Use of a Ventricular Assist Device in a Single-Ventricle Patient

To the Editor:

I read with great interest the recent article by Dr. Frazier and colleagues titled “Total Circulatory Support with an LVAD in an Adolescent with a Previous Fontan Procedure.”¹

The paper is particularly intriguing because this is probably the 1st report of the use of a ventricular assist device in a patient with a single ventricle. Not too long ago, we implanted a Berlin heart LVAD (left ventricular assist device) in an infant with complex congenital heart disease and compromised circulation that needed support. The details of this case, which was complicated by heparin-induced thrombocytopenia (as was Dr. Frazier's case), have been described elsewhere.² Later, as interest rose in the potential usefulness of assist devices in the pediatric population, we considered implanting an assist device in another patient with single-ventricle physiology (after a bidirectional Glenn procedure), who presented at our institution with borderline hemodynamics. We scoured the literature for prior evidence of the use of such devices in single-ventricle patients; we found none in PubMed. I contacted colleagues in the cardiothoracic surgery community who were actively involved in the implantation of these devices into adult patients. Specifically, I inquired about their experience with the use of a ventricular assist device in single-ventricle patients. Many of my colleagues reported that these attempts had been unsuccessful and invariably led to the death of the patient. In this regard, the efforts by Frazier and colleagues should be commended and recognized as quite an accomplishment.

Frazier's discussion section was also excellent. There are several points, however, on which I would appreciate further elaboration by the authors. First, I am curious to know whether the authors have implanted assist devices in other single-ventricle patients, or if they have knowledge of the use of such devices in other patients with single-ventricle physiology. Clearly, a patient with Fontan circulation has separation of the systemic and pulmonary blood flows, which is quite different from the condition of a child with intracardiac mixing, as occurs after a bidirectional Glenn procedure.

Second, while Frazier and colleagues state that their patient's Fontan procedure was completed with a conduit connecting the interior vena cava with the pulmonary artery, their figures show a conduit from the right atrium to the pulmonary artery. Which is correct?

Third, the authors say that the mitral valve was removed in their patient to allow optimal drainage. Is that routine, or was it a response to the unique physiology of this patient?

Finally, the authors state that the patient's course was complicated by heparin-induced thrombocytopenia, but they do not discuss the management of this particular complication during the perioperative course. Would they provide details on this particular aspect of the patient's care?

I would like once again to congratulate the authors on an outstanding outcome in what seems to be the 1st successful application of a ventricular assist device to a single-ventricle patient. Their case report will serve as a good reference for future similar attempts.

Pirooz Eghtesady, MD, PhD

Cardiothoracic Surgery, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio