Brad J. Martinsen

Orbital atherectomy for treating de novo, severely calcified coronary lesions: 3-year results of the pivotal ORBIT II trial

BACKGROUND/PURPOSE The presence of heavy coronary artery calcification increases the complexity of percutaneous coronary intervention (PCI) and increases the incidence of major adverse cardiac events (MACE): death, myocardial infarction (MI), target vessel revascularization (TVR), and stent thrombosis. The ORBIT II (Evaluate the Safety and Efficacy of OAS in Treating Severely Calcified Coronary Lesions) trial reported low rates of procedural, 30-day, 1-year, and 2-year ischemic complications after treatment of de novo, severely calcified lesions with the Diamondback 360° Coronary Orbital Atherectomy System (OAS) (Cardiovascular Systems, Inc.). METHODS/MATERIALS ORBIT II was a single-arm trial that enrolled 443 patients at 49U.S. sites; in this study, de novo, severely calcified coronary lesions were treated with OAS prior to stenting. The primary safety endpoint was 30-day MACE: the composite of cardiac death, MI, and TVR (inclusive of target lesion revascularization (TLR)). The primary efficacy endpoint was procedural success: stent delivery with a residual stenosis of <50% without the occurrence of in-hospital MACE.The present analysis reports the final, 3-year follow-up results from ORBIT II. RESULTS The majority of subjects (88.2%) underwent PCI with drug-eluting stents after orbital atherectomy. There were 360 (81.3%) subjects who completed the protocol-mandated 3-year visit.The overall cumulative rate of 3-year MACE was 23.5%, including cardiac death (6.7%), MI (11.2%), and TVR (10.2%). The 3-year target lesion revascularization rate was 7.8%. CONCLUSIONS In the final 3-year analysis of the ORBIT II trial, orbital atherectomy of severely calcified coronary lesions followed by stenting resulted in a low rate of adverse ischemic events compared with historical controls.Orbital atherectomy represents a safe and effective revascularization strategy for patients with severely calcified coronary lesions. SUMMARY The ORBIT II trial enrolled 443 subjects to study orbital atherectomy followed by stenting for de novo severely calcified coronary lesions. The overall cumulative 3-year MACE rate was 23.5%, including cardiac death (6.7%), MI (11.2%), and TVR (10.2%); the 3-year target lesion revascularization rate was 7.8%. Orbital atherectomy of heavily calcified coronary lesions followed by stenting results in a low rate of adverse ischemic events compared with historical controls; it represents a reasonable revascularization strategy for patients with severely calcified coronary lesions.

Orbital atherectomy for the treatment of severely calcified coronary lesions: evidence, technique, and best practices

ABSTRACT Introduction: The presence of severe coronary artery calcification is associated with higher rates of angiographic complications during percutaneous coronary intervention (PCI), as well as higher major adverse cardiac events compared with non-calcified lesions. Incorporating orbital atherectomy (OAS) for effective preparation of severely calcified lesions can help maximize the benefits of PCI by attaining maximal luminal gain (or stent expansion) and improve long-term outcomes (by reducing need for revascularization). Areas covered: In this manuscript, the prevalence, risk factors, and impact of coronary artery calcification on PCI are reviewed. Based on current data and experience, the authors review orbital atherectomy technique and best practices to optimize lesion preparation. Expert Commentary: The coronary OAS is the only device approved for use in the U.S. as a treatment for de novo, severely calcified coronary lesions to facilitate stent delivery. Advantages of the device include its ease of use and a mechanism of action that treats bi-directionally, allowing for continuous blood flow during treatment, minimizing heat damage, slow flow, and subsequent need for revascularization. The OAS technique tips reviewed in this article will help inform interventional cardiologists treating patients with severely calcified lesions.

