ABSTRACT
BACKGROUND: Coincidental extracardiac findings with increased perfusion were reported during myocardial perfusion imaging (MPI) with various retention radiotracers. Clinical parametric O-15-H2O PET MPI yielding quantitative measures of myocardial blood flow (MBF) was recently implemented at our facility. We aim to explore whether similar extracardiac findings are observed using O-15-H2O. METHODS AND RESULTS: All patients (2963) were scanned with O-15-H2O PET MPI according to international guidelines and extracardiac findings were collected. In contrast to parametric O-15-H2O MBF images, extracardiac perfusion was assessed using summed images. Biopsy histopathology and other imaging modalities served as reference standards. Various malignant lesions with increased perfusion were detected, including lymphomas, large-celled neuroendocrine tumour, breast, and lung cancer plus metastases from colonic and renal cell carcinomas. Furthermore, inflammatory and hyperplastic benign conditions with increased perfusion were observed: rib fractures, gynecomastia, atelectasis, sarcoidosis, pneumonia, chronic lung inflammation and fibrosis, benign lung nodule, chronic diffuse lung infiltrates, pleural plaques and COVID-19 infiltrates. CONCLUSIONS: Malignant and benign extracardiac coincidental findings with increased perfusion are readily visible and frequently seen on O-15-H2O PET MPI. We recommend evaluating the summed O-15-H2O PET images in addition to the low-dose CT attenuation images.
ABSTRACT
Background Cardiovascular complications from COVID-19 contribute to its high morbidity and mortality. The effect of COVID-19 infection on the coronary vasculature is not known. The objective of this study was to investigate the prevalence of coronary vasomotor dysfunction identified by coronary flow reserve from cardiac positron emission tomography in patients with previous COVID-19 infection. Methods and Results All patients who had polymerase chain reaction-confirmed SARS-CoV-2 infection referred for myocardial stress perfusion positron emission tomography imaging at Brigham and Women's Hospital from April 2020 to July 2021 were compared with a matched control group without prior SARS-CoV-2 infection imaged in the same period. The main outcome was the prevalence of coronary vasomotor dysfunction. Myocardial perfusion and myocardial blood flow reserve were quantified using N13-ammonia positron emission tomography imaging. Thirty-four patients with prior COVID-19 were identified and compared with 103 matched controls. The median time from polymerase chain reaction-confirmed SARS-CoV-2 to cardiac positron emission tomography was 4.6 months (interquartile range,1.2-5.6 months). There were 16 out of 34 (47%) patients previously hospitalized for COVID-19 infection. Baseline cardiac risk factors were common, and 18 (53%) patients in the COVID-19 group had abnormal myocardial perfusion. Myocardial blood flow reserve was abnormal (<2) in 44.0% of the patients with COVID-19 compared with 11.7% of matched controls (P<0.001). The mean myocardial blood flow reserve was 19.4% lower in patients with COVID-19 compared with control patients (2.00±0.45 versus 2.48±0.47, P<0.001). Conclusions Myocardial blood flow reserve was impaired in patients with prior COVID-19 infection compared with cardiovascular risk factor-matched controls, suggesting a relationship between SARS-CoV-2 infection and coronary vascular health. These data highlight the need to assess long-term consequences of COVID-19 on vascular health in future prospective studies.