[Non-obstructive hypertrophic myocardiopathy. Apropos of 5 cases]

Out of a total of 1 470 cardiac catheterisations performed in one year, 5 were motivated by the chance finding of giant negative T waves, greater than 10 mm and maximal in leads V3, V4. The patients were all males with an average age of 50 +/- 3,2 years. Four were asymptomatic and the other had scleroderma. The changes partially regressed on exercise electrocardiography. M mode echocardiography showed normal septal (8,8 +/- 0,25 mm) and posterior wall (8,38 +/- 0,21 mm) thickness and a normal septum/posterior wall ratio (1,02 +/- 0,01). Coronary angiography was normal in all cases. Left ventricular and diastolic pressure was raised after ventriculography (21 +/- 1,34 mm Hg). There was no intraventricular pressure gradient. Left ventriculography in the 30 degrees right anterior oblique plane showed an end diastolic appearance similar to that of the ace of spades and the apex was obliterated in systole. End diastolic volumes (68 +/- 4,7 ml/m2) and ejection fractions (68,6 +/- 5,21) were normal. The wall thickness measured from the angiography was 10,4 +/- 0,81 mm at the mid zone of the anterior wall and 17,2 +/- 0,85 at the apex with a septum / posterior wall ratio of 1,67 +/- 0,08. In three cases, atrial pacing with coronary arterial and venous lactate sampling revealed abnormalities in myocardial metabolism. The final diagnosis was of non obstructive apical hypertrophic cardiomyopathy. The site of hypertrophy explains the electrical changes. The prognosis of this cardiomyopathy is still unknown, one regression and two aggravations of the electrical changes have been observed. continuous 24 hour ECG showed an episode of ventricular tachycardia in 1 patient, which would imply a reserved prognosis.