Abstract 12140: Risk of Death as a Function of the PR-Interval: Results From the Duke Databank for Cardiovascular Disease
Objective: Recently, a U-shaped association between PR-interval and the risk of atrial fibrillation was described, with a higher risk observed both in patients with extremely long and short PR-intervals. The objective of the present study was to explore the relationship between PR-interval and mortality in patients with known coronary heart disease.
Methods: Patients in sinus rhythm, without acute coronary syndromes, undergoing coronary angiography at Duke University Medical Center from Jan 1989 to Dec 2010, who had at least 1 native coronary artery stenosis ≥75% were included. Patients with PR 120 ms were excluded. PR measurements were obtained from a baseline electrocardiogram.
Results: A total of 9,564 patients were included (median age 63 [55, 71] yrs, 67% men). Heart failure was present in 23%, 71% had a history hypertension and 33% had diabetes. PR-interval was longer in men compared with women (179±32 vs. 173±28 ms, P≤0.001) and increased with increasing age (169±25 ≤50 yrs vs. 185±36 ≥70 yrs, P≤0.001). The five-year event rate for all-cause mortality was 22.3% (Figure). After adjustment for relevant covariates, a non-linear relationship between PR interval and mortality was observed (P=0.003). The association with mortality was stronger for shorter PR-intervals, with 4.7% decrease in the likelihood of death per 10 ms increase in PR-interval below 165 ms (HR 0.953, 95% CI 0.919-0.988, P=0.0095). In contrast, a trend towards increased likelihood of death with increasing PR-intervals was seen in patients with PR ≥ 165 ms (HR 1.012, 95% CI 0.999-1.025, P=0.0630).
Conclusion: In patients with known coronary heart disease, PR-interval is independently associated with mortality. Increased risk appears to be associated with short as well as long PR-intervals. This, together with previous data, indicates that it may be appropriate to consider not only a prolonged PR-interval as a marker of increased risk, but also a short PR-interval.
- © 2013 by American Heart Association, Inc.