[Effects of intravenous trinitrine on myocardial function in left ventricular insufficiency]

The effects of intravenous trinitrin on myocardial function have been studied in 40 patients with heart failure (26 cases of coronary artery disease and 14 of apparently primary cardiomyopathy). Each patient had measurements made of left ventricular pressure, of cardiac output by the dye dilution method, of volume, of the left ventricular ejection fraction, and of the segmental parietal kinetics by means of left side ventriculography both before and after trinitrin. The following results were obtained after injection of trinitrin:--no change in rhythm and cardiac index;--an almost constant decrease in left ventricular end diastolic pressure (38 cases out of 40);--a decrease in arterial pressure and ventricular volume in about two thirds of cases;--improvement of the ejection fraction (25 cases out of 40), and of segmental parietal kinetics (26 cases out of 40) in the left ventricle. These findings were equally true in the patients with coronary artery disease and in the cardiomyopathies. In the light of these results, it appears that when used in left ventricular failure, trinitrin almost always decreases the load, but improves ventricular kinetics only in two thirds of cases, while it has no influence on cardiac output. In addition, given the difficulties in establishing a standard dose of trinitrin, the authors discuss the methods of establishing the optimal dose.