Pheochromocytoma crisis represents an unpredictable, life-threatening endocrine emergency characterized by massive catecholamine surges, acute hypertensive emergencies, and sudden cardiovascular collapse. Although clinicians occasionally encounter catecholamine-induced cardiogenic shock, postpartum presentations accompanied by refractory arrhythmias and acute respiratory failure remain exceedingly rare. In a landmark clinical case, intensivists deployed veno-arteriovenous ECMO to rescue a 34-year-old postpartum woman following cardiac arrest. This advanced triple-cannulation configuration provided indispensable cardiopulmonary support, bridging the patient to definitive adrenalectomy.

Clinical Presentation and Postpartum Pheochromocytoma Crisis

Pregnancy and the puerperium can obscure classical clinical signs of pheochromocytoma. Consequently, clinicians frequently misattribute headache, palpitations, and hypertension to preeclampsia or gestational hypertension. In this case, a 34-year-old woman presented two days postpartum with hypertensive emergency and acute respiratory failure. Diagnostic computed tomography quickly identified an 18-centimeter left adrenal mass characteristic of a catecholamine-producing tumor. Such massive lesions release vast amounts of epinephrine and norepinephrine directly into the systemic circulation. Therefore, myocardial adrenergic receptors undergo profound desensitization, microvascular vasospasm, and direct toxic damage. Furthermore, labor contractions and rapid postpartum uterine changes can cause mechanical tumor compression or acute intratumoral necrosis. As a result, sudden catecholamine flooding precipitates severe vascular resistance and acute left ventricular strain. Because these manifestations mimic peripartum cardiomyopathy, clinicians require high vigilance, rapid cross-sectional imaging, and prompt plasma metanephrine testing to establish the diagnosis.

Hemodynamic Collapse and Pheochromocytoma Cardiac Arrest

The clinical course of a pheochromocytoma crisis can deteriorate rapidly from severe hypertension into profound cardiogenic shock. In this patient, intense sympathetic overstimulation triggered recurrent ventricular arrhythmias and subsequent cardiac arrest. Endogenous catecholamines cause excessive myocardial calcium overload, impairing electromechanical coupling and provoking electrical instability. In addition, extreme alpha-1 receptor vasoconstriction abruptly increases left ventricular afterload, promoting acute pulmonary edema and respiratory failure. Meanwhile, acute adrenergic storm impairs myocardial contractility, generating an acute inverted Takotsubo pattern. Although chest compressions achieved return of spontaneous circulation, the patient suffered from refractory ventricular arrhythmias and hemodynamic collapse. Standard pharmacological interventions often fail because exogenous vasopressors worsen intracellular calcium toxicity. Consequently, mechanical circulatory support became essential to prevent ischemic brain injury and multiorgan failure. Advanced mechanical assistance permitted myocardial rest while allowing endogenous catecholamines to metabolize safely.

Indications and Cannulation for Veno-Arteriovenous ECMO

When patients suffer combined cardiopulmonary collapse, conventional extracorporeal life support configurations present distinct hemodynamic limitations. For example, standard venoarterial (VA) ECMO drains venous blood and reinfuses it retrogradely into the femoral artery. However, when concurrent respiratory failure impairs pulmonary oxygen exchange, the native left ventricle ejects deoxygenated blood into the ascending aorta. Consequently, cerebral and coronary circulations endure profound hypoxia, a complication known as Harlequin syndrome. Conversely, venovenous (VV) ECMO relieves hypoxemia but fails to support severe cardiogenic shock. To resolve this dilemma, intensivists initiated veno-arteriovenous ECMO. This hybrid strategy combines venous drainage from the femoral vein with split arterial and venous reinfusion cannulas. Therefore, the femoral arterial cannula maintains systemic perfusion pressure, while the internal jugular cannula delivers oxygenated blood directly to the right atrium. As a result, the heart ejects fully oxygenated blood to the brain and coronary arteries.

Overcoming Differential Hypoxemia and Arrhythmic Storm

Managing veno-arteriovenous ECMO requires continuous titration of blood flow between the arterial and venous reinfusion limbs. Intensivists adjust line resistance to ensure adequate flow through the internal jugular cannula. Thus, right radial arterial oxygen saturation remains safely above physiological hypoxemia thresholds. Simultaneously, systemic arterial reinfusion preserves critical renal and hepatic perfusion. Furthermore, mechanical ventricular unloading reduces left ventricular end-diastolic pressure and myocardial oxygen demand. Because mechanical decompression relieves wall stress, lethal ventricular arrhythmias rapidly subsided in this patient. Meanwhile, clinicians gradually weaned toxic doses of inotropes and instituted combined alpha-adrenergic blockade using intravenous phentolamine. By blocking alpha-receptors prior to beta-blockade, clinicians averted paradoxical hypertensive spikes. Ultimately, over several days of extracorporeal support, pulmonary gas exchange resolved, ventricular contractility normalized, and the multidisciplinary team achieved successful decannulation.

