Abstract
Byline: Ahmed H Aljizeeri, KING ABDULAZIZ MEDICAL CITY-RIYADH, Riyadh, Saudi Arabia; Amjad M Ahmed, KING ABDUL-AZIZ CARDIAC CENTER, Riyadh, Saudi Arabia; Mohammed Zayed, KACC, Riyadh, Saudi Arabia; Mousa AlaliAlfaris, Riyadh, Saudi Arabia; AWADELKARIM ABDALLA ELNEAMA, King Abdulaziz Cardiac Cntr, King Abdulaziz Med City-Riyadh; Ihab Suliman, King abdulaziz cardiac center, Riyadh, Saudi Arabia; Mohsen Al Harthi, King Abdulaziz Cardiac Cntr, King Abdulaziz Med City-Riyadh; Ahmed A Alsaileek, King Abdulaziz Med City, Riyadh, Saudi Arabia; Mouaz Al-Mallah, Houston, TX Introduction:Coronary microvascular dysfunction (CMD) is an underdiagnosed cause of chest pain. The 2021 AHA/ACC guidelines do not advocate for testing in patients with chest pain and low pretest probability (PTP <15%) of coronary artery disease (CAD). The prevalence of CMD among patients with low pretest probability is not known. We sought to estimate the prevalence of CMD among patients with chest pain and a low pretest probability of CAD. Methods: We reviewed all the patients referred to positron emission tomography myocardial perfusion imaging (PET-MPI) from May 2011 to January 2022. Patients with chest pain and low PTP of CAD who had normal PET-MPI were included in the analysis. Rest and peak myocardial blood flows (MBF) were measured. Coronary flow reserve (CFR) was calculated as a ratio of peak/rest MBF. CMD was defined as CFR of <2. Results: 1873 patients (age 53.7 Ø 9.3 years, 23.6% males) with low PTP and normal PET-MPI were included in the analysis. 372 (20%) patients had MVD. Patients with CMD had lower use of angiotensin-converting enzyme inhibitors/angiotensin receptor blockers, aspirin, and statin. Diabetes, hypercholesterolemia, and hypertension did not predict CMD. However, female gender (OR: 1.7 95%CI: 1.1- 2.6, p=0.016), age (OR: 1.02 95%CI: 1.00 - 1.04, p=0.023) and BMI (OR: 1.04 95%CI: 1.02 - 1.07, p=0.001) were associated with higher likelihood of MVD. Conclusions: Coronary Microvascular Dysfunction is common among patients with chest pain, low PTP of CAD, and normal myocardial perfusion imaging. Females are more likely to have CMD. Further studies are needed to verify the prognostic value of this population.