Car 21 - Cardiomyopathies and Endocarditis Flashcards
What are the four most common bacteria in infective endocarditis?
Staphylococcus aureus. Viridans streptococci. Enterococci. Staphylococcus epidermidis.
What are the three types of cardiomyopathies? Which one is the most common of the three?
Dilated. Hypertrophic. Restrictive. Dilated is the most common of them.
What do you see in the histology of hypertrophic cardiomyopathy?
Disorganized hypertrophy of the left ventricle; tangled, disordered myosites. It also causes hypertrophy of the intraventricular septum.
What clinical findings do we find in hypertrophic cardiomyopathy?
Apical impulse enlarged and diffuse. S4 heart sound due to stiff ventricle. Systolic murmur due to outflow obstruction from the hypertrophied septum pushing the on the mitral valve; louder w/ valsalva (reduces preload that makes worsening of LV outflow tract obstruction) and softer w/ squatting (increasing the afterload decreases obstruction).
What is the most common cause of sudden death among younf healthy athletes in the USA?
Hypertrophic cardiomyopathy.
What is the treatment for hypertrophic cardiomyopathy?
Beta-blocker. Non-dihydropyridine calcium channel blocker (Verapamil). Restrict physical exertion and avoid volume depletion.
What is restrictive cardiomyopathy?
Deposition in myocardium disrupts diastolic function.
What are the causes of restrictive cardiomyopathy?
[LEASH] Loeffler syndrome. Endocardial fibroelastosis. Amyloidosis. Sarcoidosis. Hemochromatosis (Usually dilated by can cause restrictive).
What are the clinical findings of Dilated cardiomyopathy?
S3 heart sound. Apical impulse is displaced laterally.
What are 7 causes of Dilated Cardiomyopathy?
Chronic myocardial ischemia. Hemochromatosis. Doxorubicin, daunorubicin. Chronic cocaine and alcohol use. Wet beri beri (thyamine (B1) deficiency). Chagas disease (Trypanosoma cruzi). Myocarditis from Coxasackie B virus.
What is Myocarditis? What is the most common cause in the US and what do we find in histology?
Generalized inflammation of the myocardium (not resulting from ischemia). Most common cause of this in the US is from Coxsackie B virus. Histo: diffuse interstitial infiltrate of lymphocytes, with myocyte necrosis.
What cardiomyopathy would Chronic alcohol use cause?
Dilated cardiomyopathy.
What cardiomyopathy would Loeffler’s syndrome?
Restrictive cardiomyopathy.
What cardiomyopathy would T.cruzi cause?
Dilated cardiomyopathy.
What cardiomyopathy would sarcoidosis cause?
Restrictive.
What cardiomyopathy would cocaine cause?
Dilated cardiomyopathy.
What cardiomyopathy would cause S3 heart sound?
Dilated cardiomyopathy.
What cardiomyopathy would cause an S4 heart sound?
Hypertrophic cadiomyopathy.
What cardiomyopathy would cause a systolic murmur?
Hypertrophic cardiomyopathy.
What cardiomyopathy would cause sudden death?
Hypetrophic cardiomyopathy.
What cardiomyopathy would Beriberi cause?
Dilated cardiomyopathy.
What cardiomyopathy is hereditary?
Hypertrophic cardiomyopathy.
What cardiomyopathy would Doxorubicin cause?
Dilated Cardiomyopathy.
What cardiomyopathy would Coxsackie B virus cause?
Dilated cardiomyopathy.
What cardiomyopathy would amyloidosis cause?
Restrictive cardiomyopathy.
What cardiomyopathy would diffuse PMI cause?
Hypetrophic cardiomyopathy.
What is endocarditis?
Inflammation of the endocardium, usually the valves but can involve the septum or the cords. Characterized by lesions (vegetations) on the heart valves.
What is the most common site of endocarditis?
Mitral valve.
What is the most common site of endocarditis in drug users? What does this lead to?
Tricuspid is most common in IV drug users. Can lead to pulmonary infarcts.
What are Osler nodes?
Painful red nodules on fingers and toe pads. Seen in endocarditis.
What are Janeway lesions?
Painless erythematous macules on palms and soles. Seen in endocarditis.
What are Roth spots?
Retinal hemorrhages w/ clear central areas. Seen in endocarditis.
What are clinical symptoms of endocarditis?
Fever, chills, weakness, anorexia. Splinter hemorrhages in fingernails. Osler nodes, Janeway lesions, Roth spots. New regurgitation heart murmur or heart failure. Can cause embolisms or systemic immune reactions (glomerulonephritis, arthritis).
How do we diagnose Infective endocarditis?
Blood cultures. Echocardiogram (Transesophageal).
What would an endocardial infection by Stpahylococcus aureus look like?
30% of endocarditis cases. They cause an acute reaction and large vegetations on previously normal valves.
What would an endocardial infection by viridans streptococci look like?
20-30% of endocarditis cases. They cause a subacute reaction and smaller vegetations on valves that were already abnormal (bicuspid aortic valve, prosthetics). Associated w/ dental procedures.
What would an endocardial infection by Enterococcus look like?
10% of endocarditis cases. Some strains developing resistance to vancomycin (VRE).
What would an endocardial infection by Coagulase-negative staphylococci look like?
Staphylococcus epidermidis the most common. Causes 5-10% of endocarditis cases. Associated w/ IV drug users.
What is the name of endocardititis with vegetation on the heart valves but blood cultures are negative?
It is called culture negative endocarditis. [HACEK] Haemophilus. Actinobacillus. Cardiobacterium. Eikenella. Kingella.
What are the complications of endocarditis?
Embolic complications. Glomerulonephritis. Structural damage to infected valve. Valvular regurgitation or stenosis. Ruptured chordae tendineae. Suppurative pericarditis.
What is Libman-Sacks endocarditis?
Sterile vegetations caused by systemic lupus erythematosus. Occur on both sides of the valve simultaneously.
What is Marantic endocarditis?
Sterile vegetations caused by Metastatic cancer cells. Platelet-fibrin aggregates in patients w/ hypercoagulable states.
What are the differences b/w acute and subacte infective endocarditis?
Acute: Staphylococcus aureus, rapid onset (days), affects normal valves. Subacute: Viridans streptococci. Insidious onset (weeks to months). Affects previously damaged or congenitally abnormal valves.
An IV drug user presents w/ chest pain, dyspnea, tachycardia, and tachypnea. What is the most likely the cause?
Right-sided infective endocarditis w/ embolization into pulmonary arteries causing septic pulmonary emboli.
A patient in a MVA presents w/ chest pain, dyspnea, tachycardia, and tachypnea. What is the most likely cause?
Tension pneumothorax or fat embolus.
A post-op patient present w/ chest pain, dyspnea, tachycardia and tachypnea. What is the most likely cause?
Pulmonary embolism.
A young girl w/ congenital valve disease is given penicillin prophylactically. In the ER, infective endocarditis is diagnosed. What is the next step in her management?
Empiric IV vancomycin pending culture results.
RFF: Splinter hemorrhages under the fingernails.
Infective endocarditis.
RFF: Retinal hemorrhages w/ pale centers.
Roth spots (infective endocarditis).
RFF: Heart valve most commonly involved in infective endocarditis.
Mitral valve.
RFF: Heart valve most commonly involved in an IV drug user w/ infective endocarditis.
Tricuspid valve.
What are the symptoms of bacterial endocarditis?
[FROM JANE] Fever. Roth spots. Osler nodes. Murmur. Janeway lesions. Anemia. Nail-bed hemorrhage. Emboli.
