Electrical cardioversion of atrial arrhythmias with cardiac amyloidosis in the era of direct oral anticogulants

Abstract

Aims Atrial fibrillation (AF)/atrial flutter is common during cardiac amyloidosis (CA). Electrical cardioversion (EC) is a strategy to restore sinus rhythm (SR). However, left atrial thrombus (LAT) represents a contraindication for EC. CA patients with AF/atrial flutter have a high prevalence of LAT. We aimed to evaluate EC characteristics, LAT prevalence and risk factors, and AF/atrial flutter outcome in CA patients undergoing EC, predominantly treated with direct oral anticoagulants (DOACs). Methods and resultsAll patients with CA and AF/atrial flutter referred for the first time to our national referral centre of amyloidosis for EC from June 2017 to February 2021 were included in this study. In total, 66 patients (median age 74.5 [70;80.75] years, 67% male) were included with anticoagulation consisted of DOAC in 74% of cases. All patients underwent cardiac imaging before EC to rule out LAT. EC was cancelled due to LAT in 14% of cases. Complete thrombus resolution was observed in only 17% of cases. The two independent parameters associated with LAT were creatinine [hazard ratio (HR) = 1.01; confidence interval (CI) = 1.00-1.03, P = 0.036] and the use of antiplatelet agents (HR = 13.47; CI = 1.85-98.02). EC acute success rate was 88%, and we observed no complication after EC. With 64% of patients under amiodarone, AF/atrial flutter recurrence rate following EC was 51% after a mean follow-up of 30 ± 27 months. Conclusions Left atrial thrombus was observed in 14% of CA patients listed for EC and mainly treated with DOAC. The acute EC success rate was high with no complication. The long-term EC success rate was acceptable (49%).

A review of recent advances in the diagnosis of cardiac amyloidosis, treatment of its cardiac complications, and disease-modifying therapies

“…Electrical cardioversion is also attempted; however, it is essential to rule out LA thrombus, and the recurrence rate of atrial fibrillation is high at 51%, as noted in a recent study. 28 A similar value holds for catheter ablations, with a recent study demonstrating an 80% recurrence rate at two years. 29 Anticoagulation with NOACs is indicated irrespective of the CHA2DS2-VASc score because of the risk of thrombus formation in CA due to its inherent risk of thrombogenicity beyond known risk factors.…”

2024 European Heart Rhythm Association/Heart Rhythm Society/Asia Pacific Heart Rhythm Society/Latin American Heart Rhythm Society expert consensus statement on catheter and surgical ablation of atrial fibrillation

“… 378 In a more recent observational study, LA thrombus was present in 14% of patients with cardiac amyloidosis referred for electrical cardioversion, despite prior anticoagulation, mainly with DOACs. 379 …”

Fibrilación auricular en amiloidosis por transtirretina

“…En una cohorte de 66 pacientes con FA llevados a cardioversión eléctrica, el 74% recibió anticoagulantes orales directos (DOAC, su sigla en inglés); el apixabán fue el más utilizado. En el seguimiento imagenológico se encontró una tasa de trombos auriculares izquierdos del 14% previo a la cardioversión eléctrica a pesar de tres semanas de terapia anticoagulante, sin documentarse diferencias estadísticamente significativas en cuanto a un DOAC en particular o uso de un DOAC comparado con un antagonista de la vitamina K (AVK) 38 . Otros estudios han reportado una tasa de persistencia de trombos en la aurícula izquierda de 28% antes de cardioversión eléctrica planificada en pacientes tratados con AVK o heparina 35 .…”

“…Otros estudios han reportado una tasa de persistencia de trombos en la aurícula izquierda de 28% antes de cardioversión eléctrica planificada en pacientes tratados con AVK o heparina 35 . Esta diferencia podría explicarse por un menor tiempo en rango terapéutico con el uso de AVK debido a las limitaciones para lograr niveles óptimos de INR en pacientes con AC 38 . Es pertinente, dada la alta tasa de trombosis auricular persistente, realizar estudios de imagen cardiaca previo a la cardioversión eléctrica 35,38 .…”

“…Esta diferencia podría explicarse por un menor tiempo en rango terapéutico con el uso de AVK debido a las limitaciones para lograr niveles óptimos de INR en pacientes con AC 38 . Es pertinente, dada la alta tasa de trombosis auricular persistente, realizar estudios de imagen cardiaca previo a la cardioversión eléctrica 35,38 .…”