[Prospective study of the diagnostic and prognostic criteria of right ventricular involvement in the acute phase of inferoposterior infarction].

Right ventricular involvement has been shown to be common in the acute phase of infero-posterior myocardial infarction. The aim of this prospective study was to assess the diagnostic and prognostic value of the different criteria obtained by clinical and paraclinical methods of investigation. Forty patients (35 men, 5 women: mean age 57,1 years) admitted consecutively with this type of transmural infarct without any other cause of acute or chronic volumic or barometric overload of the RV were investigated. In addition to clinical data, the following paraclinical investigations were carried out during the first three days of admission: ECG and vectorcardiogramme (VCG); transaminase levels (SGOT and SGPT), creatinine phosphokinase (CPK), alpha HBDH, serum creatinine, blood gases (pO2), M mode and 2 D echo, right heart catheterisation and cardiac output estimations, selective RV and pulmonary cineangiography centered on the LV in the monoplane 30 degrees LAO projection. Two groups of twenty patients were identified, comparable in age and sex, according to the angiographic extension of akinesia of the RV inferior wall: Group A: extensive akinesia (greater than or equal to 30 p. 100), Group B: very localised or no akinesia (less than 30 p. 100). Analysis of the results showed a number of features characterising patients in Group A: the high incidence of initial shock (45 p. 100 (A)/0 p. 100 (B] and signs of RV failure (85 p. 100/0 p. 100), higher SGOT, SEPT (p less than 0,05) and alpha HBDH (p less than 0,02) but not of CPK; much higher serum creatinine (p less than 0,01) and lower p02 (p less than 0,05); the ECG showed a high incidence (85 p. 100) and specificity (95 p. 100) of ST-T elevation in V3R and V4R, and also 2nd or 3rd degree AV block (60 p. 100/5 p. 100): there were no characteristic VCG changes. Catheterisation showed very significant increases (p less than 0,001) of mean RA, and RV end diastolic pressures, of the RA/mean pulmonary capillary pressure ratio and of Yu's index. There was a moderate increase in PCP (p less than 0,01), a drop in right ventricular systolic work index (RSSWI); adiastole was very common (90 p. 100) and very specific (95 p. 100); angiography showed an increase in RV end diastolic and end systolic volumes (p less than 0,05) and a fall in RV ejection fraction (p less than 0,05) but with a lot of individual variations; there were no significant differences between the two groups as regards the volumes, ejection fractions and p. 100 akinesia of the LV.(ABSTRACT TRUNCATED AT 400 WORDS)