Clinical significance of ventricular gradient with a right orientation.

In 1,000 patients on whom vectorcardiography was performed, ventricular gradients (G) were calculated using a micro-computer. In 73 patients, excluding those with dextrocardia and atrial fibrillation, the X component of the ventricular gradient (Gx) showed a negative value. These patients with a negative Gx were divided into the following 10 subgroups and their G were compared: hypertrophic non-obstructive cardiomyopathy (HCM), hypertrophic obstructive cardiomyopathy (HOCM), congestive cardiomyopathy, concentric left ventricular hypertrophy, aortic valvular disease, ischemic heart disease, myocardial infarction, pericarditis, right ventricular hypertrophy and others. The HCM group was the most characteristic with large Aqrs oriented to the left, the largest At oriented to the right and the largest G oriented to the right. Gx in this group showed values more negative than -50 micro V . sec (-92.2 +/- 32.0) and significantly differed from other groups.