Interatrial block and P terminal force in the general population – Longitudinal changes, risk factors and prognosis

BACKGROUND: Partial and advanced interatrial block (IAB) and P terminal force (PTF) in lead V1 are markers of atrial remodeling and risk factors for atrial fibrillation (AF). There is a lack of information about constancy and possible factors influencing the development of these P-wave abnormalities. METHODS: The study sample consisted of 6058 Finnish participants (mean age 52.16 ± 14.60 years, 45.0% male) from the general population with an ECG taken in a health examination, and from 3224 of these participants, who had a re-examination 11 years later. Risk factors for incident partial and advanced IAB and PTF were studied using binomial logistic regression analysis, and the prognostic significance of these ECG changes for new AF was studied using time-varying Cox regression analysis. RESULTS: The rate of reversal to normal of the studied ECG parameters were 47.4% for partial IAB, 40.0% for advanced IAB and 79.3% for PTF. Age, male sex, hypertension, higher BMI, higher LDL cholesterol, ECG left ventricular hypertrophy, use of beta blocker, and use of angiotensin-converting enzyme inhibitor or angiotensin II receptor antagonist were independently associated with a risk to develop incident P-wave abnormality. Partial IAB was independently associated with increased AF risk (HR 1.28 [95% CI 1.04-1.58]), as was also advanced IAB (HR 1.72 [95% CI 1.07-2.75]). CONCLUSION: Traditional cardiovascular risk factors increase the risk of a new P-wave abnormality. Partial and advanced IAB are associated with increased AF risk. Surprisingly, P-wave abnormalities are often reversible during long-term follow-up in the general population.