P‐Wave Morphologic Characteristics Predict Cardiovascular Events in a Community‐Dwelling Population

BACKGROUND: There have been few reports on the relationship between P-wave characteristics and long-term cardiovascular events. METHODS: A nested case-control study was conducted as part of the Jichi Medical School cohort study, which enrolled 12,490 subjects in a community-dwelling population. The mean follow-up period was 10.7 years. The P-wave characteristics of 526 patients who suffered cardiovascular events (fatal/nonfatal stroke, fatal/nonfatal myocardial infarction, and sudden death) within the follow-up period (case group) were compared with those of 1578 matched controls (control group). The P-wave morphology was classified as normal, deflected, and notched type in precordial leads. A broad P wave was defined as a maximum P-wave duration of more than 120 ms in any of the 12 leads. RESULTS: The mean age was 64 ± 8 years and the percentage of males was 54% in both groups. A notched P wave at baseline was observed in 10.1% of the case group and 6.0% of the control group (P = 0.001). A notched P wave was a significant predictor of cardiovascular events after adjustment for covariates (odds ratio = 1.59; 95% confidence interval = 1.08-2.33). Among the patients with left ventricular hypertrophy as evaluated by the Sokolow-Lyon criteria or Cornell product criteria, there was no significant difference in cardiovascular events between those with and those without a notched P wave, but in the absence of left ventricular hypertrophy, patients with a notched P wave suffered more cardiovascular events than those without a notched P wave by each criteria. CONCLUSION: P-wave morphologic characteristics were effective for predicting cardiovascular events.