Cardiomyopathies Flashcards
1
Q
How common is cardiomyopathy in US?
A
- 3rd most common form of heart disease
- 2nd most common cause of adolescent heart disease
- pt will have CHF (usually presents at late stage)
2
Q
CXR finding of cardiomyopathy?
A
- cardiomegaly
3
Q
How are cardiomyopathies classified?
A
- primary: due to idiopathic process effecting the myocardium
- secondary: related to specific heart muscle disease
4
Q
Functional classification of cardiomyopathies?
A
- dilated:( congestive, DCM, IDC) - ventricular enlargement and systolic dysfxn
(alcohol, postpartum/peripartum, viral, genetic) - hypertrophic: (IHSS, HCM, HOCM) - inapprop. myocardial hypertrophy in absence of HTN or aortic stenosis
- restrictive: infiltrative (amyloidosis), abnormal filling and diastolic function, won’t have cardiomegaly
5
Q
Definition of IDC?
A
- disease of unknown etiology that principally affects the myocardium
- LV dilation and systolic dysfunction
- pathology: increased heart size and wt, ventricular dilation, normal wall thickness, heart dysfunction out of portion to fibrosis
6
Q
Dilated cardiomyopathy etiologies? pathophys?
A
- ventricles stretched and become flabby and myocardium deteriorates
- cause often unknown (autoimmune)
- drug toxicty (alcohol, cocaine, catecholamines, chemotherapeutic agents), hypothyroidism, inflammation of the heart in some cases - CHF
- hearts attempt to work harder results in increasing levels of Ca in cardiac cells, this activates Ca sensitive enzyme initiating cascade which switches on genest that cause heart enlargement
- because ventricular contractility is impaired, CO is poor and condition progressive worsens
7
Q
Most common etiology of DCM, what groups affected the most?
A
- systolic dysfxn and pump failure with low cardiac output
- 50% idiopathic
- african americans and males have 2.5x increased risk
- most common age of dx: 20-50 years
8
Q
characteristics of DCMs, what is seen on EKG and echo
A
- impaired systolic function leads to cHF
- dilation of one or both ventricles
- often idiopathic
- ethanol, chemotherapy
- peripartum
- ekg: nonspecific ST-T wave changes
- echo: show ventricular dilation
9
Q
How tod tell difference b/t dilated cardiomyopathy and dilated left ventricle due to severe CAD?
A
- usually post MI: local dysfunction
- dilated myopathy: global dysfxn
seen on echo!!
10
Q
Clinical presentations of idiopathic DCMs?
A
- HF sxs: 75%
- anginal CP: 8-20%
- emboli: 1-4%
- syncope: less than 1%
- sudden cardiac death and arrhythmias
- hear systolic regurg murmur, rales and edema
11
Q
Dx tests presentation of DCMs?
A
- CXR: enlarged heart, biventricular enlargement and pulm vascular congestion (kerley B lines)
- EKG: LVH, LAE, Q waves, poor R wave progression, and afib
- echo: confrms dx, ventricular enlargement, increased systolic and diastolic volumes, decreased EF
12
Q
Management of DCM?
A
- limit activity based on fxnl status
- salt restriction
- fluid restricition
- initiate medical therapy:
ACEI, diuretics
digoxin
hydralazine/nitrate combo
anticoag
anti-arrhythmicas - consider transplant: tx with meds for 6 months to see if progress: echo
13
Q
Goals of DCM therapy? diseases that can be tx?
A
- tx congestive sxs: diuresis
- ID diseases that can be tx:
CA
thyroid disease
hemochromatosis
sarcoidosis
infections
ETOH
drugs (chemo: doxirubicin)
peripartum
14
Q
Alchohol induced cardiomyopathy is how common? why does it occur, can it be tx?
A
- 3-4% of DCM
- more common in men
- etiology: direct toxic effects of ETOH, malnutrition
- maybe a genetic predisposition
- IT is reversible!!!! - stop drinking
15
Q
Workup of pt with dilated cardiomyopathy?
