Prognostic value of combined coronary CT angiography and myocardial perfusion imaging in women and men

Abstract Funding Acknowledgements Type of funding sources: Public grant(s) – National budget only. Main funding source(s): State Research Funding for Turku University Hospital. Background Combined anatomical and functional imaging enables detection of non-obstructive and obstructive coronary artery disease (CAD) as well as myocardial ischemia, and also provides prognostic information. Purpose We evaluated sex differences in disease phenotype and adverse outcomes by using non-invasive combined anatomical and functional imaging in symptomatic patients with suspected CAD. Methods We retrospectively evaluated patients undergone coronary computed tomography angiography (CTA) for suspected CAD. According to local routine, patients with suspected obstructive stenosis on CTA were referred to downstream 15O-water positron emission tomography (PET) myocardial perfusion imaging to assess stress myocardial blood flow (MBF; ≤2.3 mL/g/min considered abnormal). A composite adverse endpoint was recorded, including all-cause death, myocardial infarction, and unstable angina pectoris. Results A total of 1948 patients (59% women) underwent coronary CTA of whom 657 (34%) patients underwent downstream PET perfusion imaging. During a mean follow-up of 6.8 years, 182 adverse events occurred. Women more often had normal coronary arteries (42% vs. 22%, p<0.001) and less often abnormal stress MBF (9% vs. 28%, p<0.001), as compared with men. The annual adverse event rate was lower in women versus men (1.2% vs. 1.7%, p = 0.02). Both in women and men, coronary calcification, non-obstructive CAD, and abnormal stress MBF were independent predictors of events. Abnormal stress MBF was associated with 5.0 and 5.6-fold adverse event rates in women and men, respectively. There was no statistical interaction between sex and coronary calcification, non-obstructive CAD, or abnormal stress MBF in terms of predicting adverse outcome. Conclusion Among patients evaluated for chronic chest pain, women have lower prevalence of ischemic CAD and lower rate of future adverse events. Combined coronary CTA and PET myocardial perfusion imaging predicts outcomes equally in women and men.