Catheter Ablation of Ventricular Arrhythmia in Patients With an Implantable Cardioverter-Defibrillator: A Systematic Review and Meta-analysis

Competing risks of monomorphic vs. non-monomorphic ventricular arrhythmias in primary prevention implantable cardioverter-defibrillator recipients: Global Electrical Heterogeneity and Clinical Outcomes (GEHCO) study

AIMS

Ablation of monomorphic ventricular tachycardia (MMVT) has been shown to reduce shock frequency and improve survival. We aimed to compare cause-specific risk factors for MMVT and polymorphic ventricular tachycardia (PVT)/ventricular fibrillation (VF) and to develop predictive models.

METHODS AND RESULTS

The multicentre retrospective cohort study included 2668 patients (age 63.1 ± 13.0 years; 23% female; 78% white; 43% non-ischaemic cardiomyopathy; left ventricular ejection fraction 28.2 ± 11.1%). Cox models were adjusted for demographic characteristics, heart failure severity and treatment, device programming, and electrocardiogram metrics. Global electrical heterogeneity was measured by spatial QRS-T angle (QRSTa), spatial ventricular gradient elevation (SVGel), azimuth, magnitude (SVGmag), and sum absolute QRST integral (SAIQRST). We compared the out-of-sample performance of the lasso and elastic net for Cox proportional hazards and the Fine-Gray competing risk model. During a median follow-up of 4 years, 359 patients experienced their first sustained MMVT with appropriate implantable cardioverter-defibrillator (ICD) therapy, and 129 patients had their first PVT/VF with appropriate ICD shock. The risk of MMVT was associated with wider QRSTa [hazard ratio (HR) 1.16; 95% confidence interval (CI) 1.01-1.34], larger SVGel (HR 1.17; 95% CI 1.05-1.30), and smaller SVGmag (HR 0.74; 95% CI 0.63-0.86) and SAIQRST (HR 0.84; 95% CI 0.71-0.99). The best-performing 3-year competing risk Fine-Gray model for MMVT [time-dependent area under the receiver operating characteristic curve (ROC(t)AUC) 0.728; 95% CI 0.668-0.788] identified high-risk (> 50%) patients with 75% sensitivity and 65% specificity, and PVT/VF prediction model had ROC(t)AUC 0.915 (95% CI 0.868-0.962), both satisfactory calibration.

CONCLUSION

We developed and validated models to predict the competing risks of MMVT or PVT/VF that could inform procedural planning and future randomized controlled trials of prophylactic ventricular tachycardia ablation.

CLINICAL TRIAL REGISTRATION

URL:www.clinicaltrials.gov Unique identifier:NCT03210883.

Machine-Learning-Based Prediction of 1-Year Arrhythmia Recurrence after Ventricular Tachycardia Ablation in Patients with Structural Heart Disease

BACKGROUND

Ventricular tachycardia (VT) recurrence after catheter ablation remains a concern, emphasizing the need for precise risk assessment. We aimed to use machine learning (ML) to predict 1-month and 1-year VT recurrence following VT ablation.

METHODS

For 337 patients undergoing VT ablation, we collected 31 parameters including medical history, echocardiography, and procedural data. 17 relevant features were included in the ML-based feature selection, which yielded six and five optimal features for 1-month and 1-year recurrence, respectively. We trained several supervised machine learning models using 10-fold cross-validation for each endpoint.

RESULTS

We observed 1-month VT recurrence was observed in 60 (18%) cases and accurately predicted using our model with an area under the receiver operating curve (AUC) of 0.73. Input features used were hemodynamic instability, incessant VT, ICD shock, left ventricular ejection fraction, TAPSE, and non-inducibility of the clinical VT at the end of the procedure. A separate model was trained for 1-year VT recurrence (observed in 117 (35%) cases) with a mean AUC of 0.71. Selected features were hemodynamic instability, the number of inducible VT morphologies, left ventricular systolic diameter, mitral regurgitation, and ICD shock. For both endpoints, a random forest model displayed the highest performance.

CONCLUSIONS

Our ML models effectively predict VT recurrence post-ablation, aiding in identifying high-risk patients and tailoring follow-up strategies.

Outcomes of Ventricular Tachycardia Catheter Ablation in Patients Who Underwent Cardiac Defibrillator Implantation Nationwide Readmission Database Analysis

The timing of when to perform ventricular tachycardia (VT) ablation while receiving an implantable cardioverter defibrillator (ICD) during the same hospitalization has not been explored. This study aimed to investigate the use and outcomes of VT catheter ablation in patients with sustained VT receiving ICD in the same hospital stay. The Nationwide Readmission Database 2016 to 2019 was queried for all hospitalizations with a primary diagnosis of VT with subsequent ICD during the same admission. Hospitalizations were later stratified according to whether a VT ablation was performed. All catheter ablation of VT were performed before ICD implantation. The outcomes of interest were in-hospital mortality and 90-day readmission. A total of 29,385 VT hospitalizations were included. VT ablation was performed with subsequent ICD placement in 2,255 (7.6%), whereas 27,130 (92.3%) received an ICD only. No differences were found regarding in-hospital mortality (adjusted odds ratio [aOR] 0.83, 95% confidence interval [CI] 0.35 to 1.9, p = 0.67) and all-cause 90-day readmission rate (aOR 1.1, 95% CI 0.95 to 1.3, p = 0.16). An increase in readmission because of recurrent VT was noted in the VT ablation group (aOR 1.53, 8% vs 5% CI 1.2 to 1.9, p <0.01); the VT ablation group encompassed a higher number of patients with heart failure with reduced ejection fraction (p <0.01), cardiogenic shock (p <0.01), and mechanical circulatory support use (p <0.01). In conclusion, the use of VT ablation in patients admitted with sustained VT is low and reserved for higher risk patients with significant co-morbidities. Despite the higher risk profile of VT ablation cohort, no differences were found in the short-term mortality and readmission rate between the groups.