Huang Hui-Chun, Suen Pei-Chin, Liu Jih-Shin, Chen Cheryl Chia-Hui, Liu Yen-Bin, Chen Chu-Chih
Division of Cardiology, Department of Internal Medicine, National Taiwan University Hospital, National Taiwan University College of Medicine, Taipei, Taiwan.
Department of Nursing, College of Medicine, National Taiwan University, National Taiwan University Hospital, Taipei, Taiwan.
Front Med (Lausanne). 2021 Jan 15;7:624343. doi: 10.3389/fmed.2020.624343. eCollection 2020.
Electrical storm (ES) has profound psychological effects and is associated with a higher mortality in patients with implantable cardioverter-defibrillator (ICD). Assessing the incidence and features of ES, is vital. Previous studies have shown winter peaks for ventricular tachyarrhythmia (VTA) in ICD patients. However, the effects of heat with a high relative humidity remain unclear. Thus, this study aimed to assess the nonlinear and lagged effects of apparent temperature [or heat index (HI)] on VTA among patients with and without ES after ICD implantation. Of 626 consecutive patients who had ICDs implanted from January 2004 to June 2017 at our hospital, 172 who experienced sustained VTAs in ICD recording were analyzed, and their clinical records were abstracted to assess the association between VTA incidence and HI by time-stratified case-crossover analysis. Cubic splines were used for the nonlinear effect of HI, with adjustment for air pollutant concentrations. A significant seasonal effect for ES patients was noted. Apparent temperature, but not ambient temperature, was associated with VTA occurrences. The low and high HI thresholds for VTA incidence were <15° and >30°C, respectively, with a percentage change in odds ratios of 1.06 and 0.37, respectively, per 1°C. Lagged effects could only be demonstrated in ES patients, which lasted longer for low HI (in the next 4 days) than high HI (in the next 1 day). VTA occurrence in ICD patients was strongly associated with low HI and moderately associated with high HI. Lagged effects of HI on VTA were noted in patients with ES. Furthermore, patients with ES were more vulnerable to heat stress than those without ES. Patients with ICD implantation, particularly in those with ES, should avoid exposure to low and high HI to reduce the risk of VTAs, improve quality of life and possibly reduce mortality.
电风暴（ES）具有深远的心理影响，并且与植入式心脏复律除颤器（ICD）患者的较高死亡率相关。评估ES的发生率和特征至关重要。先前的研究表明，ICD患者的室性快速心律失常（VTA）在冬季出现高峰。然而，高相对湿度的热效应仍不清楚。因此，本研究旨在评估体感温度[或热指数（HI）]对ICD植入后有和没有ES的患者VTA的非线性和滞后效应。在2004年1月至2017年6月期间于我院连续植入ICD的626例患者中，对172例在ICD记录中经历持续性VTA的患者进行了分析，并提取了他们的临床记录，通过时间分层病例交叉分析评估VTA发生率与HI之间的关联。使用三次样条曲线来分析HI的非线性效应，并对空气污染物浓度进行了调整。 注意到ES患者有显著的季节效应。体感温度而非环境温度与VTA的发生相关。VTA发生率的低HI阈值和高HI阈值分别<15°C和>30°C，每升高1°C，优势比的变化百分比分别为1.06和0.37。滞后效应仅在ES患者中得到证实，低HI（在接下来的4天）的持续时间比高HI（在接下来的1天）更长。ICD患者中VTA的发生与低HI密切相关，与高HI中度相关。在ES患者中注意到HI对VTA的滞后效应。此外，与没有ES的患者相比，ES患者更容易受到热应激的影响。植入ICD的患者，特别是那些患有ES的患者，应避免暴露于低HI和高HI环境，以降低VTA风险，提高生活质量并可能降低死亡率。
