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.