Extracorporeal membrane oxygenation for pheochromocytoma-induced cardiogenic shock.

BACKGROUND

Pheochromocytoma, a rare catecholamine-producing tumor, might provoke stress-induced Takotsubo-like cardiomyopathy and severe cardiogenic shock. Because venoarterial-extracorporeal membrane oxygenation (VA-ECMO) rescue of pheochromocytoma-induced refractory cardiogenic shock has rarely been reported, we reviewed our ICU patients' presentations and outcomes.

METHODS

All pheochromocytoma-induced refractory cardiogenic shock cases managed with VA-ECMO (January 2007-March 2015) were prospectively included and reviewed. We also performed a systematic review on this topic.

RESULTS

Nine patients (7 women, 2 men; 31-51 [median, 43 (IQR 36-49) years old]) were included; none had a previously known pheochromocytoma. Six of them had medical histories suggestive of the diagnosis: palpitations and headaches for several months for four, multiple endocrine neoplasia syndrome type 1 for one and recurrent Takotsubo disease for one; at hospital admission, all were hypertensive despite cardiogenic shock. Three others had an identified surgical triggering factor. All nine patients rapidly developed refractory cardiogenic shock with very severe left ventricular (LV) impairment (LV ejection-fraction range 5-20%; LV outflow-tract velocity-time integral range 3-8 cm). Seven patients' abdominal computed tomography scans showed pheochromocytoma-suggestive adrenal gland tumors (no scan during ICU stay for 2). Despite VA-ECMO implantation, three patients died of refractory multiple organ failure. For the six others, myocardial function improved and ECMO was removed 3-7 days post-implantation; α- and β-blockers were progressively introduced. Five survivors underwent pheochromocytoma excision 3 weeks-4 months post-ICU discharge, with satisfactory outcomes. One patient, whose pheochromocytoma was diagnosed 1 year after the index event, underwent uneventful surgical adrenalectomy. Systematic review retrieved 40 cases of pheochromocytoma-induced cardiogenic shock requiring mechanical support (mostly ECMO), with a mortality rate of 7%. Pheochromocytoma was removed surgically after mechanical support weaning in 31 patients and during mechanical support in 5. Four were not operated.

CONCLUSIONS

Pheochromocytoma is a rare but reversible cause of cardiogenic shock amenable to VA-ECMO rescue. Adrenal gland imaging should be obtained for all patients with unexplained cardiogenic shock. Lastly, it might be safer to perform adrenalectomy several weeks after the initial catastrophic presentation, once recovery of LV systolic function is complete.