Effect of Pulmonary Artery Pressure on Changes in Right Ventricular Function according to Norepinephrine Infusion in Patients with Valvular Heart Disease

Background: Increasing coronary perfusion pressure by using a vasopressor is one of the important treatment strategies in pulmonary hypertension. In present study, we evaluated whether chronic pulmonary hypertension influences the effect of norepinephrine (NE) on right ventricular function and hemodynamic variables in patients with valvular heart disease. Methods: Forty eight patients undergoing valve replacement surgery were divided into two groups according to pulmonary artery pressure, i.e., a control (n = 28) and a pulmonary hypertension group (n = 20). A thermodilution pulmonary artery catheter for continuous monitoring of cardiac output, right ventricular (RV) ejection fraction and RV volume was inserted before the induction of anesthesia. When systemic hypotension occurred following induction of anesthesia, norepinephrine was infused at rates of 0.03 and then 0.06/kg/min for 10 minutes, respectively and hemodynamic variables were measured after anesthesia induction, and at the end point of each infusion rate. Results: No significant differences occurred in systemic or pulmonary hemodynamic variables according to the infusion of norepinephrine between the two groups. And, no significant changes were observed in right ventricular performance according to the infusion of norepinephrine in two groups. Conclusions: Norepinephrine did not show different systemic or pulmonary hemodynamic effects in patients with or without chronic pulmonary hypertension. Norepinephrine did not increase the right ventricular ejection fractions or cardiac outputs of patients with chronic pulmonary hypertension.