Cardiomyopathies Flashcards
Why is ECG used in DCM?
Mostly to rule out other things (sinus tachycardia, LBBB, arrhythmias)
What is the etiology of HCM?
Familial
Other management for RCM
CCB to improve diastolic compliance (CI in amyloid)
Anticoagultion
Consider transplant but some underlying diseases won’t let it
First line medication for DCM
ACE-i (reduce afterload by vasodilation to decrease BP)
Non-pharm management of DCM
Remove the underlying cause if possible
Limit activity based on functional status
Salt restriction <2-3 g/day
CPAP if sleep apnea
Management of stress CM
Just like acute MI so send to cath lab (but won’t find blockage)
Chemotherapy-induced DCM
Includes Adriamycin/Doxarubicin
Dose dependent and early detection is important
Treat the dysfunction and sxs
Get baseline echo to measure EF and monitor
Most common person for stress CM?
Post menopausal women
General signs of heart failure
Hypotension/tachycardia/tachypnea
Fatigue/weakness
Dyspnea (rest, exertional or at night) and orthopnea
Peripheral edema, elevated JVP, ascites
Sxs of HCM
Some are asymptomatic so found at death
Dyspnea on exertion mostly
Exertional angina
Fatigue, pre-syncope, palpitations
Mainstay for diagnosis of HCM
Echo with LV wall thickness > 15 mm
May have systolic anterior motion of mitral valve (measures obstruction gradient)
Etiologies of RCM
Infiltrative, storage diseases (hemochromatosis, glycogen storage disease), idiopathic, scleroderma, fibrosis from chemo, familial but rare here
What is the #1 cause of sudden death in competitive athletes 35 and younger?
Hypertrophic cardiomyopathy
Presentation of peripartum DCM
Mom is usually 36 wks gestation to 1 mo post partum
Usually transient dysfunction due to remodeling of LV so sxs probably better when not pregnant (dyspnea, hemoptysis, edema etc)
What is non-obstructive HCM?
Muscle hypertrophies in the wall and there is no blockage of the outflow tract
Initial management of HCM
Beta blockers
And exercise restriction obvi
Idiopathic DCM
Most common (50%)
Primary diagnosis for transplant
No cause obvi
Presentation of RCM
Right heart failure usually, angina, syncope, dyspnea
Prominent JVP, Kussmauls sign (increase in JVP with inspiration), maybe regurgitation murmur
What can RCM resemble?
Constrictive pericarditis (must differentiate)- scarring and consequent loss of normal elasticity of pericardial sac and impaired ventricular filling
In what diseases do you think about using Digoxin?
Afib, fatigue, dyspnea
When do you think of infectious DCM?
Presenting currently or previously with viral sxs (can be parasitic in Latin America-Chagas)
Most of the time when you clear the infection, the insult of the heart will improve
Factors that can worsen left ventricular outflow tract obstruction in obstructive HCM?
Tachycardia, hypovolemia, standing/valsalva (reduce cavity), + inotropes, diuretics, vasodilators
What is a cardiomyopathy?
Heart disorder when heart muscle is abnormal in absence of CAD, HTN, valvular disease or CHD
Risk factors of sudden cardiac death
Prior sustained ventricular tachycardia Non-sustained v tach Younger than 30 FH of sudden death due to this Massive LVF (>30 mm) Unexplainable syncope Brady arrhythmias
What do you see for diagnosis of peripartum DCM?
Increased BNP, echo shows EF<45
What happens to the septum in obstructive HCM?
Assymetrically hypertrophies
Pathophysiology of RCM
Non-dilated, rigid ventricles (deposits in muscle) that leads to diastolic dysfunction and restrictive filling
Preserved systolic function (HFpEF)
No hypertrophy usually
R and L atrial enlargement
Increased RA pressure leads to increased LA pressure and therefore forward failure (limited preload and SV, reduced CO and fatigue)
Gold standard of diagnosis infectious DCM
Endomyocardial biopsy (but very invasive)
What is stress/Takotsubo CM?
