Myocardial Perfusion PET for the Detection and Reporting of Coronary Microvascular Dysfunction

PET-determined prevalence of coronary microvascular dysfunction and different types in a cardio-metabolic risk population

“…The independent predictive value of glycosylated hemoglobin for CMD likely is a reflection of complex interactions between components of the metabolic syndrome such as increases in body weight, arterial hypertension, insulin resistance, and micro-inflammation to alter coronary microvascular function [20] , [23] . Of further interest, the classical type of normal CMF with MFR ≥ 2.0 is commonly related to normal hyperaemic MBFs also with values ≥ 2.0 mL/g/min as observed for 13 N-ammonia PET flow studies [10] . This classical type of normal CMF was observed in 74% as opposed to the endogen type in 26% in the current study.…”

“…Studies have demonstrated a close correlation between resting MBF and the rate-pressure product (defined as product of systolic blood pressure and heart rate) as a non-invasive probe of cardiac workload and therefore myocardial oxygen demand [18] , [19] . In this direction, cardiovascular conditions that increase myocardial oxygen consumption such as tachycardia, arterial hypertension, increased myocardial contractility, increased left-ventricular wall stress, and/or sympathetic activation cause a commensurate increase in resting MBF [10] . And indeed, increases in resting MBF in the endogen type of CMD were related to higher resting heart rates, SBPs, indicative of the myocardial workload in individuals with arterial hypertension observed predominantly in morbid obesity.…”

“…According to an expert panel consensus document [10] , normal coronary microvascular function (nCMF) was defined by a MFR of ≥ 2.0, while an abnormal MFR of < 2.0 signified coronary microvascular dysfunction (CMD). These groups were then subgrouped into classical type (predominantly related to alterations in hyperemic MBFs) and endogen type (predominantly related to alterations in resting MBF).…”

“…These groups were then subgrouped into classical type (predominantly related to alterations in hyperemic MBFs) and endogen type (predominantly related to alterations in resting MBF). An increase in resting MBF was defined ≥ 1.30 mL/g/min [10] .…”

“…Such PET-determined CMD carries important diagnostic and prognostic information amenable to specific medical treatment that improve symptoms and potentially patient outcome [9] . Notably, an expert panel consensus document suggests a standardization of PET-determined CMD into classical type (predominantly related to alterations in hyperemic MBFs) and endogen type (predominantly related to alterations in resting MBF), respectively, to provide a framework for the detection of microvascular angina with subsequent individualized and, thus, optimized patient care [10] .…”