EFFICACY OF IVABRADINE, METOPROLOL ALONE VS IVABRADINE PLUS METOPROLOL (COMBINATION) FOR HEART RATE REDUCTION AND HEART RATE VARIABILITY DURING COMPUTED TOMOGRAPHY CORONARY ANGIOGRAPHY: A RANDOMIZED CONTROLLED TRIAL

Abstract

Objective: To establish the efficacy of Ivabradine, Metoprolol alone vs Ivabradine plus Metoprolol for the heart rate reduction in patients undergoing computed tomography coronary angiography.

Study Design: Randomized controlled trial.

Place and Duration of Study: Armed Forces Institute of Cardiology & National Institute of Heart Disease, Rawalpindi, from Oct 2017 to Jan 2018.

Material and Methods: Patients undergoing first CTCA angiography meeting inclusion criteria with heart rates more than 80 beats/min were included. Patients were randomized into three groups using computer generated random tables. Arm A was administered Ivabradibe plus placebo, Arm B was administered Metoprolol plus plecebo while Arm C was administered Ivabradine plus Metoprolol one hour before the scan. All the groups had scans under strictly similar conditions. Heart rate before and during scan along with heart rate variability were recorded.

Results: A total of 165 patients were included in the study, 55 patients in each group. Mean age of patients was 53.5 ± 0.5 years. One hundred and seven (64.8%) were males while patients 58 (35.2%) were females. Risk factor profile was almost similar in all the groups. Heart rate reduction in Arm A was 18.3 ± 3.8, in Arm B was 12.6 ± 5.8 and in Arm C was 24 ± 3.0 (p=0.02). Heart rate variability in Arm A was 3.2, in Arm B was 4.0 and in Arm C was 1.8 (p=0.001). Arm C had significantly lower heart rate and significantly less heart rate variability followed by Arm A then Arm B.

Conclusion: Ivabradine is an established safe and effective heart rate-reducing agent in patients undergoing CTCA, particularly in those patients, who cannot tolerate beta-blockers or calcium-channel blockers due to their side effects.