Cardiac anesthesiologists and LVAD patients: Pro vs Cons

There’s been a big debate re: who should care for LVAD patients… a general anesthesiologist or a cardiac anesthesiologist? See below for pros and cons of each. Ultimately, I think all anesthesiologists should be comfortable caring for these patients as we’ll see more and more LVAD patients undergoing procedures.

Troubleshooting the Left Ventricular Assist Device. Emergency Medicine. 2016 February;48(2):58-63.

LVAD Parameter Abnormalities:

High power, low-pulsatility index and fluctuating pump speed: Consider pump thrombosis or hypotension, vasodilation, initial response to exercise.
High power with high pulsatility index: Consider fluid overload, normal physiological response to increased demand; myocardial recovery.
Low power, low pulsatility index, and unchanging speed: Consider hypertension or inflow/outflow obstruction, LV failure, dysrhythmia.
Low power with normal or high pulsatility index: Consider suction event.

Pro: Cardiothoracic Anesthesiologists Should Provide Anesthetic Care for Patients With Ventricular Assist Devices Undergoing Noncardiac Surgery. JCVA, February 2017. Volume 31, Issue 1, Pages 378–381

Con: Cardiothoracic Anesthesiologists Are Not Necessary for the Management of Patients With Ventricular Assist Devices Undergoing Noncardiac Surgery. JCVA, February 2017. Volume 31, Issue 1, Pages 382–387.

Ventricular assist devices and non-cardiac surgery. BMC Anesthesiology201515:185

Goals of care for LVAD patients undergoing non-cardiac surgery should be directed at maintaining forward flow and adequate perfusion. Three main factors that affect LVAD flow are preload, RV function, and afterload.
The right ventricle is the primary means of LVAD filling; therefore, maintaining RV function is imperative.
Marked increases in systemic vascular resistance should be avoided.
Generally, decreases in pump flow should first be treated with a fluid challenge. Hypovolemia should be avoided and intraoperative losses should be replaced aggressively. Second line treatment should include inotropic support for the right ventricle.
Low-dose vasopressin (<2.4 U/h) may be the vasopressor of choice due to its minimal effect on pulmonary vascular resistance.
Standard Advanced Cardiovascular Life Support Guidelines should be followed; however, external chest compressions should be avoided during cardiac arrest.
Steep Trendelenburg may increase venous return, risking RV strain. Peritoneal insufflation for laparoscopic surgery also increases afterload and has detrimental effects on preload. Insufflation should utilize minimum pressures and be increased in a gradual, step-wise fashion.
TEE can be extremely valuable in diagnosing the cause of obstruction.

Perioperative management of patients with left ventricular assist devices undergoing noncardiac surgery. Annals of cardiac anaesthesia 2016. Vol 19, Issue 4: 676-686.

LVAD: What Should I report? Feb 2017 ASE conference. **ECHO**

Higher the RPMs (pump speed)
- More LV compression, smaller LV size
- Less functional MR
- More AI, less AV opening
- Less LVED diameter
De Novo Aortic Regurgitation Post LVAD
- Proposed mechanisms
  - Aortic valve remains closed during systole
  - Commissural fusion of the aortic valve from disuse
  - Subsequent degeneration of valve
  - Turbulent blood backflow from small outflow cannula onto a closed valve
  - Persistent elevation of aortic root pressure –> aortic root dilation and valve incompetence
- Treatment
  - Lower LVAD speed (but that may worsen mitral regurgitation)
  - Aortic valve surgery or percutaneous intervention
  - Heart transplant
RV Fractional Area Change (RV FAC)
- RVFAC is a rough measure of RV systolic function (4 chamber view)
- RVFAC = (RVEDA – RVESA) / RVEDA
- Normal RVFAC = 35 – 63%

Ventricular Assist Device (VAD). LifeInTheFastLane.com. December 11, 2016.

Care of the LVAD patient PPT. Summit 2014.

Pulsatility Index:
- normally decrease as pump speed is increased

LVAD: Understanding equipment and Alarms. Duke Heart Center PPT.

LVAD Management in the ICU. Crit Care Med 2014; 42:158–168.

