Cardiomyopathy Flashcards
What is the definition of cardiomyopathy?
heart disease resulting from a primary abnormality in the myocardium
List two types of surgical procedures to correct HOCM.
Open heart and excision - Alcohol ablation done through cardiac cath
What heart sound will likely be present with HOCM?
S4
List three medications which may be used both to prevent arrhythmia and ease symptoms with HOCM.
Diuretics
Beta blockers
Non-dihydropyridine CCB (verapamil or diltiazem)
Once a patient is diagnosed with HOCM what family counseling must be done?
Entire family must be screened for HOCM
Angina syncope and heart failure in a child likely represents ____________.
HOCM (Hypertrophic Cardiomyopathy)
Constrictive Cardiomyopathy occurs by what mechanism?
Pericardial sac constricts
Restrictive Cardiomyopathy occurs by what mechanism?
Deposition into or between the myocardial cells
What causes the sudden cardiac death in a HOCM patient?
Ventricular tachycardia that degenerates into ventricular fibrillation
What maneuver makes the HOCM murmur louder?
Valsalva or standing
What are the signs of HOCM on exam?
Apical lift
S4 gallop
Ejection murmur medial to apex
What is the treatment for dilated cardiomyopathy?
Same as systolic heart failure
Beta blocker, Loop Diuretic, ACE inhibitor
What are the three categories of cardiomyopathy and which is the most common?
Dilated (90%)
Hypertrophic
Restrictive
What do low ejection fraction and hypertrophic (HOCM) heart have in common?
Sudden death due to VT
What is the ejection fraction in a cardiomyopathy?
less than 40% (in the presence of increased left ventricular dimension)
Which chamber is most affected in cardiomyopathies?
Left ventricle
What chambers are affected (and how) in Dilated cardiomyopathy?
enlargement and dilation of all four chambers
What is the most common cause of non-ischemic DCM in the US?
chronic alcoholism
What is the second most common cause of non-ischemic cardiomyopathies? (#1 in other parts of the world)
viral myocarditis
What is damaged in DCM and what does it result in?
myocytes are injured and necrosis occurs with myocardial fibrosis when muscle cells fail they dilate
Does DCM have a systolic or diastolic dysfunction
systolic
What is the number one specific cause of dilated cardiomyopathy overall?
Ischemic cardiomyopathy (more than 60% of patients with heart failure have this)
What is seen histologically in DCM?
nonspecific abnormalities-variations in myocyte size\n-myocyte vacuolization-fibrosis and fat replace myocardium
How does alcoholism lead to DCM?
alcohol destroys microvilli brush border and leads to nutritional deficits (thiamine in particular) (glutamine helps regenerate)
alcohol is toxic to cardiac tissue-> myocyte death
What does the heart of someone with DCM resemble?
basketball
In which chamber are changes seen in HCM?
LVH w/o ventricular chamber dilation
What is HCM characterized by?
myocardial hypertrophy
abnormal diastolic filling
1/3 of cases
intermittent ventricular outflow obstruction
Which wall of the ventricle is more hypertrophic in HCM?
the septum of the L ventricle is larger than the free wall
What is seen histologically in HCM?
hypertrophy of myocardial fibers\n-interstitial fibrosis
Where is the mutation that leads to HCM located?
any one of several genes that encode proteins within the sarcomere
What is seen on an Echo for HCM?
hypertrophic septum and LV wall\n-small ejection fraction
What happens to the myocardium in restricted cardiomyopathy?
The myocardium is infiltrated with abnormal tissue-> impaired ventricular wall motion and abnormal contraction and relaxation
What are three causes of restrictive cardiomyopathy and which are the most common?
amyloidosis- most common\n \n-hemochromatosis-most common\niron overload(genetic)- kills cell\n \n-sarcoidosis
What population is most susceptible to RCM?
men of northern European descent
List 6 causes of restrictive cardiomyopathy
Amyloidosis Hemochromatosis Sarcoidosis Scleroderma Fibrosis Cancer
