Clinical validation of intravascular physiology and imaging modalities for the assessment of intermediate stenosis in the left main coronary artery

• Grant number: 19/10697-5
• Support Opportunities: Regular Research Grants
• Start date: March 01, 2020
• End date: August 31, 2022
• Field of knowledge: Health Sciences - Medicine
• Principal Investigator: Fausto Feres
• Grantee: Fausto Feres
• Host Institution: Instituto Dante Pazzanese de Cardiologia (IDPC). Fundação Adib Jatene (FAJ). Secretaria da Saúde (São Paulo - Estado). São Paulo , SP, Brazil
• Associated researchers: Daniel Silva Chamie de Queiroz ; José de Ribamar Costa Júnior

Abstract

Accurate determination of the functional significance of intermediate lesions located in the left main coronary artery (LMCA) are critical for decisions about the need of coronary revascularization. Stenoses in downstream vessels (left anterior descending and/or left circumflex arteries) - which frequently coexist with stenosis in the LMCA - significantly influence the fractional flow reserve (FFR) assessment of LMCA stenosis. More recently introduced to clinical practice, the instantaneous wave-free ratio (iFR) is less influenced by serial stenosis, and in theory, could be more accurate for assessment for LMCA stenoses. However, iFR has not been validated to investigate the physiological significance of LMCA lesions. Due to the possibility of characterizing the atheroma components and accurately determining coronary stenosis severity, intravascular imaging modalities have become very attractive for invasive assessment of coronary lesions, but poorly validated for assessment of LMCA stenoses. The main objective of the current research project is to determine the impact of stenoses in downstream vessels on FFR and iFR measurements of LMCA stenoses. The primary endpoint is the change in FFR and iFR values prior and after percutaneous treatment of downstream stenoses. Assuming a change of 0.04 mmHg between the FFRpredicted and FFRtrue with a standard deviation of 0.04 mmHg, and a change of 0.01 mmHg between iFRpredicted and iFRtrue with a standard deviation of 0.03 mmHg, a total of 53 patients are needed t oconfirm the mean difference of 0.03 mmHg between iFR and FFR changes before and after treatment of downstream stenoses. Anatomic metrics derived from intravascular imaging modalities of intravascular ultrasound (IVUS) and optical coherence tomography (OCT) will also be validated. (AU)