A
- hx focused on HF
- lab eval: EKG, CXR, echo and coronary angiography (CAD?)
- if echo shows dilated ventricles - and LVEF is less than 40% and no severe disease -
- if rapidly progressive sxs overe one month or new ventricular tachycardia or conduction abnorm and or suspected cause of myocarditis - get bx
- if not: tx with conventional HF meds - if no improvement in 1 week - consider bx
16
Q
What is peripartum cardiomyopathy, RFs?
A
- ventricular dysfxn developing in last month before delivery to 5 months postpartum
- rare
- RFs:
advanced maternal age, African American race, multifetal pregnancies, preeclampsia, gestational HTN - cause is uncertain
17
Q
Signs and sxs of peripartum cardiomyopathy?
A
- resemble those of dilated cardiomyopathy
- often sxs are ignored b/c of dyspnea, swelling and fatigue are normal sxs at end of pregnancy
(have to watch wt closely)
18
Q
Dx, and Tx of peripartum cardiomyopathy?
A
- dx: echo, EKG, and other tests of cardiac fxn
- tx: same as for dilated cardiomyopathy: diuretics, ACEI, anticoag
19
Q
3 possible outcomes of peripartum cardiomyopathy?
A
- 1/3 heart returns to normal in 6 months
- 1/3 cardiomegaly persists and outcome is poor
- 1/3 heart returns to normal on max lifelong medical therapy (diuretics, ACEI)
20
Q
Describe hypertrophic cardiomyopathy?
A
- inappropriate, asymmetric myocardial hypertrophy
- septum is usual site for hypertrophy
- cells will have bizarre appearance (sarcomeres are crossing the wrong way)
- familial (auto dominant) and sporadic forms
- hypertrophic cardiomyopathy with obstruction
21
Q
characteristics of HCM?
A
- pathological changes are of muscular hypertrophy assoc with fibrosis
- hypertrophied and non-dilated LV in absence of another disease, small LV cavity, uncommon disease
- abnormal compliance - impaired diastolic relaxation and filling - diastolic disorder
22
Q
Genetic abnormality hypothesis of HCM?
A
- hypertrophy develops as compensatory response to sarcomeric dysfxn
- normal myocytes react to excessice mechanical loads with altered patterns of gene expression and release of autocrine growth factors
- in HCM: normal systolic pressures sensed by abnorm myocyte as excessive load, intiating further hypertrophy
- in short term: increased LV thickness, and small cavity size decreases wall tension for systolic contraction
23
Q
Pathophys of HCM?
A
- systole: dynamic outflow tract gradient
- diastole: impaired diastolic filling, increased filling pressure
- Myocardial ischemia: increase muscle mass, and O2 demand, systolic compression of arteries
24
Q
Clinical features of HCM?
A
- sxs severity progresses with age
- HTN hx
- DOE most common initial sx
- angina - like CP, palpitations and syncope may also be present
- syncope
- sudden death - no sxs
25
What will you find on PE of HCM?
- apex will be localized
- palpable S4 (stiff noncompliant ventricle)
- harsh systolic ejection murmur across precordium - apex and heart base
- often mitral regurg murmur
26
HCM findings on Dx tests?
- doppler echo: LVH, systolic anterior motion of anterior mitral leaflet, asymmetric septal thickening (Most impt dx test)
- EKG: abnorm Q waves (Deep and narrow), LVH (30%)
CXR: usually normal (small cavity)
27
Management and screening of HCM?
- all first degree relatives: screening, echo/genetic counseling
- avoid competitive athletic/discourage rigorous exercise
- holterx48 hrs (sudden death comes from arrhythmias, afib to vtach)
28
Tx of HCM?
- maneuvers that decrease end diastolic volume (decrease venous return and afterload, and increase contractility) - valsalva and standing,
vasodilators (nitrates)
inotropes
diuretics (only if volume overload)
- BBs for longer diastolic filling time (slows HR)
29
Options for pts that don't respond to medical therapy?
