Surgical linear ablation for ventricular tachycardia with postinfarction ventricular aneurysm

A new classification of chronic postinfarction aneurysms of the left ventricle in patients with coronary artery disease

The article highlights the historical moments of how the concepts for the diagnosis and treatment of postinfarction aneurysms of the left ventricle were developed, and the possibilities of the main diagnostic methods. As a rule, patients with chronic postinfarction aneurysms of the left ventricle have severe damage to their coronary bed, requiring invasive correction (coronary artery stenting or coronary artery bypass grafting), which must be performed either before or during the intervention to eliminate the left ventricular aneurysm. A new classification of chronic postinfarction aneurysms of the left ventricle is proposed, which takes into account rather the type of myocardial blood supply and the severity of damage to the coronary bed, than the actual features of aneurysms. It determines the stages and tactics of treatment of patients with chronic postinfarction aneurysms of the left ventricle, focusing on the problem of coronary revascularization.

Impact of revascularization in patients with post-infarction left ventricular aneurysm and ventricular tachyarrhythmia

Background

Ventricular arrhythmia is a leading cause of cardiac death among patients with post‐infarction left ventricular aneurysm (PI‐LVA). The effect of coronary revascularization in PI‐LVA patients with ventricular tachyarrhythmia remains unknown. This study aims to investigate the impact of revascularization therapy on clinical outcomes in these patients.

Methods

A total of 238 PI‐LVA patients were enrolled, and 59 patients were presented with sustained ventricular tachycardia (VT) or ventricular fibrillation (VF). Patients were classified into 4 groups by treatment strategies (medical or revascularization) and the presence of VT/VF: group 1 (n = 57): VT/VF− and revascularization−; group 2 (n = 122): VT/VF− and revascularization+; group 3 (n = 34): VT/VF+ and revascularization+; and group 4 (n = 25): VT/VF+ and revascularization‐. The clinical outcomes were compared, and the primary endpoint was cardiac death or heart transplantation.

Results

Patients were followed up for 45 ± 16 months, and 41 patients (17.2%) reached the primary endpoint. Kaplan–Meier analysis showed that in VT/VF− patients, revascularization associated with higher cardiac survival compared with medical therapy (log‐rank p = .002), but in VT/VF+ patients, revascularization did not predict better cardiac outcome (log‐rank p = .901). Cox regression analysis revealed PET‐EF (HR 4.41, 95% CI: 1.72–11.36, p = .002) and moderate/severe mitral regurgitation (HR 2.32, 95% CI: 1.02–5.30, p = .046) as independent predictors of adverse cardiac outcome in patients with VT/VF.

Conclusion

PI‐LVA patients with VT/VF are at high risk of adverse cardiac outcome, and coronary revascularization does not mitigate this risk, although revascularization was associated with higher cardiac survival in PI‐LVA patients without VT/VF.

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.

Open chest epicardial and transapical endocardial substrate ablation for ventricular tachycardia with left ventricular aneurysm in a porcine model

BACKGROUND

Endo-epicardial radiofrequency catheter ablation (RFCA) of ventricular tachycardia (VT) as a first-line strategy has been shown to improve outcomes. This study sought to evaluate the feasibility and validity of open-chest epicardial and transapical endocardial substrate ablation for VT with left ventricular aneurysm (LVA) applying to routine cardiac surgery.

METHODS

Porcine models of LVA with VT were developed and were divided into a study group (RFCA from the epicardium via direct-view and endocardium via transapical access) and a control group (endocardial RFCA via retrograde transaortic access). Substrate-based mapping and ablation targeting abnormal potentials were performed under thoracotomy. Outcomes, including procedural success and acute freedom from VT, were analysed.

RESULTS

Twenty-four of 35 (68.57%) acute myocardial infarction (AMI) pigs developed LVA with VT in a 6-week survival period and were randomly divided into a study group (n=12) and a control group (n=12). All animals in the study group successfully underwent endocardial mapping and ablation by transapical access. The scar size of the endocardium and the left ventricular chamber volume were similar in the two groups. Acute freedom from VT in the study group was remarkably superior to that in the control group (88.33% vs. 58.33%, p=0.04).

CONCLUSIONS

Combined, direct epicardial and transapical endocardial substrate mapping and ablation appeared to be feasible and effective for treating VT with LVA under thoracotomy.