An innovative approach to treat left ventricular assist device outflow graft obstruction—the basket-handle technique^†

Abstract

Left ventricular assist device (LVAD) outflow graft obstruction (OGO) is a serious complication that often requires surgical intervention. Standard approaches involve cardiopulmonary bypass (CPB) or veno-arterial extracorporeal membrane oxygenation (vaECMO) to facilitate outflow graft clamping and shortening. We present a surgical approach to reduce the need for CPB or vaECMO for outflow graft shortening. A 25-year-old female presented for routine LVAD follow-up with reduced device flow. Computed tomography angiography revealed outflow graft obstruction due to external compression from accumulated material between the outflow graft and the bend relief, along with graft elongation. To correct this, we performed outflow graft revision and shortening using a Dacron prosthesis as a bypass from the proximal to the distal outflow graft, avoiding CPB or vaECMO. LVAD flow was immediately restored postoperatively, and the patient recovered without complications. Follow-up computed tomography angiography confirmed full resolution of the obstruction with no recurrence. Managing LVAD outflow graft obstruction is particularly challenging when accompanied by elongation. The basket-handle technique offers a safe and effective alternative to traditional methods, allowing for outflow graft shortening without CPB or vaECMO, thereby reducing procedural risks and promoting faster patient recovery.

INTRODUCTION

Left ventricular assist device (LVAD) outflow graft obstruction (OGO) is a rare but serious condition in patients undergoing LVAD therapy. Its prevalence increases after 1 year of LVAD support [1]. Causes include rotation, elongation and external compression by substance accumulation between outflow graft and its bend relief. The outflow graft twist may result from rotation due to Heartmate 3 pump movement and cardiorespiratory motion with cardiac remodelling, leading to mechanical obstruction [2]. Further outflow graft elongation can occur from suboptimal surgical placement during implantation. Clinical symptoms can appear as reduced LVAD flow with elevated power consumption and signs of left and/or right ventricular failure. Thoracic computed tomography angiography (CTA) imaging of the outflow graft is standard procedure for the diagnosis of OGO. In case of outflow graft elongation accompanying or causing the OGO, shortening of the outflow graft demands the use of CPB or vaECMO support to facilitate clamping and shortening of the outflow graft. We present a surgical technique for outflow graft shortening using a Dacron prosthesis as the bypass from the proximal to the distal outflow graft, allowing clamping and shortening in between.

PATIENT AND METHODS

Ethical statement

Written informed consent of the patient and all participants for publishing this case was given.

Patient

A 25-year-old female with LVAD therapy after implantation via a full sternotomy abroad in May 2018 was admitted to our facility. She presented with multiple syncopations without evidence for signs of ventricular failure, aside from reduced LVAD flow to 3.6 L/min (baseline flow up to 5 L/min). A CTA scan showed external compression most likely due to substance accumulation between the outflow graft and the bend relief plus kinking of the outflow graft (Fig. 1A and B). The patient’s international normalized ratio at admission was in the therapeutical range (2.08).

Surgery and technique

The patient underwent surgical revision of the outflow graft via a full resternotomy. The intraoperative situs featured extensive adhesions, especially at the diaphragmatic pericardial edge. The outflow graft was revealed and dissected gently. After splicing the bend relief and removing substance accumulation, the decision to shorten the outflow graft was made using the so-called basket-handle technique. This technique involves a Dacron prosthesis (10 mm) with an end-to-side anastomosis to the outflow graft near the LVAD pump and the aortal insertion, bypassing the outflow graft and allowing clamping in between (Fig. 2A). The outflow graft was shortened without CPB or vaECMO support. After shortening, an end-to-end anastomosis of the outflow graft was performed. The stumps of the Dacron prosthesis were clamped near the outflow graft and oversewn using 5/0 Prolene (Fig. 2B).

RESULTS

After shortening the outflow graft and removing the external OGO, the LVAD flow was immediately restored from 3.6 to 4.7 L/min. After 1 day in the intensive care unit, the patient showed constant stability regarding LVAD and haemodynamic parameters and was transferred to the general ward on postoperative day 1. The postoperative CTA scan presented a normal outflow graft without signs of residual OGO (Fig. 1C). The patient was discharged home 17 days after the operation in good general health.

DISCUSSION

Surgical therapy for OGO in LVAD therapy is challenging. Our report shows that vaECMO support or cardiopulmonary bypass is not inevitable for outflow graft shortening. Cardiopulmonary bypass for treatment of OGO is rare, especially since fully magnetically levitated centrifugal flow was introduced in LVAD therapy [3, 4]. In cases of external OGO without outflow graft kinking or elongation, surgical decompression by splicing the bend relief can be an option. An urgent heart transplant or an intraluminal stent are other options for OGO treatment [5, 6]. An intraluminal stent can yield favourable outcomes in selected patients but should only be considered if intraluminal thrombosis was ruled out [7, 8].

Operative access via a sternotomy was mandatory for our patient due to suspected outflow graft elongation. At our centre, using vaECMO bypassing the femoral vein and arterial cannulation of the distal part of outflow graft with a Dacron graft has been standard for outflow graft shortening. The presented case was the first time we used this innovative technique, and the surgical result, plus the subsequent LVAD data, was promising.

In the recent literature, no description of similar surgical techniques for outflow graft shortening can be found. The basket-handle bypass allows avoidance of vaECMO or CPB and its possible complications.

CONCLUSION

Outflow graft obstruction in LVAD therapy is a rare but challenging complication. Surgical treatment options are individualized, and case-by-case decisions remain mandatory. In the presented case, an immediate flow increase occurred after shortening, and the patient left the hospital with stable LVAD data. The basket-handle bypass technique offers an attractive option to avoid CPB or vaECMO support during outflow graft shortening in cases of OGO caused or accompanied by elongation. This technique shows that CPB or vaECMO is not mandatory for facilitating outflow graft shortening and can be used instead of CPB or vaECMO support.

ACKNOWLEDGEMENTS

We would like to thank Johannes Kroll for inventing this technique and his involvement in implementing his surgical abilities into our department.

FUNDING

None declared.

Conflicts of interest: Martin Czerny reports consultancy fees from Medira and consultancy for Terumo Aortic, Medtronic and Endospan; a one-time direct personal payment (speaking honorarium) from Abbott; payment to his institution from Terumo aortic for post-market registries for study nurses. Martin Czerny holds shares from TEVAR Ltd and from Ascense Medical. David Schibilsky is a consultant for Abiomed and received travel grants from Abbott.

DATA AVAILABILITY

All data are included in the article itself.

Reviewer information

The European Journal of Cardio-Thoracic Surgery thanks Antonio Loforte and the other anonymous reviewers for their contributions to the peer review process of this article.

Footnotes

REFERENCES