Clinical Approach To Cardiomyopathies Flashcards
3 primary categories of cardiomyopathies
Dilated cardiomyopathies (DCM)
Hypertrophic Cardiomyopathies (HCM)
Restrictive cardiomyopathies (RCM)
Acquired primary cardiomyopathies include what
Myocarditis
Peripartum (pregnant women w/ dysfunctional CO)
Tachycardia induced
Takotsubo “broken-heart” syndrome (stress induced cardiomyopathy)
Genetic primary cardiomyopathies include what
ARVD
HCM
Ion channel disorders
Left ventricular compaction
Mitochondrial myopathies
Mixed classification of primary cardiomyopathies
DCM
- primarily genetic, but can be acquired due to viruses
RCM
- primarily acquired but has some evidence that suggests genetic predisposition as well
Secondary causes of cardiomyopathies categories
Autoimmune/inflammatory
Endocrine dysfunctions
Infectious
Infiltrative disorders
Neuromuscular and storage disorders
Nutritional deficiencies
Toxic induced
Broad/shared clinical presentations of cardiomyopathies
Peripheral edema
Fatigue
Orthopnea (difficulty breathing while laying down)
Dyspnea on exertion
Paroxysmal nocturnal dyspnea
Syncope
Cardiac ischemia
Labs for cardiomyopathy diagnosis
CBC
CMP
BUN/creatinine levels
glucose levels
Lipid panel
TSH levels
Hypertrophic cardiomyopathy (HCM)
Essentially left ventricular hypertrophy without chamber dilation
- MOST COMMON or SECOND MOST COMMON primary cardiomyopathy*
- depends on publication, some suggest DCM is the most prevalent
Autosomal dominant mutations of genes that code for sarcomere proteins
Often asymptomatic and diagnosed via:
- family screening
- patient history
- auscultation of a murmur (specifically systolic)
- abnormal EGCs
Signs and symptoms of HCM (if present)
- Atypical chest pain (w/ POOP)
- history of family SCD
- systolic murmurs that increase in intensity w/ the valsalva maneuver
- the murmur sounds like a harsh crescendo->decrescendo heard over the recording but not in the carotids*
ECG abnormalities:
1) prominent abnormal Q waves
2) P wave biphasic and sometimes inverted
3) signs of LVH
4) Left atrial enlargement
5) Left axis deviation
6) Very peaked inverted T waves in V2-V4
Treatment of Hypertrophic Cardiomyopathy (HCM)
Main goals are to
- decrease exertional dyspnea
- decrease angina
- prevent SCD
General Tx:
- BBs = 1st line
- verapamil = 2nd line (if BBs cant be used)
- consult cardiology for consideration of septal ablation/ duel-chamber Pacing
Volume overload present
- consider diuresis via diuretics or ACE/ARBs
Obstruction present:
- add disopyraminde and remove vasodilators if present
What is the most common cause os SCD in athletes?
HCM
- more common in male athletes and non-whites
if a patient has the phenotype associated with HCM, they should be counseled to not continue intense competitive sports (33% of all SCDs in athletes are caused by HCM)
Risk factors for SCD w/ HCM
Family history of SCD in 1st degree relative
LV wall thickness is at least 30mm
Recent unexplained syncope
Prior cardiac arrest or sustained VT
Arrhythmogenic Right Ventricular Dysplasia/Cardiomyopathy (ARVD)
Disease of desmosomes characterized by fibrofatty infiltration of healthy myocardium
- leads to thinning and ballooning of the ventricular wall (usually right ventricle)
50% of cases are genetic within 1st degree
Signs of ARVD
ECG abnormalities:
- inverted T waves in V1-2
- epsilon waves in V1-2
Cardiac imaging
- RVH
- right ventricular aneurysms/ dilation
- reduced ejection fraction of RV
Clinical signs
- palpations
- syncope
Treatment of ARVD
Goals are to reduce arrhythmia and prevent SCD
Mild Tx:
- BBs = 1st line
- verapamil = 2nd line
- may use other antiarrhythmic agents if arrhythmias are present
- consult cardiology for potential surgery
Serious Tx
- catheter ablation of right ventricle
- implantable cardioverter defibrillator
- heart transplant
