P-Wave Analysis in Valvular Heart Disease

Electrocardiographic analysis of the P waves occurring in a series of 113 normal subjects and 100 patients with specifically defined valvular lesions are reviewed. The former methods of analysis showed a marked lack of specificity. By dividing the P wave in lead V 1 into initial and terminal portions, a measure designated as the P terminal force has been derived. This measure is of value in two respects: (1) it correctly separates normal subjects from those patients with left-sided valvular lesions in 92 per cent of this series and (2) once a given valve lesion is suspected clinically, this measure enables one to make an estimation of the severity of that lesion from the degree of abnormality of the P terminal force at V 1 . The P terminal force does not indicate the type of valvular disease present, nor does it correlate with any one specific hemodynamic measure. The abnormality does appear to be related, within each separate type of valve disease, to the specific hemodynamic abnormality of that type of valvular involvement. The anatomic and electrophysiologic changes that might relate to these P-wave changes are discussed.