[Importance of the ECG for evaluation of severity of pulmonary embolisms].

I Horák, K Dvorák: II. interní oddĕlení-kardiovaskulární, Mĕstská nemocnice Ostrava.

OBJECTIVE: To evaluate whether it is possible on the basis of ECG examination to judge the haemodynamic impact of pulmonary embolism.

METHOD: To compare by retrospective analysis of hospital documentation of patients at the medical department the assessed ECG changes with the echocardiographic finding of pulmonary hypertension and right ventricular dilatation. As positive an ECG finding was evaluated involving changes of the ST-T segment in VI-V4, S1Q3T3 negative or right bundle branch block (RBBB). As a positive echocardiographic finding the authors evaluated the size of the right ventricle above 30 mm or the shape of the acceleration curve in the outflow tract of the right ventricle corresponding to pulmonary hypertension.

RESULTS: The authors analyzed 179 patients with clinically diagnosed pulmonary embolism during the period from Jan. 1 1996 till Dec. 31 2000. A positive ECG finding was recorded in 103 patients, i.e. 57.5%. Echocardiographic examination was made in 112 and 65 of them had a positive ECG. An echocardiographic finding of pulmonary hypertension or dilatation of the right ventricle was recorded in 92 patients. In case of positivity of at least one ECG finding an ECG sensitivity of 62% and specificity of 60% was found. In case of changes in the ST-T segment in V1-V4 the sensitivity and specificity was 47% and 70% resp., for S1Q3T3 negative 27% and 80% resp. and PRT block 25% and 90% resp.

CONCLUSIONS: The absence of ECG changes does not rule out serious pulmonary embolism. The finding of typical ECG changes is very frequently associated with pulmonary hypertension, right ventricular dilatation and a serious haemodynamic finding.