Coronary artery disease is a leading cause of death and disability worldwide. Invasive coronary angiography (ICA) is considered a standard for determining the percent of stenosis, or narrowing, due to plaque in a coronary artery. However, the degree of stenosis on ICA is not always an accurate predictor of heart attack risk because it gives no information on perfusion, or the flow of blood into the heart muscle. Inadequate perfusion, also known as ischemia, is a potential danger to the patient.
In contrast to invasive coronary angiography, cardiac hybrid imaging is a viable option, which is known to be highly effective than ICA. Cardiac hybrid imaging combines coronary computed tomography angiography (CCTA) and myocardial perfusion imaging with single photon emission tomography (SPECT) to provide information on both stenosis and perfusion. As of recent times, its high efficiency is said to exist in terms of promising results shown on short-time observations. However, further research and associated innovations are expected to bring in positive results on a long-term basis too.
A recent hybrid imaging conducted on 428 patients showed up 160 cases affected with adverse cardiac events, after a median follow-up of 6.8 years. This also includes 45 deaths that were observed in the final study population. According to Dr. Philipp A. Kaufmann, coauthor of the study, professor and chair of nuclear medicine, and director of cardiac imaging at University Hospital Zurich in Switzerland, cardiac hybrid imaging can help guiding treatment decisions, and is an excellent long-term predictor of adverse cardiac events in patients evaluated for coronary artery disease.
The researchers hope to run a trial to show that hybrid imaging can have a positive impact on patient outcomes. They are also looking at what they call “triple hybrid” imaging, which combines the CCTA/SPECT hybrid with information on coronary artery shear stress. The shear stress information could help identify lesions that do not yet have an impact on ischemia but will in the future.