Vivid 7

Echocardiograms of patients with congenital and structural heart disease were selected retrospectively from the routine clinical imaging database of the Department of Cardiology III—Adult Congenital and Valvular Heart Disease at the University Hospital Muenster. Echocardiograms were chosen for diversity of underlying disease etiology (see Table 1), comprehensiveness of echocardiographic views and quality of acquired loops. In addition, echocardiograms of patients without a cardiac abnormality were prospectively included according to the aforementioned criteria. The examinations were performed on different echocardiography machines from different vendors (especially GE Vivid E9, Vivid E95, Vivid 7; Philips EPIC 7C, EPIC 7G, iE33). Two-dimensional (2D) echocardiographic studies performed according to current guideline recommendations [1 (link)] were anonymized, exported and converted into individual frames in a PNG format for automated analysis. In total, individual frames of 17 separate TTE views were obtained. Figure 1 details the utilized echocardiography views.

The Doppler ultrasonic diagnostic apparatus used was GE Vivid7 and Philips IE33 with 2.0–5.0MHz transducer. Patients were examined in left lateral position. The left ventricular long axis view, apical four-chamber view, large artery short axis view and suprasternal view were used in scanning with special attention to the structures of the atria, ventricles, aorta and their interconnections. The anatomical structure of the heart was probed carefully in left ventricular long axis view, large artery short axis view and apical four-chamber view so as to confirm whether or not there are other cardiovascular anomalies. The suprasternal views were used to observe the aortic arch, aortic arch branches and descending aorta in order to determine the location of the CoA and to measure the coarctation inner diameter and scope. Color Doppler was used to observe the blood flow and measure the maximum speed and differential pressure in the location of the CoA.
In this study, the accuracy rate of two-dimensional echocardiography, color Doppler and continuous wave Doppler for CoA diagnosis for 53 patients were intercompared. At the same time, the consistency comparison of the diagnosis of echocardiogram with CTA/Aortography and surgery were also analyzed.

Doppler echocardiography was realized at rest with a standard ultrasound system (Sonos 5500 Ultrasound, from 2000 to 2003; IE33, Philips, Netherlands and Vivid 7 GE Ultrasound, Norway, from 2003 to 2015). A single experienced cardiologist reviewed and analyzed stored images through dedicated software (Xcelera R4.1, Philips Medical Systems), according to recommendations [20 (link)].
Right heart function was considered in terms of contractility and remodeling, the former expressed by TAPSE, the latter by the RV dimension (RVEDD, mm), and the right atrial area (RAA, cm²). Doppler sampling of tricuspid regurgitation velocity (TRV, m/s) was used to derive the right ventriculo-atrial systolic pressure gradient through the simplified Bernoulli’s equation. Right atrial pressure (RAP) was estimated from the dimension and inspiratory collapse of the inferior vena cava, according to the current recommendations [21 (link)]. Non-invasive sPAP was obtained adding RAP to the right ventriculo-atrial systolic pressure gradient. The efficiency of the cardiopulmonary unit was expressed through the TAPSE/sPAP (mm/mmHg) and the TAPSE/tricuspid regurgitation velocity (TAPSE/TRV, mm∙(m/s)^-1).

Two-dimensional (2D) echocardiographic imaging consisting of AP4 cine loops with exactly three cardiac cycles were included. At our centre, these studies were obtained by certified sonographers and read by level III-trained echocardiography cardiologists on the same day. The echo cine data were captured using a variety of ultrasound machines from different manufacturers and models, including GE (Vivid i, Vivid E9, Vivid7, and Vivid E95; Milwaukee, WI, USA) and Philips (iE33, SONOS, EPIQ 7C; Bothell, WA, USA), with the majority of the data obtained from the Philips iE33 model. Syngo Dynamics (Siemens Medical Solutions, Ann Arbor, MI, USA) was the archiving and analysis platform for this study, and TomTec was used for strain analyses. The gold standard for cardiac rhythm was the echocardiography cardiologists’ interpretation of the ECG rhythm strip at the time of echocardiogram, in addition to imaging assessment of the full study including Doppler. The rhythm was additionally confirmed with an external 12-lead ECG, reviewed by a staff cardiologist, around the time of each echocardiography study to account for similar irregular rhythms that may be undifferentiable on the echocardiogram rhythm strip alone. When possible, two consecutive ECGs around the time of echocardiography were examined to acknowledge the possibility of paroxysmal AF.