Transient LV systolic and diastolic dysfunction in absence of attributable CAD
Preceded by emotional/physical trigger usually
NE and epi released and stress heart so transient abnormality
Alcoholic DCM
Normal sxs of DCM with hx
Elevated LFTs
Tx of abstinence can lead to much improvement (if not then poor prognosis at 3-6 yrs)
Pathophysiology of DCM
Symmetric LV dilation, impaired LV systolic function and decreased EF (might involve RV)
Other medications for DCM
Diuretics (volume overload) B-blockers (decrease oxygen demand) Digoxin (+ inotrope, used in failure of other tx) Antiarrhythmics (amiodarone wwith afib) Antiocoagulation (afib, EF<30, thrombi) Implanted cardioverter defibrillator
Types of surgery for HCM
Indicated for symptomatic LVOT obstruction with advanced CHF refractory to medical therapy
Surgical septal myectomy
EtOH ablation
Mitral valve surgery
Distinguishing the murmur of HCM
Increases with valsalva and standing (v is decrease of preload and afterload, s is just preload)
Decreases with squat and isometic handgrip (squat is increase preload and afterload, i is just afterload)
*this is the same murmur in aortic stenosis but these maneuvers have a different effect
Potential exam findings in HCM
May be normal
Bifid carotid pulse (mitral valve coming close to septum), brisk radial pulse, audible S4, harsh crescendo-decrescendo murmur
Most common cause of RCM
Amyloidosis (infiltrative) which is abnormal amyloid protein in cardiac muscle
Other management of HCM
Non-dihydropyridine CCB
Diuretics but caution if significant obstruction
Manage arrhythmias
ICD implantation if high risk for SCD
Which is the most common CM?
Dilated
How do you see familial DCM?
Use the history of course
Seen in >50% of idiopathic pts
Cardiac protein antibodies in 30% of pts and in 20-30% of 1st/2nd degree relatives
Diagnostics for stress CM
Increased troponin and BNP (drop quicker then after MJ)
Look like MI on ECG
Decreased EF
Wall motion abnormalities on MRI
Presentation of stress CM
ACUTE ONSET
Present like acute coronary syndrome with sxs of HF
What is the leading cause of cardiac transplantation?
Dilated cardiomyopathy
Risk factor for alcoholic DCM
7-8 drinks/day > 10 yrs because alcohol is toxic to myoctyes
How do you rule out restrictive paricarditis?
Cardiac MRI
Mainstay of management for RCM
Low dose loop diuretics
Treat underlying cause obvi
Presentation of cardiac amyloidosis
Elevated JVP, hepatomegaly, ascites
Periorbital purpura wth HF- pathognomonic
How might DCM present?
Like heart failure
Mostly exertional intolerance with SOB and fatigue
Crackles, JVP, edema, regurgitation murmurs etc
Risk factors for peripartum DCM
> 30, African, multiparous, h/o preeclampsia (HTN, edema, proteinuria)/eclampsia (those with seizures)/postpartum HTM, maternal cocaine abuse, >4 wks of oral tocolytic to stop contractions
Pathophysiology of HCM
Diastolic filling abnormalities
Asymmetric septal hypertrophy
Small LV cavity
Maybe intramural vessel abnormalities and ischemia
Might be secondary to HTN or aortic stenosis
Criteria for familial DCM
+FH of DCM in 2+ relatives
Drug-related DCM
Causes myocarditis and toxic effects on myocardium
Cessation of cocaine can reverse dysfunction (it has hyperadrenergic affects on body)
Think of this when young person has sxs of HF for no reason
Long term management of stress CM
Depends on if LV dysfunction persists
ASA, BB and ACE-i until recovers
Anticoagulate for 3 mos with warfarin if thrombus
Most recover systolic function within 4 wks
What does it mean when RCM becomes symptomatic?
Usually a rapid decline (underlying dz progresses slowly)
Possible etiologies of DCM
Idiopathic, familial, infectious, alcoholism, peripartum, drugs, tachycardia-mediated, endocrine dysfunction, nutritional deficiencies
