Discussion:
COVID-19 was confirmed in a cluster of patients by the Chinese health authorities on January 7, 2020. The first case in the United States was reported on January 20, 2020. With its continued spread globally, a range of complications affecting almost every organ system have been reported.
Cardiac tamponade is most commonly idiopathic, with a smaller subset of cases resulting from infectious causes. It can be due to collection of transudate, exudate or blood in the pericardium. Viral pericarditis is usually characterized by a gradual accumulation of transudate. Interestingly, in COVID-19 patients with cardiac tamponade, some develop sanguineous fluid collection while others have an exudative or transudative pericardial fluid, as evidenced in our patients.
The pathophysiology of COVID-19 cardiac tamponade is possibly a result of the marked systemic inflammatory response to the virus, leading to myocarditis and pericarditis. Myocardial ischemia, as evidenced by elevated or up-trending troponin levels, can also be explained by the hyper-coagulability (resulting from endothelial damage and the inflammatory response) in these patients. Thus, prophylactic use of corticosteroids and therapeutic anti-coagulation have been proposed in COVID-19 patients.
Cardiac tamponade should be suspected in COVID-19 patients with progressive hemodynamic compromise, especially if the usual constellation of physical exam findings associated with cardiac tamponade is present. An echocardiogram showing late diastolic collapse of the right atrium and early diastolic collapse of the right ventricle (occurring when the intra-pericardial pressure exceeds intracavitary pressure) is diagnostic. Of note, CXR does not demonstrate cardiac enlargement until at least 200 mL of pericardial fluid has accumulated and thus has low sensitivity.
After pericardial fluid drainage management is largely supportive, and recurrent cardiac tamponade is possible. While the use of therapeutic anticoagulation has been shown to improve prognosis in severe COVID-19 patients the development of sanguineous cardiac tamponade (as seen in Case 1) may point towards increased risks of therapeutic anticoagulation after initial drainage. However, given the documented benefits of therapeutic anticoagulation in COVID-19 patients, particularly in patients with elevated D-dimers, it might be judicious to resume anti-coagulation 12 hours post-operatively, with a high index of suspicion for rebleeding in case of progressive worsening of hemodynamic status. The role of NSAIDs in this subpopulation is yet to be determined. High suspicion for recurrence of cardiac tamponade is warranted as risk of recurrence is as high as 20%.
While current data on cardiac tamponade, with possible concomitant biventricular failure, in COVID-19 patients are limited, we hypothesize that short-term prognosis in this subpopulation is primarily dependent upon ventricular function at the time of development of tamponade. In our case series, the two patients with cardiac tamponade with concomitant biventricular failure (Cases 2 and 3) experienced rapid deterioration leading to death, while the patient with preserved ventricular function (Case 1) survived. However, the observed ventricular dysfunction – possibly stress cardiomyopathy or cytokine-related myocardial dysfunction – may just be a manifestation of the overall severity of inflammatory response and the associated fulminant cytokine release (Tables 1-3). Further, the long-term prognosis, sequelae and predictors of survival in COVID-19 patients developing transient myocarditis or cardiac tamponade remain yet to be
Importantly, surgical intervention and drainage of pericardial fluid in COVID-19 patients, while allowing for rapid relief from tamponade physiology, is associated with intra- and post-operative risks. Anesthesia, mechanical ventilation, and use of vasopressors and inotropic medications may contribute to long-term pulmonary and cardiovascular compromise and increased mortality in COVID-19 patients. Thus, pericardiocentesis, with its minimal risk of anesthesia, may be preferable in this subpopulation.