Effect of ethnicity and hypertension on atrial conduction: Evaluation with high‐resolution p‐wave signal averaging

Background: Measurements by P‐wave signal‐averaged electrocardiogram (P‐SAECG) of P‐wave duration and P‐wave voltage integral are higher in patients with atrial fibrillation (AF) than in those with sinus rhythm. Hypertension is perhaps the most common cardiovascular antecedent cause of AF, and particularly a disproportionate cause of morbidity and mortality among blacks. The purpose of this study was to examine the effect of hypertension and ethnicity on P‐SAECG parameters in patients without AF. Hypothesis: It was hypothesized that P‐SAECG parameters can identify hypertensives, and are disproportionately higher in hypertensive blacks. Methods: in all, 234 normotensives and 84 hypertensives underwent P‐SAECG analysis. in an ancillary study group of 34 hypertensive black men, the relationship between severity of hypertension and measured parameters of P‐SAECG was evaluated. Results: Mean filtered P‐wave duration and total P‐wave voltage integral for normotensives of both ethnic groups were similar. Hypertensive blacks had greater increase in P‐wave duration (138 ± 16 vs. 132 ± 12 ms; p< 0.01, N 42:42) and total P‐wave voltage integral (922 ± 285 vs. 764 ± 198 μV‐ms; p < 0.001) than white hypertensives. Filtered P‐wave duration and total P‐wave voltage integral increased with severity of hypertension. Conclusions: Patients at very early stages of hypertension have demonstrable evidence of prolonged atrial conduction by P‐SAECG and, thus, cardiac electrical remodeling. P‐wave duration and total P‐wave voltage integral increase with severity of hypertension. Hypertensive blacks manifest a greater increase in P‐SAECG parameters than whites. This may portend an increased cardiovascular risk for black patients with hypertension.