Background and ObjectivesFrequent ventricular premature complex (VPC) is one of the most common arrhythmia syndromes. Symptoms observed frequently with this arrhythmia syndrome remain limited. We sought to identify predictors of VPC-related symptoms by analyzing demographic information, VPC burden, and VPC surface electrocardiogram characteristics.Subjects and MethodsWe prospectively enrolled 109 patients with idiopathic outflow tract VPCs (63 males, 49±16 years old). They were divided into Group A (n=30, without VPC-related symptoms of palpitations or "dropped beats") and Group B (n=79, with VPC-related symptoms). Measured parameters were sinus and VPC QRS width, coupling interval (CI) between the previous sinus beat and VPC, CI ratio (%, CI/sinus cycle length), post-VPC CI and CI ratio, and VPC amplitude.ResultsBoth groups had similar age (p=0.22), daily VPC burden (p=0.15), and VPC site of origin (p=0.36). The VPC CI ratio was higher in Group B (60±15%) than in Group A (49±22%) (p=0.01).ConclusionVPC-related symptoms are associated with a higher VPC CI ratio (>50%). The physiologic basis for these results deserves further study.