IMPROVEMENT OF CORONARY VASODILATATION CAPACITY THROUGH SINGLE LDL APHERESIS

A concomitant phenomenon of hypercholesterolemia is reduced coronary v asodilatation capacity due to disturbed endothelial function. Endothel ial function can be partially or completely normalized by reducing cho lesterol levels through drug therapy, but it is still unclear how rapi dly this desired effect is achieved. An interval oi between weeks and months has been presumed. LDL apheresis (LDL-A) is capable of achievin g a high-degree LDL cholesterol reduction within hours. With positron emission tomography (PET), carried out immediately before and after LD L-A, changes in coronary reserve due to this abrupt LDL cholesterol re duction could be measured both quantitatively and non-invasively. In n ine patients (six women, three men) with documented coronary artery di sease and hypercholesterolemia, PET was carried out immediately before and 18-20 h after LDL-A. A reduction in LDL cholesterol (from 194 +/- 38 to 81 +/- 20 mg/dl), facilitated significant improvement in myocar dial blood flow (MBF) (173 +/- 63 versus 226 +/- 79 ml/min per 100 g) after pharmacologic recruitment of coronary flow capacity (dipyridamol e stress), coronary flow reserve (CFR) (1.91 +/- 0.68 versus 2.48 +/- 0.68) and minimum coronary resistance (MCR) (0.61 +/- 0.18 versus 0.43 +/- 0.16 mmHg/100 g per min per ml) within 24 h. Plasma viscosity was reduced slightly, by 6.6%. Probably for the first time, a 30% improve ment in coronary vasodilatation capacity could be demonstrated quantit atively and non-invasively by PET after a single LDL-A within 24 h. (C ) 1998 Elsevier Science Ireland Ltd. All rights reserved.