11 18 2014 Cardiomyopathies Flashcards Preview

Cardiology M2 > 11 18 2014 Cardiomyopathies > Flashcards

Flashcards in 11 18 2014 Cardiomyopathies Deck (20)
Loading flashcards...

What are the 3 types of cardiomyopathies

- dilated
- restrictive
- hypertrophic


Dilated cardiomyopathy

Clinical signs?

ventricular chamber enlargement with impaired systolic contractile function
-- eccentric hypertension of ventricle

1. low forward cardiac output
2. fatigue
3. lightheadedness
4. exertion dyspnea (pulmonary congestion)

* increased risk for thrombotic events


Hypertrophic cardiomyopathy

abnormally thickened ventricular wall with abnormal diastolic relaxation; but usually intact systolic function


restrictive cardiomyopathy

abnormal stiffening of the myocardium leading to impaired diastolic relaxation but systolic contractile function is normal or near normal.


Causes of dilated cardiomyopathy

-viral myocarditis: immune related injury -- myocardial distraction and fibrosis


- toxic: alcohol (excessive) or doxorubin


Physical Examination of a person with dilated cardiomyopathy?

- cool extremities (owing to peripheral vasoconstriction)
-low arterial pressure
- tachycardia
- rales (pulm)
-S3 is common
-mitral valve regurgitation


Diagnosis of Dilated cardiomyopathy
1. chest radiograph
2. ECG
3. Echo

1. enlarged cardiac silhouette

2. atrial and ventricular enlargement, arrhythmias (atrial and ventricular: due to damage to muscle fibers)

3. 4 chamber cardiac enlargement with little hypertrophy


Treatment for dilated cardiomyopathy

TRANSPLANT (for those that qualify)

- treatment for heart failure
-treatment for arrhythmias
-treatment for thromboembolic events


Clinical findings for hypertrophic cardiomyopathy

- presentation is mid-20's
- young athletes
- Angina
- Syncope due to arrhythimas (structural abnormalities)
-dyspnea (due to mitral regurgitation)


Physical exam findings for hypertrophic cardiomyopathy

-S4 -- due to a non-compliant heart.
- obstruction: crescendo-descrescendo heard beast at the left lower sternal border
- Apex : holosystolic blowing murmur accompanying mitral regurgitation

- Valvular maneuver ("bear down") increase in inter thoracic pressure decreases venous return and reduces LV size = enhances obstruction murmur.


Causes of hypertrophic cardiomyopathy?

What does it do to the ventricle?

1. familial disease -- autosomal dominant
- mutation in sarcomere complex (beta-myosin heavy chain, cardiac troponins, and myosin binding protein C)

2. asymmetric left ventricular hypertrophy that is not caused by chronic pressure overload.
- systolic LV contractile function is vigorous but the thickened muscle is stiff.

MOST COMMON: asymmetric hypertrophy of the ventricular septum
- extensive disorganization of myocardial fiber pattern.

- reduces the compliance and diastolic relaxation of the chamber


Treatment for hypertrophic cardiomyopathy

-beta blockers
-calcium channel antagonists
-surgical therapy ( myomectomy) for patients whose symptoms do not respond adequately to medicine


Diagnostic fo hypertrophic cardiomyopathy

1. ECG
2. Echocardiography
3. cardiac catheterization

1. left ventricular and atrial enlargement with a Q wave that is prominent in inferior and lateral leads

2. degree of LVH

3. pressure gradient


Restrictive cardiomyopathy
1. how common are they
2. anatomy-- characterization
3. Cause?

1. less common that DCM and HCM

2. Characterized by abnormally rigid ventricles with impaired diastolic filling but usually normal or near normal systolic function.
* not necessarily thickened walls

3. Amyloidosis
* use congo red stain to see amyloid fibril deposits (misfolded proteins)



1. primary
2. secondary
3. hereditary
4. senile amyloidosis

1. caused by deposition of immunoglobulin light chains AL fragments secreted by a plasma cell tumor

2. presence of AA amyloid due to chronic inflammation ( ex. rheumatoid arthritis)

3. autosomal dominant

4. happens in elderly patients and they are scattered throughout the vascular system and other systems


Cardiac size on chest radiograph of restrictive cardiomyopathy

usually normal


ECG of restrictive cardiomyopathy will show what?

usually normal systolic contraction; "speckled" appearance in infiltrative disorders


Clinical findings of restrictive cardiomyopathies

- decreased CO
- Fatigue
- Systemic congestion = JVP, peripheral edema, palpable liver (tender)
- Arrhtyhmias : atrial fibrillation
- cardiac conduction block


Physical examination for restrictive cardiomyopathy

signs of right heart failure:
- Systemic congestion = JVP, peripheral edema, palpable liver (tender),
- Rales


Treatment for restrictive cardiomyopathy

phlebotomy and iron chelation therapy
- vasodialtors DO NOT WORK
- anticoagulants since intraventriuclar thrombus formation is common