S7C59 - The cardiomyopathies, myocarditis, and pericardial disease

Question 1

cardiomyopathy defn

Answer 1

-abnormality in cardiac structure, impaired myocardial function or alteration in myocardial electrical properties

Question 2

dilated cardiomyopathy

Answer 2

• most common CM
• systolic and diastolic dysfxn, decreased LV contraction
• CHF, murmurs from incorrect valve closure, cardiomegaly, a fib, ventricular ectopy
• tx: ACEi and BB (carvedilol) improve survival

Question 3

some examples of primary cardiomyopathies

Answer 3

• HOCM
• conduction dz - long QT, brugada, short QT, idiopathic VF
• mixed - dilated cardiomyopathy
• acquired - myocarditis, takotsubo, peripartum CM

Question 4

secondary causes of Cardiomyopathies

Answer 4

• toxins: EtOH, chemo, ARV, cocaine, meth
• infiltrative - amyloid
• storage dz - hemochromatosis
• autoimmune - scleroderma, SLE, RA, dermatomyositis
• metabolic - electrolyte abn, endocrine
• neuromuscular d/o - musc dystrophy

Question 5

CM with systolic and diastolic dysfxn

Answer 5

• dilated CM - sx of CHF, c/p, regurgitant murmurs and ECG with LVH and poor R progression
• myocarditis - sx of fever, tachy, myalgias, c/p and non-specific ECG changes

Question 6

CM with diastolic dysfxn

Answer 6

HOCM - sx of SOBOE, c/p, palps, syncope, SEM and ecgLVH, large septal Q waves

Restrictive CM - low voltage QRS, a fib

Question 7

Myocarditis

Answer 7

• inflm of heart muscle
• causes:
• virus: coxsackie B, echovirus, influenza, EBV, HBV, HIV
• bacteria: corynebacterium diphtheriae, neisseria meningitidis, mycoplasma pneumoniae, beta-hemolytic strep, lyme dz
• sx: fever ,myalgia, h/a, tachy, c/p, friction rub
• tx: supportive

Question 8

HOCM

Answer 8

-hypertrophic CM
-dx: echo shows asymmetric septal hypertrophy
-LV or RV hypertrophy, asymmetric and usually involves the septum
-mutation in beta-myosin heavy chain
-a fib not well tolerated b/c heart relies on atrial contribuation to LV filling
-prominent a wave on JVP
-things that decrease LV filling and the distending pressure in the LV outflow tract or that increase the force of myocardial contraction accentuate teh murmur of HOCM -eg. valsalva
-hand gripping and squatting decrease the grip
ECG: LVH, LA enlargement, q waves
-syncope with exercise, soboe, c/p

dx: echo
tx: if c/p present - BB

Question 9

Restrictive CM

Answer 9

-etiology: idiopathic, amyloid, sarcoid, hemochromatosis, scleroderma, fibrosis
-restricted ventricular filling, normal systolic fxn
-elevated LV/RV end-diastolic pressure, normal LV systolic fxn, abnormal diastolic fxn
Sx: CHF, R sided heart failure
Tx: treat diastolic LV dysfxn with BB, CCB, or use steroids for sarcoid and blood draws for hemochrom.

Question 10

Hypertensive heart disease

Answer 10

-usually evidence of other end-organ damage

Question 11

Ichemic heart dz (ischemic CM)

Answer 11

-c/p usually

Question 12

Valvular heart disease

Answer 12

• rheumatic heart dz
• Ao stenosis
• bicuspid Ao valves

Question 13

Myocarditis

Answer 13

• usually young

- recent abrupt onset of symtpoms during or after a viral illness

Question 14

Causes of pericarditis:

Answer 14

• infx: viral, bacterial, fungal
• malignancy - leukemia, lymphoma, melanoma
• drugs - procainamide, hydralazine
• rheumatic dz (SLE, RA, scleroderma, polyarteritis nodosa, dermatomysositis)
• radiation
• post MI (Dressler)
• uremia
• myxedema

Question 15

Stages of ECG changes in pericarditis:

Answer 15

1. PR depression (II, aVF, V4-6), ST elevation (I, V5-6)
2. ST normalizes, T wave flattens
3. T wave inversion
4. T wave normalizes

Question 16

Constrictive pericarditis

Answer 16

• thickening of pericardium, prevents passive diastolic fillinf
• causes: post-op, TB, fungal, CRF
• Sx: exertional dyspnea, pedal edeam, heatomegaly, ascites, JVD, rapid y descent, kussmaul sign (inspiratory neck vein distention)
• Dx: ECG low voltages, inverted T, CXR usually normal, echo may show thickening/ cardiac CT, MRI are better