Prevalence of intra‐atrial reentrant tachycardia following mitral valve surgery: Relationship to surgical approach

Abstract

Background and Aim Mitral valve (MV) surgeries create electrophysiological substrates that give rise to postoperative arrhythmias. MV surgical procedures have been associated with macro‐ and microreentrant arrhythmogenic circuits, as well as circuits involving the atrial roof. It is not well understood why such arrhythmias develop; therefore, the aim of this study was to describe clinical and procedure characteristics associated with atrial arrhythmias in patients with prior MV surgery. Methods This retrospective chart review evaluated patients who had prior MV surgery and ablation procedures for atrial tachycardia between 2014 and 2018 (n = 20). Patients were classified into those exhibiting typical atrial flutter or another atrial tachyarrhythmia. Results Within the 20 patient cases reviewed, 30 arrhythmias were documented. Two‐thirds of arrhythmias were typical atrial flutter; the percent incidence of arrhythmias originating in the right atrial (RA) roof, around the right atriotomy scar, in the left atrium, and at the crista terminalis was 20%, 3%, 7%, and 7%, respectively. Nearly every case of RA roof flutter (n = 5/6) and most arrhythmias (n = 20/30) occurred in patients who had a transseptal approach during MV surgery. Voltage maps did not show clear differences in scarring between groups. Conclusion Results from this study suggest that an arrhythmogenic substrate for RA roof tachycardias is generated by transseptal approaches for MV surgery. This substrate is not clearly related to a surgical scar. These data suggest that other approaches should be considered for MV surgeries. Additionally, more research is needed to determine the mechanism for this nonscar‐related arrhythmia substrate.

Arrhythmias in Patients With Valvular Heart Disease: Gaps in Knowledge and the Way Forward

“…Although AF is the predominant arrhythmia after valvular surgery, macro-reentrant atrial tachycardia may result from surgical incisions ( 73 ). Right atrial macro-reentrant circuits, cavo-tricuspid or incisional, are frequent after MV surgery ( 46 , 74 ). Conversely, mitral annular flutter predominates after maze procedure ( 46 , 75 ).…”

Mitral annular flutter with epicardial coronary sinus conduit following mitral valve surgery

“…Despite positive outcomes in most patients, macroreentrant atrial arrhythmia is commonly encountered following maze procedure and is associated with an increased risk of mortality and morbidity. 1 , 2 Often refractory to conservative management, these recurrent arrhythmias necessitate catheter ablation for treatment. Although the perimitral scar from mitral valve surgery or prior ablation facilitates slow conduction around the mitral annulus, the musculature of the coronary sinus (CS) also serves as a critical component of the reentry circuit in a significant number of patients with atypical flutter.…”

Macro-reentrant atrial tachycardia after tricuspid or mitral valve surgery: is there difference in electrophysiological characteristics and effectiveness of catheter ablation?

“…Due to the complex substrate and coexistence of multiple reentries, catheter ablation of MATs in this scenario is often challenging and is associated with compromised long-term results [ 4 – 6 ]. In contrast to tricuspid valve surgery, mitral valve surgery involves inter-atrial septum incision and left atriotomy rather than right atriotomy, which might produce septal and left atrial MATs instead of right atrial MATs [ 7 – 9 ]. However, there is paucity of data regarding the difference in the electrophysiological characteristics of MATs after tricuspid or mitral valve surgery, and the effectiveness of MAT ablation in these patients has not been adequately investigated.…”