Abstract：
BACKGROUND: Coronary microvascular dysfunction (CMD) has been proposed as a crucial factor in the pathophysiology of Takotsubo syndrome (TTS). The angiography-derived index of microcirculatory resistance (caIMR) offers an alternative to conventional hyperemic wire-based IMR to assess CMD. We aimed to evaluate CMD\'s prevalence, transience, and impact on in-hospital outcomes in TTS.
METHODS: All three coronary arteries of 96 patients with TTS were assessed for their coronary angiography derived Index of microcirculatory Resistance (caIMR) and compared to non-obstructed vessels of matched patients with ST-elevation myocardial infarction. Further, the association between caIMR and the TTS-specific combined in-hospital endpoint of death, cardiac arrest, ventricular arrhythmogenic events and cardiogenic shock was investigated.
RESULTS: Elevated IMR was present in all TTS patients, with significantly elevated caIMR values in all coronary arteries compared to controls. CaIMR did not differ between apical and midventricular TTS types. CaIMR normalized in TTS patients with follow-up angiographies performed at a median of 28 months (median caIMR at event vs follow-up: LAD 34.8 [29.9-41.1] vs 20.3 [16.0-25.3], p < 0.001; LCX: 38.7 [32.9-50.1] vs 23.7 [19.4-30.5], p < 0.001; RCA: 31.7 [25.0-39.1] vs 19.6 [17.1-24.0], p < 0.001). The extent of caIMR elevation significantly correlated with the combined in-hospital endpoint (p = 0.036).
CONCLUSIONS: TTS patients had evidence of elevated caIMR in at least one coronary artery with a trend towards higher LAD caIMR in apical type TTS and normalization after recovery. Furthermore, extent of caIMR elevation was associated with increased risk of in-hospital MACE of TTS patients.
METHODS: All three coronary arteries of 96 patients with TTS were assessed for their coronary angiography derived Index of microcirculatory Resistance (caIMR) and compared to non-obstructed vessels of matched patients with ST-elevation myocardial infarction. Further, the association between caIMR and the TTS-specific combined in-hospital endpoint of death, cardiac arrest, ventricular arrhythmogenic events and cardiogenic shock was investigated.
RESULTS: Elevated IMR was present in all TTS patients, with significantly elevated caIMR values in all coronary arteries compared to controls. CaIMR did not differ between apical and midventricular TTS types. CaIMR normalized in TTS patients with follow-up angiographies performed at a median of 28 months (median caIMR at event vs follow-up: LAD 34.8 [29.9-41.1] vs 20.3 [16.0-25.3], p < 0.001; LCX: 38.7 [32.9-50.1] vs 23.7 [19.4-30.5], p < 0.001; RCA: 31.7 [25.0-39.1] vs 19.6 [17.1-24.0], p < 0.001). The extent of caIMR elevation significantly correlated with the combined in-hospital endpoint (p = 0.036).
CONCLUSIONS: TTS patients had evidence of elevated caIMR in at least one coronary artery with a trend towards higher LAD caIMR in apical type TTS and normalization after recovery. Furthermore, extent of caIMR elevation was associated with increased risk of in-hospital MACE of TTS patients.
摘要：
背景：冠状动脉微血管功能障碍（CMD）已被认为是Takotsubo综合征（TTS）病理生理学中的关键因素。血管造影得出的微循环阻力指数（caIMR）为传统的基于充血导线的IMR提供了一种替代方法来评估CMD。我们的目的是评估CMD的患病率，短暂性,以及对TTS住院结局的影响。
方法：对96例TTS患者的所有3条冠状动脉进行了冠状动脉造影衍生的微循环阻力指数（caIMR）评估，并与ST段抬高型心肌梗死患者的非阻塞血管进行比较。Further,caIMR与TTS特异性合并院内死亡终点之间的关联，心脏骤停,研究室性心律失常事件和心源性休克.
结果：所有TTS患者均存在IMR升高，与对照组相比，所有冠状动脉的caIMR值均显着升高。心尖和中室TTS类型之间的CaIMR没有差异。在中位28个月进行随访血管造影的TTS患者中，CaIMR恢复正常（事件与随访时的中位caIMR：LAD34.8[29.9-41.1]vs20.3[16.0-25.3]，p<0.001；LCX：38.7[32.9-50.1]vs23.7[19.4-30.5]，p<0.001；RCA：31.7[25.0-39.1]vs19.6[17.1-24.0]，p<0.001)。caIMR升高的程度与合并的院内终点显著相关(p=0.036)。
结论：TTS患者有至少一条冠状动脉caIMR升高的证据，在心尖型TTS中，有LADcaIMR升高的趋势，恢复后恢复正常。此外，caIMR升高程度与TTS患者院内MACE风险增加相关.
方法：对96例TTS患者的所有3条冠状动脉进行了冠状动脉造影衍生的微循环阻力指数（caIMR）评估，并与ST段抬高型心肌梗死患者的非阻塞血管进行比较。Further,caIMR与TTS特异性合并院内死亡终点之间的关联，心脏骤停,研究室性心律失常事件和心源性休克.
结果：所有TTS患者均存在IMR升高，与对照组相比，所有冠状动脉的caIMR值均显着升高。心尖和中室TTS类型之间的CaIMR没有差异。在中位28个月进行随访血管造影的TTS患者中，CaIMR恢复正常（事件与随访时的中位caIMR：LAD34.8[29.9-41.1]vs20.3[16.0-25.3]，p<0.001；LCX：38.7[32.9-50.1]vs23.7[19.4-30.5]，p<0.001；RCA：31.7[25.0-39.1]vs19.6[17.1-24.0]，p<0.001)。caIMR升高的程度与合并的院内终点显著相关(p=0.036)。
结论：TTS患者有至少一条冠状动脉caIMR升高的证据，在心尖型TTS中，有LADcaIMR升高的趋势，恢复后恢复正常。此外，caIMR升高程度与TTS患者院内MACE风险增加相关.
