[Effect of simvastatin therapy on endothelial function of hypercholesteremic patients with syndrome X].

INTRODUCTION

Cardiac syndrome X patients often have both reduced coronary circulation and impaired systemic endothelial function.

AIMS

The aim of our study was to assess the effect of chronic statin therapy on exercise-induced "ischemic like" ST segment depression and on systemic endothelial function in cardiac syndrome X patients with hypercholesterolemia.

PATIENTS/METHODS: In 25 hypercholesterolemic patients (15 males, mean age 55 +/- 3 years) with a normal coronary angiogram and positive exercise ECG test (> 0.1 mV ST segment depression) the flow mediated dilatation (FMD) was assessed by measuring the change in brachial artery diameter in response to hyperemic flow by vascular ultrasound. All patients were treated with 20 mg simvastatin in duration of 12 weeks. Following the treatment the exercise ECG and the vascular ultrasound studies were repeated.

RESULTS

There was a significant decrease in total serum cholesterol level (baseline = 5.82 +/- 0.19 mmol/L vs. study end = 4.49 +/- 0.17 mmol/L, p < 0.01) and significant increase in the serum HDL level (baseline = 1.05 +/- 0.16 mmol/L vs. study end = 1.11 +/- 0.14 mmol/L, p < 0.01) following the statin treatment. Parallelly brachial artery FMD increased significantly (baseline = 3.97 +/- 0.91% vs. study end = 6.84 +/- 0.89%, p < 0.05). Responses to nitroglycerin were similar during the time course of the study. The ischemia free stress test time was also higher at the study end (baseline = 5.18 +/- 2.01 min vs. study end = 6.01 +/- 1.94 min, p < 0.001).

CONCLUSIONS

The chronic statin therapy exerts beneficial effects both on systemic and coronary endothelial function in hypercholesterolemic patients with cardiac syndrome X.