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Review
. 2020 Apr;13(4):1069-1081.
doi: 10.1016/j.jcmg.2019.05.035. Epub 2019 Sep 18.

Expanding the Scope of Multimodality Imaging in Durable Mechanical Circulatory Support

Zaid I Almarzooq  1 , Anubodh S Varshney  1 , Muthiah Vaduganathan  1 , Manan Pareek  2 , Garrick C Stewart  1 , Jerry D Estep  3 , Mandeep R Mehra  4
Affiliations
Review

Expanding the Scope of Multimodality Imaging in Durable Mechanical Circulatory Support

Zaid I Almarzooq et al. JACC Cardiovasc Imaging. 2020 Apr.

Abstract

An increasing number of patients transition to advanced-stage heart failure refractory to medical therapy. Left ventricular assist systems (LVAS) provide a bridge to candidates awaiting heart transplantation and extended device durability allows permanent implantation referred to as destination therapy. Noninvasive imaging plays a pivotal role in the optimal management of patients implanted with durable mechanical circulatory support (MCS) devices. Several advances require an updated perspective of multi-modality imaging in contemporary LVAS management. First, there has been substantial evolution of devices such as the introduction of the fully magnetically levitated HeartMate 3 pump (Abbott, Abbott Park, Illinois). Second, imaging beyond the device, of the peripheral system, is increasingly recognized as clinically relevant. Third, U.S. Food and Drug Administration recalls have called attention to LVAS complications beyond pump thrombosis that are amenable to imaging-based diagnosis. Fourth, there is increased availability of multimodality imaging, such as computed tomography and positron emission tomography, at many centers across the world. In this review, the authors provide a practical and contemporary approach to multi-modality imaging of current-generation durable MCS devices. As the use of LVAS and other novel MCS devices increases globally, it is critical for clinicians caring for LVAS patients to understand the roles of various imaging modalities in patient evaluation and management.

Keywords: heart failure; left ventricular assist systems; mechanical circulatory support; multimodality imaging.

