Practice Update: Cardiology

ARRHYTHMIAS/HEART RHYTHM DISORDERS 24

PAC or PVC on 12-Lead ECG May Predict Risk of Atrial Fibrillation, Heart Failure, or Death Journal of the American Heart Association Take-home message • The authors of this retrospective study aimed to determine if premature atrial contractions or premature ventricular contractions on a 12-lead ECG predicted long-term cardiovascular outcomes and death. They used data from the Cardi- ovascular Health Study (CHS), which included 5577 participants observed for a median of 12 years. A baseline 12-lead ECG with premature atrial contraction was associated with an increased risk of atrial fibrillation (HR, 1.6; P < .001) and death (HR, 1.3; P = .008). Likewise, premature ventricular contraction on the baseline 12-lead ECG was associated with an increased risk of heart failure (HR, 1.3; P = .021) and death (HR, 1.2; P = .044). • This study demonstrated that premature atrial contraction and premature ventricular contractions on 12-lead ECG are predictive of long-term cardiac complications and death. Abstract

COMMENT By Samuel J Asirvatham MD, FACC, FHRS and Danesh Kella MBBS

You Can’t Have Two Without Ever Having One… Introduction

The 12-lead electrocardiogram, although a commonly performed test, is a momen- tary snapshot attempting to capture a high frame rate video sequence repre- senting heart health over an extended period of time. In this context, the unique findings first reported by Nguyen et al are eye-catching and of potentially significant clinical and population-wide relevance. The authors report that, from a single 12-lead electrocardiogram, one pre- mature atrial contraction (PAC) predicts incident atrial fibrillation (AF) and death, and one premature ventricular contrac- tion (PVC) predicts incident heart failure and death. Utility and Impact Ascertainment bias is a major limita- tion of most attempts that correlate an unanticipated finding from a test with outcomes that are intimately linked with the indication for which a test is typically ordered. For example, just the fact that

BACKGROUND Atrial fibrillation and heart failure are 2 of the most common diseases, yet ready means to identify individuals at risk are lacking. The 12-lead ECG is one of the most accessible tests in medicine. Our objective was to deter- mine whether a premature atrial contraction observed on a standard 12-lead ECG would pre- dict atrial fibrillation and mortality and whether a premature ventricular contraction would predict heart failure and mortality. METHODS AND RESULTS We utilized the CHS (Car- diovascular Health) Study, which followed 5577 participants for a median of 12 years, as the pri- mary cohort. The ARIC (Atherosclerosis Risk in Communities Study), the replication cohort, captured data from 15 792 participants over a median of 22 years. In the CHS, multivaria- ble analyses revealed that a baseline 12-lead ECG premature atrial contraction predicted a 60% increased risk of atrial fibrillation (hazard ratio, 1.6; 95% CI, 1.3-2.0; P<0.001) and a pre- mature ventricular contraction predicted a 30% increased risk of heart failure (hazard ratio, 1.3; 95% CI, 1.0-1.6; P=0.021). In the negative control analyses, neither predicted incident myocardial infarction. A premature atrial contraction was associated with a 30% increased risk of death (hazard ratio, 1.3; 95% CI, 1.1-1.5; P=0.008) and a premature ventricular contraction was associ- ated with a 20% increased risk of death (hazard ratio, 1.2; 95% CI, 1.0-1.3; P=0.044). Similarly sta- tistically significant results for each analysis were also observed in ARIC. CONCLUSIONS Based on a single standard ECG, a premature atrial contraction predicted inci- dent atrial fibrillation and death and a premature ventricular contraction predicted incident heart failure and death, suggesting that this commonly used test may predict future disease.

Ectopy on a single 12-lead ECG, incident car- diac myopathy, and death in the community. J Am Heart Assoc 2017 Aug 03;6(8)e006028, KT Nguyen, E Vittinghoff, TA Dewland, et al. www.practiceupdate.com/c/56688

PRACTICEUPDATE CARDIOLOGY