Beneficial effects of beta-adrenergic blockade in coronary artery surgery: clinical research

In an attempt to resolve the controversy concerning use of beta-adrenoceptor blockade in patients undergoing coronary artery revascularization, 40 consecutive patients with ischaemic heart disease receiving chronic beta-adrenergic blocking therapy (study group) were entered into a randomized trial and were compared with 40 patients receiving no beta-blocking therapy (control group). The postoperative requirement for positive inotropic agents between the two groups was compared. The clinical and operative characteristics of the two groups were similar. After surgery, 2% of patients in the study group required positive inotropic agents compared with 18% of those in the control group (P < 0.05). It is concluded that this difference resulted from an increase in density of beta 1-adrenergic receptors induced by beta-adrenergic blockade, and an increase in the level of catecholamines in the early postoperative period.