Orbital Atherectomy

Orbital atherectomy (OA) is an adjunctive therapy used for lesion preparation of calcified plaque before percutaneous coronary intervention (PCI) and peripheral percutaneous endovascular interventions. The goal of lesion preparation with OA is to modify calcified plaque, which changes the lesion compliance and allows for the adequate balloon and stent expansion in segments with heavily calcified lesions. Coronary artery disease (CAD) has a significant impact on overall health and continues to grow in prevalence in the United States. Data from the American Heart Association states that greater than 15.5 million people over age 20 have significant CAD. The deaths due to cardiovascular disease have also steadily increased since 1990 , with nearly 650,000 deaths due to cardiovascular disease in 2019. In patients with advanced CAD, coronary artery calcification (CAC) is associated with increased atherosclerosis and potential future cardiac events.  CAC is believed to be both gender and age-dependent. The prevalence of CAC in individuals over age 70 has been estimated to be greater than 90% in men and 67% in women. CAC is better detected using intravascular ultrasound (IVUS) or optical coherence tomography (OCT) compared to coronary angiography. A previous study in patients with known CAD demonstrated that coronary angiography could detect coronary calcium in 38% of lesions versus 73% utilizing IVUS. As intravascular imaging modalities are underutilized, CAC is likely underestimated in the general population. As CAD prevalence increases, the incidence of CAC follows a similar trend. Previous studies have shown that those patients with severe CAC have more complex and worse outcomes when undergoing percutaneous intervention (PCI) than patients with low CAC. The importance of recognizing CAC is rooted in previous studies demonstrating technically more challenging cases of PCI, as well as worse outcomes. Two different meta-analyses have revealed that severe coronary calcium is associated with less complete revascularization, increased mortality, increased rate of myocardial infarction (MI), and increased rate of coronary revascularization. The noted worse outcomes in patients with severe coronary calcium are multifactorial but are likely strongly associated with poor balloon expansion resulting in incomplete stent expansion and coronary calcium damaging stent polymer coating, decreasing efficacy.  To help decrease complication rates and improve stent deployment in patients with severe CAC, utilization of OA can be of significant benefit for vessel preparation and stent placement. In this manuscript, we provide a review of OA and the available devices, techniques, indications, complications, contraindications, and clinical trial outcomes based on the most recent data.