Effect of pentoxifylline on red cell flexibility in arterio-sclerotic patients and in patients with heart valve prosthesis.

Red cell flexibility (RCF) was studied in 40 patients with severe occlusive arterio-sclerotic disease of the lower extremities (Group I) and in 17 patients with aortic or mitral valve prosthesis (Group II). RCF was studied in terms of rigidity and fragility using a filtration method. Pentoxifylline, which according to our previous observations increases the flexibility of red cells in healthy subjects, also markedly improved RCF in Group I, particularly in terms of fragility. The pentoxifylline-induced increase in RCF was less marked in Group II; only the rigidity parameter was significantly decreased. Reid et al [11] reported decreased deformability of red cells in patients with intermittent claudication. Since then a few other studies have been published, in which decreased red cell flexibility (RCF) was observed in patients with diabetic vascular disease [1, 4, 9, 12] and cerebral arteriosclerosis [10]. The objective of this study was to compare RCF in patients with widespread arteriosclerosis and heart valve prosthesis, the latter condition inducing a 'pure' mechanical red cell injury. Both patient groups were also studied after the administration of pentoxifylline, a drug known to improve the flexibility of normal red cells--see [6].