Post on 16-Jul-2015
By M.elkhatib CIN
First described by the French and Germans around 1900
a hypertrophied and non-dilated left ventricle in the absence of another disease
uncommon with occurrence of 0.02 to 0.2%
small LV cavity, septal hypertrophy (ASH), systolic anterior motion of the mitral valve leaflet (SAM)
• First reported by Seidman et al in 1989 HCM is a genetic condition which occurs as
autosomal dominant in 50%
5 different genes on at least 4 chromosome with over 3 dozen mutations◦ chromosome 14 (myosin)◦ chromosome 1 (troponin T)◦ chromosome 15 (tropomyosin)◦ chromosome 11 (?)
The sarcomeres in the heart replicate causing heart muscle cells to increase in size and the heart muscle to thicken
Causing myocardial disarray
75-90% of HCM patients have abnormal ECG Some abnormalities due to LVH include voltage
abnormalities - prominent Q waves, and signs of LA enlargement
Giant inverted T waves in the precordial leads characteristic of apical HCM
Classic findings Asymetrical septal hypertrophy Small LV cavity Enlarged LA For LVOTO - systolic anterior motion (SAM) of the
anterior or posterior mitral leaflet
Used when Hypertrophy is confined to the apex which may be difficult to image with echo
Contrast agents such as gadolinium may be used to identify regions of fibrosis and scarring
Cardiac cath helps exclude coronary disease as the cause of angina in patients who have risk factors for IHD.
It can also measure LV outflow tract gradient.
HCM can mimic other diseases such as hypertensive heart disease and amyloidosis
So many tests are conducted to diagnose
Differentiating hypertensive heart disease from HCM
A wall thickness of greater than 20mm Assymetrical septal hypertrophy More concentric in in hypertensive heart disease Sam can occur in both diseases - however in the
presence of LVOT and assymetry HCM more likely.
Differentiate between athletes heart and HCM Family History ECG patterns Assymetric Hypertrophy Small left ventricular cavity size LA enlargement Abnormal LV filling pattern
Annual mortality 3% in referral centersprobably closer to 1% for all patients
risk of SCD higher in children may be as high as 6% per yearmajority have progressive hypertrophy
clinical deterioration usually is slow
Young age (<30 years) “Malignant” family history of sudden death Gene mutations prone to SCD Sustained VT or SVT Recurrent syncope in the young Nonsustained VT (Holter Monitoring) Brady arrhythmias
Older adults with HCM have lower risk of SCD LV cavity of younger patients slightly different
shape Upper septal bulge and obstructive outflow tract
(older pts) Genetic sarcomere mutations are not the same in
children as adults
beta-adrenergic blockers amiodarone, sotolol ICD myectomy Alcohol Septal Ablation
The surgeon performs the operation by making an incision in the aorta and looking down at the septum through the aortic valve
The amount of septal heart muscle removed is variable depending on the patient.
Aortic regurgitation
LBBB
Stroke
VSD
Mortality 1.5% to 3.2%
HCM patients with defibrilators number of ICD discharges for ventricular arrhythmias.
Non-myectomy - 4.3%
Myectomy 0.24%
Mayo Clinic between 1992-2005.
Electrolyte monitoring Hydration - dehydration decreases pre-load and
increases HR this can increase the outflow tract gradient and obstruction
Vigilent monitoring for arrhythmias Emotional Support Dental Hygiene GTN/inotropes not mainstay treatment for HCM
so should be questioned.
Previous sudden death
High risk of sudden death
Relatively new technique
Performed during cardiac catheterisation
First performed at the Royal Brompton Hospital by Ulrich Sigwart in 1994
It is a minimally invasive procedure which avoids general aneasthesia and its associated complications
The long term benefits over Myectomy are still being debated
Alcohol solutionInjected into an arterySupplying the thickenedHeart muscleResulting in a Controlled MI
Patients generally experience a small amount of pain lasting about 30 Mins.
Length of stay in hospital is currently 2 days
Analgesics and mild sedatives can be given for alleviation of pain and anxiety
Relief of obstruction is noted immediately in the majority of cases
Clinical success is defined a 50% or more reduction in peak gradient and cardiac remodelling across the outflow tract, predicting continued improvement over 1- 2 yrs
Over 90% of patients experience a successful procedure with improvement in outflow gradient and mitral regurgitation.
Risk of re-entrant arrhythmias due to scarring
Risk of CHB - Pacing
RBBB
Mortality - 1.2% - 1.3%
Avoid most competitive sports (whether or not symptoms and/or outflow gradient are present)
Low-risk older patients (>30 yrs) may participate in athletic activity if all of the following are absent
Low-risk older patients (>30 yrs) may participate in athletic activity if all of the following are absent◦ ventricular tachycardia on Holter monitoring◦ family history of sudden death due to HCM◦ history of syncope or episode of impaired consciousness◦ severe hemdynamic abnormalities, gradient ≥50 mmHg◦ exercise induced hypotension◦ moderate or sever mitral regurgitation◦ enlarged left atrium (≥50 mm)◦ paroxysmal atrial fibrillation◦ abnormal myocardial perfusion