Background:

Flecainide is a useful antiarrhythmic for atrial fibrillation (AF). However, because of ventricular proarrhythmia risk, a history of myocardial infarction (MI) or coronary artery disease (CAD) is a flecainide exclusion, and stress testing is used to exclude ischemia. We assessed whether absent/mild coronary artery calcium (CAC) can supplement or avoid the need for stress testing.

Methods:

We assessed ischemic burden using regadenoson Rb-82 PET/CT in 1372 AF patients ≥50 years old without symptoms or signs of clinical CAD. CAC was determined qualitatively by low dose attenuation computed tomography (CT) (n = 816) or by quantitative CT (n = 556). Ischemic burden and clinical outcomes were compared by CAC burden.

Results:

Patients with CAC absent or mild (n = 766, 57.2%) were younger, more frequently female, and had higher BMI but lower rates of diabetes, hypertension, and dyslipidemia. Average ischemic burden was lower in CAC-absent/mild patients, and CAC-absent/mild patients showed greater coronary flow reserve, had fewer referrals for coronary angiography, and less often had obstructive CAD. Revascularization at 90 days was lower, and the rate of longer-term major adverse cardiovascular events was favorable.

Conclusions:

An easily administered, inexpensive, low radiation CAC scan can identify a subset of flecainide candidates with a low ischemic burden on PET stress testing that rarely needs coronary angiography/intervention and has favorable outcomes. Absent or mild CAC-burden combined with other clinical information may avoid or complement routine stress testing. However, additional, ideally randomized and multicenter trials are indicated to confirm these findings before replacing stress testing with CAC screening in selecting patients for flecainide therapy in clinical practice.

中文翻译：

---

缺乏或轻度冠状动脉钙可预测考虑接受氟卡尼治疗的患者的低风险压力测试结果和结果

背景：

氟卡尼是治疗心房颤动 (AF) 的有用抗心律失常药。然而，由于室性心律失常风险，心肌梗死（MI）或冠状动脉疾病（CAD）病史排除氟卡尼，负荷试验用于排除缺血。我们评估了缺席/轻度冠状动脉钙 (CAC) 是否可以补充或避免压力测试的需要。

方法：

我们使用热加腺苷 Rb-82 PET/CT 评估了 1372 名 50 岁以上无临床 CAD 症状或体征的 AF 患者的缺血负荷。CAC 通过低剂量衰减计算机断层扫描 (CT) (n = 816) 或定量 CT (n = 556) 定性确定。通过 CAC 负荷比较缺血负荷和临床结果。

结果：

CAC 缺失或轻度的患者（n = 766, 57.2%）更年轻，女性更常见，BMI 较高，但糖尿病、高血压和血脂异常的发生率较低。CAC 缺失/轻度患者的平均缺血负荷较低，CAC 缺失/轻度患者表现出更大的冠状动脉血流储备，较少转诊进行冠状动脉造影，并且较少发生阻塞性 CAD。90 天血运重建率较低，长期主要心血管不良事件发生率较高。

结论：

一种易于管理、廉价、低辐射的 CAC 扫描可以识别氟卡尼候选物的子集，在 PET 负荷测试中具有低缺血负担，很少需要冠状动脉造影/干预，并且具有良好的结果。缺乏或轻度 CAC 负担与其他临床信息相结合可以避免或补充常规压力测试。然而，在临床实践中选择氟卡尼治疗患者时，在用 CAC 筛查替代压力测试之前，需要进行额外的、理想的随机和多中心试验来确认这些发现。