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Updated: Aug 16, 2025
In Vivo Quantitative Assessment of Myocardial Structure, Function, Perfusion and Viability Using Cardiac Micro-computed Tomography
Published on: February 16, 2016
Myocardial Perfusion and Coronary Physiology Assessment of Microvascular Dysfunction in Patients Undergoing
M M Dobrolinska1, P Gąsior1, A Błach1,2
1Department of Cardiology and Structural Heart Diseases, Medical University of Silesia in Katowice, 40-635 Katowice, Poland.
Insights
This study evaluates coronary artery disease (CAD) assessment in severe aortic stenosis (AS) patients undergoing TAVI. It compares invasive indices like FFR with CZT-SPECT to define significant stenosis, aiding treatment decisions.
Area of Science:
- Cardiology
- Interventional Cardiology
- Cardiac Imaging
Background:
- Coronary artery disease (CAD) affects 30-68% of severe aortic stenosis (AS) patients.
- Invasive assessment of CAD severity (e.g., fractional flow reserve - FFR) in AS is debated due to hemodynamic influences.
- Transcatheter aortic valve implantation (TAVI) is a common treatment for severe AS.
Purpose of the Study:
- To assess acute and long-term changes in FFR, index of microvascular resistance (IMR), and coronary flow reserve (CFR) post-TAVI.
- To compare the diagnostic accuracy of these intracoronary indices against myocardial perfusion measured by CZT-SPECT.
- To establish cut-off values for FFR, IMR, and CFR that indicate significant coronary stenosis in the LAD artery.
Main Methods:
- Enrollment of 40 TAVI-eligible patients with intermediate (30-70%) left anterior descending (LAD) stenosis.
- Measurement of FFR, CFR, and IMR before and after TAVI (acute and 6-month follow-up).
- Simultaneous myocardial blood flow assessment using CZT-SPECT, correlated with intracoronary measurements.
Main Results:
- The study aims to quantify hemodynamic and microvascular changes after TAVI.
- It seeks to validate intracoronary indices against CZT-SPECT myocardial perfusion.
- Establishing reliable cut-off values for diagnosing significant stenosis is a key outcome.
Conclusions:
- This research will clarify the utility of invasive CAD assessment in AS patients undergoing TAVI.
- Findings will help optimize diagnostic strategies for coronary stenosis in this population.
- The study aims to improve treatment decisions by providing accurate stenosis severity indicators.
Abstract:
The prevalence of coronary artery disease (CAD) in patients with severe aortic stenosis (AS) is 30-68%. Nevertheless, there is still not enough evidence to use invasive assessment of lesion severity, because the hemodynamic milieu of AS may impact the fractional flow reserve (FFR) and non-hyperemic indices. Therefore, the aim of the study is two-fold. First, to measure acute and long-term changes of FFR, index of microvascular resistance (IMR), and coronary flow reserve (CFR) in patients undergoing TAVI procedure. Second, to compare the diagnostic accuracy of intracoronary indices with myocardial perfusion measured by cadmium-zinc-telluride single-photon emission tomography (CZT-SPECT) and find cut-off values defining significant stenosis. We plan to enroll 40 patients eligible for TAVI with intermediate stenosis (30-70%) in the left anterior descending (LAD) coronary artery. In each patient FFR, CFR, and IMR will be measured in addition to myocardial blood flow calculated by CZT-SPECT before and either immediately after TAVI (acute cohort) or in 6 months (late cohort) after the procedure. FFR, CFR, and IMR will be matched with the results of myocardial perfusion measured by CZT-SPECT in the area of LAD. As a result, cut-off values of FFR, CFR, and IMR defining the decreased blood flow will be found.
