Discussion
The incidence of thrombotic complications among patients with COVID-19
is high. In a study of 184 ICU patients with COVID-19 pneumonia, 31%
had thrombotic events despite prophylactic dose anticoagulation with
pulmonary embolism (PE) being the most frequent (81% of thrombotic
events).11Klok FA, Kruip MJHA, van der Meer NJM, et al.
Incidence of thrombotic complications in critically ill ICU patients
with COVID-19. Thrombosis Research . 2020.
https://doi.org/10.1016/j.thromres.2020.04.013 Patients with
COVID-19 pneumonia have been found to have PE in the absence of
predisposing risk factors.22Danzi GB, Loffi M, Galeazzi G, at
al. Acute pulmonary embolism and COVID-19 pneumonia: a random
association? Eur Heart J . 2020;
https://doi.org/10.1093/eurheartj/ehaa254,33Xie
Y, Wang X, Yang P, Zhang S. COVID-19 complicated by acute pulmonary
embolism. Radiology: Cardiothoracic Imaging. 2020;
2(2):e200067. We described a case of a previously healthy, young
individual critically ill patient with COVID-19 ARDS who developed a
large CIT and suffered cardiopulmonary arrest likely because of a
massive PE.
Right ventricular thrombi, or clots in transit (CIT), are uncommon and
occurring in ~4% of unselected patients with PE but are
associated with a considerable 27-45% mortality rate.44Lai E,
Alishetti S, Wong JM, et al. Right ventricular thrombus in transit:
Raising the stakes in the management of pulmonary embolism.CASE: Cardiovascular Imaging Case Reports . 2019;3(6):272-276.,55Rose
PS, Pubjabi NM, Pearse DB. Treatment of right heart thromboemboli.Chest . 2002;121(3):806-814.,66Konstantinides
SV, Myer G, Becattini C, et al. 2019 ESC Guidelines for the diagnosis
and management of acute pulmonary embolism developed in collaboration
with the European Respiratory Society (ERS): The Task Force for the
diagnosis and management of acute pulmonary embolism of the European
Society of Cardiology (ESC). Eur Heart J . 2020;41(4):543-603.
Optimal therapy for CIT is not defined as most data are based on
case-series or registry results. However, meta-analysis data suggest
superior results with thrombolytic therapy in these patients to
alternative treatment modalities.5,77Ferrari
E, Benhamou M, Berthier F, et al. Mobile thrombi of the right heart in
pulmonary embolism: delayed disappearance after thrombolytic
treatment. Chest . 2005;127(3):1051-1053. As our patient was in
cardiopulmonary arrest likely because of massive PE, tPA was the
indicated therapy.
TEE has been used as a modality to evaluate patients during
resuscitation; imaging can effectively diagnose the cause of arrest,
alter therapy, and guide chest
compressions.88Teran F,
Dean AJ, Centeno C, Panebianco NL, Zeidan AJ, Chan W, Abella BS.
Evaluation of out-of-hospital cardiac arrest using tranesophageal
echocardiography in the emergency department. Resuscitation .
2019;137:140-147.,99Parker BK, Salerno A,
Euerle BD. The Use of Transesophageal Echocardiography During Cardiac
Arrests Resuscitation: A Literature Review. J Ultrasound Med.2019;38:1141-1151. In a study of 33 patients with out-of-hospital
cardiac arrest presenting to the emergency department, 12% of those
presumed to be in asystole were found to have fine ventricular
fibrillation by TEE. Importantly, the AMC was identified to be over the
aortic root or LVOT in 53% of cases.8 TEE imaging has
demonstrated the left ventricular stroke volume was correlated with the
location of the AMC. LV stroke volume improves when AMC is over the LV
and away from the LVOT and the aorta.1010Hwang SO, Zhao PG, Choi
HJ, Park KH, Cha KC, Park SM, et al. Compression of the Left
Ventricular Outflow Tract During Cardiopulmonary Resuscitation.Acad Emerg Med . 2009;16:928-933. In our case, the AMC of the
mechanical CPR device was initially noted on TEE to be malpositioned
over the LVOT. Under TEE guidance it was repositioned over the LV to
improve chest compressions.