Epicardial catheter ablation is an established treatment for ventricular tachycardia (VT) in patients with structural heart disease (SHD); however, VT recurrence remains frequent, particularly in advanced cardiomyopathy. To identify clinical and electrophysiological determinants of VT recurrence following epicardial VT ablation in SHD. Seventy-four patients with SHD undergoing epicardial VT ablation were included. Acute procedural outcomes, VT recurrence, and adverse clinical events were assessed. Nonischaemic cardiomyopathy was the predominant etiology. Epicardial scar predominantly involved basal-lateral left ventricular regions with periannular and outflow tract extension. Acute procedural non-inducibility was achieved in 49 patients (66%), while VT recurrence occurred in 37 patients (50%) during follow-up of 17 months. In cause-specific Cox analysis, electrical storm (HR 3.130, 95% CI 1.421-6.893; p=0.005), longer VT cycle length (HR 2.835, 95% CI 1.211-6.638; p=0.016) and higher body mass index (BMI, HR 2.918, 95% CI 1.365-6.236; p=0.006) were independently associated with VT recurrence. During follow-up, 7 patients died, 10 underwent heart transplantation, and 2 required ventricular assist device implantation. Combined endocardial and epicardial VT ablation in advanced SHD was associated with moderate acute success, while VT recurrence remained common during follow-up. Electrical storm, longer VT cycle length, and higher BMI were independently associated with an increased risk of recurrence.