ABSTRACT
Introduction An increased risk of pulmonary emboli (PE) has been reported in COVID-19 disease, possibly as a result of a hypercoagulable state. Superadded PE's may exacerbate respiratory failure and lead to increased morbidity and mortality. The objective of this study was to review the detection rates for PE in patients with COVID-19 undergoing CTPA scanning. Secondary objectives were to explore correlations between PE diagnosis, serum markers and radiological COVID-19 severity. Methods A total of 325 patients had a CTPA performed between 30/03/2020-15/05/2020. Data was retrospectively collected on patient demographics, COVID-19 status, radiological severity (British Society of Thoracic Imaging classification), PE location and biochemical markers (D-Dimer, Troponin-I, CRP, Ferritin). Results 122/325 patients were diagnosed with COVID-19 either radiologically (n=20, 16%) or by RT-PCR (n=102, 84%). The PE detection rate on imaging was significantly higher in those with COVID-19 than those without (32/122 [26%] and 27/203 [13%] respectively [p=0.005]). 617 patients were hospitalised with COVID-19 during this period (total PE incidence 5.2% [32/617]). Radiological severity of COVID-19 lung disease was not associated with PE detection (p=0.94). Initial quantitative D-Dimer's were significantly higher in COVID-19 patients with PE than those without (median 4390 [range 761-20,000] and 930 [range 110-20,000] respectively [p<0.001]). Higher D-Dimer levels were associated with increased PE detection rates on CT imaging (Abstract P253 figure 1). COVID-19 associated PE's were more likely to be unilateral (16/32 compared to 5/27 in COVID-19 negative group [p=0.025]) and trended towards more distal vessels (p=0.09). Accounting for age, an additional PE diagnosis did not significantly affect in-hospital COVID-19 mortality (OR 1.54 [CI 0.52-3.94], [p=0.38]). Conclusion Our results demonstrate increased detection of PE in COVID-19. Emboli are more likely to be unilateral, and more distally located. We postulate this may be due to higher rates of in-situ thrombosis rather than distant embolisation of clots. The radiological severity of COVID-19 lung disease does not appear to be strongly linked to PE detection rates which may suggest the hypercoagulable state in COVID-19 is independent from the inflammatory lung process. Patients with COVID-19 and co-existent PE's have significantly higher DDimer's, and further evaluation is needed into their use as a screening tool.
ABSTRACT
P253 figure 1).COVID-19 associated PE’s were more likely to be unilateral (16/32 compared to 5/27 in COVID-19 negative group [p=0.025]) and trended towards more distal vessels (p=0.09). Accounting for age, an additional PE diagnosis did not significantly affect in-hospital COVID-19 mortality (OR 1.54 [CI 0.52–3.94], [p=0.38]).Abstract P253 Figure 1(a): Initial D-Dimer levels in COVID-19 patients without (L) and with (R) PE diagnosis on CTPA. (b): Proportion of CTPA’s diagnosing a PE at specified D-Dimer ranges[Figure omitted. See PDF]ConclusionOur results demonstrate increased detection of PE in COVID-19. Emboli are more likely to be unilateral, and more distally located. We postulate this may be due to higher rates of in-situ thrombosis rather than distant embolisation of clots. The radiological severity of COVID-19 lung disease does not appear to be strongly linked to PE detection rates which may suggest the hypercoagulable state in COVID-19 is independent from the inflammatory lung process. Patients with COVID-19 and co-existent PE’s have significantly higher D-Dimer’s, and further evaluation is needed into their use as a screening tool.