Significance of Electrocardiographic Isolated Abnormal Terminal P-Wave Force (Left Atrial Abnormality)

Abstract

• An abnormal terminal negative deflection in precordial lead V₁(PTFV₁) is occasionally present as an isolated electrocardiographic finding. To determine the significance of this, 41 patients with PTFV₁greater than or equal to 0.04 mms were recalled for a repeated electrocardiogram as well as an echocardiographic examination. Patients were classified as cardiovascular normal (n=15) or abnormal (n=26). Left atrial enlargement was the most common echocardiographic abnormality found, but represented less than a third of the total. P-wave prolongation (&gt;110 ms) was present in 30 of the 41 patients and 21 of the 26 abnormal patients. This persisted into the second study, while the PTFV₁fell significantly in both the normal and abnormal groups. Among the P-wave abnormalities found, combinations were used to identify patients most likely to have cardiovascular disease. The most discriminating was an initial abnormal PTFV₁in combination with P-wave prolongation (sensitivity, 82%; specificity, 40%; positive predictive value, 70%; and negative predictive value, 55%). Maximal specificity (93%) and positive predictive value (88%) were achieved when P-wave prolongation and PTFV₁greater than or equal to 0.06 mms were present in both studies, although the sensitivity for this criterion was only 27%. The isolated P-wave abnormality described may be helpful in suggesting the presence of underlying cardiovascular disease and indicate the need for further evaluation. (<i>Arch Intern Med</i>1988;148:1545-1549)