Division of Cardiology, University of British Columbia, Vancouver, British Columbia, Canada.
Cardiology Clinical Academic Group, St. George's University Hospitals NHS Foundation Trust, London, United Kingdom; Institute of Molecular and Clinical Sciences, St. George's University of London, London, United Kingdom.
JACC Clin Electrophysiol. 2019 Apr;5(4):504-512. doi: 10.1016/j.jacep.2019.01.026. Epub 2019 Mar 27.
The authors studied the response rates and relative sensitivity of the most common agents used in the sodium-channel blocker (SCB) challenge.
A type 1 Brugada electrocardiographic pattern precipitated by an SCB challenge confers a diagnosis of Brugada syndrome.
Patients undergoing an SCB challenge were prospectively enrolled across Canada and the United Kingdom. Patients with no prior cardiac arrest and family histories of sudden cardiac death or Brugada syndrome were included.
Four hundred twenty-five subjects underwent SCB challenge (ajmaline, n = 331 [78%]; procainamide, n = 94 [22%]), with a mean age of 39 ± 15 years (54% men). Baseline non-type 1 Brugada ST-segment elevation was present in 10%. A total of 154 patients (36%) underwent signal-averaged electrocardiography, with 41% having late potentials. Positive results were seen more often with ajmaline than procainamide infusion (26% vs. 4%, p < 0.001). On multivariate analysis, baseline non-type 1 Brugada ST-segment elevation (odds ratio [OR]: 6.92; 95% confidence interval [CI]: 3.15 to 15.2; p < 0.001) and ajmaline use (OR: 8.76; 95% CI: 2.62 to 29.2; p < 0.001) were independent predictors of positive results to SCB challenge. In the subgroup undergoing signal-averaged electrocardiography, non-type 1 Brugada ST-segment elevation (OR: 9.28; 95% CI: 2.22 to 38.8; p = 0.002), late potentials on signal-averaged electrocardiography (OR: 4.32; 95% CI: 1.50 to 12.5; p = 0.007), and ajmaline use (OR: 12.0; 95% CI: 2.45 to 59.1; p = 0.002) were strong predictors of SCB outcome.
The outcome of SCB challenge was significantly affected by the drug used, with ajmaline more likely to provoke a type 1 Brugada electrocardiographic pattern compared with procainamide. Patients undergoing SCB challenge may have contrasting results depending on the drug used, with potential clinical, psychosocial, and socioeconomic implications.
研究钠通道阻滞剂（SCB）激发试验中最常用药物的反应率和相对敏感性。
由 SCB 激发试验引发的 1 型 Brugada 心电图模式可诊断为 Brugada 综合征。
在加拿大和英国，前瞻性招募接受 SCB 激发试验的患者。入选标准为：无既往心搏骤停，无家族性心源性猝死或 Brugada 综合征病史。
425 例患者接受 SCB 激发试验（喷他脒 331 例[78%]；普鲁卡因胺 94 例[22%]），平均年龄 39±15 岁（54%为男性）。基线非 1 型 Brugada 型 ST 段抬高占 10%。共 154 例患者（36%）行信号平均心电图检查，其中 41%有晚电位。与普鲁卡因胺输注相比，喷他脒输注时阳性结果更常见（26% vs. 4%，p<0.001）。多变量分析显示，基线非 1 型 Brugada 型 ST 段抬高（比值比[OR]：6.92；95%置信区间[CI]：3.15 至 15.2；p<0.001）和喷他脒的使用（OR：8.76；95%CI：2.62 至 29.2；p<0.001）是 SCB 激发试验阳性结果的独立预测因素。在接受信号平均心电图检查的亚组中，非 1 型 Brugada 型 ST 段抬高（OR：9.28；95%CI：2.22 至 38.8；p=0.002）、信号平均心电图检查的晚电位（OR：4.32；95%CI：1.50 至 12.5；p=0.007）和喷他脒的使用（OR：12.0；95%CI：2.45 至 59.1；p=0.002）是 SCB 结果的强烈预测因素。
SCB 激发试验的结果明显受药物影响，与普鲁卡因胺相比，喷他脒更有可能引发 1 型 Brugada 心电图模式。根据所用药物，接受 SCB 激发试验的患者可能会有不同的结果，这可能具有临床、心理社会和社会经济方面的影响。
