Alcohol septal ablation for obstructive hypertrophic cardiomyopathy

Hypertrophic cardiomyopathy is an inhered heart disease characterised by a thickened heart muscle, common in 1:500 persons. Obstruction of blood flow in the heart due the thickened heart muscle can occur and cause dyspnoea. A heart surgeon can cut away part of the thickened muscle (myectomy). With alcohol septal ablation (ASA), an interventional cardiologist creates a small myocardial infarction by injecting alcohol in a side branch of the coronary arteries. Both techniques locally reduce the thick myocardium and alleviate obstruction and dyspnoea.

In the current research mortality was found higher, when residual obstruction was present after ASA and when infarctions were larger. A higher dosage of alcohol was not more effective. A too distally chosen side branch for alcohol injection was ineffective for relief of the obstruction. With CMR research distal compared to basal myocardial infarction location, was less effective for relief of the obstruction.
Young (43 years average) compared to older patients have good results after ASA and a lower complication rate. Both ASA and myectomy are effective for symptom improvement and have a good survival rate. Though complications are less common and in-hospital stay was shorter after ASA, second ASA procedure and pacemaker implantations were more common.
In conclusion: both ASA and myectomy are safe and effective procedures for treatment of obstructive HCM. The interventional cardiologist should strive for a small and basal located myocardial infarction. ASA is less invasive in nature, but is offset by a higher chance for a pacemaker implantation and a second ASA procedure.