[Predictability of electrocardiographic and vectorcardiographic criteria in pulmonary arterial hypertension caused by chronic bronchopneumopathies]

The Authors have verified in a group of 38 patients with chronic obstructive pulmonary disease (COPD) and suspected pulmonary arterial hypertension (PAH) of precapillary origin the possibility to forsee the pressure within the lesser circulation starting from some electrocardiographic and vectorcardiograhic criteria. The vectorcardiographic analysis has not been shown to be more reliable than the traditional ECG as far as the identification of an eventual PAH is concerned. The matching of both scalar and vectorial criteria has significantly increased the efficiency of the estimate, i.e. the possibility to foresee the right ventricular systolic pressure (RVSP) and the mean pulmonary arterial pressure (PAP), but the same efficiency has remained at unsatisfactory level (S = +/- 10,30 Torr as far as the PAP is concerned. With regard to the value of the various scalar and vectorial criteria or parameters, among the electrocardiographic criteria the most reliable has been the inversion of the T wave in the right precordial leads. This sign, however, did not often appear in the present series (18% of the cases). As to the VCG the analysis made by the Authors stresses as the most reliable criterion the direction of QRS loop rotation on the horizontal plane and the magnitude of the maximum rightward spatial vector. These two elements, among other things, escape detection on the traditional electrocardiographic investigation. The above mentioned conclusions, obviously, only apply to the PAH secondary to COPD, in which particular noncardiac (lung hyperinflation, lowering of the diaphgram, etc.) and cardiac (associated left ventricular hypertrophy) factors contribute to limit the diagnostic value of both the ECG and the VCG.