P waves in acute myocardial infarction.

Relationships between P wave abnormalities in lead II and V1 and clinical as well as hemodynamic findings and the prognosis of 27 attacks of AMI were evaluated. 1) Patients with clinical left ventricular failure showed large negative deflections in lead V1 compared to patients without. 2) There was a significant correlation between the magnitude of PTF-V1 and PCW (r=-0.75, p less than 0.01). 3) In 20 of the 27 attacks (74%), PTF-V1 correctly identified whether or not PCW was normal on admission. 4) Patients with frequent premature beats and any of the bundle branch blocks had a large negative deflection in V1 compared to patients without. 5) There was a significant correlation between the magnitude of PTF-V1 and Peel's prognostic index (r=-0.74, p less than 0.01). Moreover, 70% of the patients with abnormal PTF-V1 (less than -0.03 mm-sec) and elevated Peel's prognostic index (more than 12) died during hospitalization. 6) The patients who died during hospitalization had a large negative deflection in lead V1 compared to those patients who survived. 7) Patients with past history of old myocardial infarction had a larger negative deflection in lead V1 compared to the patients without past history of old myocardial infarction. 8) There is no correlation between the duration and amplitude of P wave in lead II and PCW. 9) Thus, it is concluded that in patients with AMI, the magnitude of PTF-V1 reflects the level of PCW and is useful as a parameter for therapy and prognosis evaluation.