Clinical Impact of Cardiac Photon-Counting Detector CT

This study will focus on demonstrating the benefits of PCD-CT for clinical indications and findings where the improved spatial and temporal resolution, decreased quantum and electronic noise, improved spectral imaging capabilities, and increased iodine signal are expected to benefit the diagnosis and characterization of CAD and myocardial perfusion defects.

Inclusion criteria

• Patients referred for coronary artery cardiac CT imaging or nuclear medicine or MRI cardiac perfusion within the Department of Radiology or Cardiology.
• Patients who are able and willing to sign the informed consent will be enrolled
• Negative pregnancy test if subject is of child-bearing age (females of child-bearing potential will be screened for pregnancy using a urine pregnancy test, which will be administered by the unit study coordinator at no cost to the patient).

Exclusion criteria

• Patients unable to provide written informed consent
• Pregnancy
• eGFR ≤ 30
• History of prior moderate or severe contrast reaction includes: unresponsiveness, severe respiratory distress, convulsions, arrhythmia, cardiopulmonary distress, progressive angioedema, laryngeal edema, dyspnea, bronchospasm, symptomatic tachycardia, symptomatic bradycardia, hypotension, hypertensive crisis.
• Any history of required premedication prior to iodinated contrast administration.
• Patients that consent to participation but do not undergo their clinically-indicated, contrast-enhanced CT, or nuclear medicine or MR perfusion scanning for any reason (e.g., bad IV, infiltration, reaction, change in indication).
• Patients experiencing atrial fibrillation, premature ventricular contractions or other heart rhythm abnormalities
• Hospitalized patients or patients under care in the Emergency Department

Specific exclusion criteria only for participation in the cardiac stress test arm of this study (requiring administration of Regadenoson):

• Anything by mouth within three hours of the examination
• Known hypersensitivity to Regadenoson, Adenosine, or Dipyridamole.
• Active ongoing wheezing or poorly controlled asthma or COPD (hospitalized within last month or receiving treatment for flair within last month).
• Second (type I or II) or third degree atrioventricular (AV) block or sinus node dysfunction unless patient has functioning artificial pacemaker.
• Ingested greater than 4 oz. of caffeine within the last 12 hours.
• Currently experiencing unstable coronary syndrome.
• Uncontrollable seizures within the last 3 months