- surgery (myotomy/myectomy) +/- MVR
- ICD (prevents sudden death)
- DDD pacemaker (decreases gradient)
- NSRT (non surgical septal reduction therapy - alcohol septal ablation - decrease gradient, first septal artery occluded with balloon cath and ETOH is injected distally)
30
Recommendations for athletic activity in HCM?
- avoid most competitive sports (whether or not sxs and or outflow gradient are present)
- low risk older pts (older than 30) may participate in athletic activity if all of following are absent:
- vtach on holter monitor
- family hx of sudden death due to HCM
- hx of syncope or episode impaired conscicousness
- severe hemodynamic abnorm, gradient of equal or greater than 50 mmHg
- exercise induced Hypotension
- mod or severe MR
- enlarged LA (greater than 50 mm)
- paroxysmal afib
- abnorm myocardial perfusion
31
Describe restrictive cardiomyopathy?
- least common of 3 major categories
- diastolic dysfxn: ventricular walls are excessively rigig and impede ventricular filling
- frequently accompanied by small degree of depressed contractility and EF
- myocardial fibrosis, hypertrophy, or infiltration due to variety causes, mostly idiopathic
- atria frequently become enlarged after chronic exposure to high filling pressure
32
Common causes of restricitive cardiomyopathy?
- deposition of abnormal substances in myocardium
- infiltrative disease: abnormal substance is largely b/t myocytes: amyloidosis, sarcoidosis
- endomyocardial: fibrosis or radiation
33
Clinical features of restrictive cardiomyopathy?
- exercise intolerance and dyspnea, dependent edema, ascites, anasarca, enlarged, tender, and often pulsatile liver (R sided sxs)
- thromboembolic complications: 1/3 of pts
- JVD, S3 and S4
34
Dx of Restrictive cardiomyopathy?
- CXR: signs of CHF w/o cardiomegaly
- EKG: nonspecific changes most likely
- Echo: thickened LV walls with normal or slightly decreased volume (rapid early ventricular filling, but late filling will be absent because no compliance)
- cath: R heart cath - filling pressure
35
Describe findings of amyloid heart disease?
- thickened, firm, rubbery ventricular muscle
- major diastolic dysfunction
- possible systolic dysfxn
- low voltage on EKG
- abnorm Q waves (look like MI)
- conduction disturbances, arrhythmias, not uncommon
- echo: thickened walls everywhere
- may find on rectal or gingival bx, may require myocardial bx
36
difference b/t restrictive and constrictive cardiomyopathy?
- hx provides impt clues to distinguish b/t the 2
- constrictive pericarditis: hx of TB, trauma, pericarditis, collagen vascular disorders
- restrictive cardiomyopathy: amyloidosis, sarcoidosis, hemochromatosis (iron deposits in skin)
37
Tx of restrictive cardiomyopathy?
- no satisfactory medical therapy
- drug therapy must be used with caution:
diuretics for extremely high filling pressures
vasodilators may decrease filling pressures (ACEIs)
- CCBs to improve diastolic compliance
38
When should we bx in cardiomyopathy?
- acute heart failure with sxs refractory to current medical management
- rapidly decreaseing LVEF with no clear etiology despite conventional therapy of HF
- HF with acutely worsening rhythm disturbances, particularly ventricular tachycardia
- new HF with conduction disturbances, particularly nodal block
- HF in setting of periph eosinophilia, rash and fevere
- HF in setting of hx of:
collagen vascular diseases: SLE, scleroderma, marfan
infiltrative and storage diseases: amyloid, sarcoid, hemochromatosis
- giant cell myocarditis (new tx)
- neoplasms
39
What conditions of restrictive cardiomyopathy warrant a bx that has effective therapy?
- cardiac allograft rejection
- sarcoidosis
- giant cell myocarditis
- hypereosinophilic syndrome
- endocardial fibroelastosis
- cardiac hemochromatosis
- lyme carditis
- some malignancies
