Two concomitant arrhythmias in a transplanted heart

Abstract

A 61-year-old man was admitted to our center complaining from palpitations due to frequent supraventricular extrasystoles (SVES). The patient had received an orthotopic heart-transplantation in 1989 due to dilated cardiomyopathy. In 2005, isthmus-dependent typical atrial flutter was documented and successfully ablated. Before the current admission, a 3-day Holter ECG recording was done which showed 15,000 SVES per day. There had been no signs of rejection and the left ventricular ejection fraction was 65%. On the 12-lead surface ECG a sinus rhythm with frequent SVES was noted with a P wave morphology closely resembling the sinus rhythm. Since the patient was highly symptomatic, we decided to perform an invasive electrophysiological study and ablation [1–3]. The patient gave written informed consent for the procedure of electrophysiology study and catheter ablation. After femoral vascular access, a steerable decapolar (Inquiry , Irvine Biomedical, Inc., Irvine CA, USA) and a non-steerable quadripolar catheter (Supreme , St. Jude Medical Inc., St. Paul MN, USA) were placed in coronary sinus and right ventricular apex, respectively. Electroanatomical mapping of right atrium was done using a 4-mm tip ablation catheter (Navi-Star, Biosense-Webster, Diamond Bar CA, USA) and the CARTO XP system (BiosenseWebster, Diamond Bar CA, USA). The surface ECG and the coronary sinus catheter showed sinus rhythm with frequent SVES; however, mapping of the posterior (recipient) right atrium showed an organized atrial arrhythmia, most probably an atypical atrial flutter with a cycle length of 170 ms which was electrically disconnected from the rest of the donor atria (Fig. 1). In the border zone between electrically isolated recipient and donor atria, both sinus rhythm and atypical atrial flutter were recorded at the same time on the mapping catheter (Fig. 1). We did not perform the activation mapping of the atypical atrial flutter in the recipient right atrium. Due to similar P wave morphologies of sinus rhythm and SVES, we decided to perform electroanatomical activation mapping during the sinus rhythm and SVES (Fig. 1) which showed a close proximity of sinus node and the ectopic focus of SVES (10 mm). An ablation was then performed successfully at the ectopic focus during which the SVES ceased and the patient remained in stable sinus rhythm during the rest of the hospitalization. During the procedure we did not note any signs of electrical conduction between the recipient and the donor heart although this has previously been described [4, 5]. The most common arrhythmia 2in heart transplant recipients is sinus node dysfunction leading to pacemaker implantation. Vaseghi et al. [6] studied recently the incidence, clinical course, and management of supraventricular tachycardia in 729 orthotopic heart transplant patients. The most common arrhythmia, atrial flutter, occurred in 9% of this cohort. Persistent or paroxysmal atrial fibrillation occurred in 7%, 57% in the perioperative period. Persistent or paroxysmal atrial fibrillation beyond the postoperative period was observed only in the presence of rejection or transplant vasculopathy. Other persistent or paroxysmal supraventricular tachycardias were seen in 47 patients (7%). Of these, 24 patients underwent EPS. Accessory and dual atrioventricular nodal pathways in the donor heart caused SVT in 3 patients. Macro-reentrant atrial tachycardia was seen in 7 patients, and isthmus-dependent atrial flutter occurred in 14 patients. In conclusion, the majority of supraventricular tachycardias in stable orthotopic heart F. Frogner A. Arya (&) C. Piorkowski G. Hindricks Department of Electrophysiology, Heart Center, University of Leipzig, Strumpellstrasse 39, 04289 Leipzig, Germany e-mail: dr.arasharya@gmail.com