Ivabradine Versus Beta-Blockers in Patients with Conduction Abnormalities or Left Ventricular Dysfunction Undergoing Cardiac Surgery

Abstract

IntroductionIn patients with conduction abnormalities or left ventricle (LV) dysfunction the use of β-blockers for post cardiac surgery rhythm control is difficult and controversial, with a paucity of information about other drugs such ivabradine used postoperatively. The objective of this study was to compare the efficacy and safety of ivabradine versus metoprolol used perioperatively in cardiac surgery patients with conduction abnormalities or LV systolic dysfunction.MethodsThis was an open-label, randomized clinical trial enrolling 527 patients with conduction abnormalities or LV systolic dysfunction undergoing coronary artery bypass grafting or valvular replacement, randomized to take ivabradine or metoprolol, or metoprolol plus ivabradine. The primary endpoints were the composites of 30-day mortality, in-hospital atrial fibrillation (AF), in-hospital three-degree atrioventricular block and need for pacing, in-hospital worsening heart failure (HF; safety endpoints), duration of hospital stay and immobilization and the above endpoint plus in-hospital bradycardia, gastrointestinal symptoms, sleep disturbances, cold extremities (efficacy plus safety endpoint).ResultsHeart rate reduction and prevention of postoperative AF or tachyarrhythmia with combined therapy was more effective than with metoprolol or ivabradine alone during the immediate postoperative management of cardiac surgery patients. In the Ivabradine group, the frequency of early postoperative pacing and HF worsening was smaller than in the Metoprolol group and in combined therapy group. The frequency of primary combined endpoint was lower in the combined Ivabradine + Metoprolol group compared with the monotherapy groups.ConclusionConsidering efficacy and safety, the cardiac rhythm reduction after open heart surgery in patients with conduction abnormalities or LV dysfunction with ivabradine plus metoprolol emerged as the best treatment in this trial.Electronic supplementary materialThe online version of this article (doi:10.1007/s40119-013-0024-1) contains supplementary material, which is available to authorized users.

Atrial Fibrillation After Coronary Artery Bypass Surgery: Can Ivabradine Reduce Its Occurrence?

“…15 Recently, Iliuta et al reported a significant reduction of postoperative in-hospital "AF or tachyarrhythmias" by a regimen of perioperative ivabradine combined with metoprolol, versus either drug alone, in a selected cohort of patients undergoing cardiac surgery who had conduction abnormalities (first-degree atrioventricular block or bundle branch block) or left ventricular dysfunction. 16 However, in that study, the difference in the incidence of in-hospital AF between patients who received the combined regimen and those who received metoprolol alone was very small (8.94% vs. 9.66%, respectively, P value not shown for post hoc analysis); therefore, no firm conclusions could be withdrawn. 16 Instead, the current study enrolled a cohort of unselected patients with relatively few exclusion criteria, and adequate left ventricular systolic function.…”

“…16 However, in that study, the difference in the incidence of in-hospital AF between patients who received the combined regimen and those who received metoprolol alone was very small (8.94% vs. 9.66%, respectively, P value not shown for post hoc analysis); therefore, no firm conclusions could be withdrawn. 16 Instead, the current study enrolled a cohort of unselected patients with relatively few exclusion criteria, and adequate left ventricular systolic function. Moreover, the current study was the first to employ an ambulatory event loop recorder for continuous monitoring and documentation of AF episodes for 15 postoperative days.…”

“…Moreover, we excluded patients with left ventricular systolic dysfunction; our results cannot be extrapolated to this patient subset. Additionally, due to logistic and financial limitations, rhythm monitoring with loop recorders was used for only 15 postoperative days, and the patients had no continuous rhythm monitoring in postoperative days [16][17][18][19][20][21][22][23][24][25][26][27][28][29][30]; rhythm follow-up during that period was performed by weekly clinical follow-up visits. Therefore, some episodes of silent AF might have been missed during this period; this might have caused underestimation of the incidence of postoperative AF.…”

Postoperative atrial fibrillation after off-pump coronary artery bypass grafting

“…The author did not mention about the use of Ivabradine in reducing POAF. Iliuta and Rac-Albu documented that prevention of POAF with combination therapy of metoprolol and ivabradine was more effective than with metoprolol or ivabradine alone during the immediate postoperative management of cardiac surgery patients [2]. Abdel-Salam and Nammas also highlighted that in patients undergoing elective coronary artery bypass grafting, adding ivabradine to β-blockers during the perioperative period was associated with reduced incidence of atrial fibrillation at 30-day follow-up, compared with either medication alone [3].…”

“…Moreover, ivabradine is a selective I f current inhibitor that reduces the heart rate without affecting cardiac contractility by selective sinus node inhibition, and has been shown to be cardioprotective in the failing heart [2,3]. Could the author provide relevant information regarding the use of ivabradine in reduction of POAF.…”