The study
A population based cohort study of a subset of the US Cardiovascular Health Study performed 24-hour ECGs on 1139 patients aged 65 with normal left ventricular ejection fractions and no history of heart failure. Left ventricular ejection fraction was measured using echocardiograms at the start of the study and at five-year intervals. Median follow-up was over 13 years.
The findings
1 Patients whose frequency of ventricular ectopics was in the top quartile, compared to those in the bottom quartile, were found to have the following:
-three times higher risk of decrease in left ventricular ejection fraction over five years
-48% higher risk of congestive heart failure
-31% higher risk of death
2 The increased mortality was found to exist both before and after multivariate adjustment, and seemed to be partly attributable to CHF
3 Similar results were found when ventricular ectopics were assessed as a continuous variable
4 If ventricular ectopics >0.7% of total ventricular beats is used as a ‘test’ to assess risk of developing CHF over 15 years, the specificity of this test is >90%. The specificity increases to 99% for ectopics >10% of total ventricular beats
What this means for GPs
GPs should be aware ventricular ectopics are a useful predictor for heart failure and mortality
Ventricular ectopics are often viewed as a finding that requires no intervention. But in view of these findings, it could well be argued that patients with frequent ventricular ectopics should be monitored closely for heart failure, and that GPs should have a low threshold for investigation and intervention.
The paper
JACC (Journal of the American College of Cardiology) July 2015
Dr Hamed Khan is a GP in the emergency department of St George’s, London, and a clinical lecturer. He tweets as @drhamedkhan
