Fast rate （≥ 250 beats/min） right ventricular burst stimulation is useful for ventricular tachycardia induction in arrhythmogenic right ventricular cardiomyopathy

Background One of the major challenges in arrhythmogenic right ventricular cardiomyopathy （ARVC） ablation is ventricular tachy-cardia （VT） non-inducibility. The study aimed to assess whether fast rate （≥ 250 beats/min） right ventricular burst stimulation was useful for VT induction in patients with ARVC.Methods Ninety-one consecutive ARVC patients with clinical sustained VT that underwent electro-physiological study were enrolled. The stimulation protocol was implemented at both right ventricular apex and outflow tract as follows： Step A, up to double extra-stimuli; Step B, incremental stimulation with low rate （＆lt; 250 beats/min）; Step C, burst stimulation with fast rate （≥ 250 beats/min）; Step D, repeated all steps above with intravenous infusion of isoproterenol.Results A total of 76 patients had inducible VT （83.5%）, among which 49 were induced by Step C, 15 were induced by Step B, 8 and 4 by Step A and D, respectively. Clinical VTs were induced in 60 patients （65.9%）. Only two spontaneously ceased ventricular fibrillations were induced by Step C. Multivariate analysis showed that a narrower baseline QRS duration under sinus rhythm was independently associated with VT non-inducibility （OR： 1.1; 95% CI： 1.0-1.1;P = 0.019）.ConclusionFast rate （≥ 250 beats/min） right ventricular burst stimulation provides a useful supplemental method for VT induction in ARVC patients.