@article {Graf175, author = {Senta Graf and Aliasghar Khorsand and Marianne Gwechenberger and Clemens Novotny and Kurt Kletter and Heinz Sochor and Christian Pirich and Gerald Maurer and Gerold Porenta and Manfred Zehetgruber}, title = {Typical Chest Pain and Normal Coronary Angiogram: Cardiac Risk Factor Analysis Versus PET for Detection of Microvascular Disease}, volume = {48}, number = {2}, pages = {175--181}, year = {2007}, publisher = {Society of Nuclear Medicine}, abstract = {Angiography of patients with typical chest pain reveals normal epicardial coronary arteries in about 20\%. Coronary flow reserve (CFR) determination is an elaborate, but helpful, task, as only the evidence of microvascular disease enables appropriate therapy. We prospectively evaluated the incidence of a dysfunctional microcirculation and searched for predictive parameters of a reduced CFR. Methods: In 79 consecutive patients (52 females, 27 males) with typical angina and a normal angiogram and 10 control subjects (6 females, 4 males), CFR was measured by 13N-ammonia rest/dipyridamole PET and correlated with clinical parameters individually and summarized as the number of risk factors (NRF) using an elaborated cardiac risk factor score. Results: Sixty-five percent of patients had a reduced CFR (CFR \< 2.5). CFR correlated with NRF (r = 0.55, P \< 0.001), systolic blood pressure (r = 0.46, P \< 0.001), interventricular septal thickness (r = 0.33, P \< 0.01), and age (r = 0.25, P = 0.02). Eighty-five percent of patients with a high risk factor score (NRF >= 5) had a reduced CFR. In contrast, 100\% of our patients with a low risk factor score (NRF \< 2) presented a normal CFR. In total, 55\% of our patients could be allocated to either one of these groups. Conclusion: In about two thirds of patients, anginal pain can be explained by a reduced CFR. Risk factors have a cumulative negative effect on CFR. A clinical cardiac risk factor analysis enables estimation of individual probability of microvascular dysfunction in a significant proportion of these patients. However, CFR measurements are recommended for those with an intermediate NRF.}, issn = {0161-5505}, URL = {https://jnm.snmjournals.org/content/48/2/175}, eprint = {https://jnm.snmjournals.org/content/48/2/175.full.pdf}, journal = {Journal of Nuclear Medicine} }