Orbital atherectomy system in treating calcified coronary lesions: 3-Year follow-up in first human use study (ORBIT I trial)

Background/Purpose: The ORBIT I trial evaluated the safety and performance of an orbital atherectomy system (OAS) in treating de novo calcified coronary lesions. Severely calcified coronary arteries pose ongoing treatment challenges. Stent placement in calcified lesions can result in stent under expansion, malapposition and procedural complications. OAS treatment may be recommended to facilitate coronary stent implantation in these difficult lesions. Materials/Methods: Fifty patients with de novo calcified coronary lesions were enrolled in the ORBIT I trial. Patients were treated with the OAS followed by stent placement. Our institution treated 33/50 patients and continued follow-up for 3. years. Results: Average age was 54.4. years and 90.9% were males. Mean lesion length was 15.9. mm. The average number of OAS devices used per patient was 1.3. Procedural success was achieved in 97% of patients. Angiographic complications were observed in five patients (two minor dissections, one major dissection and two perforations). The cumulative major adverse cardiac event (MACE) rate was 6.1% in-hospital, 9.1% at 30. days, 12.1% at 6. months, 15.2% at 2. years, and 18.2% at 3. years. The MACE rate included two in-hospital non Q-wave myocardial infarctions (MI), one additional non Q-wave MI at 30. days leading to target lesion revascularization (TLR), and three cardiac deaths. Conclusions: The ORBIT I trial suggests that OAS treatment may offer an effective method to modify calcified coronary lesion compliance to facilitate optimal stent placement in these difficult-to-treat patients with acceptable levels of safety up to 3. years post-index procedure.