Hypercoagulability existing in the local left atrium of patient with mitral stenosis

Objective To investigate the pathogenesis of thromboembolism in patients with mitral stenosis in a pre-thrombotic state.Methods The biochemical markers’ levels in plasma for platelet activity [soluble P-selectin (GMP-140)],states of thrombin generation [antithrombin Ⅲ (AT Ⅲ) and protein C (PC)],fibrinolysis [D-dimer (DD), plasminogen activator inhibitor 1 (PAI-1),tissue plasminogen activator (t-PA) and FDP] and von Willebrand factor (vWF) were determined from blood specimens obtained from the femoral veins and arteries and the right and left atria of 43 consecutive patients (20 with atrial fibrillation and 23 with sinus rhythm) with mitral stenosis (MS),undergoing percutaneous mitral valvuloplasty. The same parameters were compared with those of 15 control subjects,who had no detectable heart disease,but with paroxysmal supraventricular tachycardia undergoing radiofrequency catheter ablation of the left accessory pathway through a transseptal passage. Results Blood from the left atrium contained an excessive amount of platelet activity,thrombin generation and fibrinolysis compared with the blood from the right atrium,and the femoral veins and arteries. However blood from the right atrium was much lower in these activities when compared with those from the left atrium,and the femoral veins and arteries in both groups. Compared with those in the control subjects, GMP-140 in the left atrium was significantly higher ( P <0.05) and AT Ⅲ was significantly lower ( P <0.05) in patients with MS. Compared with the patients with MS and spontaneous left atrial echocontrast (LASEC)≤1,the patients with MS and LASEC≥2 had significantly higher levels of GMP-140 in plasma ( P <0.05),and significantly lower levels of AT Ⅲ ( P <0.05) and PC ( P <0.01) levels in the left atrium. However, there were no significant differences between patients with atrial fibrillation and those with sinus rhythm regarding amounts of plasma coagulation markers in the left atrium. Univariate regression analysis revealed that LASEC was negatively correlated with plasma levels of blood from the left atria in the patients with MS. Conclusion Coagulability is increased in the left atria of patients with MS and is positively correlated with LASEC.

Effects of renal artery stenting on renal function and blood pressure in patients with atherosclerotic renovascular disease

Objective To study the effects of percutaneous renal artery intervention on renal function and blood pressure in patients with renal artery stenosis. Methods Eighty-seven patients with severe uni- or bi-lateral renal artery stenosis (luminal diameter narrowing ≥70%) and clinical hypertension received renal artery stenting between January 2002 and December 2002. The changes in blood pressure and serum creatinine level and creatinine clearance (CCr) 48 hours after intervention and during 6 months of follow-up were assessed.Results Renal stenting was performed in 98 stenotic arteries of 87 patients,and the procedural success rate was 100%. Serum creatinine level was slightly elevated from (176±21) μmol/L to (179±11) μmol/L ( P =0.15) 48 hours after the procedure,but significantly decreased to (149±15) μmol/L at 6 months ( P <0.001). CCr was also greatly improved [(37±11) ml/min before versus (51±8) ml/min at 6 months,P <0.001]. During follow-up,61% of the patients experienced a normal renal function. Despite conventional medical treatment,systolic and diastolic blood pressures were also significantly decreased after stenting [(163±23)/(96±13) mm Hg before versus (148±12)/(79±15) mm Hg at 6 months,all P <0.001],and hypertension was well controlled in 67% of the patients at 6 months’ follow-up.Conclusion Renal artery stenting has a high success rate and is effective in improving renal function and blood pressure for patients with severe renal artery stenosis.