França Neto Olímpio R, Fernandes-Silva Miguel M, Cerci Rodrigo J, Cunha-Pereira Carlos A, Masukawa Margaret, Vitola João V
Quanta Diagnostico Por Imagem, 1000 Almirante Tamandaré Street, Curitiba, PR, 80045-170, Brazil.
Cardiol Ther. 2024 Jun;13(2):341-357. doi: 10.1007/s40119-024-00363-8. Epub 2024 Mar 22.
Ivabradine reduces heart rate (HR), episodes of angina, and nitrate consumption, and increases exercise capacity in patients with chronic angina (CA). In this exploratory study, myocardial perfusion scintigraphy (MPS) was used to evaluate changes in the percentage of myocardial ischemia after ivabradine therapy in patients with CA.
This prospective, open-label, single-arm study included patients with CA receiving maximum tolerated doses of beta blockers, who had a resting HR ≥ 70 bpm and had experienced ischemia according to MPS during an exercise test at baseline. Participants received ivabradine 5 mg twice daily (titrated according to HR) concomitant with beta blockers. A second MPS was performed after 3 months, without interruption of treatment with beta blockers or ivabradine. The primary outcome was change in the percentage of myocardial ischemia from baseline to 3 months. Time to ischemia during the exercise test, the proportion of patients presenting angina during the exercise test, and health status, assessed using the seven-item Seattle Angina Questionnaire-7 (SAQ-7), were also evaluated.
Twenty patients (3 females) with a mean (± standard deviation [SD]) age of 62.2 ± 6.5 years were included in the study, of whom 55% had diabetes, 70% had previous myocardial revascularization, and 45% had previous myocardial infarction. The percentage of patients with myocardial ischemia significantly decreased from baseline to 3 months after initiation of treatment with ivabradine (- 2.9%; 95% confidence interval [CI] - 0.3 to - 5.5; p = 0.031). Mean time to appearance of ischemia increased from 403 ± 176 s at baseline to 466 ± 136 s at 3 months after initiation of ivabradine (Δ62 s; 95% CI 18-106 s; p = 0.008), and the proportion of patients experiencing angina during the exercise test decreased from 40% at baseline to 5% also at 3 months (p = 0.016). Mean resting HR decreased from 76 ± 7 bpm at baseline to 55 ± 8 bpm at 3 months (p < 0.001). The mean SAQ-7 summary score improved from 69 ± 21 at baseline to 83 ± 12 at 3 months (p = 0.001). No serious adverse effects were reported.
Ivabradine added to beta blockers was associated with a reduction in detectable myocardial ischemia by MPS in patients with CA. Infographic available for this article.
The trial has been retrospectively registered with the Brazilian Registry of Clinical Trials (REBEC) under the following number RBR-5fysqrh (date of registration: 30 November 2023).
伊伐布雷定可降低慢性心绞痛（CA）患者的心率（HR）、心绞痛发作次数及硝酸酯类药物用量，并提高运动能力。在这项探索性研究中，采用心肌灌注显像（MPS）评估CA患者接受伊伐布雷定治疗后心肌缺血百分比的变化。
这项前瞻性、开放标签、单臂研究纳入了接受最大耐受剂量β受体阻滞剂治疗的CA患者，这些患者静息心率≥70次/分钟，且在基线运动试验中经MPS检查显示存在缺血。参与者在服用β受体阻滞剂的同时，每日两次服用5mg伊伐布雷定（根据心率调整剂量）。3个月后进行第二次MPS检查，在此期间β受体阻滞剂和伊伐布雷定的治疗均不中断。主要结局指标是从基线到3个月时心肌缺血百分比的变化。同时还评估了运动试验中的缺血时间、运动试验中出现心绞痛的患者比例以及使用七项版西雅图心绞痛问卷（SAQ-7）评估的健康状况。
本研究共纳入20例患者（3例女性），平均年龄（±标准差[SD]）为62.2±6.5岁，其中55%患有糖尿病，70%曾接受过心肌血运重建，45%曾发生过心肌梗死。开始使用伊伐布雷定治疗后，从基线到3个月，心肌缺血患者的百分比显著降低（-2.9%；95%置信区间[CI]-0.3至-5.5；p=0.031）。开始使用伊伐布雷定后，运动试验中缺血出现的平均时间从基线时的403±176秒增加到3个月时的466±136秒（增加62秒；95%CI 18-106秒；p=0.008），运动试验中出现心绞痛的患者比例也从基线时的40%降至3个月时的5%（p=0.016）。静息心率从基线时的76±7次/分钟降至3个月时的55±8次/分钟（p<0.001）。SAQ-7总分从基线时的69±21分提高到3个月时的83±12分（p=0.001）。未报告严重不良反应。
在β受体阻滞剂基础上加用伊伐布雷定可使CA患者通过MPS检测到的心肌缺血减少。本文配有相关信息图。
该试验已在巴西临床试验注册中心（REBEC）进行回顾性注册，注册号为RBR-5fysqrh（注册日期：2023年11月30日）。
