Cardiomyopathies Flashcards
What are the two broad categories of cardiomyopathies?
- diastolic dysfunction
- systolic dysfunction
What’s happening to the heart muscle during diastolic dysfunction? Systolic dysfunction?
Diastolic Dysfunction -cannot relax -ventricles cannot relax -cardiac muscle gets bigger (hypertrophy)
Systolic dysfunction:
-loose floppy
-trouble contracting
(dilated)
What are the three functional classifications of cardiomyopathies? Which category does each belong to?
- ) Dilated/Congested/Idiopathic Cardiomyopathy= systolic dysfunction
- ) Hypertrophic/Idiopathic hypertrophic subaortic stenosis/Hypertrophic Obstructive cardiomyopathy = diastolic dysfunction
- ) Restrictive (Infiltrative) = diastolic dysfunction
How do you differentiate dilated systolic dysfunction from ischemia on echo?
-ischemia(CAD, Post MI) will just be a certain area thats not moving well, dilated the ENTIRE heart muscle is affected.
What does an ICD monitor?
rate and QRS complex
How do you differentiate aortic stenosis from hypertrophic diastolic dysfunction on PE?
-the murmur sounds the same initially, harsh blowing systolic murmur.
To differentiate you:
a.) have pt squat; increases blood return to the heart increasing volume, a softer murmur will be heard if IHSS/HCM/HOCM.
b.) pt lying down, push against their stomach as they resist your push, leads to increased pressure in thoracic cavity and decreased blood return to the heart, more turbulent flow, louder murmur if IHSS/HCM/HOCM.
Think water bottle example
Idiopathic dilated cardiomyopathy:
- definition
- what remodeling takes place?
- what causes dilated cardiomyopathy on a cellular level?
- effects on heart function
Def: disease of unknown etiology that principally affects the myocardium leading to systolic dysfunction.
Remodeling:
- LV dilation, stretch, and myocardium deterioration.
- increased heart size and weight
Cellular:
-hearts attempt to work hardder results in increasing levels of Ca2+ in cardiac cells which then activates an enzyme that switches on genes that cause heart enlargement.
Effects:
-impaired contractility decreases CO.
Dilated Cardiomyopathy
-who is more at risk of this?
African Americans and males have 2.5x increased risk
-most common age of dx is 20-50
Etiologies of Dilated Cardiomyopathy
- Idiopathic
- Myocarditis
- Ischemic Cardiomyopathy(CM)
- Infiltrative Dz
- Peripartum CM
- HTN
- HIV
- Connective Tissue Dz
- Substance abuse (drugs and alcohol)
- aortic regurgitation
- mitral valve regurgitation
Idiopathic Dilated Cardiomyopathy
- Clinical Presentation
- Dx
- Tx
CP: -heat failure sx -anginal chest pain -emboli -syncope -sudden cardiac death & arrhythmias -Systolic regurgitant murmur -S3 (fluid overload) Dx: -CXR: enlarged heart, biventricular enlargement, and pulmonary vascular congestion -EKG: LVH, left atrial enlargement, Q waves, poor r-wave progression, a-fib -Echo: confirms dx**, ventricular enlargement, increased systolic and diastolic volumes, decreased EF.
Tx:
- limit activity based on functional status
- salt restriction
- fluid restriction
- treat underlying cauase
- Meds: (Treat congestive sx)
- -ACEI/diuretics
- -Digoxin
- -hydralazine/nitrate combo (vasodilators)
- -antiocoagulants (d/t risk of thrombi)
- -anti-arrhythmics d/t risk of v-tach.
- consider transplant
Alcohol induced is what type of cardiomyopathy?
Is this reversible?
dilation, systolic dysfunction
-yes!!!
Peripartum Cardiomyopathy
- what category of cardiomyopathy?
- what is this?
- risk factors
- signs and sx
-dilated, systolic cardiomyopathy
What is this:
-ventricular dysfunction developing in the last month before delivery to 5 mo postpartum.
Risk factors:
- advanced maternal age
- African Americans
- multifetal pregnancies
- preeclampsia
- gestational HTN
Signs and Sx:
- resemble those dilated cardiomyopathy
- often sx are ignored b/c of dyspnea, swelling, and fatigue are normal sx during pregnancy*
Peripartum Cardiomyopathy
- dx
- tx
- outcomes of dz
Dx:
-echo, EKG
Tx:
- limit activity based on functional status
- salt restriction
- fluid restriction
- treat underlying cauase
- Meds: (Treat congestive sx)
- -ACEI/diuretics
- -Digoxin
- -hydralazine/nitrate combo (vasodilators)
- -antiocoagulants (d/t risk of thrombi)
- -anti-arrhythmics d/t risk of v-tach.
- consider transplant
Outcomes:
- 1/3 heart returns to normal in 6 mo
- 1/3 cardiomegaly persist and outcome is poor
- 1/3 heart returns to normal on maximal medical therapy.
Hypertrophic Cardiomyopathy
- how does this remodel the heart?
- how does this affect the function of the heart?
- cause
Remodel:
-septum is usual site for hypertrophy, but may affect entire ventricle.
Affects on the heart:
- abnormal compliance, impaired-diastolic relaxation andd filling.
- LV thickkness and small cavity size decrease wall tension for systolic contraction
- myocardial ischemia d/t increased muscle mass & O2 demand
Cause:
-hypertrophy develops as a compensatory response to sarcomeric dysfunction
Hypertrophic Cardiomyopathy
- sx
- PE findings
- Dx
- Tx
- Non-responders to Medical therapy tx
Sx:
- dyspnea on exertion
- angina
- palpitations
- syncope
- sudden death
PE Findings:
- palpable and audible S4
- harsh systolic ejection murmur across precordium and often mitral regurg murmr
Dx:
- Echo****
- EKG (LVH)
- CXR (usually normal)
Tx:
- avoid athletic/discourage rigorous exercise
- Holter x 48Hrs
- Vasodilators
- Inotropes
- Diuretics
- BETA BLOCKERS*** (slows HR and increased diastolic filling time)
non-responders to Medical therapy:
- Surgery (Myotomy/Myectomy)
- ICD***
- DDD pacemaker
- non-surgical septal reduction therapy….alcohol septal ablation.
