Predicting pacemaker implantation in cardiac amyloidosis: let's start with an ECG

Abstract

This article refers to 'Incidence and risk factors for pacemaker implantation in light chain and transthyretin cardiac amyloidosis' by A. Porcari et al., published in this issue on pages 1227-1236.Cardiac amyloidosis (CA) has been a hot topic in cardiology in the last years. Some key factors that explain this burst of interest are the development of imaging techniques with high sensitivity and specificity that have increased the diagnostic capacity, as well as the arrival of targeted and effective treatments. 1,2 However, the key point for diagnosing CA is to think about it, so clinical suspicion remains crucial. CA is a disease of red flags, 3 and cardiac conduction disturbances that require pacemaker (PM) implantation have been one of the best-known for decades. 4 The most accepted pathophysiologic mechanism for cardiac conduction system disease in CA is the infiltration of the conduction system by misfolded proteins, 5 as well as fibrosis of the sinoatrial node and atrioventricular conduction network. 4 Another potential mechanism could be direct toxic effect of amyloid fibrils, especially in light-chain (AL)-CA. 6 Current European Society of Cardiology pacing and cardiac resynchronization therapy guidelines do not include a specific therapeutic approach in patients with CA. 7 However, they consider CA as one of the underlying structural heart diseases in which bradycardia and cardiac conduction disturbances are more frequent. Thus, it is important to identify those patients at risk who could benefit from a closer clinical follow-up or a different approach, even considering implantable loop recorders in patients at a very high risk of PM implantation.