The disease progression of end-stage atrial cardiomyopathy over three decades: a case report.

Background: Atrial cardiomyopathy (AtCM) has drawn attention as the pathophysiology related to cardiovascular events such as atrial tachyarrhythmia, congestive heart failure, and embolic stroke. As the concept of AtCM is relatively recent, the long-term clinical course of AtCM has not been reported.

Case summary: Here, we describe a 78-year-old patient diagnosed with end-stage AtCM. He had started to visit our hospital due to paroxysmal atrial fibrillation (AF) and hypertrophic cardiomyopathy over three decades since the age of 45. During follow-up, he experienced cardiogenic embolism and pacemaker implantation due to sick sinus syndrome. At this time, he complained of palpitation due to AF and underwent catheter ablation. Regardless of de novo ablation, left atrial voltage mapping showed ultimately extensive scar in left atrium and pulmonary vein, suggesting that conventional AF ablation strategy was ineffective. From this finding, he was diagnosed with end-stage AtCM. In the review of the previous 12-lead electrocardiogram, P-wave amplitude was decreased, and PR duration was prolonged gradually. We performed only cavotricuspid isthmus ablation and ended the ablation session. After six months, he complained of dyspnoea on effort due to pacing-induced cardiomyopathy. Furthermore, before the cardiac resynchronization therapy with a defibrillator (CRT-D) upgrade, left atrial appendage thrombus was detected even under the administration of apixaban. After thrombolysis with warfarin, CRT-D upgrade the left ventricular ejection fraction was improved.

Discussion: In this case, the patient slowly developed end-stage AtCM and experienced multiple cardiovascular events related to severe AtCM. We should care for the disease progression of AtCM with vigilance.