Significance of the clinical presentation in ventricular tachycardia/fibrillation

We examined the hypothesis that clinical presentation in patients with sustained ventricular tachycardia/fibrillation (VT/VF) predicts clinical, electrophysiologic (EP) findings and long-term outcome. We included in the study 121 consecutive patients seen in our EP laboratory with documented and inducible sustained VT/VF. Patients were categorized into three groups according to their clinical presentation: (1) cardiac arrest (CA)-53 patients; (2) syncope (S)-20 patients; (3) palpitations/dizziness (P)-48 patients. There were no significant differences in age, sex, or prevalence of underlying heart disease between groups. The left ventricular ejection fraction (LVEF) was significantly lower for patients with CA (mean ± S.D.; 31 ± 14%) or S (20 ± 11%) when compared with P (39 ± 15%) (p <0.05). Induction of VT/VF required a more aggressive stimulation protocol (three extrastimuli) in patients with CA (53%) when compared with patients with S (30%) or P (29%) (p <0.05). The cycle length of the induced VT was shorter for CA (239 ± 64 msec) patients as compared with the S (294 ± 67 msec) or the P (319 ± 94 msec) patients (p <0.01). Polymorphic VT or VF was induced in 28% of CA patients, in 9% of S patients, and in 12% of P patients (p <0.05). There were significantly more sudden deaths observed during the 4-year follow-up interval in patients presenting with CA compared to the P group (p <0.05). The 4-year survival was 67 ± 8% for P, 45 ± 15% for S, and 45 ± 10% for CA patients (N.S.). In conclusion, patients presenting with P have less compromised left ventricular function, slower rates of inducible VT, and a decreased incidence of subsequent sudden death when compared with patients presenting with CA.