disease and endocarditis Pericardial diseases Coronary artery disease Arrhythmias and syncope Congenital heart disease Coagulation C 100 D Pressure (mm Hg) B 1. Which letter corresponds to the first heart sound? 2. Which letter corresponds to the second heart sound? 50 A E 0 Time Heart Failure: Definition Problem with the heart which results in inability to eject an adequate amount of blood to meet the demands of the body May be a problem with filling or with contraction Determinants of heart function Preload (LV end diastolic volume/pressure) Afterload (peripheral vascular resistance) Contractility (force of contraction) Anatomic classification of heart failure Pericardium Constrictive Coronary arteries Myocardial infarction Myocardium Dilated, pericarditis, tamponade hypertrophic, restrictive cardiomyopathies Valves Stenosis or regurgitation Heart failure Damage to LV results in dilatation and hypertrophy Activation of renin-angiotensin-aldosterone, sympathetic nervous system, antidiuretic hormone: Short term gain for long term pain Fluid retention Vasoconstriction Cellular growth and premature death Symptoms of heart failure Congestion Dyspnea Pulmonary edema Peripheral edema Low output Fatigue Signs of heart failure Sinus tachycardia Elevated JVP Enlarged apical impulse S3 Mitral regurgitation Edema Edema Increased venous hydrostatic pressure Heart failure, deep vein thrombosis or varicose veins, volume overload Obstructed lymphatics Eg. Following mastectomy with axillary node dissection Decreased plasma oncotic pressure Nephrotic syndrome, starvation “Leaky capillaries” Bee sting Cardiomyopathies Dilated: Myocardial damage leading to fibrosis and myocyte loss. LV is dilated and hypokinetic with LVEF < 40% Apex is enlarged and a third heart sound may be present Hypertrophic: Autosomal dominant condition with myocardial fiber disarray. Often disproportionate septal hypertrophy which can cause LV outflow tract obstruction because of systolic anterior motion of the mitral valve. Systolic murmur becomes louder when preload is decreased Restrictive: Infiltrative disorders such as amyloid cause diastolic LV dysfunction Heart Failure: Treatment Diuretics as needed for fluid retention Angiotensin converting enzyme inhibitors (eg enalapril): Decrease LV hypertrophy and dilatation. Prolong survival if LVEF < 40% Watch for hypotension with increasing dose Beta-blockers: Blunt toxic effects of sympathetic nervous system. Prolong survival in heart failure Spironolactone: Aldosterone inhibitor that also reduces myocardial collagen deposition and improves survival in severe heart failure Digoxin: Improves functional capacity An 80 year old man had a large anterior myocardial infarct 10 years ago and now presents with shortness of breath with mild exertion such as walking one block at a slow pace. On physical examination, blood pressure is 104/88 mm Hg, heart rate is 110 bpm. Jugular venous pressure is 10 cm above the sternal angle and there is pitting leg edema. The apical impulse is enlarged and there is a holosystolic mumur grade 2/6 at the apex. Which one of the following statements is false? A. Left ventricular afterload is decreased. B. Left ventricular preload is increased C. Left ventricular contractility is decreased D. Circulating catecholamines are elevated E. Angiotensin II levels are increased. Therapy for this patient should include all of the following except: A. Furosemide B. Enalapril C. Nifedipine D. Digoxin E. Spironolactone 1. CHF and diuretics 2. CHF and ACE inhibitor 3. CHF and NSAID with sodium retention Stroke 70 Volume (mL) 30 A F D C B G E 20 10 LV diastolic pressure (mm Hg) How does the patient shift on the Starling curve? Stroke 70 Volume (mL) 30 A F D ACE-I B C NSAID G Diuretic E 20 10 LV diastolic pressure (mm Hg) A 74 year old woman presents with peripheral edema. Which one of the following signs is most specific for a cardiac cause of edema? A. Apical systolic murmur B. Elevated jugular venous pressure C. Varicose veins D. Decreased volume of posterior tibial