Clinical Trials Logo

Clinical Trial Summary

This purpose of this research project is to test the diagnostic accuracy (i.e., sensitivity, specificity, positive and negative predictive value, and receiver operator curve area under the curve) of cardiac computed tomography (CT) perfusion as compared to the best non-invasive test of blood flow -- cardiac positron emission transmission (PET) perfusion imaging.

The primary outcome of the study is to determine the CT perfusion technique with the highest overall diagnostic accuracy measured by the highest area under the receiver operator curve.

The investigators will test 4 different CT perfusion techniques. (A) Qualitative, visual inspection of the contrast-enhanced CT images (B) Enhanced voxel distribution analysis (C) Rate of myocardial contrast enhancement analysis (D) Quantitative heart blood flow using a distributed 2-region analysis

A second aim is to reduce the radiation dose needed to maintain CT perfusion diagnostic accuracy. Using the CT perfusion data, the investigators will model the minimal number of cardiac cycle radiation exposures needed to keep the diagnostic accuracy similar to the full data set.

A third aim is to test the incremental diagnostic accuracy of CT angiography plus CT perfusion to identify regions of low blood flow as compared to PET perfusion alone.

Clinical Trial Description

Chest pain and other symptoms can occur as a result of blockages in the arteries that supply the heart; these arteries are called the "coronary arteries". Blockages in the coronary arteries may decrease blood flow and oxygen delivery to the heart muscle, causing chest pain or other "anginal" symptoms. Coronary angiography is a commonly used test to visualize coronary artery disease or blockages but may not provide all the answers physicians need to assess patients with symptoms like chest pain. Two options for coronary angiography exist, invasive angiography and cardiac computed tomography angiography (CCTA). CCTA is completed by injecting contrast into a peripheral vein (not an artery) and then imaging when the coronary arteries fill with contrast. The imaged coronary arteries may be blocked partially, completely or not at all. While a blockage that occludes greater than 70% of an artery is highly correlated with chest pain or other anginal symptoms, occlusions of 40% or more may or may not decrease heart blood flow. Often multiple imaging studies are needed to evaluate whether blood flow is decreased in the setting of partial coronary artery blockages including non-invasive heart imaging to assess heart blood flow.

One type of nuclear imaging is termed positron emission tomography (PET). In order to differentiate blockages that have poor heart perfusion with activity, nuclear PET images are taken at rest, when flow should be normal, and then repeated after the investigators "stress" the heart with medications. If blood flow is decreased during stress, a "defect" on the PET images is seen.

An alternative, non-invasive technique to test for heart blood flow/perfusion to to measure heart blood flow as computed tomography (CT) contrast goes in and comes out. Preliminary studies in animals and humans to assess heart blood flow/perfusion using contrast-enhanced cardiac CT have been promising, but further work is needed. Combining CCTA with CT blood flow/perfusion measurements in the same setting could lead to a single, accurate diagnostic test that measures coronary artery blockage as well as blood flow.

One limitation of CT imaging is the amount of radiation that can be given. The CCTA radiation dose is currently less than both nuclear PET imaging and invasive coronary angiography. However, if CT blood flow imaging is added to routine CCTA to assess heart perfusion and coronary blockages in one test, the radiation dose may be higher.

The primary purpose of this research project is to test the diagnostic accuracy of various cardiac CT perfusion techniques as compared to the best non-invasive test of blood flow, cardiac PET perfusion imaging. The investigators goal is to use the least amount of radiation to achieve a high diagnostic accuracy for CCTA as well as CT blood flow/perfusion. The investigators goal is to have CT heart blood flow/perfusion radiation doses that are the same or less than nuclear blood flow imaging. The investigators have estimated that they need as few as 4 low radiation dose images of the heart to allow accurate heart blood flow measurement. ;

Study Design

Related Conditions & MeSH terms

NCT number NCT01434043
Study type Observational
Source University of Washington
Status Active, not recruiting
Start date September 2011
Completion date December 31, 2019

See also
  Status Clinical Trial Phase
Recruiting NCT03810599 - Patient-reported Outcomes in the Bergen Early Cardiac Rehabilitation Study N/A
Completed NCT02528474 - Comparison of Optical Coherence Tomographic Findings After Balloon Angioplasty With Two Different Paclitaxel-Coated Balloons for the Treatment of In-Stent Restenosis in Drug-Eluting Stents N/A
Recruiting NCT03471234 - Latin America Real World Study With Inspiron Drug Eluting Stent - INSPIRON LATITUDE
Completed NCT02115308 - Characterization of Changes in Ventricular Mechanics in Response to Lexiscan Stress Using Tagged Cine Cardiac Magnetic Resonance Imaging Phase 4
Terminated NCT01374555 - Evaluation of the CardioSond Electronic Stethoscope in the Detection of Coronary Artery Disease
Active, not recruiting NCT03216720 - Miniaturized Extracorporeal Circulation Study N/A
Completed NCT03226262 - FFRangio Accuracy vs. Standard FFR
Recruiting NCT03622671 - Fibrin Clot Properties and Blood Loss Following Coronary Artery By-pass Grafting N/A
Recruiting NCT03378934 - Anti-platelet Effect of Berberine in Patients After Elective Percutaneous Coronary Intervention Phase 4
Recruiting NCT03707626 - Collateral Circulation to LAD and Wellens Sign
Completed NCT01930214 - Multi-center Prospective Study to Evaluate Outcomes of the Moderate to Severely Calcified Coronary Lesions (MACE) N/A
Recruiting NCT03709836 - Computed Tomography Angiography Prediction Score for Side Branch Occlusion
Completed NCT02272582 - A Study to Evaluate the Use of SOMVC001 (GALA) Vascular Conduit Preservation Solution in Patients Undergoing CABG (STEPS) N/A
Recruiting NCT03265535 - Validation of a Single Rest-Stress Imaging Protocol for Myocardial Perfusion Imaging N/A
Not yet recruiting NCT03265041 - Long Term Predictors of Graft Patency After Coronary Artery Bypass Graft Surgery (Multi-slice CT Coronary Angiography Study Validated by Coronary Angiography)
Not yet recruiting NCT03646019 - Serum Oxidative Status as a Potential Predictor of Coronary Artery Disease.
Recruiting NCT03518437 - Coronary Atherosclerosis Disease Early Identification and Risk Stratification by Noninvasive Imaging
Recruiting NCT02832115 - Topical Nitroglycerine Treatment for Radial Artery Spasm Prevention Phase 4
Recruiting NCT02939729 - Physiotherapy Prehabilitation in Patients Undergoing Cardiac or Thoracic Surgery N/A
Recruiting NCT03027856 - The BIFSORB Pilot Study II N/A