Pharmacological Treatment of HCM

Question 1

First Line Therapeutic:

Answer 1

Beta Blockers- Guidelines suggest titrating up to maximal dose using non-vasoconstrictive beta-blockers-Class 1 level B evidence

Question 2

Evidence for Beta blocker use:

Answer 2

Frank et al, 1978:

• Small trial, non-RCT
• Nearly all HCM patients showed improvements in dyspnoea, chest pain, syncope, pre-syncope and palpitations with high dose propranolol
• But propranolol is not shown to have an impact on SCD prevention

Question 3

What if beta-blockers aren’t working or are contraindicated?

Answer 3

Use calcium channel blocker Verapamil titrated to the maximum tolerated dose (but needs close monitoring)-Class 1 Level B evidence

Question 4

Evidence for Verapamil Use:

Answer 4

Bonow et al, 1983:
Showed verapamil infusions can decrease outflow gradients where Beta-blockers are no longer working
Oral verapamil increased diastolic filling (so bigger CO to counteract LVOTO) after 1 weeks treatment which is an effect that beta blockers cannot reproduce

Question 5

What if beta blockers or calcium channel blockers aren’t enough?

Answer 5

Can add disopyramide to either on them. Disopyramide, titrated to maximum tolerated dose,e is recommended in addition to a ß-blocker (or, if this is not possible, with verapamil) to improve symptoms in patients with resting or provokedd LVOTO- Class 1 level B evidence
*Disopyramide inhibits sodium channels to prolong depolarisation

Question 6

Evidence for Disopyramide Use:

Answer 6

Sherrid et al, 2013:
Showed symptoms of patients treated with disopyramide showed improvement and reduced LVOTO gradients
Disopyramide did not alter survival