angiography based simulation of FFR

• Applicant: Dr. Fabian Ammon
• Subject Area: Cardiology, Angiology
• Term: from 2021 to 2023
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 468039736

Atherosclerosis of the coronary arteries is one of the leading causes of morbidity and mortality in the Western world. The clinical presentation ranges from stable angina on exertion to myocardial infarction and sudden cardiac death. Outside of acute coronary syndrome, evidence of myocardial ischemia is generally required to establish the indication for revascularization of coronary stenosis. Various stress tests or examinations are used for this purpose. However, despite this recommendation, more than 40% of coronary angiographies are performed in stable patients without prior noninvasive evidence of ischemia. In the absence of noninvasive evidence of ischemia or if the association between ischemia and coronary stenosis is not clear, invasive coronary angiography offers the possibility to determine the "fractional flow reserve" (FFR) to obtain information about the hemodynamic relevance of coronary stenoses. In this method, an extremely thin wire carrying a pressure sensor at its tip is inserted into the coronary artery during coronary angiography and the blood pressure upstream and downstream of a coronary stenosis is compared after vascular dilatation has been achieved pharmacologically, usually with adenosine. If the quotient of poststenotic to prestenotic blood pressure is ≤0.8, hemodynamic relevance is present and patients benefit from revascularization.Based on the convincing evidence from studies, FFR measurement is listed as a class IA recommendation by the European Society of Cardiology for assessing the need for treatment of coronary stenosis.For several years, there have been scientific efforts to obtain information regarding the hemodynamic relevance of possible stenoses from invasive coronary angiography, which solely depicts the anatomy of the vessel lumen. Using different methodological approaches, several studies showed that fractional flow reserve can be simulated or calculated based on invasive coronary angiography.The purpose of this project is to scientifically evaluate angiography-based fractional flow reserve (FFRangio) simulation in order to contribute to the clinical validation of the method, to identify factors influencing diagnostic validity, and to enable further development of the method. New methods such as the FFRangio presented here must lead to robust results in order to be widely used in clinical practice. Therefore, the influence of the following parameters on the outcome of FFRangio and the correlation of FFRangio to established invasive FFR will be systematically evaluated:1. influence of cardiac phase2. influence of the frame rate 3. influence of stenosis localization4. inter-operator variability5. comparison of FFRangio with simulation of FFR from coronary CT angiography datasets.6. comparison of FFRangio with other invasive parameters for estimating the severity of coronary stenosis such as pd/pa, iFR, RFR.

• DFG Programme: Research Grants
• Co-Investigator: Privatdozent Dr. Mohamed Marwan