2023 SCAI SHOCK

Complications of Mechanical Circulatory Support in Cardiogenic Shock

Presenter

Moein Bayat Mokhtari, MD, Lenox Hill Hospital - Northwell Health, New York, NY
Moein Bayat Mokhtari, MD1, Alexandra Young, MD1, Karsh Gaurav, MD2, Daniel Asemota, MD, MBA2 and Miguel Alvarez Villela, MD3, (1)Lenox Hill Hospital - Northwell Health, New York, NY, (2)Northwell Health Lenox Hill Hospital, New York, NY, (3)Lenox Hill Hospital - Northwell Health, new york, NY

Learning Objectives:
  1. Complications of Impella in Cardiogenic Shock
Keywords: Cardiogenic Shock, Complications, Heart Failure, Hemodynamic Support and Imaging & Physiology

Title


Complications of Mechanical Circulatory Support in Cardiogenic Shock

Introduction


Cardiogenic shock (CS) remains an important cause of mortality among patients with myocardial infarction (MI). Mechanical circulatory support (MCS) devices are gaining ground in the management of MI-related cardiogenic shock, but device-related complications remain an important barrier to their use.

Clinical Case


A 62-year-old man with a history of atrial fibrillation and type-2 diabetes presented to the hospital with 3-hours of substernal chest pain. Initial EKG showed STEMI in anteroseptal leads. An urgent coronary angiogram showed thrombotic occlusion of the ostial LAD. Primary percutaneous coronary intervention was complicated by no-reflow and ensuing CS. An Impella CP was immediately placed followed by urgent intubation.

Right heart catheterization prior to transfer to the CCU showed right atrial pressure of 6 mmHg, Pulmonary artery pressure 37/26 (28) mmHg and PCWP 18 mmHg with a Fick-Cardiac-Index of 2.1 L/min/m2">m². Soon after CCU admission dark colored urine was noted, and serial laboratory parameters were unmeasurable due to hemolysis. Appropriate position of the Impella catheter was confirmed with multiple transthoracic echocardiograms and therapeutic anticoagulation was maintained with unfractionated heparin infusion.

After 12h, profound hemolysis persisted. While the RHC hemodynamics were unchanged from initial measurement, Impella support could not be weaned below P5 due to worsening hypotension. Escalation to Impella 5.5 and VA-ECMO were contemplated, but after shock team discussion, Impella CP catheter exchange was pursued. The exchange was uneventful, and the urine discoloration improved rapidly.

Within 60 minutes, the patient suffered pulseless ventricular tachycardia requiring brief CPR and external defibrillation. After achieving ROSC, rapid hemodynamic deterioration occurred requiring escalation of ino-pressor support.

He was then escalated to VA-ECMO and the Impella CP remained for ventricular unloading. Hemolysis was not noted during ECPELLA support with clear urine and reportable laboratories. Initial LDH was 999 U/L. Per institutional protocol systemic anticoagulation was switched to Argatroban.

ECMO course was complicated by copious epistaxis requiring brief interruption of anticoagulation. On day 5 he had recovery of pulsatility and Impella was removed. Six hours after returning to CCU he had an unexplained rise in serum lactate. An urgent abdominal computed-tomography-angiography revealed extensive thrombus in the descending aorta involving the superior mesenteric and right renal artery. Despite urgent exploratory laparotomy and SMA thrombectomy, he developed multiorgan failure, refractory vasoplegia and demise.

Discussion


This case highlights the challenges facing clinicians in the current management of AMI-CS. Bleeding, thrombosis and hemolysis remain important complications related to available MCS devices. When these complications occur without a clearly reversible cause, device removal, exchange or escalation need to be considered. In this case, device removal was not felt to be an option given the ongoing need for support. Escalation also seemed unwarranted given the relatively low support level and apparent stability. Although the exchange resolved the hemolysis related to the Impella CP, the patient required escalation to VA-ECMO. This was done promptly, but eventually led to a new device-related complication that was fatal. Multidisciplinary shock teams can aid clinicians in these complex cases pending accumulation of further scientific evidence to guide care.