David Spielvogel, MD Surgical Director, Cardiac Transplant and Mechanical Circulatory Support Gilbert Tang, MD, MSc, MBA Cardiothoracic Surgeon, Transcatheter Heart Program On behalf of the Cardiac Transplant and Mechanical Circulatory Support Team Westchester Medical Center, Valhalla, New York

OBJECTIVES

 Understand the clinical indications for ECMO therapy  Identify procedural strategies and techniques of ECMO therapy  Discuss management strategy of ECMO in the ICU  Describe the ECMO experience at Westchester Medical Center

PHYSIOLOGY of ECMO

Basic principle

:

De-saturated blood is drained via a venous cannula, CO2 is removed, O2 added through an “extracorporeal” device (an oxygenator), and the blood is then returned to systemic circulation via another vein (VV ECMO) or artery (VA ECMO)

VV ECMO

 Perfusate blood returned to systemic circulation via venous cannula – travels into right ventricle and next pulmonary vasculature and is returned to the systemic circulation  Volume removed = volume returned; therefore no net effect on CVP, ventricular filling, or hemodynamics  CO2/O2 content in arterial blood supply is that of the blood arriving to right ventricle + any effects from gas exchange from remaining pulmonary function

VA ECMO

 Replaces/augments both pulmonary and cardiac function  Perfusate mixes in the aorta with blood from left ventricle (arriving from compromised lungs); thus O2/CO2 content = content of blood returning from the circuit + that of pulmonary source;  Systemic blood flow = ECMO flow + pt’s own CO

Role of ECMO in Cardiogenic Shock

 Bridge to recovery (BTR)  Bridge to decision (BTD)  Bridge to surgery  Bridge to long-term VAD  Bridge to transplant (BTT)

IABP in Cardiogenic Shock

 Can initially stabilize patient  May not provide enough support  Requires a certain level of LV function  Limited by persistent tachycardia / arrhythmias  Does not unload the RV  Provides some pulsatile flow with ECMO

BRIDGE TO RECOVERY



Indications

• • Acute MI Acute decompensated HF • • • • • • Post-cardiotomy syndrome Acute myocarditis Severe rejection in transplant Takotsubo’s Massive PE Respiratory failure and ARDS

BRIDGE TO SURGERY



Indications

• • • • Mechanical complications of AMI VSD Severe MR from papillary muscle rupture CAD requiring CABG • Massive PE with heparin failure

BRIDGE TO Long-term VAD



Indications

• • Unable to wean off ECMO Difficult donor match for transplant • Not a transplant candidate => LVAD as Destination Therapy

BRIDGE TO TRANSPLANT



Indications

• • Unable to wean off ECMO Transplant candidate • Easy donor match for transplant

Predictors of Poor Outcomes

 Multiorgan dysfunction  ARDS with sepsis  Severe neurological injury  Long time interval between shock and initiating ECMO

CONTRAINDICATIONS

 Major CNS injury  Severe anoxia  Embolic or hemorrhagic stroke  Intracerebral hemorrhage  Multiorgan failure  Metastatic disease  Overwhelming sepsis

TWO TYPES OF ECMO:

 Veno-arterial bypass - supports the heart and lungs  Veno-venous bypass – supports the lungs only

ECMO – The Recent Past

Centrimag-ECMO

Equipment: Cannulas

 VV ECMO:  Jugular vein, femoral vein  VA ECMO  Vein: femoral  Artery:    Femoral Axillary Aorta

Equipment: Pump, Oxygenator

 Thoratec Centrimag pump & motor  Centrimag console  Maquet Quadrox oxygenator

PA Catheter IABP Venous: percutaneous Arterial: • Femoral percutaneous • Axillary graft • Aorta direct

CENTRIMAG QUADROX OXYGENATOR

R axillary artery R femoral vein

Axillary vs Femoral Cannulation

AXILLARY

    Side-arm graft sewn on Antegrade perfusion better for cerebral and aortic root oxygenation, especially when lungs not oxygenating Increased afterload Risk of arm hyper-perfusion

FEMORAL

  Percutaneous Need antegrade stick for forward perfusion   Retrograde perfusion increases atheroembolic risk Ad-mixing with cardiopulmonary circulation => indequate cerebral and aortic root oxygenation if lungs not oxygenating

Check arterial line pressure!

 High line pressure risks hyperperfusion and bleeding at axillary site  Need to Y the arterial outflow:  Bi-axillary  Axillary + femoral  Indications  Patients with large BSA  Small axillary artery

Anticoagulation

 IV Heparin, target ACT of 200-240 seconds to prevent clotting upon interference of blood with prosthetic surfaces and in stagnant areas.

