Efficacy of siloenafil in the management of severe pulmonary hypertension in patients with rheumatic mitral valve disease undergoing mitral valve surgery

Rheumatic heart disease remains a major health issue in developing countries, and is commonly complicated with pulmonary hypertension. Phosphodiesterase 5 inhibitors selectively inhibit PDE5 abundantly located in the pulmonary vasculature, leading to pulmonary vasodilatation without significant systemic effects. This study aims to investigate the effect of sildenafil, given in a single dose through the nasogastric tube after induction of anesthesia, on hemodynamic parameters in patients with severe pulmonary hypertension secondary to rheumatic mitral valve disease. Thirty adult patients, males and females, with severe pulmonary hypertension [PASP > 60 mmHg] secondary to mitral valve disease and scheduled for mitral valve surgery were randomly allocated to receive either 50 mg of sildenafil [group S] or placebo [group C] through the nasogastric tube immediately after induction of anesthesia. Mean arterial pressure [MAP], systolic [PASP] and mean [MPAP] pulmonary artery pressure values, pulmonary vascular resistance index [PVRI], systemic vascular resistance index [SVRI], and cardiac index [Cl] were assessed before sildenafil administration [Tl], 30 min after administration [T2], 30 min after weaning from cardiopulmonary bypass [T3], 1, 2, and 6 hours postoperatively [T4, T5, and T6 respectively]. Right ventricular fractional area change [RVFAC] was assessed by transesophageal echocardiography at the same timings. PASP was significantly lower in group S compared to group C at T2, T3, and 4 [p<0.05]. Similarly, MPAP was significantly lower in group S compared to group S at T2 and T3 [p<0.05]. PVRI was significantly lower in group S compared to group C at T2 and T3 [p<0.05]. RVFAC was significantly higher in group S compared to group C at T2 and T3 [p<0.05]. There was no difference between both groups in SVRI or Cl. Sildenafil has resulted in a significant reduction in systolic and mean pulmonary artery pressures, as well as PVRI. This has resulted in improvement in right ventricular systolic function without any systemic effects. It is concluded that sildenafil can be very useful in patients with severe pulmonary hypertension undergoing valve surgery

comparative study between levosimendan and ephedrine-calcium in patients undergoing off-pump coronary artery bypass grafting

Background: Many adult patients require temporary inotropic support after cardiac surgery. However, cardiac displacement and manipulation during OPCAB may cause some hemodynamic alterations. So, prophylactic usage of inotropic agents would be mandatory even in patients with normal left ventricular function. The aim of our study is to compare between levosimendan and ephedrine-calcium as inotropic agents during OPCAB in patients with normal left ventricular function

Methods: 24 patients with normal ventricular function included in this randomized controlled trial, were divided into 2 groups: Group A [n=12] received ephedrine-calcium boluses immediately prior to revascularization. Group B [n=12], received 12ug/kg of levosimendan over a period of 15 minutes, immediately after induction of anesthesia. The heart rate, cardiac index, stroke volume index, and left ventricular ejection fraction were measured before and 10 and 60 minutes after the drugs administration as well as 2 hours postoperatively

Results: Heart rate was significantly higher in the calcium-ephedrine group than in the levosimendan one after 10 and 60 minutes from the beginning of revascularization [P<0.05]. Compared with ephedrine-calcium group, cardiac index was significantly higher 10, 60 minutes and 2 hours postoperative [p< 0.05] after administration of levosimendan. Stroke volume index was significantly higher 10 minutes after levosimendan administration [p< 0.05]. Left ventricular ejection fraction increased significantly after 60 minutes, and 2 hours postoperative in the levosimendan group [P<0.05]

Conclusion: Levosimendan in a dose of 12 ug/kg over a period of 15 minutes enhances the left ventricular performance during off-pump coronary artery bypass grafting in patients with normal preoperative left ventricular function, better than calcium-ephedrine with neutral effect on myocardial energy