pulses E. Fourth heart sound Valvular disease Mitral regurgitation: Mitral valve does not close completely in systole and there is flow from LV to LA Systolic murmur at apex, third heart sound Increased left atrial pressure and LV diastolic pressure can be problem with LV, papillary muscles, chordae, leaflets. Mitral stenosis: Mitral valve doesn’t open completely in diastole Diastolic murmur at apex Increased LA pressure and normal LV diastolic pressure Usually a problem with commissural fusion secondary to rheumatic fever Valvular disease Aortic regurgitation: Aortic valve doesn’t close completely in diastole Bicuspid aortic valve or dilated aortic root that stretches the leaflets apart Aortic stenosis: Aortic valve doesn’t open completely in systole Bicuspid aortic valve or degenerative valve disease LV systolic pressure is higher than aortic systolic pressure Endocarditis Infection of the valves usually secondary to staphylococcus or streptococcus Predisposing conditions are valve disease and intravenous drug use Presents with fever, heart murmur and positive blood cultures Can lead to valve destruction and severe regurgitation with heart failure Treatment is iv antibiotics and valve replacement if heart failure develops Pericardial diseases Pericarditis: Inflammation of the pericardium. Pericardial friction rub may be present. Treated with NSAIDs. Pericardial tamponade: Fluid under pressure in the pericardial space. Heart can’t fill. Dyspnea and presyncope. Pulsus paradoxus and elevated JVP. Treatment is removal of fluid. Pericardial constriction: Fibrous encasement of the heart. Leads to heart failure because the heart can’t expand and fill. Elevated JVP and peripheral edema. Treatment is surgical pericardiectomy Diagnostic algorithm Chest pain Cardiac Non cardiac Ischemic Nonischemic GI Non GI Angina Unstable Angina Myocardial infarction Pericarditis Aortic Dissection GERD Spasm Peptic Ulcer Pneumothorax Pulmonary embolism Chest wall Panic attack When taking a history of chest pain ask Provoking and alleviating factors: When does it come on? What makes it better? Worse? Quality: What does it feel like? Region: Where is it? Does it go anywhere? Severity: Does it stop you from continuing what you’re doing? Timing: How does it start and how long does it last? CAD Angina: Atherosclerotic narrowing of coronary arteries results in myocardial ischemia when demand exceeds the supply Chest pain with exertion and relieved by rest or nitroglycerine Acute coronary syndrome Myocardial infarction: Necrosis which results from thrombotic occlusion of a coronary artery ECG: ST elevation followed by Q waves (total occlusion of coronary artery) or ST depression/T inversion (subtotal occlusion) Cardiac enzymes: Troponin, CPK MB are elevated Ischemia Increased myocardial oxygen demand Increased heart rate Increased afterload Increased contractility Decreased myocardial oxygen supply CAD Anemia Hypoxemia CAD: Treatment Stable angina: ASA and statins to prevent myocardial infarction. ACE inhibitors also improve survival if significant CAD. Beta-blockers, nitrates, calcium channel blockers to improve symptoms Myocardial infarction: ASA and thrombolytics (streptokinase, rtPA) or primary angioplasty to dissolve intra-coronary clot (ST elevation MI) Heparin, glycoprotein IIB/IIIA inhibitors in unstable angina or non ST elevation MI ASA, statins, beta-blockers and ACE-I to improve survival following MI Acute coronary syndrome (nonST elevation MI): ulcerated plaque with subocclusive thrombus What is the cause of chest pain in these patients? A 70 year old man with hypertension develops sudden onset of severe retrosternal pain. He is diaphoretic and a murmur of aortic regurgitation is present. A 20 year old man has severe,sharp precordial chest pain which is made worse by inspiration and relieved by sitting up. A rubbing sound is heard over the precordium. A 30 year old woman has sharp left chest pain which is reproduced by palpation of the fourth sternochondral joint. A 67 year old woman with diabetes has