Presentations

Abstract

Introduction:

Type B Aortic Dissection (TBAD) is a life-threatening condition with a high mortality rate, presenting unique and challenging management considerations. Often patients present with complicating comorbidities and procedure complications. The management of TBAD has seen significant advancements over the past two decades, with the development of less invasive endovascular techniques such as Thoracic Endovascular Aortic Repair (TEVAR). However, the choice of treatment must be individualized, considering the patient's overall condition and the specific characteristics of the dissection.

Case Information:

We present a case report of the complex multidisciplinary management of a TBAD as a complication of extracorporeal membrane oxygenation (ECMO) cannulation in a patient with chronic hypertension. The patient, a 73-year-old male, presented to the Emergency Department with severe chest pain, subsequent cardiac arrest and resuscitation. He was diagnosed with a massive Pulmonary embolism with cor pulmonale. He required initiation of veno-arterial ECMO due to hemodynamic instability and underwent mechanical and suction thrombectomy. Following the successful thrombectomy he was diagnosed with a TBAD from zone 2-10. Given the patient's condition and the extent of the dissection, the decision was made to perform a TEVAR, which was successfully completed with significant improvement in his hemodynamics, allowing for eventual ECMO decannulation, and patient recovery.

Discussion/Clinical Findings:

After successful thrombectomy, his condition worsened, manifesting in lactic acidosis, shock liver and a cold left leg. Subsequent computed tomography angiography (CTA) findings revealed an acute TBAD of emergent nature, spanning zones 2-10. There was also a dynamic dissection flap observed via intravascular ultrasound (IVUS). These findings lead the attending vascular surgeon to conclude that the TBAD was likely resultant from endovascular stress created by the ECMO cannulation.

The patient underwent thoracic endovascular aortic repair (TEVAR) and conversion to veno-veno ECMO, which improved his acidosis.

In addition, hypertension is a well-known risk factor for aortic dissection, and it may be that the use of ECMO may further exacerbate the risk due to increased shear stress on the aortic wall.

Conclusion:

This case demonstrates the rare occurrence of an ECMO induced Aortic dissection and the successful management through TEVAR. It also underscores the importance of a multidisciplinary approach in the management of critically ill patients with complex aortic pathology. While at least one case report exists that demonstrates ECMO as a cause of a Type A aortic dissection, this appears to be a novel case highlighting ECMO use as the likely cause for TBAD. Whether this is the first case, or part of an unacknowledged trend, further research and study should seek to unearth more occurrences and explore their common characteristics.