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Figures

FIGURE 1
FIGURE 1. Differences in Color Doppler Degradation Artifact in HM3 and HVAD Transthoracic Echocardiography
(A) Visualization of the HM3 inflow cannula (red asterisk) in a patient with normal, nonturbulent flow (yellow arrow) from the parasternal long axis view. (B) Color Doppler illustration from the apical 4-chamber view in the same patient with the HM3 demonstrating mild mitral regurgitation (yellow arrow) and absence of color Doppler degradation artifact compromising 2-dimensional and color Doppler visualization. (C) Color Doppler degradation artifact (red arrow) in a patient supported by the HVAD obscuring visualization and examination of the inflow cannula from the parasternal long-axis view. (D) Color Doppler degradation artifact in the same patient supported by the HVAD obscuring the color Doppler mitral regurgitation assessment. HM3 = HeartMate 3.
FIGURE 2
FIGURE 2. Representative Cases of LVAS Infection
Coronal images of CT attenuation-corrected PET (upper row) and non–attenuation-corrected PET (lower row) as well as 3D volume fused PET/CT images for LVAS infection corresponding to the percutaneous exit (A), driveline (B), cannula exterior (C), and pump pocket (D) are shown. (A) Focal area of increased metabolic activity confined to the exit site of the driveline (solid arrowhead) into the right lower abdominal wall. (B) Focal intense 18F-FDG uptake along the driveline (open arrowhead) and exit site (solid arrowhead). (C) Heterogeneous metabolic activity along the outflow cannula (open arrow) attached to the ascending aorta, more prominent in the distal portion than the proximal metallic portion near the pump. (D) Increased 18F-FDG uptake corresponding to the LVAS pump (open arrow) and cannula exterior (open arrow) connecting to the ascending aorta, confirmed on non–attenuation-corrected PET as a focal uptake at the pump pocket (open arrow). Adapted with permission from Kim J, Feller ED, Chen W, et al. FDG PET/CT for early detection and localization of left ventricular assist device infection: impact on patient management and outcome. J Am Coll Cardiol Img 2019;12:722–9. 3D = 3-dimensional; 18F-FDG = 18F-fluorodeoxyglucose; CT = computed tomography; LVAS = left ventricular assist system; PET = positron emission tomography.
FIGURE 3
FIGURE 3. Cardiac CT With IV Contrast Illustration of Inflow Cannula Malpositioning
(A) 5-chamber illustration of the HVAD inflow cannula (red asterisk) placed in the inferior apical segment and oriented immediately adjacent to the apical septal segment. (B) Short axis view confirming the inferior apical segment orientation. Although there was no obvious visual evidence of inflow obstruction or thrombus, there was inward septal motion of the mid to distal inferoapical segment. This limited systolic flow toward the inflow cannula accounted for recurring low-flow alarms without another cause, consistent with inflow cannula mal-position as opposed to a normal inflow cannula directed parallel to the LV outflow tract/mitral valve. IV = intravenous; LV = left ventricular; other abbreviations as in Figure 2.
FIGURE 4
FIGURE 4. Coronal Reformation of Contrast-Enhanced CT Demonstrating Outflow Graft Kinking
CT imaging of the outflow graft should demonstrate a smooth contour as it travels from the LVAS pump housing to the ascending aorta. When kinking occurs, as in this figure, CT reveals a significant bend in the outflow graft (white arrow). Adapted with permission from Shroff GS, Ocazionez D, Akkanti B, et al. CT imaging of complications associated with continuous-flow left ventricular assist devices (LVADs). Semin Ultrasound CT MR 2017;38:616–28. Abbreviations as in Figure 2.
FIGURE 5
FIGURE 5. Computed Tomographic Multiplanar Reformatted Images Demonstrating Outflow Cannula
(A) Normal outflow bend relief orientation. (B) Partial bend relief disconnection. (C) Complete bend relief disconnection. (D) Bend relief with a protective titanium collar. Adapted with permission from Waller AH, Dunne R, Stewart GC, et al. Evaluation of bend relief disconnection in patients supported by a HeartMate II left ventricular assist device. Circ Cardiovasc Imaging 2014;7:844–8.
FIGURE 6
FIGURE 6. CT Demonstrating HeartMate 3 Outflow Graft Twist
(A) CT chest with contrast, coronal reconstruction. Outflow graft metallic swivel joint (arrowhead) secured to the pump allows free rotation of the outflow graft after implantation to allow adjustment by the surgeon. However, this design feature can result in sporadic and insidious twisting due to pump movement late after implantation, resulting in a “candy wrapper” twist (arrow). (B) CT chest, sagittal reconstruction. Reduced cross-sectional area of outflow graft (arrow) is produced by twisting at the swivel joint, leading to partial obstruction of flow. Abbreviation as in Figure 2.
CENTRAL ILLUSTRATION
CENTRAL ILLUSTRATION. Multimodality Imaging in Left Ventricular Assist System Evaluation
Although more than 1 imaging modality may be appropriate for a given clinical scenario or suspected complication, we present select representative imaging options for clinicians. CT = computed tomography; LVAS = left ventricular assist system; PET = positron emission tomography; TTE = transthoracic echocardiogram.
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References

    1. Benjamin EJ, Blaha MJ, Chiuve SE, et al. Heart disease and stroke statistics-2017 update: a report from the American Heart Association. Circulation 2017;135:e146–603. - PMC - PubMed
    1. Ambrosy AP, Fonarow GC, Butler J, et al. The global health and economic burden of hospitalizations for heart failure: lessons learned from hospitalized heart failure registries. J Am Coll Cardiol 2014;63:1123–33. - PubMed
    1. Kirklin JK, Pagani FD, Kormos RL, et al. Eighth annual INTERMACS report: special focus on framing the impact of adverse events. J Heart Lung Transplant 2017;36:1080–6. - PubMed
    1. Mehra MR, Goldstein DJ, Uriel N, et al. Two-year outcomes with a magnetically levitated cardiac pump in heart failure. N Engl J Med 2018; 378:1386–95. - PubMed
    1. Mehra MR, Naka Y, Uriel N, et al. A fully magnetically levitated circulatory pump for advanced heart failure. N Engl J Med 2017;376:440–50. - PubMed

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