[Correlation between the angiographic appearance and the left intraventricular gradient in obstructive...

42 patients who were given the diagnosis of obstructive cardiomyopathy (OCM) on the basis of a basal left intraventricular systolic gradient equal to or in excess of 20 mmHg were divided into two groups, according to the angiocardiographic appearances (in the right anterior oblique projection) of the left ventricular cavity during systole. In 20 cases the appearances were those of a typical obstructive cardiomyopathy. In the other 22, despite the presence of a fairly large left intraventricular gradient, the appearances on angiocardiography were closest to those described for the non-obstructive cardiomyopathies with diffuse myocardial hypertrophy. These two groups were compared in the quest for a difference between the clinical, radiological, electrocardiographic, phonomechanographic, and haemodynamic picture on the one hand, and the appearances at angiography on the other. These two groups can only be separated by the mean value of the left intraventricular systolic gradient established under basal conditions; this is greater when the angiographic picture is less characteristic. However, the value of this gradient is shown by the positive correlation between the figure for the gradient and that for the left ventricular ejection time, as determined from external phonomecanographic measurements and from the catheter on the left side. This determination confirms the existance of obstruction to the outflow and the diagnosis of obstructive cardiomyopathy, even when the angiographic appearances are not typical.