Left ventricular outflow tract obstruction in transthyretin amyloid cardiomyopathy: a case report on diagnostic and treatment challenges and role of alcohol septal ablation.

Abstract

Background: Transthyretin amyloid cardiomyopathy (ATTR-CM) is a restrictive cardiomyopathy caused by amyloid deposition in the myocardium. Its phenotypical overlap with hypertrophic cardiomyopathy, particularly in cases involving left ventricular outflow tract obstruction (LVOTO), challenges accurate diagnosis. Medical management of LVOTO in ATTR-CM is challenged by the opposing effects of beta-blockers and diuretics.

Case summary: A 79-year-old male with left ventricular hypertrophy and LVOTO presented with worsening dyspnoea. Full diagnostic work-up confirmed wild-type ATTR-CM. A conservative medical approach with diuretics and beta-blockers proved challenging. Alcohol septal ablation was successfully performed without major complication, resolving the LVOTO and improving symptoms.

Discussion: The diagnosis and management of ATTR-CM with LVOTO are complex. A thorough diagnostic approach is needed to avoid mismanagement. Diuretics and beta-blockers must be carefully balanced to achieve optimal clinical results. Alcohol septal ablation may be considered in patients with persistent symptoms and high LVOT gradients despite optimal medical therapy.