The primary objective of this study is to determine whether a reduced radiation protocol (RRP) in which angiograms are acquired at ultralow radiation doses and then processed using spatiotemporal enhancement software can produce similar quality angiographic images as compared with standard techniques.

Coronary angiography is an essential diagnostic tool for determining the presence and severity of coronary artery disease, a leading cause of morbidity and mortality worldwide. While the basic techniques of coronary angiography have remained unchanged, the field of medical imaging has undergone significant advancements in hardware and software, offering new possibilities for enhanced visualization of the coronary arteries, better diagnostic accuracy, and improved patient and staff safety. However, the use of radiation during coronary angiography, which is necessary for image acquisition, exposes patients, physicians, and staff to potential risks, including radiation-induced tissue damage and an increased long-term risk of cancer. While the risks to patients attributable to the relatively low radiation doses they receive during single catheterization procedures are minimal, the cumulative risks of occupational radiation exposure are higher among physicians and staff, who are repetitively exposed to scattered radiation on a daily basis and accumulated over the course of years working in the catheterization laboratory. This occupational radiation exposure has been associated with an increased risk of cataracts, premature atherosclerosis, and certain cancers among physicians and staff. There is therefore a pressing need to explore strategies to minimize radiation doses used during coronary angiography without compromising the diagnostic accuracy of coronary artery disease detection.

Recent advancements in computational power and image processing algorithms provide opportunities for substantial reductions in radiation doses used during coronary angiography. One such advancement is spatiotemporal enhancement processing (STEP) which improves the signal to noise ratio of time sequenced angiographic data and enhances the visibility of vascular structure. This innovative STEP technique has the promise of minimizing patient and operator radiation exposure while maintaining adequate image quality. The purpose of this pilot study is to investigate a novel strategy of radiation dose reduction and data processing in coronary angiography. This pilot study will be performed in patients undergoing clinically-indicated diagnostic coronary angiography.

The study will compare angiograms acquired at ultralow radiation doses and processed with spatiotemporal enhancement software (STEP-angiograms) to standard of care angiograms (SOC-angiograms) acquired with normal radiation dose settings and no additional processing. The objectives are to assess offline whether the low radiation STEP-angiograms are of equivalent diagnostic quality as SOC-angiograms. In future research studies, the STEP software will be tested in the clinical setting to evaluate how the software may improve patient safety, enhance the overall quality of care, promote the responsible use of radiation in coronary angiography procedures, and reduce occupational radiation doses among physician and staff in the catheterization laboratory.

Inclusion Criteria:

• Referred for clinically indicated coronary angiography
• ≥18 years of age
• Not pregnant
• English speaking
• Not imprisoned
• Able to provide written informed consent

Exclusion Criteria:

• Hemodynamically or electrically unstable.
• Indication for coronary angiography is emergent, including ST-segment elevation myocardial infarction
• History of coronary artery bypass grafting
• An eGFR <60
• Pregnant or lactating
• A BMI of 45 or greater
• Any other factor that the investigator feels would put the patient at increased risk or otherwise make the patient unsuitable for participation in the protocol.

Patients suspected to have coronary artery disease (CAD) who are undergoing diagnostic coronary angiography with or without possible percutaneous coronary intervention (PCI).

Within 12 months