Kumar Gautam, Shin Eric Youngyoon, Sachdeva Rajesh, Shlofmitz Evan, Behrens Ann N, Martinsen Brad J, Chambers Jeffrey W
Division of Cardiology, Emory University and Atlanta Veterans Affairs Medical Center, Atlanta, GA, USA.
Section of Interventional Cardiology, MedStar Washington Hospital Center, Washington, DC, USA.
Cardiovasc Revasc Med. 2020 Feb;21(2):164-170. doi: 10.1016/j.carrev.2019.12.027. Epub 2019 Dec 28.
Orbital atherectomy (OA) is an effective method of lesion preparation of severely calcified vessels prior to stent deployment. Long calcified lesions may lead to higher risk of post-procedural complications, yet the optimal treatment strategy has not been established. In this study we sought to determine the safety and efficacy of OA in patients with long (≥25-40 mm) calcified target lesions.
ORBIT II was a single-arm trial that enrolled 443 patients at 49 U.S. sites. De novo, severely calcified coronary lesions were treated with OA prior to stenting. Patients treated with the OA device were stratified into two groups according to target lesion length as visually estimated by the investigator: those with short (<25 mm; N = 314) vs. long (≥25-40 mm; N = 118) lesions. Lesions >40 mm were excluded per protocol. The primary endpoint was the 3-year major adverse cardiac event (MACE) rate, defined as a composite of cardiac death, myocardial infarction (MI), and target vessel revascularization (TVR).
The 3-year MACE rates in patients with short (<25 mm) vs. long (≥25-40 mm) lesions were 21.1% vs. 29.9% respectively (p = 0.055). The rate of cardiac death (6.5% vs. 7.8%, p = 0.592) and TVR (8.5% vs. 13.7%, p = 0.153) did not significantly differ. The rate of MI (CK-MB > 3× ULN) at 3 years was significantly higher in patients with long (≥25-40 mm) lesions (9.0% vs. 17.0%, p = 0.024), with the majority occurring in-hospital (7.0% vs. 13.6%, p = 0.037).
Patients with long (≥25-40 mm) calcified target lesions had similar outcomes in terms of MACE at 3 years despite higher rates of MI, which mostly occurred in-hospital. Using the more contemporary SCAI definition of MI, there was no significant difference in rates of MI between the short (<25 mm) and long (≥25-40 mm) groups. Further studies are warranted to determine how OA compares to focal force balloon angioplasty, rotational atherectomy and other novel treatment options for long severely calcified lesions.
Percutaneous coronary intervention of long calcified lesions is inherently more complex and higher risk and may require more intensive lesion preparation. This sub-analysis of ORBIT II revealed that orbital atherectomy treatment of longer (≥25-40 mm) lesions was associated with a higher rate of MACE at 30 days, but not at 3 years. This difference, however, was driven primarily by a higher in-hospital non-Q-wave MI rate; using the more contemporary SCAI definition of MI, there was no significant difference in rates of MI between the short (<25 mm) and long (≥25-40 mm) groups.
冠状动脉旋磨术（OA）是在支架置入前对严重钙化血管进行病变预处理的有效方法。长段钙化病变可能导致术后并发症风险更高，但最佳治疗策略尚未确立。在本研究中，我们试图确定OA在长（≥25 - 40毫米）钙化靶病变患者中的安全性和有效性。
ORBIT II是一项单臂试验，在美国49个中心招募了443例患者。对初发的严重钙化冠状动脉病变在支架置入前进行OA治疗。根据研究者目测估计的靶病变长度，接受OA装置治疗的患者被分为两组：短病变（<25毫米；n = 314）与长病变（≥25 - 40毫米；n = 118）。按照方案，排除长度>40毫米的病变。主要终点是3年主要不良心血管事件（MACE）发生率，定义为心源性死亡、心肌梗死（MI）和靶血管血运重建（TVR）的复合事件。
短病变（<25毫米）与长病变（≥25 - 40毫米）患者的3年MACE发生率分别为21.1%和29.9%（p = 0.055）。心源性死亡发生率（6.5%对7.8%，p = 0.592）和TVR发生率（8.5%对13.7%，p = 0.153）无显著差异。长病变（≥25 - 40毫米）患者3年时MI（CK - MB>3×ULN）发生率显著更高（9.0%对17.0%，p = 0.024），且多数发生在住院期间（7.0%对13.6%，p = 0.037）。
长（≥25 - 40毫米）钙化靶病变患者3年时MACE结局相似，尽管MI发生率更高，且多数发生在住院期间。采用更现代的SCAI对MI的定义，短病变（<25毫米）组与长病变（≥25 - 40毫米）组的MI发生率无显著差异。有必要进一步研究以确定OA与聚焦力球囊血管成形术、旋切术及其他针对长段严重钙化病变的新型治疗方法相比如何。
长段钙化病变的经皮冠状动脉介入本质上更复杂、风险更高，可能需要更强化的病变预处理。ORBIT II的这项亚分析显示，对较长（≥25 - 40毫米）病变进行冠状动脉旋磨术治疗在30天时MACE发生率较高，但3年时并非如此。然而，这种差异主要由住院期间较高的非Q波MI发生率驱动；采用更现代的SCAI对MI的定义，短病变（<25毫米）组与长病变（≥25 - 40毫米）组的MI发生率无显著差异。