Screen Shot 2018-11-26 at 11.20.26 AM — From Left Ventricular Assist Device Management in the ICU Pratt, Alexandra K. MD1; Shah, Nimesh S. MD1; Boyce, Steven W. MD2 Critical Care Medicine: January 2014 – Volume 42 – Issue 1 – p 158–168 doi: 10.1097/01.ccm.0000435675.91305.76 Concise Definitive Review

Screen Shot 2018-11-26 at 11.20.47 AM — Left Ventricular Assist Device Management in the ICU Pratt, Alexandra K. MD1; Shah, Nimesh S. MD1; Boyce, Steven W. MD2 Critical Care Medicine: January 2014 – Volume 42 – Issue 1 – p 158–168 doi: 10.1097/01.ccm.0000435675.91305.76 Concise Definitive Review

Anesthesia for Left Ventricular Assist Device Insertion: A Case Series and Review. Ochsner J. 2011 Spring; 11(1): 70–77.

Medical Management of Patients With Continuous-Flow Left Ventricular Assist Devices. Curr Treat Options Cardiovasc Med. 2014 Feb; 16(2): 283.

My blog posts:

HeartWare vs. HeartMate LVAD

Ventricular Assist Devices: Impella

HeartWare vs. HeartMate LVAD

A couple of weeks ago, I took care of a patient who desperately needed to get better from acute CHF. At that time, we placed the patient on an impella… but the next day, it was deemed that he needed ECMO to reperfuse his organs. After a week on ECMO with continued impella support, ECMO was titrated down and off while maintaining 3.9L/min flow from the impella. During the wean off ECMO, the patient had been extubated and was mentating clearly and interacting appropriately.

Fast forward a couple days after getting extubated, the patient was ripe for an LVAD. But which one? (We ended up placing the patient on HeartWare LVAD).

YouTube: LVAD 101 – Anatomy & Physiology

YouTube: LVAD Pathophysiology

HeartWare

HeartWare brochure

YouTube vid of HeartWare (no sound) ; Vid of HeartWare with detailed explanation

HeartMate II

HeartMate II website

YouTube vid of HeartMate II

Summary

Cost-effectiveness: HeartWare > HeartMate II (UK NHS study, April 2014)
LV Geometry: HeartWare = HeartMate II (J CT Surg, 2013)
Stroke & GI bleed risk: HeartWare > HeartMate II (J Card Surg 2013)
Risk of device failure: HeartWare < HeartMate II
ENDURANCE trial: Randomized patients eligible for DT 2:1 to the HeartWare centrifugal flow LVAD versus the HeartMate II axial flow LVAD. The trial did reach its primary noninferiority endpoint of stroke free survival at 2 years (55.0% in the HeartWare patients versus 57.4% in the HeartMate II patients). Of note, a change in the design of the HeartWare device during the trial (sintering of the inflow cannula) appeared to decrease the incidence of pump thrombosis. Overall, the stroke rate was higher in the HeartWare arm whereas device malfunctions requiring exchange or urgent transplantation were more common in the HeartMate II arm. Data analysis suggested that better blood pressure control in the HeartWare arm may decrease the stroke rate and a second cohort of patients is being enrolled with more attention being paid to blood pressures management.

ROADMAP study: (Risk Assessment and Comparative Effectiveness of Left Ventricular Assist Device and Medical Management in Heart Failure Patients) was an observational study of the Thoratec HeartMate II LVAD compared to optimal medical management in patients with advanced heart failure. Thirty day mortality was the same in both groups (1%) while one year survival was 80% in the LVAD group compared to 64% in the medical group (on an as treated basis). Functional status and quality of life improved significantly more in the LVAD group (analyzed by 6 minute walk, health related quality of life, and NYHA class). Unfortunately, adverse events in the LVAD group remained similar to what was previously reported in the DT trial, with bleeding being the most frequent adverse event.
Bridge to Transplant: HeartWare = HeartMate II (Ann Thor Surg, Feb 2014)
ADVANCE trial (bridge to transplant): 94% survival at 180 days with HeartWare
PPT: LVAD Update 2015
Anesthesia for LVAD
TEE:

Ventricular Assist Devices: Impella

“There’s an emergent case coming for impella placement.”

Impella? I’ve read about these devices and I’m familiar with managing patients on LVADs as well as providing anesthesia for LVAD placement. But, I’ve never done an Impella on a critically unstable patient.

YouTube video describing the purpose and placement of the Impella

Cath Lab Digest: Overview of Impella 5.0