Sudden death in a case of cardiac amyloidosis immediately after pacemaker implantation for complete atrioventricular block.

We report a patient with cardiac involvement associated with primary amyloidosis presenting marked left ventricular (LV) wall thickening, severely decreased systolic and diastolic function, and complete atrioventricular block (CAVB), who died suddenly of cardiac arrest caused by electro-mechanical uncoupling occurring immediately after permanent pacemaker implantation. Post mortem examination showed no procedural complications such as cardiac or venous perforation. The heart was densely infiltrated with amyloid fibrils, especially in the extracellular tissues surrounding the papillary vessels.