[The P wave in systemic arterial hypertension. Comparison with the echocardiogram and apexcardiogram]

The cause of an abnormal electrocardiographic P wave (AEPW) in systemic arterial hypertension (SAH) has not been delucidated. In order to demonstrate if this sign is related to volume overload of the left atrial cavity -previously we found no correlation between pressure overload of the cavity and the presence of an AEPW- 34 patients with SAH were studied; population were divided in two groups: group A (GA, n = 13), formed by 13 cases with a P wave more than 0.10 s duration (D2 standard lead) and group B integrated by 21 cases with a P wave at 0.10 s or less duration. In each cases phonocardiographic and echocardiographic (Mode M) studies were performed and the following data were obtained: "A" index (AI), left atrial dimension (LAD) and, septal (SD) and left posterior wall dimension (LPWD); besides: Sokolow electrocardiographic index (SI) and systolic (SBP) and diastolic (DBP) blood pressure. Results are shown in the following table: (Table: see text). There were not statistical differences between groups (data of SBP and DBP not shown). Correlation between LAD and AI and duration of P wave were not statistical different (data not shown). An AEPW in SAH does not seem to be cause by a volume left atrial overload. Possible it is related to an interatrial conduction defect.