3. Discussion:
This case demonstrates an unusual presentation of pheochromocytoma as acute myocarditis complicated by pulmonary edema, cardiogenic shock and cardiac arrest.
Pheochromocytoma is a rare catecholamine-secreting tumor associated with several catecholamine-induced cardiovascular complications. Adrenergic myocarditis is a rare serious complication of pheochromocytoma4-7.
Myocarditis is caused by the chronic exposure and the sudden excessive release of catecholamine. Actually, the long-term elevation of adrenaline and noradrenaline leads to downregulation of β-adrenoreceptors leading to suboptimal function of myofibers and decreased number of contracting units.
Therefore, heart failure symptoms are the common presentation of adrenergic myocarditis, which makes it difficult to render a definite diagnosis6.
It has been suggested that an acute hemorrhagic necrosis of the tumor may cause an abnormally high catecholamine release which lead to cardiogenic shock7 . This finding concord with our case in which the adrenal mass has a frankly hemorrhagic CT density and MRI signal.
On the other hand, there has been a concern regarding the failure to diagnose covid-19 cases since the outbreak of the pandemic mostly due to the absence of any specific signs. This applies to viral myocarditis which has been reported in the literature as an initial cardiac complication of covid-19. Many patients experienced tachycardia and acute-onset heart failure with cardiogenic shock. Yet, no specific echocardiographic features of myocarditis exist8.
Diagnostic gold standards for myocarditis are endomyocardial biopsy or cMRI (during the acute phase). Nevertheless, according to a position statement of the ESC diagnosis can be made from clinical and biochemical findings9. In our case, the diagnosis of adrenergic myocarditis was based on clinical, laboratory and echocardiography findings. Unfortunately, endomyocardial biopsy is not performed in our country.
The presence of fever on admission could be explained by the cytokine release from pheochromocytoma cells10.
The prognosis of patients with pheochromocytoma-associated adrenergic cardiomyopathy depends greatly on its early diagnosis1. The later, despite being crucial to avoid life-threatening complications, is often challenging. The present pandemic makes it even worse since it mandates the exclusion of Covid-19 pneumonia in patients with acute dyspnea3. Myocardial injuries are also common in covid-19 patients, accounting for 7 to 23 % of the reported cases in Wuha11.
In conclusion, adrenergic cardiomyopathy is a rare entity with a variable clinical presentation. It can be fulminant and life-threatening. Nowadays, the need to exclude the possibility of COVID-19 pneumonia in patients with acute dyspnea in previously healthy adults may cause a delay in the diagnosis and treatment, which increases the risks of morbidity and mortality.