To the Editor:
We read with great interest the letter from Rajendram and colleagues1 in response to our previous publication of a young patient presenting with a severe pulmonary embolism as an initial symptom of a coronavirus disease 2019 (COVID-19) infection.2 We reported our clinical experience and insisted on the facts that the initial workup showed the patient had a patent foramen ovale with clot into it, which made us choose the surgical treatment rather than an intravenous thrombolytic therapy. After the surgical embolectomy, mechanical ventilation of our patient was difficult, with refractory hypoxemia. Although this was somehow improved by prone positioning, the patient was supported with extracorporeal membrane oxygenation and died of multiorgan failure soon after.
Rajendram and colleagues1 very interestingly hypothesized that platypnea-orthodeoxia syndrome with a right-to-left interatrial shunt, in relation with the initial patent foramen ovale, might have played a crucial role. We do not think this was possible in our patient because the patent foramen ovale was closed during the cardiac operation with a polypropylene running suture. Moreover, no interatrial shunt was seen in the various echocardiograms done in the postoperative period. In our opinion, improvement of blood gas exchange in prone decubitus was mostly due to the release of posterior atelectasis in an obese patient as in “classic” acute respiratory distress syndrome.3 We think that parenchymal severe inflammatory aggression was per se the main mechanism of lung failure in our patient.
Also, it is important to underline that unlike in the initial period, when we published our article, in the last 3 weeks, almost 65 publications have showed the link and the high frequency between COVID-19 and pulmonary embolism. These proximal or distal thromboses of lung vessels may also present a preponderant factor in the impairment of pulmonary oxygenation in COVID-19 patients.
References
- 1.Rajendram R., Kharal G.A., Puri R. COVID-19 may be exacerbated by right-to-left interatrial shunt (letter) Ann Thorac Surg. 2021;111:376. doi: 10.1016/j.athoracsur.2020.05.013. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 2.Fabre O., Rebet O., Carjaliu I., Radutoiu M., Gautier L., Hysi I. Severe acute proximal pulmonary embolism and COVID-19: a word of caution. Ann Thorac Surg. 2020;110:e409–e411. doi: 10.1016/j.athoracsur.2020.04.005. [DOI] [PMC free article] [PubMed] [Google Scholar]
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