Itoh Hideki, Hisamatsu Takashi, Segawa Kazuhiko, Takahashi Toshiaki, Sato Takumi, Takada Hiroto, Kuru Satoshi, Wada Chizu, Suzuki Mikiya, Tamura Takuhisa, Suwazono Shugo, Kimura Koichi, Matsumura Tsuyoshi, Takahashi Masanori P
Division of Patient Safety, Hiroshima University Hospital, 1-2-3 Kasumi, Minami-ku, Hiroshima 734-8551, Japan.
Department of Cardiovascular Medicine, Shiga University of Medical Science, Seta Tsuknowa-cho, Otsu, Shiga 520-2192, Japan.
Eur Heart J Open. 2024 Sep 18;4(5):oeae078. doi: 10.1093/ehjopen/oeae078. eCollection 2024 Sep.
Myotonic dystrophy Type 1 (DM1) is caused by the expansion of CTG repeats (CTGn) in the DM1 protein kinase (DMPK) gene, while it remains unclear whether CTGn may be associated with the incidence of cardiac events or sudden death in Japan as well as Europe. The aim of this study was to investigate the association between CTGn and cardiac involvements.
This cohort study included patients with DM1 who were retrospectively recruited from nine Japanese hospitals specializing in neuromuscular diseases. A total of 496 patients with DM1 who underwent a genetic test in the DMPK gene were analysed. Patients with congenital form or under 15 years old were excluded and patients were assigned into the quartiles. When we compared the incidence of cardiac events including advanced/complete atrioventricular block, pacemaker implantation, and ventricular tachycardias or mortality among four groups, patients with 1300 or longer CTGn experienced composite cardiac events [hazard ratio (HR): 3.19, 95% confidence interval (CI): 1.02-9.99, = 0.014] more frequently and had significantly higher mortality rate (HR: 6.79, 95% CI: 2.05-22.49, < 0.001) than those under 400 CTGn while the rate of sudden death was not significantly different.
Regarding the cardiac events and mortality in patients with DM1, patients with 1300 or longer CTGn are at especially high risk.
1型强直性肌营养不良症（DM1）由DM1蛋白激酶（DMPK）基因中的CTG重复序列（CTGn）扩增引起，然而在日本以及欧洲，CTGn是否与心脏事件或猝死的发生率相关仍不清楚。本研究的目的是调查CTGn与心脏受累之间的关联。
这项队列研究纳入了从9家日本神经肌肉疾病专科医院回顾性招募的DM1患者。对总共496例接受DMPK基因检测的DM1患者进行了分析。排除先天性形式或15岁以下的患者，并将患者分为四分位数。当我们比较四组中包括高度/完全房室传导阻滞、起搏器植入以及室性心动过速等心脏事件的发生率或死亡率时，CTGn为1300或更长的患者发生复合心脏事件的频率更高[风险比（HR）：3.19，95%置信区间（CI）：1.02 - 9.99，P = 0.014]，且死亡率显著更高（HR：6.79，95%CI：2.05 - 22.49，P < 0.001），而猝死率无显著差异。
关于DM1患者的心脏事件和死亡率，CTGn为1300或更长的患者风险尤其高。
