Prospective, Multicenter, Observational Study to Evaluate Clinical Outcomes of Orbital Atherectomy in Severely Calcified Coronary Arteries Under OCT Guidance

Coronary artery disease (CAD) remains a major contributor to cardiovascular morbidity and mortality worldwide, forming a substantial portion of the global burden of cardiovascular diseases (CVD).In 2019, CVDs accounted for 33% of all global deaths, with ischemic heart disease and stroke being major contributors.In India, the prevalence of CAD is estimated at 10.5%, exceeding the global average and indicating a higher disease burden.

Initially thought to be a passive degenerative process, coronary artery calcification (CAC) is commonly indicative of advanced atherosclerosis. CAC is associated with decreased vascular compliance and increases the risk for adverse cardiovascular events. It is an age-related condition that typically begins to manifest after the age of 40 and is most prevalent in men over the age of 70.  Risk factors such as diabetes, chronic kidney disease, hypertension, hyperlipidemia, and smoking have all been shown to accelerate the development of calcified lesions in the coronary arteries. These calcified plaques pose a significant challenge during percutaneous coronary intervention (PCI), often complicating stent delivery and expansion. In Indian patients, studies have reported moderate to severe calcification in 11.6% to 17% of coronary lesions, with nearly 80% falling under type B or type C classification, underscoring the need for effective lesion preparation strategies.

Despite technological advancements in interventional cardiology, treating heavily calcified lesions remains complex. One promising approach is orbital atherectomy (OA), a technique that modifies and debulks calcified plaques to facilitate successful stent deployment. Approved by the US FDA in 2013, OA has been increasingly adopted for this purpose and is currently recommended by the 2021 ACC/AHA/SCAI guidelines for managing heavily calcified lesions during PCI.

Intravascular imaging has become an invaluable intraprocedural tool in guiding PCI procedures, enabling detailed assessment of extent, phenotype, and location of calcium in target coronary arteries, enhancing optimal stent deployment and reducing adverse events.

Optical Coherence Tomography (OCT)is a high-resolution intravascular imaging modality that provides detailed visualization of coronary artery structures, making it particularly valuable in the assessment and management of complex, calcified, and tortuous lesions. OCT enables precise evaluation of calcium characteristics—such as thickness, arc, and length—as well as the degree of ablation within the intima and media. This level of detail aids in optimal lesion preparation, contributing to improved procedural outcomes.

Given the rising complexity of severely calcified lesions and the need for improved procedural outcomes, exploring the use of OA under OCT guidance could offer valuable insights into optimizing treatment for these challenging cases. Combining OA with OCT could enhance lesion preparation, improve stent deployment, and increase procedural success rates.

This study aims to assess the clinical outcomes of OA performed under OCT guidance for the treatment of severely calcified coronary artery lesions over a one-year period.