Surgical Adrenalectomy and Multidisciplinary Recovery

Following successful decannulation from mechanical support, definitive management mandates complete surgical resection. However, performing an adrenalectomy on a postpartum patient after recent cardiac arrest carries formidable perioperative hazards. Therefore, surgeons delayed the operation until the patient achieved full cardiovascular recovery and sustained pharmacological alpha-blockade. Clinicians replenished contracted intravascular volume with intravenous crystalloids and maintained close arterial line monitoring. Once hemodynamic stability was established, endocrine surgeons performed an uncomplicated open resection of the 18-centimeter adrenal tumor. During tumor manipulation, anesthesiologists managed blood pressure fluctuations with short-acting intravenous vasodilators. Furthermore, after adrenal vein ligation, they administered fluids to counteract sudden post-resection hypotension. Histopathological examination confirmed a completely excised pheochromocytoma. The patient experienced an uneventful recovery with fully normalized cardiac ejection fraction. Consequently, this case highlights how advanced mechanical support bridges critically ill patients to definitive surgical cure.

Why can pheochromocytoma present as an acute postpartum emergency?

Uterine contractions during labor, mechanical compression from the gravid uterus, and postpartum involution frequently alter intra-abdominal pressures. These physical stresses can trigger sudden capsular rupture, hemorrhage, or massive catecholamine release from an unsuspected adrenal tumor. Furthermore, clinicians often misdiagnose the initial symptoms as severe preeclampsia or eclampsia. Consequently, unchecked catecholamine toxicity precipitates acute pulmonary edema, malignant arrhythmias, and refractory cardiogenic shock shortly after delivery.

What advantage does V-AV ECMO offer over standard VA ECMO?

Standard peripheral venoarterial ECMO sends retrograde oxygenated blood upward from femoral vessels. However, if the patient develops severe respiratory failure, poorly oxygenated blood from native lungs enters the coronary and carotid arteries, causing upper-body differential hypoxemia. By adding an extra venous reinfusion cannula into the right atrium, the veno-arteriovenous configuration pre-oxygenates native pulmonary blood flow. Consequently, it effectively protects the brain and recovering myocardium from severe hypoxia while simultaneously maintaining systemic circulatory support.

When should surgical adrenalectomy occur after acute pheochromocytoma stabilization?

Emergency adrenalectomy during an unoptimized acute adrenergic crisis carries maternal mortality rates exceeding thirty percent. Therefore, surgeons should delay adrenalectomy until the patient achieves full hemodynamic stabilization, organ recovery, and successful decannulation from mechanical support. Clinicians must establish adequate alpha-adrenergic blockade for at least ten to fourteen days beforehand to expand contracted plasma volume and normalize systemic vascular resistance. Then, experienced endocrine surgeons can resect the adrenal tumor with minimal intraoperative complications.

Disclaimer: This content is for informational and educational purposes only and does not constitute medical advice, diagnosis, or treatment. Healthcare professionals should exercise their independent clinical judgment when applying this information. Patient presentations and clinical circumstances vary, and management strategies must be individualized. The authors and publishers disclaim any liability for adverse outcomes resulting from the application of this information. Refer to the latest local and national guidelines for clinical practice.

References

1. Agyei K et al. Case Report: Veno-Arteriovenous Extracorporeal Membrane Oxygenation for Management of Pheochromocytoma-Induced Cardiac Arrest in a Post-Partum Patient. A A Pract. 2026 Oct 01. doi: 10.1213/XAA.0000000000002309. PMID: 42874048.
2. Forin E, Golino G, Bianco F, et al. Pheochromocytoma crisis managed with veno-arterial extracorporeal membrane oxygenation: a case report. Ann Palliat Med. 2025;14(3):9227.
3. Colson P, Gaudard P, Coves R, Zeroual N, Eliet J. Life-Threatening Pheochromocytoma Crisis Operated On Emergency Under Extracorporeal Life Support: About 4 Case Reports. Clin Surg. 2019;4:2305.
4. Lenders JWM, Kerstens MN, Amar L, et al. Genetics, diagnosis, management and future directions of research of phaeochromocytoma and paraganglioma: a position statement and clinical practice guidelines of the European Society of Endocrinology. Eur J Endocrinol. 2020;182(5):G1-G32.