Beneficial Effects of β-adrenergic Blockade in Coronary Artery Surgery: Clinical Research

In an attempt to resolve the controversy concerning use of β-adrenoceptor blockade in patients undergoing coronary artery revascularization, 40 consecutive patients with ischaemic heart disease receiving chronic β-adrenergic blocking therapy (study group) were entered into a randomized trial and were compared with 40 patients receiving no β-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 β 1 -adrenergic receptors induced by β-adrenergic blockade, and an increase in the level of catecholamines in the early postoperative period.