Setoguchi Akito, Takeno Masayoshi, Kusumoto Saburo, Nunohiro Tatsuya, Maemura Koji
Department of Cardiovascular Medicine, Nagasaki Harbor Medical Center, Nagasaki, JPN.
Department of Cardiovascular Medicine, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, JPN.
Cureus. 2025 Aug 12;17(8):e89935. doi: 10.7759/cureus.89935. eCollection 2025 Aug.
Intravascular lithotripsy (IVL) delivers acoustic shockwaves to fracture coronary calcifications and optimize stent expansion, yet side branch (SB) occlusion after IVL is rarely documented. We report the case of an 80-year-old man with prior stents in the distal right coronary and proximal left circumflex arteries who underwent elective percutaneous coronary intervention for 75% proximal left anterior descending artery (LAD) stenosis supplying four diagonal branches: the first (D1), second (D2), third (D3), and fourth (D4) diagonal branches. The instantaneous wave-free ratio was 0.82 and the fractional flow reserve was 0.77, both indicating ischemia. Optical coherence tomography (OCT) demonstrated severe, long calcification (calcification score 4; maximum arc 330°; thickness 12.1 mm; length 38.2 mm; minimum lumen area 1.46 mm²), and IVL was selected over rotational atherectomy or scoring balloon angioplasty due to high calcification score and wire bias considerations. Eight cycles of IVL with a 2.5/12 mm balloon were applied from the D4 bifurcation to proximal LAD, followed by eight cycles with a 3.0/12 mm balloon, increasing the minimum lumen area to 3.31 mm². After pre-dilation with a 2.5/13 mm scoring balloon distally and a 3.0/15 mm non-compliant balloon proximally, a 2.5/38 mm everolimus-eluting stent was implanted, and the proximal segment was post-dilated with a 3.0/15 mm non-compliant balloon. Immediately after post-dilation, the patient developed chest pain and ST-segment elevation; angiography showed new occlusion of the third diagonal branch (D3, thrombolysis in myocardial infarction (TIMI) 0) and flow reduction in the first diagonal branch (D1) from TIMI 3 to TIMI 1, while all other branches maintained TIMI 3 flow. Wire recrossing and kissing balloon inflation (1.5/10 mm semi-compliant in D3, 3.0/15 mm non-compliant in the main vessel) restored TIMI 3 flow in D3 and relieved symptoms, whereas D1 remained TIMI 1 but asymptomatic. No protective wiring had been performed initially as the affected SB was <1.5 mm, but the subsequent ischemic event indicated it should be considered a significant branch. Angiography before and after IVL showed no change suggestive of SB risk, whereas OCT performed immediately after IVL revealed new protrusion of fractured calcifications into the D1 and D3 ostia, which was considered the cause of the subsequent side branch occlusion. IVL-related SB occlusion is an extremely rare complication in the literature, but meticulous pre-procedural OCT assessment and consideration of protective wiring in high-risk bifurcation lesions may help predict and prevent this event.
血管内碎石术（IVL）通过传递声波冲击波来破碎冠状动脉钙化灶并优化支架扩张效果，然而IVL术后出现的分支血管（SB）闭塞情况鲜有报道。我们报告了一例80岁男性患者，其右冠状动脉远端和左回旋支近端曾植入支架，此次因左前降支（LAD）近端75%狭窄并为四条对角支供血而接受择期经皮冠状动脉介入治疗，这四条对角支分别为第一对角支（D1）、第二对角支（D2）、第三对角支（D3）和第四对角支（D4）。瞬时无波比值为0.82，血流储备分数为0.77，均提示存在心肌缺血。光学相干断层扫描（OCT）显示存在严重的长段钙化（钙化积分4分；最大弧度330°；厚度12.1mm；长度38.2mm；最小管腔面积1.46mm²），鉴于钙化积分较高以及导丝偏向等因素，相较于旋磨术或刻痕球囊血管成形术，最终选择了IVL。使用2.5/12mm球囊从D4分叉处至LAD近端进行了8个周期的IVL治疗，随后使用3.0/12mm球囊进行了8个周期的治疗，使最小管腔面积增加至3.31mm²。在远端使用2.5/13mm刻痕球囊、近端使用3.0/15mm非顺应性球囊进行预扩张后，植入了一枚2.5/38mm依维莫司洗脱支架，近端节段使用3.0/15mm非顺应性球囊进行了后扩张。后扩张后即刻，患者出现胸痛及ST段抬高；血管造影显示第三对角支（D3）出现新的闭塞（心肌梗死溶栓治疗（TIMI）血流分级0级），第一对角支（D1）血流从TIMI 3级降至TIMI 1级，而其他所有分支的TIMI血流均维持在3级。导丝重新通过病变部位并进行球囊对吻扩张（D3使用1.5/10mm半顺应性球囊，主血管使用3.0/15mm非顺应性球囊）后，D3的TIMI血流恢复至3级且症状缓解，而D1仍为TIMI 1级但无症状。最初由于受累分支血管直径<1.5mm未进行保护性导丝置入，但随后发生的缺血事件表明应将其视为重要分支血管。IVL术前及术后血管造影均未显示提示分支血管风险的变化，而IVL术后即刻进行的OCT显示破碎的钙化灶新突出至D1和D3开口处，这被认为是随后分支血管闭塞的原因。IVL相关的分支血管闭塞在文献中是一种极其罕见的并发症，但细致全面的术前OCT评估以及对高危分叉病变考虑进行保护性导丝置入可能有助于预测和预防这一事件。