Atherectomy Devices for the Treatment of Calcified Coronary Lesions

The presence of moderate and severe coronary artery calcification (CAC) is associated with higher rates of angiographic complications during percutaneous coronary intervention (PCI), as well as higher major adverse cardiac events compared with noncalcified lesions. Diabetes mellitus, a risk factor for CAC, is increasing in the United States. Vessel preparation before PCI with atherectomy can facilitate successful stent delivery and expansion that may otherwise not be possible. We review here CAC prevalence, risk factors, and impact on PCI, as well as the currently available coronary atherectomy devices including rotational atherectomy, orbital atherectomy, and laser atherectomy.

Orbital atherectomy treatment of severely calcified coronary lesions in patients with impaired left ventricular ejection fraction: one-year outcomes from the ORBIT II study

AIMS Percutaneous coronary intervention (PCI) of severe coronary artery calcification (CAC) is challenging. The ORBIT II study demonstrated the safety and efficacy of orbital atherectomy (OA) in patients with severe CAC. Microparticulate liberated during OA may disturb the coronary microcirculation. In the present study, we evaluated OA treatment in patients with left ventricular systolic dysfunction. METHODS AND RESULTS Patients were grouped by left ventricular ejection fraction (LVEF): 26-40% (n=33), 41-50% (n=90), and >50% (n=314). Procedural success was similar (LVEF 26-40%: 90.9%, LVEF 41-50%: 88.9%, LVEF >50%: 88.4%). Rates of major adverse cardiac events (MACE), defined as cardiac death, myocardial infarction, and target vessel revascularisation, were similar in the LVEF 26-40%, 41-50%, and >50% groups, respectively, at 30 days (9.1%, 7.8%, 11.5%) and one year (18.2%, 19.1%, 16.0%). Although the 30-day cardiac death rate was 0% in patients with left ventricular dysfunction, one-year cardiac death was higher compared with patients with preserved left ventricular systolic function. CONCLUSIONS No patient with left ventricular systolic dysfunction experienced cardiac death at 30 days suggesting that OA was well tolerated without haemodynamic complication. However, one-year cardiac death was higher in patients with left ventricular systolic dysfunction, consistent with previous studies demonstrating the association between reduced left ventricular function and increased mortality after PCI.

Impact of diabetes mellitus on procedural and one year clinical outcomes following treatment of severely calcified coronary lesions with the orbital atherectomy system: A subanalysis of the ORBIT II study

The goal of the study was to investigate the safety and efficacy of the coronary orbital atherectomy system to treat severe coronary artery calcification (CAC) prior to stent placement in diabetic and non‐diabetic patients.

Utilizing intravascular ultrasound imaging prior to treatment of severely calcified coronary lesions with orbital atherectomy: An ORBIT II sub‐analysis

OBJECTIVES We sought to assess the clinical outcomes when intravascular ultrasound (IVUS) was used prior to orbital atherectomy treatment (OA) versus angiography alone for lesion assessment. BACKGROUND Percutaneous coronary intervention (PCI) of severely calcified lesions is associated with high rates of major adverse cardiac events (MACE). IVUS provides additional diagnostic information to optimize PCI. METHODS ORBIT II was a single-arm study of 443 patients with de novo, severely calcified coronary lesions treated with OA before stent placement. Patients with IVUS imaging prior to OA (N = 35) were compared to patients without IVUS imaging for initial lesion assessment (N = 405). In this post-hoc sub-analysis procedural outcomes and the 3-year MACE rate were evaluated. RESULTS The rates of severe angiographic complications were low in patients with and without IVUS imaging prior to OA. There was a significant reduction in the number of stents used in patients with IVUS imaging prior to OA (1.0 ± 0.2 vs 1.3 ± 0.6; P = 0.006) and increased post-OA mean minimal lumen diameter (MLD) (1.6 ± 0.6 mm vs 1.2 ± 0.5 mm; P < 0.001). The 3-year MACE rate was similar in both groups (IVUS: 14.3% vs No IVUS: 24.2%; P = 0.26). CONCLUSIONS There were significantly fewer stents placed, increased post-OA MLD, and similar 3-year MACE outcomes in patients with IVUS assessment of the degree of lesion calcification prior to OA as compared to patients with angiographic assessment of the degree of lesion calcification. Further studies are needed to determine the optimal integration of intravascular imaging with OA.

