Hypertrophic cardiomyopathy Flashcards
What defines hypertrophic cardiomyopathy (HCM)
left ventricular wall thickness>15 mm (1.5 cm) at any location
(can be interventricular septum) in absence of HTN or valvular heart dx
clinical presentation of hypertrophic cardiomyopathy
asymptomatic, develop dyspnea, orthopnea, palpitations and chest pain and dizziness and syncope
Can have exertional myocardial ischemia which can lead to ventricular arrhythmia and lead to sudden cardiac death
most common cause of sudden cardiac death in young athletes
hypertrophic cardiomyopathy
To lower risk of sudden cardiac death patients with definite or probable hypertrophic cardiomyopathy should (do what action?)
not participate in high intensity competitive sports
regardless of degree of wall thickness or LVOT obstruction or prior treatment.
when do we do alcohol septal ablation or surgical septal myectomy
HCM pts with severe LVOT obstructure (resting or valsalva gradient >50 mmHg) and heart failure symptoms that are refractory to medical therapy
why do we put in a cardioverter defribrillator (ICD)?
what are the criteria for placing one?
primary prevention for pts with risk factors for sudden cardiac death (LV wall thickness >30 mm or family hx of SCD due to HCM)
and secondary prevention for patients who survive an episode of sustained ventricular arrhythmia
how to treat patients with LVOT obstruction with symptoms of heart failure?
medical therapy with negative inotropic agents
BB and non- dihydropyridine ccb (verapamil and diltiazem), disopyramide)
beta blocker like metoprolol or bisprolol.
can add ACEi and diuretics are done cautiously and only if there’s heart failure and fluid overloaded. do want to avoid volume depletion.
dihydropyridine calcium channel blockers are
amlodipine and nifedipine
what meds should be avoided in patients who hypertrophic cardiomyopathy (HCM)?
diuretics
dihydropyridine calcium channel blockers (amlodipine and nifedipine)
vasodilators like ACEi.
These can decrease afterload and worsen LVOT obstruction and worsen symptoms
genetics of hypertrophic cardiomyopathy (HCM)?
autosomal dominant genetic cardiac dx 1 in 500.
who is high risk for sudden cardiac death with hypertrophic cardiomyopathy (HCM)
hx of cardiac arrest (spontaneous ventricular tachycardia)
family history of sudden cardiac death
syncope (recurrent or associated with exertion)
hypotensive BP after exercise
extreme left ventricular hypertrophy (>3 cm max septal wall thickness)
When do we put in ICD for primary and secondary prevention of sudden cardiac death in hypertrophic cardiomyopathy (HCM) pts?
when there’s 1 or more high risk factors.
general prognosis of hypertrophic cardiomyopathy (HCM)
it’s a heterogenous and variable clinical presentation and prognosis so most pts with HCM don’t have any symptoms and have normal life expectancy
incidence of sudden cardiac death in hypertrophic cardiomyopathy (HCM)
1% of HCM pts.
Difference between HCM and athlete’s heart
HCM: positive hx of HCM, EKG: prominent Q waves and LVH criteria. Left atrium is enlarged, small or normal LV cavity. LV ventricular wall thickness >15 mm and there’s abnormal left ventricular diastolic function
Athlete’s heart: no family history, EKG no Q waves or LVH criteria. Left atrial size normal. Left ventricular wall thickness <15 mm and normal LV diastolic function …has ONLY dilated left ventricular cavity
distribution of LVH hypertrophy can be anywhere >15 mm
True.
anywhere in LV wall can be enlarged. Hypertrophy must not explained by another cause like HTN or aortic stenosis.
Can have hypertrophy that’s variable and asymmetrical in septal, apical, left ventricular free wall or concentric hypertrophy.
so if someone has LV septal wall >18 mm that’s HCM even if posterior wall is 12 mm.
athlete’s heart is
physiological increase in left ventricular wall thickness, cavity size and mass that occurs in response to intense endurance training or exercise.
pt with HCOM presents with syncope what to do?
need implantable cardiac defibrillator.
due to high risk for ventricular arrhythmias
placed for people who have prior cardiac arrest, family history of sudden cardiac death
