Interventricular septal configurations and motions in patients with hypertrophic cardiomyopathy by angled biventriculography

: Precise configurations and motions of the interventricular septum (IVS) in hypertrophied hearts were assessed using angled biventriculography (BVG) for eight patients with apical hypertrophic cardiomyopathy (AH), three with hypertrophic obstructive cardiomyopathy (HOCM), six with hypertrophic non-obstructive cardiomyopathy (HNCM) and four with hypertensive heart disease (HHD). Analysis was by the computer system, OSCON. The configurations of the IVS differed among the four groups: the thickness of the IVS increased gradually towards the apex in patients with AH; that of the upper IVS increased abnormally in patients with HOCM; that of the mid-IVS increased in patients with HNCM; and that of the IVS increased uniformly in patients with HHD. The segmental thickening of the IVS also differed in each of the four groups. Among them, a characteristic pattern of the segmental thickening of the IVS was evident in patients with HNCM. In addition, the relative contributions of the IVS to right and left ventricular contractions in patients with AH and HHD differed from those in patients with HOCM and HNCM. Briefly, IVS contractions contributed more to the left than to the right ventricle in patients with AH and HHD, but not in those with HOCM and HNCM. Although further study is necessary, it can be concluded that AH can be regarded as one type of hypertrophic cardiomyopathy, according to its IVS configuration and motion.