Evaluation of Left Coronary Vascular Bed Reserve in Patients with Hypertensive Cardiac Hypertrophy

Abstract

This study was designed to evaluate left coronary vascular bed reserve in hypertensive cardiac hypertrophy. The subjects were eight patients with hypertensive cardiac hypertrophy (HT) and nine patients with normal coronary flow (N). Coronary sinus flow (CSF) was measured by a continuous thermodilution method, and the ascorbic acid-platinum reaction was employed for the mean transit time measurement (T0-T2) of left coronary flow. T0 is ascorbic acid injection into the left coronary orifice and T2 is the maximal point of detecting ascorbic acid volume in the coronary sinus. Volumes for the coronary vascular bed (CVB) were obtained by multiplying CSF and T0-T2. CVB value in the HT patients was more than that in the control group at control heart rate, but was less than in N at a high pacing rate. CSF in the HT patients was more than that in the N group at any heart rate, and the CVB values per unit of myocardial mass were less in the HT patients than in the N group. The pressure rate product in the HT patients was more than that in the normal coronary flow group. The transit time of left coronary flow in the HT patients was less than that in the N group. The CVB in the HT group was more than that in the normal coronary group at control heart rate and less than that in the normal group at a high pacing rate. Cardiac work in the HT patient was thus shown to be greater than that in the normal group.