Advanced 3-D analysis, client-server systems, and cloud computing-Integration of cardiovascular imaging data into clinical workflows of transcatheter aortic valve replacement

Abstract

Degenerative aortic stenosis is highly prevalent in the aging populations of industrialized countries and is associated with poor prognosis. Surgical valve replacement has been the only established treatment with documented improvement of long-term outcome. However, many of the older patients with aortic stenosis (AS) are high-risk or ineligible for surgery. For these patients, transcatheter aortic valve replacement (TAVR) has emerged as a treatment alternative. The TAVR procedure is characterized by a lack of visualization of the operative field. Therefore, pre- and intra-procedural imaging is critical for patient selection, pre-procedural planning, and intra-operative decision-making. Incremental to conventional angiography and 2-D echocardiography, multidetector computed tomography (CT) has assumed an important role before TAVR. The analysis of 3-D CT data requires extensive post-processing during direct interaction with the dataset, using advance analysis software. Organization and storage of the data according to complex clinical workflows and sharing of image information have become a critical part of these novel treatment approaches. Optimally, the data are integrated into a comprehensive image data file accessible to multiple groups of practitioners across the hospital. This creates new challenges for data management requiring a complex IT infrastructure, spanning across multiple locations, but is increasingly achieved with client-server solutions and private cloud technology. This article describes the challenges and opportunities created by the increased amount of patient-specific imaging data in the context of TAVR.

Keywords: Cloud computing; aortic stenosis; computed tomography; imaging; transcatheter aortic valve implantation.

Figure 1

LVOT and aortic root: using an advanced 3-D analysis program (syngo VIA, Siemens Medical Solutions), multiplanar reconstruction of the left ventricular outflow tract (LVOT) and aortic root is performed. The left sided panels show orthogonal MPR reconstructions of the aortic root, with the image plane focused on the annulus. A volume rendered image (VRI) image of the aortic root with the visible centerline is shown. The right sided panels show images reconstructed along and perpendicular to the centerline. Measurements are captured and saved as findings (bottom of the screen)

Figure 2

Aortic annulus, close-up: this figure shows a close-up image of the aortic annulus (right panel). Annulus measurements are performed at the lowest insertion point of the aortic valve leaflets. Measurements include the minimum and maximum diameter, circumference, and area

Figure 3

LV function: using advanced analysis software, segmentation of the LV cavity and myocardium can be performed. If performed in multiple phases of the cardiac cycle, this allows calculation of left ventricular ejection fraction (LVED). The left handed quadrants show images reconstructed into 4-chamber, 2-chamber, and short axis views. The calculated EF is displayed. The right handed quadrants show a visual summary of wall motion in a ‘bulls-eye’ view

Figure 4

Using an advanced 3-D analysis program, multiplanar reconstruction of the iliac arteries is performed. The image shows 3-D MPR multi-planar reconstruction at the iliac arteries. Panels 1-3 show orthogonal MPR reconstructions of the right iliac artery, with the cross-hair focused on the right external iliac segment. Panel 4 shows a VRI image of the aorta. Panel 5 and 6 show images reconstructed along and perpendicular to the centerline. The results are saved as ‘bookmarks’ in the Findings Navigator (panel 7)

Figure 5

This figure shows reconstructions of the iliac arteries using volume rendered imaging (VRI). The right panel shows an angiographic view with focus on the calcification

Figure 6

The images reconstructed with an advance analysis software can be saved and displayed together with axial imaes in the PACS. This figure shows a sceenshow of a 3-monitor PACS station with images of the annulus and and the centerline of the right iliac artery

Figure 7

If PACS and EHR are integrated, display of reports and ‘Key Images’ is also possible in the EHR. This figure shows the report page (left) and images of the iliac artery (right)

Figure 8

This figure shows a table with automatically populated measurements, transfered and displayed into the EHR record

Figure 9

This cartoon summarized the complex structure of a ‘private cloud’

Figure 10

This complex network structure is summarized in this simplified sketch. The data center and the integrated anlysis and storage systems allow bi-directional communication, essentially establishing a ‘private cloud’ of data