Snapshot A 16-year-old boy presents to his pediatrician for syncope. In the past few months, he had syncopal episodes when he played football, soccer, and sprinting. His family history includes sudden cardiac death in several relatives. An echocardiogram shows marked hypertrophy and abnormal systolic anterior leaflet motion of the mitral valve. (Hypertrophic cardiomyopathy) Introduction Clinical definition cardiomyopathies intrinsically affect the myocardium, leading to systolic or diastolic dysfunction these do not include changes in the myocardium secondary to hypertension, coronary artery disease, or valvular disorders types of cardiomyopathies dilated cardiomyopathy (most common) restrictive/infiltrative cardiomyopathy hypertrophic cardiomyopathy (obstructive vs non-obstructive) Cardiomyopathies Dilated Restrictive/Infiltrative Hypertrophic Etiology ABCD Alcohol abuse Beriberi (wet) Coxsackie B viral myocarditis Chronic Cocaine use Chagas disease Doxorubicin toxicity Hemochromatosis Sarcoidosis Titin mutation Peripartum cardiomyopathy Radiation therapy Loffler endocarditis (with endomyocardial fibrosis and eosinophilic infiltrate) Endocardial fibroelastosis (in children) Amyloidosis Sarcoidosis Scleroderma Troponin mutation Hemochromatosis Familial (most common) autosomal dominant mutations in sarcomere proteins (β-myosin heavy chain = myosin binding protein C > tropomyosin = troponin I/C - in order of frequency of mutations) Idiopathic Pathology Systolic dysfunction from ↓ contractility and ↓ ejection fraction Eccentric hypertrophy (sarcomeres added in series) Stiff myocardium causes diastolic dysfunction Preserved left ventricular systolic function Diastolic dysfunction from ↓ compliance of left ventricle Septal hypertrophy Majority of cases are obstructive (hypertrophic obstructive cardiomyopathy) Concentric hypertrophy (sarcomeres added in parallel) Clinical presentation Congestive heart failure S3 sound Systolic murmur Progressive heart failure Sudden cardiac death S4 sound (and others can present with S3) + Kussmaul sign Syncope with activity Sudden cardiac death (especially in young athletes) S4 sound Systolic murmur without radiation ↑ with Valsalva and standing up ↓ with hand grip and squatting Diagnostic studies Chest radiography ballooning of heart Echocardiogram dilated ventricles and ↓ ejection fraction Electrocardiogram bundle branch block Chest radiography cardiomegaly and pulmonary congestion Echocardiogram thickening of all structures diastolic dysfunction Endomyocardial biopsy the most accurate test for etiology Electrocardiogram may have low voltages Echocardiography normal ejection fraction hypertrophy mitral regurgitation decreased end systolic volume and end diastolic volume Electrocardiogram left ventricular hypertrophy Histology tangled and disoriented myofibrils Treatment Angiotensin-converting enzyme inhibitors β-blockers Spironolactone Automatic implantable cardioverter/defibrillator Biventricular pacemaker Treat underlying condition Diuretics Heart transplant Avoid athletic activities β-blockers Non-dihydropyridine calcium channel blockers Implantable cardioverter/defibrillator
QUESTIONS 1 of 11 1 2 3 4 5 6 7 8 9 10 11 Previous Next Sorry, this question is for PEAK Premium Subscribers only Upgrade to PEAK Sorry, this question is for PEAK Premium Subscribers only Upgrade to PEAK Sorry, this question is for PEAK Premium Subscribers only Upgrade to PEAK (M1.CV.15.1) A 19-year-old basketball player unexpectedly collapses on the court. Several minutes later he returns to consciousness and is able to continue playing. This has happened several times before with similar outcomes. He had no significant past medical history. Which of the following is most likely to be found in this patient? Tested Concept QID: 100517 Type & Select Correct Answer 1 Atheromatous plaque rupture 0% (0/73) 2 Coagulation necrosis with loss of nuclei and striations 1% (1/73) 3 Septal hypertrophy 86% (63/73) 4 Postductal coarctation of the aorta 5% (4/73) 5 Cardiac myxoma 5% (4/73) M 2 Question Complexity C Question Importance