retrosternal chest discomfort with exertion that is relieved by rest. A 50 year old man has severe central chest heaviness for the past two hours. He is nauseated and diaphoretic. What is the most likely problem? Current management of ST elevation myocardial infarction includes all of the following except: A. Acetylsalicylic acid B. tPA or emergency percutaneous coronary intervention C. Beta-blocker D. Calcium channel blocker Schematic Diagram Of Cardiac Conduction Pathways Ca in K out Na in Absolute Refractory Period Na out K in Components Of The ECG B C A E D 1. Which letter represents ventricular depolarization? 2. Which letter represents potassium efflux from myocardial cells? 3. Which letter represents atrial depolarization? Mechanisms of arrhythmias Increased automaticity Re-entry Propagation of electrical impulse Unidirectional block Slowed retrograde conduction Reentry results in a self perpetuating fast rhythm Atria Atrial fibrillation or flutter AV node AV nodal re-entrant tachycardia Ventricles Ventricular tachycardia Palpitations Subjective sensation of abnormal heart beat Ask: Describe what you feel. Have you ever passed out or felt close to passing out? What is the cause of palpitations in this 25 year old athlete? What is the cause of palpitations in these patients? A 75 year old man comes to the ER because of chest pain. What is the appropriate treatment? While you are thinking about what to do he becomes unresponsive. Management of arrhythmias Slow AV node conduction: in SVT, atrial fibrillation/flutter Use Slow ventricular depolarization or repolarization to terminate ventricular tachycardia Use Calcium channel blocker , beta blocker, digoxin amiodarone, xylocaine, procainamide Prevent clot in left atrium: in atrial fibrillation Use warfarin Syncope Transient loss of consciousness Cardiac Arrhythmia Obstruction Vascular Neurocardiogenic: Most common Orthostatic hypotension Neurocardiogenic syncope •Young person •Response to fear or injury •Predisposing factors: • prolonged standing, venipuncture, heat, dental surgery, eye surgery •Pallor, nausea, sweating are associated •Reflex •Decrease preload and increased contractility •Stimulation of baroreceptors in LV •Afferent vagal fibers to medulla •Efferent outflow results in •increased vagal tone (bradycardia) •withdrawal of peripheral sympathetic tone (vasodilatation) •Resolves with lying down Which of these patients is most likely to have syncope? Congenital heart disease: Acyanotic Atrial septal defect: Communication between atria with LA to RA shunt. RA and RV dilated. Ventricular septal defect: Shunt from LV to RV with LA and LV dilatation. Patent ductus arteriosus: Shunt from descending aorta to pulmonary artery. LA and LV dilated. Congenital aortic stenosis: Presents with heart failure Coarctation of the aorta: Narrowing of the descending aorta at the site of ductus arteriosus. Heart failure and hypertension. Congenital heart disease: Cyanotic Tetralogy of Fallot: VSD and RV outflow tract or pulmonic valve stenosis with RV to LV shunt Transposition of the great arteries: Aorta arises from RV and PA from LV.Need PDA or ASD/VSD to survive. Eisenmenger’s syndrome: Severe irreversible pulmonary hypertension secondary to chronic volume overload with reversal of left to right intracardiac shunt Central cyanosis occurs commonly in patients who have which one of these congenital heart problems? A. Tetralogy of Fallot (pulmonic stenosis and ventricular septal defect) B. Bicuspid aortic valve C. Ventricular septal defect D. Atrial septal defect E. Patent ductus arteriosus Coagulation: What’s the diagnostic test? Warfarin therapy Disseminated intravascular coagulation Heparin therapy Thrombotic thrombocytopenic purpura von Willebrand’s disease Bleeding time PTT PT INR Fibrinogen Platelet count Coagulation: What’s the diagnostic test? Warfarin therapy Disseminated intravascular coagulation Heparin therapy Thrombotic thrombocytopenic purpura von Willebrand’s disease PT INR Fibrinogen PTT Platelet count Bleeding time Good luck!