Prognosis After Finding Incidental Ventricular Tachycardia on Ambulatory Electrocardiogram-recording

The prognostic significance of incidental non-sustained ventricular tachycardia (NSVT) in subjects without apparent heart disease is unknown. We aimed to evaluate short- and long-term prognosis of NSVT in the Copenhagen Holter Study cohort. From the study, 678 middle-aged and elderly subjects had minimum 48 hours of Holter-recording, laboratory testing and physician-based examination and questionnaire performed. Median follow-up time was 14.7 years. NSVT was defined as runs of minimum three premature ventricular complexes. The primary end-point was a combination of cardiovascular mortality, acute myocardial infarction, coronary revascularization or stroke. Secondary endpoints were all-cause mortality and components of the primary end-point. We found that 72 (10.6%) had minimum one NSVT event on 48-hour Holter-recording. The primary end-point occurred more frequently in patients with NSVT than those without: 38.3 versus 17.7 events per 1,000 patient-years, hazard ratio 2.1, 95% CI 1.37 to 3.20 after adjustment for risk factors. Secondary end-points also occurred more frequently in the NSVT-group. A shorter-term follow-up revealed similar event rates for the primary outcome; 47.5 versus 21.2 events per 1,000 patient-years, hazard ratio 1.9, 95% CI 0.69 to 5.24. Besides stroke other secondary end-points occurred more frequently in the short-term follow-up. The prognosis in subjects with NSVT was not dependent of the length of the VT. In conclusion, incidental asymptomatic NSVT on Holter-recording in subjects without apparent or manifest structural heart disease is associated with increased risk of mortality and cardiovascular events, however the increased risk is not imminent but with a slow and steady pace over time.