 If high bleeding risk, ACT 180-220 s  Watch for platelet drop and heparin induced thrombocytopenia (HIT)

Monitoring an ECMO patient

         Continuous cerebral SaO2 CVP, PAP, CO CXR – assess pulmonary edema SvO2: 75% in VA ECMO and 85-90% on VV ECMO considered adequate as long as CO normal EtCO2 – measures return of native lung function aBG, lactate – tissue perfusion Urine output, fluid balance – renal function Labs: renal, hepatic function Platelet count

POTENTIAL RISKS

  Infection Bleeding   Brain Surgical site  Non-pulsatile flow  Renal insufficiency  Peripheral ischemia  Limb complications   Arm hyperperfusion Leg ischemia      Air in circuit Pump malfunction Clots in the circuits Heat exchanger malfunction Cannula dislodgement

Criteria for Weaning ECMO

 Pulmonary edema resolved  Minimal inotropes / pressors  End-organ dysfunction nearly recovered

ECMO Weaning Protocol

 ICU   ECMO flow down to 1-1.5 L/min for 5 min Assess CVP, PAP, CO  TTE to assess LV, RV function  OR  3000-5000 U heparin   ECMO flow down to 1 L/min Assess CVP, PAP, CO  TEE to assess LV, RV function, septal position  Explant ECMO if appropriate

Special Note on ECMO & LVAD

 Pts with LVAD need to balance flow with both LVAD and ECMO to optimize end organ perfusion  TEE to check septal position, need to unload RV  After ECMO explant, LVAD flow needs to increase b/c of LV preload increases

45 40 35 30 25 20 15 10 5 0 2007

Percutaneous VAD Experience

2008 2009 2010 2011 2012 2013 (April 10, 2013) CentriMag Tandem CardioHelp Impella

Clinical Indication (n=115)

POST TX GRAFT FAILURE; 3 RESPIRATORY; 18 CARDIOGENIC SHOCK, 66 POST CARDIOTOMY; 28

Cardiogenic Shock (n=66)

ACS; 21 ACS - Mech. Comp; 2 Arrythmia; 5 ACS - RHF; 3 Takatsubo; 1 Myocarditis; 3 ADHF; 26 RHF; 1 Severe MR; 1 Peripartum CM; 1 Lupus Carditis; 1 Idiopathic Dilated Cardiomyopathy, 1

OVERALL SURVIVAL (n=115) Survived; 58% Deceased; 42%

Weaned, 55

OUTCOMES (n=115)

VAD - DT; 5 VAD - BTT; 7 Transplant; 4 Surgery; 7 Expired on Support; 37

Device Weaned (n=55)

Indication

POST-TX GRAFT FAILURE, 3 of 3 CARDIOGENIC SHOCK, 30 of 66 POST CARDIOTOMY, 12 of 29 RESPIRATORY, 10 of 18

Device Weaned (n=55)

Survival

Survived / Discharged 84% Expired 16%

Cardiogenic Shock (n=66)

Outcomes

Weaned, 30 Expired on Support, 17 (26%) VAD - DT; 4 VAD - BTT; 6 Transplant; 4 Surgery; 5

Cardiogenic Shock (n = 66)

Device Weaned (30/66)

Survived / Discharged 80% Expired 20%

ACS Shock on ECMO at WMC

Patient Characteristics N = 21 (%) Age (mean +/- SD) Female Renal failure COPD PVD TIA / Stroke History of MI History of CHF Cardiogenic shock Prior PCI Prior CABG Ventricular tachycardiac/fibrillation Cardiac arrest requiring resuscitation IABP or Impella support prior to ECMO Predicted mortality from APACHE 4 score (mean +/- SD) - Catheterization laboratory - Operating room 61 +/- 14 years 7 (33%) 1 (5%) 2 (10%) 4 (19%) 2 (10%) 16 (76%) 8 (38%) 21 (100%) 11 (52%) 4 (19%) 11 (52%) 10 (48%) 21 (100%) 38 +/- 16% 45 +/- 16% 36 +/- 16%

Implant Data Location of ECMO implant: - Catheterization laboratory - Operating room Site of arterial outflow: - Percutaneous femoral (all placed in cath lab) - Axillary (all placed in OR) Duration of support (mean +/- SD) OUTCOMES 30-day all-cause mortality 30-day mortality by location of ECMO implant: - Catheterization laboratory - Operating room ECMO as bridge to: - Recovery - CABG - LVAD / Transplantation Prolonged ventilation Pneumonia Renal failure Stroke Irreversible neurological injury Multiorgan failure Bleeding Vascular injury N = 21 (%) 7 (33%) 14 (67%) 7 (33%) 14 (67%) 9.0 +/- 7.5 days 5 (24%) 4/7 (57%) 1/14 (7%) 9 (43%) 5 (24%) 2 (10%) 10 (48%) 3 (14%) 1 (5%) 1 (5%) 2 (10%) 1 (5%) 2 (10%) 0 (0%)

CONCLUSIONS

 Rapidly evolving technology  Increasing array of indications  Excellent “tool” for ACS with cardiogenic shock  Shifting the paradigm of “bridge to recovery”  Presently investigating the “science” behind the clinical results