Remote ischaemic preconditioning reduces myocardial injury in patients undergoing heart valve surgery: randomised controlled trial.

OBJECTIVE: To determine whether remote ischaemic preconditioning (RIPC) is cardioprotective in patients undergoing heart valve replacement. DESIGN: Single-blinded, randomised controlled trial. SETTING: Tertiary referral hospital in China. PATIENTS: Adult patients (31-72 years) undergoing mitral valve, aortic valve or tricuspid valve surgery. INTERVENTIONS: Patients were randomised to either the RIPC (n=38) or control (n=35) group. After induction of anaesthesia, patients in the RIPC group underwent three 5 min cycles of right upper limb ischaemia, induced by an automated cuff-inflator placed on the upper arm and inflated to 200 mm Hg. Each cycle was interrupted by a 5 min period of reperfusion during which time the cuff was deflated. The control group had only a deflated cuff placed on the upper arm for 30 min. MAIN OUTCOME MEASURES: Serum troponin I concentration was measured before surgery and at 6, 12, 24, 48, and 72 h postoperatively. The cardiac function of all patients was followed postoperatively. RESULTS: Troponin I concentration was reduced in the RIPC group (398.7±179.3 µg/l) compared with the control group (708.4±242.5 µg/l). Mean difference was 309.7±50.8 (95% CI 210.1 to 409.3, p<0.0001). A greater improvement in postsurgical cardiac function was noted in the RIPC group than in the control group. CONCLUSIONS: These data indicate that RIPC reduces myocardial injury and improves cardiac function in patients undergoing heart valve surgery. TRIAL REGISTRATION NUMBER: NCT01175681.

L-arginine restores endothelial nitric oxide synthase-coupled activity and attenuates monocrotaline-induced pulmonary artery hypertension in rats.

L-arginine can attenuate pulmonary hypertension (PH) by a mechanism that are not fully understood. This study investigated the molecule mechanism of L-arginine attenuating PH. Sprague Dawley rats were treated with monocrotaline (MCT) with or without L-arginine for 3 or 5 wk. Right ventricular systolic pressure (RVSP), right heart hypertrophy, survival rate, pulmonary artery wall thickness, nitric oxide (NO) concentration, and superoxide anion (O(2)(*-)) generation in the lung were measured. Expressions of endothelial nitric oxide synthase (eNOS) and heat shock protein 90 (HSP90), phosphorylation of eNOS at Ser(1177), and the association of eNOS and HSP90 in the lung were determined by Western blot and immunoprecipitation experiments. MCT increased RVSP, right heart hypertrophy, mortality, pulmonary artery wall thickness, and O(2)(*-) generation and decreased eNOS and HSP90 expression and association, phosphorylation of eNOS at Ser(1177), and NO production. L-arginine decreased RVSP, right heart hypertrophy, mortality, O(2)(*-) generation, and pulmonary artery wall thickness and increased NO production. L-arginine increased eNOS expression, phosphorylation of eNOS at Ser(1177), and association of eNOS and HSP90 without significantly altering HSP90 expression. L-arginine may act through three pathways, providing a substrate for NO generation, preserving eNOS expression/phosphorylation, and maintaining the association of eNOS and HSP90, which allows restoration of eNOS activity and coupling activity, to maintain the balance between NO and O(2)(*-) and delay the development of PH.

Surgical treatment of congenital artrial septal defect in adults / 中国基层医药

Objective To summarize the clinical expedence in surgical treatment and prognosis of artrial septal defect(ASD)in adults and to know well the surgical indication of ASD in adults.Methods 32 patients over 20 years old with the left to right shunt and preoperative mean pulmonary artery pressure less than 8kPa underwent direct surgical repair for ASD under extra corporeal circulation.Results All patients survived after surgery,there was no surgical mortality in our group.32 patients were followed-up,29 of them with disappearing symptoms and 3 of them still had various symptoms.Conclusion The following condition ASD in adults who have slight to moderate clinical symptoms should be operated:cardiac enlargement eardiothoracic ratio over 50% and pneumonemia in X-ray films;right ventricular hypertrophy with a right axis deviation of incomplete right bundle branch block on the electrocardiogram;diameter of ASD over 1.5cm in ultrasonic cardiogram.