Association between pre-PTCA blood haemoglobin concentration and the risk of symptomatic restenosis after successful PTCA of primary coronary stenoses.

BACKGROUND: Thrombus formation at the dilation site has been suggested to initiate the restenosis process after percutaneous transluminal coronary angioplasty (PTCA). High haemoglobin concentrations may predispose to thrombus formation by increasing blood viscosity, slowing coronary blood flow and increasing thrombocyte adhesion. METHODS: Pre-PTCA blood haemoglobin concentrations (Hb) in 44 patients with symptomatic restenosis > or = 50% of the vessel diameter (Group A) were compared with Hb in the remaining 215 patients in a consecutive study population (Group B). RESULTS: Median Hb (range) was 149 (119-164) g/l in Group A and 142 (117-164) g/l in Group B, P = 0.004. Odds ratio (95% CI) for symptomatic restenosis was 3.22 (1.62-6.42) when Hb was dichotomised according to the median in the entire material. Hb, but not sex was a significant risk factor in multivariate analysis. CONCLUSION: Hb is a hitherto not recognized factor associated with the risk of symptomatic restenosis after PTCA and may be a link coupling male sex with increased risk of restenosis.

Renal artery stenosis in patients with peripheral vascular disease and its correlation to hypertension. A retrospective study.

To estimate the frequency of renal artery stenosis, and to detect the correlation between renal artery stenosis and hypertension, 450 consecutive patients with peripheral vascular disease (PVD) were selected. All subjects had undergone aorto-femoral conventional angiography. For a possible association with renal artery stenosis, risk factors, clinical and angiographical variables were evaluated e.g.: age, sex, diabetes mellitus, smoking habits, use of antihypertensive drugs, serum creatinine, serum cholesterol, ECG pathology, side of the renal artery lesion, bilateral stenoses, post-stenotic dilatation, number of renal arteries, aortic atherosclerosis, size of the kidneys and angiography induced renal dysfunction. Renal artery stenosis (RAS) was found in 49.1%, 117 patients had a moderate and 104 had a severe stenosis. Of the 221 patients with a renal artery lesion, 44 were normotensive, 177 hypertensive. Hypertension was significantly correlated to RAS. An association was also found for age over 70 years, smoking and pathologic ECG. It is concluded that renal artery stenosis is very common in a population with peripheral vascular disease, and the results achieved from this study makes it worthwhile to identify possible functional markers in a prospective study.