ADMINISTRATION OF NEBIVOLOL AFTER CORONAR Y-ARTERY BYPASS IN PATIENTSWITH ALTERED LEFT-VENTRICULAR FUNCTION

This prospective, double blind study used invasive monitoring and echo -Doppler techniques to compare the hemodynamic effects of Nebivolol, a new beta(1)-selective blocking agent with those of atenolol in patien ts recovering from coronary artery bypass grafting surgery. Five milli grams nebivolol and 50 mg atenolol equally decreased heart rate (HR) a nd blood pressure (BP) but, nebivolol, in contrast to atenolol, caused no decrease in stroke index (SI), cardiac index (CI), and right ventr icular ejection fraction (RVEF). These differences appeared to be rela ted in part to different peripheral effects of the two agents because nebivolol administration was associated with a reduction in systemic v ascular resistance (SVR). After less than or equal to 10 days of treat ment, acceleration of aortic flow velocity increased and isovolumic re laxation time decreased with nebivolol but not with atenolol treatment . Both drugs were equally well tolerated. Therefore, nebivolol shares most of its effects,vith classical beta(1)-blockers but is devoid of t he potentially harmful effects on cardiac output (CO) and peripheral r esistance.