The Relationship between Frequent and Complex Ventricular Ectopy during 24 h Ambulatory Electrocardiographic Monitoring

Abstract

Complex and frequent ventricular ectopy have been associated with an increased risk of sudden death in certain patient groups. To evaluate the relationship between complexity and frequency of ventricular ectopy, 275 consecutive 20- to 24-hour ambulatory electrocardiograms were analyzed. The unselected study population included 56% males and the average age was 56. Prior myocardial infarction was present in 28%. Dizziness, palpitations and syncope were present in 16, 30 and 13%, respectively. Complex ventricular ectopy (complexity) was defined as multiformity, bigeminy, couplets or salvos, ventricular tachycardia (VT), and R on T. Premature ventricular depolarizations (PVDs) were observed in 230 of 275 records and exhibited one or more criteria for complexity in 164 (71 %). Of the 164 records with complexity, 71 % had multiformity, 35% bigeminy, 32% couplets, 5% VT, and 22% R on T. Of 159 records with average PVD frequency ≤30/h, 98 (61%) exhibited complexity, whereas 66 of 71 (93%) records with > 30 PVD/h had complexity. Of 113 records with > 100 PVDs/24 h, 102 (90%) exhibited complexity, whereas 60 of 99 (61 %) records with between 2 and 100 PVDs on the entire record showed complexity. Of the 164 records with complexity, 43 had ‘rare PVDs’ ( < 30/24 h), but exhibited 72% multiformity, 5% bigeminy, 25% couplets, 2% VT, and 14% R on T. This study demonstrates a high prevalence (50–60%) of complexity in patients with ‘infrequent’ PVDs defined as < 30/24 h, < 30