Use of a Percutaneous Ventricular Assist Device/Left Atrium to Femoral Artery Bypass System for Cardiogenic Shock

Summary

The following article describes the stepwise procedure for placement of a device (e.g., Tandemheart) in cardiogenic shock (CS) that is a percutaneous left ventricular assist device (pLVAD) and a left atrial to femoral artery bypass (LAFAB) system that bypasses and supports the left ventricle (LV) in CS.

Abstract

The left atrial to femoral artery bypass (LAFAB) system is a mechanical circulatory support (MCS) device used in cardiogenic shock (CS) that bypasses the left ventricle by draining blood from the left atrium (LA) and returning it to the systemic arterial circulation via the femoral artery. It can provide flows ranging from 2.5-5 L/min depending on the size of the cannula. Here, we discuss the mechanism of action of LAFAB, available clinical data, indications for its use in cardiogenic shock, steps of implantation, post-procedural care, and complications associated with the use of this device and their management.

We also provide a brief video of the procedural component of device therapy, including the pre-placement preparation, percutaneous placement of the device via transseptal puncture under echocardiographic guidance and the post-operative management of device parameters.

Introduction

Cardiogenic shock (CS) is a state of tissue hypoperfusion with or without concomitant hypotension, in which the heart is unable to deliver sufficient blood and oxygen to meet the body's demands, resulting in organ failure. It is classified into stages A to E by the Society of Cardiovascular Angiography and Interventions (SCAI): stage A - patients at risk for CS; stage B - patients at beginning stage of CS with hypotension or tachycardia without hypoperfusion; stage C - classic CS with cold and wet phenotype requiring inotropes/vasopressors or mechanical support to maintain perfusion; stage D - deteriorating on current medical or mechanical support requiring escalation....

Protocol

This procedure and protocol have been approved by the institutional review board and the United States Food and Drug Administration (FDA).

1. Patient criteria

1. Include patients with CS stage B and above as defined by the SCAI consensus statement¹.
2. Include as bridge to transplant or durable left ventricular assist system in stage D heart failure.
3. Include as bridge to recovery in AMI complicated by CS.
4. Exclude contra-indication to systemic anticoagulation.
5. Exclude life-expectancy <6 months (active malignancy).
6. Exclude if there is the presence of LA thrombus.<....

Results

Clinical applications of LAFAB device
The technique and feasibility of a percutaneous trans-atrial left ventricular bypass system were first described in the 1960s by Dennis et al.^11,12. However transseptal puncture was not initially widely adopted due to complications with the septostomy technique. Over the last decade, with advancements in the field of percutaneous interventions, operators have accumulated experience with atrial septostom.......

Discussion

Hemodynamics of LAFAB device:
The hemodynamic profile of the LAFAB device is distinct from other pVADs. By draining blood directly from the LA and returning it to the femoral artery, the device bypasses the LV completely. In doing so, it reduces LV end diastolic volume and pressure, contributing to improved LV geometry, and thereby effecting a decrease in LV stroke work. However, by returning the blood back into the iliac artery/descending aorta, afterload increases. This results in .......

Materials

List of materials used in this article

Name	Company	Catalog Number	Comments
For LAFAB (TandemHeart)
Factory Supplied Equipment for circuit connections.	TandemLife
ProtekSolo 15 Fr or 17 Fr Arterial Cannula	TandemLife
ProtekSolo 62 cm or 72 cm Transseptal Cannula	TandemLife
TandemHeart Controller	TandemLife		For adjusting flows/RPM
TandemHeart Pump	LifeSPARC		Centrifugal pump
For RAPAB (ProtekDuo)
Factory Supplied Equipment to complete the circuit.	TandemLife
ProtekDuo  29 Fr or 31 Fr Dual Lumen Cannula	TandemLife
TandemHeart Controller	TandemLife		For adjusting flows/RPM
TandemHeart Pump	LifeSPARC		Centrifugal pump