ORBIT II sub-analysis: Impact of impaired renal function following treatment of severely calcified coronary lesions with the Orbital Atherectomy System.

To investigate the safety and efficacy of the coronary Orbital Atherectomy System (OAS) to prepare severely calcified lesions for stent deployment in patients grouped by renal function.

Acute procedural outcomes of orbital atherectomy for the treatment of iliac artery disease: Sub-analysis of the CONFIRM registries

Endovascular intervention is an appealing revascularization strategy for iliac artery disease. Atherectomy of the iliac artery is uncommon due to the risk of life-threatening perforation but may be necessary if the iliac lesion is heavily calcified, preventing stent delivery or optimal expansion. We assessed the feasibility and safety of orbital atherectomy for the treatment of iliac artery disease. Demographic data, lesion characteristics, and procedure outcomes for the CONFIRM patients with at least one iliac artery lesion treated with orbital atherectomy (n=62 patients; n=68 lesions) were compared to patients with at least one superficial femoral artery (SFA) lesion treated with orbital atherectomy (n=1570 patients; n=1809 lesions). The procedural complication rate, defined as the composite of flow limiting dissection, perforation, slow flow, vessel closure, spasm, embolism, or thrombosis, was compared in iliac lesions versus SFA lesions. The iliac artery group had more patients with diabetes, shorter lesions, and more severely calcified lesions. The orbital atherectomy run time was significantly shorter in the iliac artery group. Additionally, in the iliac group there was one reported perforation and one reported vessel closure; the rates of slow flow, spasm, embolism, thrombus, and flow limiting dissection were 0%. The overall procedural complication rate was significantly lower in the iliac group (2.9% vs. 11.2%, p=0.03). Orbital atherectomy of the iliac artery is feasible with few reported angiographic complications and compared favorably with the SFA group. Orbital atherectomy may be considered to facilitate the delivery and expansion of a balloon or stent if the iliac artery is calcified.

Critical hand ischemia treatment via orbital atherectomy—A single center observational retrospective analysis

BACKGROUND/PURPOSE Critical hand ischemia (CHI) can be devastating and may result in amputation. Distal vessel calcification has been shown to be a major factor in causing CHI. Atherectomy in the upper extremities is not typically considered due to the small anatomy; however, the Diamondback 360° Peripheral Orbital Atherectomy System (OAS) (Cardiovascular Systems, Inc.) can access treatment areas with a reference vessel diameter of 1.5mm. METHODS/MATERIALS A retrospective, observational, single center (Merit Health Center, Jackson, MS) analysis of 11 CHI patients with calcific disease of the radial artery treated with orbital atherectomy (OAS) was completed. Demographics and procedural to 30-day outcomes were assessed. RESULTS All patients had good blood flow to the hand after intervention and none experienced complications during or immediately post-procedure. At 30-days the freedom from revascularization and amputation was 100%, and all the wounds were healed. The following important principles were followed during the use of OAS for CHI: (1) ACT was therapeutic (~250s); (2) Gentle wire manipulation; (3) Utilization of a small OAS crown (1.25mm); (4) Aggressive vasodilator use-given through the exchange catheter; (5) Angioplasty balloon was matched to the size of the vessel and long and low pressure inflations were completed. CONCLUSIONS Critical hand ischemia can be treated with endovascular techniques. Obtaining good outflow to the fingers is critical for wound healing and preventing amputation. Orbital atherectomy is a useful tool in preparing vessels for balloon angioplasty; particularly in cases where calcification is present.

INCIDENCE OF TEMPORARY TRANSVENOUS PACEMAKER PLACEMENT WITH CORONARY ORBITAL ATHERECTOMY COMPARED TO ROTATIONAL ATHERECTOMY

Transvenous temporary pacing (TVP) is often used during percutaneous coronary intervention (PCI) in patients undergoing rotational atherectomy (RA) and is recommended for prophylactic use in all cases involving the RCA. The placement of transvenous pacing has cost implications, but more importantly