Kwong Evan J, Watson Gage R, Billingsley Ian McAuley, Tauh Keerit
University of British Columbia, Vancouver, British Columbia, Canada.
University of British Columbia, Vancouver, British Columbia, Canada; Kelowna General Hospital, Kelowna, British Columbia, Canada.
JACC Case Rep. 2025 Apr 2;30(7):103406. doi: 10.1016/j.jaccas.2025.103406.
In the post-left internal thoracic artery (LITA)-to-coronary artery bypass graft (CABG) setting, anginal symptoms are associated with the presence of large, unligated LITA side branches. These symptoms are mediated by a variable arterial steal phenomenon.
This report describes an atypical case of ST-segment elevation myocardial infarction (STEMI) following LITA-CABG secondary to a variable arterial steal phenomenon induced by both a branch variant of the LITA and an intercostal artery. Angiography-guided embolization of the branch vessels successfully resolved the patient's ischemia.
STEMI secondary to LITA branch-mediated steal has not been previously reported. This case demonstrates that large LITA side branches can lead to myocardial infarction and that embolization of the relevant side branches is an effective treatment strategy.
TAKE-HOME MESSAGES: Providers should be aware that LITA side branches, if not ligated during surgery, may lead to threatening coronary ischemia. If such side branches cannot be ligated intraoperatively, then intravascular embolization is an effective treatment strategy.
在左乳内动脉（LITA）至冠状动脉旁路移植术（CABG）后，心绞痛症状与未结扎的粗大LITA侧支的存在有关。这些症状由可变的动脉窃血现象介导。
本报告描述了1例LITA-CABG术后发生ST段抬高型心肌梗死（STEMI）的非典型病例，该病例继发于由LITA分支变异和肋间动脉共同引起的可变动脉窃血现象。血管造影引导下对分支血管进行栓塞成功解决了患者的缺血问题。
此前尚未报道过LITA分支介导的窃血继发STEMI的情况。该病例表明，粗大的LITA侧支可导致心肌梗死，对相关侧支进行栓塞是一种有效的治疗策略。
临床医生应意识到，LITA侧支若在手术中未结扎，可能导致危及生命的冠状动脉缺血。如果此类侧支在术中无法结扎，那么血管内栓塞是一种有效的治疗策略。
