Diagnostic accuracy of transthoracic echocardiography to detect structural abnormalities of the outflow graft in patients with left ventricular assist devices

Tasuku Sato; Takeo Fujino; Kayo Misumi; Toru Hashimoto; Takamori Kakino; Akira Shiose; Kohtaro Abe

doi:10.1093/ehjimp/qyag017

Diagnostic accuracy of transthoracic echocardiography to detect structural abnormalities of the outflow graft in patients with left ventricular assist devices

Eur Heart J Imaging Methods Pract. 2026 Mar 9;4(1):qyag017. doi: 10.1093/ehjimp/qyag017. eCollection 2026 Jan.

Authors

Tasuku Sato¹, Takeo Fujino^{2

3}, Kayo Misumi³, Toru Hashimoto³, Takamori Kakino³, Akira Shiose⁴, Kohtaro Abe³

Affiliations

¹ Heart Center, Kyushu University Hospital, 3-1-1, Maidashi, Higashi-ku,Fukuoka 812-8582, Japan.
² Department of Advanced Cardiopulmonary Failure, Faculty of Medical Sciences, Kyushu University, 3-1-1, Maidashi, Higashi-ku, Fukuoka 812-8582, Japan.
³ Department of Cardiovascular Medicine, Faculty of Medical Sciences, Kyushu University, 3-1-1, Maidashi, Higashi-ku, Fukuoka 812-8582, Japan.
⁴ Department of Cardiovascular Surgery, Faculty of Medical Sciences, Kyushu University, 3-1-1, Maidashi, Higashi-ku, Fukuoka 812-8582, Japan.

Abstract

Aims: Structural abnormalities of the outflow graft (OG), such as kinking or external obstruction, are recognized as serious complications in patients with left ventricular assist devices (LVADs). Generally, these abnormalities can be evaluated by contrast-enhanced computed tomography (CT) or angiography; however, the utility of transthoracic echocardiography (TTE) remains unclear.

Methods and results: This single-centre retrospective study included adult patients with LVADs who underwent both TTE and contrast-enhanced CT between January 2015 and December 2022. TTE evaluation employed a standardized protocol using subcostal and right parasternal approaches. OG structural abnormalities were defined as bending of ≥90°, or stenosis of ≥50%. The diagnostic accuracy of TTE was assessed using CT as the reference standard. Of 90 patients with LVADs, 54 patients (62 examinations of both TTE and CT) met inclusion criteria. Among 62 examinations, OG structural abnormalities were identified in 18 examinations by CT (12 proximal, 7 distal, 1 both). TTE demonstrated a sensitivity of 61% and specificity of 100% overall. Sensitivity was 33% for proximal and 71% for distal abnormalities.

Conclusion: TTE is an accurate and non-invasive modality for detecting OG structural abnormalities, particularly in distal segment. However, its diagnostic performance for proximal OG lesions is limited, likely due to acoustic interference and anatomical constraints. Further refinement of imaging techniques may enhance the utility of TTE in LVAD management.

Keywords: external outflow graft obstruction; left ventricular assist device; outflow graft; transthoracic echocardiography.