Select Answer to see Preferred Response SUBMIT RESPONSE 3 Review tested concept (M1.CV.14.219) A 19-year-old Caucasian male collapsed from sudden cardiac arrest while playing in a college basketball game. Attempts at resuscitation were unsuccessful. Post-mortem pathologic and histologic examination found asymmetric left ventricular hypertrophy and myocardial disarray. Assuming this was an inherited condition, the relevant gene most likely affects which of the following structures? Tested Concept QID: 100735 Type & Select Correct Answer 1 Cardiac cell sarcomere proteins 95% (63/66) 2 Membrane potassium channel proteins 2% (1/66) 3 Ryanodine receptors 0% (0/66) 4 Autoimmune beta-cell antibodies 2% (1/66) 5 Membrane sodium channels 2% (1/66) M 2 Question Complexity D Question Importance Select Answer to see Preferred Response SUBMIT RESPONSE 1 Review tested concept (M1.CV.13.20) A 49-year-old man presents to his physician complaining of weakness and fatigue. On exam, he has significant peripheral edema. Transthoracic echocardiogram is performed and reveals a preserved ejection fraction with impaired diastolic relaxation. A representative still image is shown in Figure A. Which of the following is likely the cause of this patient's symptoms? Tested Concept QID: 100536 FIGURES: A Type & Select Correct Answer 1 Previous treatment with doxorubicin 6% (4/65) 2 Hemochromatosis 48% (31/65) 3 Heavy, long-term alcohol consumption 18% (12/65) 4 History of myocardial infarction 9% (6/65) 5 History of a recent viral infection 17% (11/65) M 1 Question Complexity E Question Importance Select Answer to see Preferred Response SUBMIT RESPONSE 2 Review tested concept (M1.CV.13.103) An 18-year-old African-American male presents to his family physician for a routine sports physical. He has a family history of sudden death at a young age. Upon physical examination the physician appreciates a systolic murmur. The intensity of the murmur increases when performing a valsalva maneuver. The physician refers the patient for an EKG, which is attached. What is the most likely cause of this murmur? Tested Concept QID: 100619 FIGURES: A Type & Select Correct Answer 1 Aortic valve stenosis 6% (5/77) 2 Mitral stenosis 1% (1/77) 3 Tricuspid stenosis 3% (2/77) 4 Hypertrophic cardiomyopathy 90% (69/77) 5 Benign systolic flow murmur 0% (0/77) M 1 Question Complexity E Question Importance Select Answer to see Preferred Response SUBMIT RESPONSE 4 Review tested concept (M1.CV.13.140) A 66-year-old female with a past medical history significant for hypertension and breast cancer that is in remission after chemotherapy, presents to her primary care physician complaining of progressive dyspnea, decreased exercise tolerance, and paroxysmal nocturnal dyspnea. On chest auscultation you note an S3. A chest radiograph and echocardiogram are shown in Figure A. Which of the following medications is likely responsible for the patient's current presentation? Tested Concept QID: 100656 FIGURES: A Type & Select Correct Answer 1 Lisinopril 2% (1/65) 2 Digoxin 5% (3/65) 3 Cytarabine 5% (3/65) 4 Hydrochlorothiazide 3% (2/65) 5 Doxorubicin 86% (56/65) M 1 Question Complexity D Question Importance Select Answer to see Preferred Response SUBMIT RESPONSE 5 Review tested concept Sorry, this question is for PEAK Premium Subscribers only Upgrade to PEAK Sorry, this question is for PEAK Premium Subscribers only Upgrade to PEAK (M1.CV.12.12) A 12-year-old girl with an autosomal dominant mutation in myosin-binding protein C is being evaluated by a pediatric cardiologist. The family history reveals that the patient's father died suddenly at age 33 while running a half-marathon. What was the likely finding on histological evaluation of her father's heart at autopsy? Tested Concept QID: 100528 Type & Select Correct Answer 1 Myocyte disarray 87% (62/71) 2 Amyloid deposits 6% (4/71) 3 Eosinophilic infiltration 0% (0/71) 4 Wavy myocytes 4% (3/71) 5 Viral particles 0% (0/71) M 2 Question Complexity E Question Importance Select Answer to see Preferred Response SUBMIT RESPONSE 1 Review tested concept