HOCM

Question 1

Hypertrophic (obstructive) cardiomyopathy presentation

Answer 1

This young man has complained of palpitations whilst playing football.
Examine his cardiovascular system.

Question 2

Clinical signs of Hypertrophic (obstructive) cardiomyopathy

Answer 2

1. Jerky pulse character
2. Double apical impulse (palpable atrial and ventricular contraction)
3. Thrill at the lower left sternal edge
4. Auscultation:
   - -> Ejection systolic murmur (ESM) at the lower left sternal edge that radiates throughout the precordium.
   - -> A fourth heartsound (S4) is present due to blood hitting a hypertrophied stiff LV during atrial systole.
   - -> Dynamic ESM accentuated by reducing LV volume, e.g. standing from squatting or during a strain phase of Valsalva.
5. There may be associated mitral valve prolapse (MVP)
6. There may be features of Friedreich’s ataxia or myotonic dystrophy

Question 3

Auscultation in HOCM

Answer 3

1. Ejection systolic murmur (ESM) at the lower left sternal edge that radiates throughout the precordium.
2. A fourth heartsound (S4) is present due to blood hitting a hypertrophied stiff LV during atrial systole.
3. Dynamic ESM accentuated by reducing LV volume, e.g. standing from squatting or during a strain phase of Valsalva.
4. There may be associated mitral valve prolapse (MVP)

Question 4

Investigation for HOCM

Answer 4

1. ECG: LVH with strain (deep T‐wave inversion across precordial leads)
2. CXR: often normal
3. TTE:
   - - asymmetrical septal hypertrophy and systolic anterior motion of the anterior mitral leaflet across the LV Outflow Tract (LVOT) due to misalignment of septal papillary muscle,
   - - LVOT gradient (rest/exercise or dobutamine stress)
4. Cardiac MR: identifies apical HCM more reliably than TTE
5. Cardiac catheterization:
   - - gradient accentuated by a ventricular ectopic or pharmacological stress,
   - - identification of septals
6. Genetic tests: sarcomeric proteins mutation

Question 5

Management of HOCM

Answer 5

1. Asymptomatic: 
••••> Avoidance of strenuous exercise, dehydration and vasodilators 
2. Symptomatic and LVOT gradient >30 mm Hg 
••••> β‐Blockers 
••••> Pacemaker 
••••> Alcohol septal ablation 
••••> Surgical myomectomy 
3. Rhythm disturbance/high‐risk SCD 
••••> ICD 
4. Refractory: 
••••> Cardiac transplant 
@ Genetic counselling of first‐degree relatives (autosomal dominant inheritance)

Question 6

Prognosis of HOCM

Answer 6

i. Annual mortality rate in adults is 2.5%
ii. Poor prognosis factors:
1. Young age at diagnosis
2. Syncope
3. Family history of sudden death
4. Septal thickness > 3 cm