Predictors of adverse outcome in patients with frequent premature ventricular complexes: The ABC-VT risk score

Background No independently validated score currently exists for risk stratification of patients with frequent premature ventricular complexes (PVCs). Objectives The purpose of this study was to develop a risk score to predict adverse events in patients with frequent PVCs. Methods We analyzed consecutive patients between 2012 and 2017 undergoing 14-day continuous monitoring with frequent PVCs (>5%) and concurrent echocardiography. We performed binary logistic regression to determine multivariate predictors of adverse left ventricular remodeling (left ventricular ejection fraction [LVEF] <45% or left ventricular end-diastolic volume index >75 mL/m2). A risk score was created using the log(odds ratio (OR)) of these predictors and validated prospectively to determine the risk of future adverse events in those with baseline LVEF >45%. An adverse event was defined as LVEF decline by 10%, heart failure hospitalization, or cardiovascular mortality. Two validation cohorts were used: follow-up from the original derivation cohort (cohort 1) and an independent Korean PVC registry (cohort 2). Results The derivation cohort comprised 206 patients with a mean PVC burden of 11.6% ± 6.2% and considerable daily fluctuation (minimum burden 7.3% ± 6.2% vs maximum 17.9% ± 8.0%). Independent predictors of adverse remodeling were as follows: superiorly directed PVC axis (OR 2.7; 1 point), PVC burden 10%–20% (OR 3.5; 2 points) and >20% (OR 4.4; 3 points), PVC coupling interval >500 ms (OR 4.7; 4 points), nonsustained ventricular tachycardia (OR 5.3; 4 points), which form the ABC-VT risk score. This score predicted future adverse events in both validation cohorts: cohort 1, hazard ratio 1.43; 95% confidence interval 1.19–1.73; P < .001 and cohort 2, hazard ratio 1.22; 95% confidence interval 1.05–1.42; P = .01. Conclusion The ABC-VT score is a simple tool that predicts adverse left ventricular remodeling and future clinical deterioration in patients with frequent PVCs. No independently validated score currently exists for risk stratification of patients with frequent premature ventricular complexes (PVCs). The purpose of this study was to develop a risk score to predict adverse events in patients with frequent PVCs. We analyzed consecutive patients between 2012 and 2017 undergoing 14-day continuous monitoring with frequent PVCs (>5%) and concurrent echocardiography. We performed binary logistic regression to determine multivariate predictors of adverse left ventricular remodeling (left ventricular ejection fraction [LVEF] <45% or left ventricular end-diastolic volume index >75 mL/m2). A risk score was created using the log(odds ratio (OR)) of these predictors and validated prospectively to determine the risk of future adverse events in those with baseline LVEF >45%. An adverse event was defined as LVEF decline by 10%, heart failure hospitalization, or cardiovascular mortality. Two validation cohorts were used: follow-up from the original derivation cohort (cohort 1) and an independent Korean PVC registry (cohort 2). The derivation cohort comprised 206 patients with a mean PVC burden of 11.6% ± 6.2% and considerable daily fluctuation (minimum burden 7.3% ± 6.2% vs maximum 17.9% ± 8.0%). Independent predictors of adverse remodeling were as follows: superiorly directed PVC axis (OR 2.7; 1 point), PVC burden 10%–20% (OR 3.5; 2 points) and >20% (OR 4.4; 3 points), PVC coupling interval >500 ms (OR 4.7; 4 points), nonsustained ventricular tachycardia (OR 5.3; 4 points), which form the ABC-VT risk score. This score predicted future adverse events in both validation cohorts: cohort 1, hazard ratio 1.43; 95% confidence interval 1.19–1.73; P < .001 and cohort 2, hazard ratio 1.22; 95% confidence interval 1.05–1.42; P = .01. The ABC-VT score is a simple tool that predicts adverse left ventricular remodeling and future clinical deterioration in patients with frequent PVCs.