Left Bundle Branch Area Pacing for Cardiac Amyloidosis With Ser43Asn Mutant Transthyretin: A Case Report.

Hereditary transthyretin (TTR) cardiac amyloidosis is a rare infiltrative cardiomyopathy. Involvement of the cardiac conduction system may lead to atrioventricular block. Left bundle branch area pacing (LBBAP) represents an emerging pacing strategy. We report a case of hereditary TTR amyloidosis with 2:1 atrioventricular block (second-degree), a wide QRS escape rhythm, and reduced ejection fraction, in which LBBAP improved symptoms and hemodynamic parameters. To our knowledge, this is the first documented case of Ser43Asn TTR amyloidosis managed with LBBAP.