The Efficacy of Isochronal 3D Mapping-Based Ablation of Ventricular Arrhythmia

Surgical Endoepicardial Linear Ablation for Ventricular Tachycardia With Postinfarction Left Ventricular Aneurysm

This retrospective study evaluated the feasibility of surgical endoepicardial linear ablation for ventricular tachycardia in patients with postinfarction left ventricular aneurysm. Sixty-four patients with multivessel coronary artery disease and left ventricular aneurysm but no mural thrombosis of the aneurysm or valve disease were treated at our institution from March 2012 through July 2015. All underwent off-pump coronary artery bypass grafting and left ventricular aneurysm repair by linear plication. Twenty-three patients (35.9%) had ventricular tachycardia and underwent surgical endoepicardial linear ablation on the beating heart guided by epicardial substrate mapping with the Carto 3 system. The remaining 41 patients (64.1%) composed the no-ablation group. The effectiveness of surgical linear ablation in the ablation group was evaluated. Safety and clinical outcomes were evaluated and compared between the groups. The ventricular tachycardia recurrence rate in the ablation group was 17.4% in the immediate postoperative period and 23.8% at last follow-up (39 ± 21 mo). Early (<30-d) mortality rates were 8.7% in the ablation group and 4.9% in the no-ablation group (P=0.41); the respective late mortality rates were 19.1% and 18% (P=0.70). Multivariate Cox regression analysis indicated that preoperatively poor left ventricular function was an independent risk factor for early and late death in both groups. The groups were similar in terms of the need for postoperative mechanical circulatory support, intensive care unit stay, and cumulative survival rate. We conclude that, for carefully selected candidates, surgical endoepicardial linear ablation combined with off-pump coronary artery bypass grafting and left ventricular aneurysm linear plication is a feasible treatment for ventricular tachycardia with postinfarction left ventricular aneurysm.

Atypical Fast-Slow Atrioventricular Nodal Reentrant Tachycardia Using a Slow Pathway Extending to the Superoanterior Right Atrium

We report a case of atypical fast-slow atrioventricular nodal reentrant tachycardia (AVNRT) using a slow pathway variant extending to the superoanterior right atrium. The AVNRT diagnosis was confirmed by using standard electrophysiological criteria that exclude a diagnosis of atrial tachycardia and atrioventricular reentrant tachycardia. The earliest atrial activation during tachycardia was found in the superoanterior right atrium adjacent to the tricuspid annulus, where the first delivery of radiofrequency energy terminated and eliminated the inducibility of the tachycardia.

A Steam Pop Detected by Intracardiac Echocardiography During Catheter Ablation of the Left Ventricular Papillary Muscle

A 60-year-old female with premature ventricular contractions (PVCs) originating from the bottom of the posteromedial papillary muscle of the left ventricle underwent radiofrequency catheter ablation (RFCA) using an irrigated-tip catheter. During ablation of the PVCs, a loud steam pop was observed. Intracardiac echocardiography (ICE) revealed a growing, hyperechogenic intramyocardial microbubble formation around the catheter tip. The formation disappeared slowly and completely, leaving an endocardial laceration without pericardial effusion. ICE imaging is valuable during a difficult RFCA procedure, because ICE reveals the exact anatomical position of the catheter and thus allows rapid evaluation of the occurrence of steam popping and any possible subsequent complication.

Comparison of Outcomes of Mitral Valve Repair for Leaflet Prolapse with Advanced versus Mild/Moderate Myxomatous Degeneration

There is limited information on long-term outcomes of mitral valve repair for mitral regurgitation (MR) caused by different degrees of myxomatous degeneration. The aim of this study was to compare the surgical results of patients with advanced and mild/moderate myxomatous mitral valve degeneration (MVD). We identified 130 patients (25 advanced and 105 mild/moderate MVD patients) who underwent mitral valve repair for MR and were pathologically diagnosed as myxomatous degeneration. Follow-up was 100% complete (mean length, 5.1 ± 1.8 years). Survival differed significantly between the advanced and mild/moderate MVD groups (76.0 ± 9.7% versus 95.0 ± 5.4% at 8 years, P < 0.001). The univariate predictors of mortality were advanced myxomatous degeneration, recurrent MR, and early series (surgeries before 2011). The mild/moderate MVD group had higher freedom from a moderate or severe MR rate compared with the advanced MVD group (77.4 ± 4.5% versus 50.5 ± 10.2% at 7 years, P = 0.003). Multivariable Cox analysis revealed advanced myxomatous degeneration and residual MR as independent predictors of recurrent moderate or severe MR. A total of 25 patients (19.2%) had persistent atrial fibrillation (AF) after repair. In multivariate analysis, advanced myxomatous degeneration was found to be an independent predictor of postoperative persistent AF.In conclusion, the long-term outcomes of mitral valve repair in patients with advanced MVD are poorer than in those with mild/moderate MVD. Advanced myxomatous degeneration is an independent predictor of recurrent moderate or severe MR and postoperative persistent AF in MVD patients performing repair, which deserves more attention before and after surgery.