Prevalence and Prognostic Significance of Abnormal P Terminal Force in Lead V1 of the ECG in the General Population

Background— Prevalence and prognostic significance of abnormal P terminal force (PTF) in the general population are not known. The aim of this study was to assess the prevalence of abnormal PTF and to compare clinical outcomes of middle-aged subjects with and without the PTF. Methods and Results— The presence of PTF was assessed in a cohort of 10 647 middle-aged subjects (mean age [SD], 44 [8] years; 47.2% female). The subjects were followed 35 to 41 years, and data on mortality and hospitalizations were obtained from national registers. Primary outcomes were all-cause mortality, cardiac mortality, and arrhythmic death. Secondary outcomes were hospitalization because of congestive heart failure, coronary heart disease, new onset atrial fibrillation, and stroke. The Cox proportional hazards model was used to assess the risk for death (all-cause), and the Fine and Gray competing risks model was used for other outcomes. The prevalence of PTF 0.04 to 0.049, 0.05 to 0.059, and ≥0.06 mm·s were 4.8%, 1.5%, and 1.2%, respectively. Subjects presenting PTF ≥0.04 mm·s were at increased risk for death, cardiac death, and congestive heart failure, and subjects presenting PTF ≥0.06 mm·s were at increased risk for atrial fibrillation. However, after adjustment for potential confounding factors, an increased risk was observed only for death (hazard ratio, 1.76; 95% confidence interval, 1.45–2.12; P <0.001) and atrial fibrillation (hazard ratio, 1.91; 95% confidence interval, 1.34–2.73; P <0.001) in subjects presenting PTF ≥0.06 mm·s. Conclusions— PTF ≥0.04 mm·s is a relatively common finding in a 12-lead ECG of middle-aged subjects. PTF ≥0.06 mm·s is associated with increased risk for atrial fibrillation and death in the general population.