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Rapid aortic valve movement can be recorded by 3-dimensional echocardiography and analyzed quantitatively. Time and velocity indices of valve dynamics are influenced by valvular and myocardial factors. A comparable in vivo analysis is not possible with any other imaging procedure.

Background-Common 3D systems have only limited spatial and temporal resolution (frame rate of 25 Hz). Thin structures such as cardiac valves are not imaged exactly; rapid movement patterns cannot be precisely recorded. The objective of the present project was to achieve radiofrequency (RF) data transmission to the 3D workstation to improve image resolution. Methods and Results-A commercially available echocardiographic system (5-MHz transesophageal echocardiography probe) with an integrated raw data interface enables transmission of RF data (up to 40 megabytes per second). A 3D data set may contain up to 3 gigabytes, so that all of the high-resolution ultrasound information of the 2D image is available. Frame rates of up to 168 Hz result in temporal resolution 6 times that of standard 3D systems. The applicability of the system and the image quality were tested in 10 patients. The structure of the aortic valve and the dynamic changes were depicted by volume rendering. The changes in the orifice areas were measured in frame-by-frame planimetry. The mean number of frames recorded per cardiac cycle was 122Ϯ16. The improved structural resolution enabled a detailed imaging of the morphology of the aortic cusps. The rapid systolic movement patterns were recorded with up to 51 frames. The high number of frames enabled creation of precise area-time diagrams. Thus, the individual phases of aortic valve movement (rapid opening, slow valve closing, and rapid valve closing) could be analyzed quantitatively. Key Words: echocardiography, 3D Ⅲ valve, aortic Ⅲ imaging T he impetus for the technical development of 3D echocardiography was its greater diagnostic potential than that of 2D examinations. 1,2 The spatial imaging of cardiac structures is especially important in the planning and performance of surgical and catheter interventional procedures. 3,4 In addition, new possibilities of quantitative analysis, such as the determination of ventricular size and function, are also offered. 5,6 Establishing 3D echocardiography as a clinical routine procedure requires, however, further technical improvements in spatial and temporal image resolution. Conclusion-The rationale for the technical realization of radiofrequency (RF) data transmission from the ultrasound unit to the 3D workstation via a raw data interface is the attendant considerable improvement in spatial and temporal image resolution. In this article, we present a system in which the frame rate has been increased 6 times to 168 Hz. Practical applicability and image quality of the system were tested under clinical conditions. Methods Data Acquisition SetupThe investigations were performed using a PowerVision 6000 ultrasound system (Toshiba Corp) equipped with a 5-MHz multiplane transesophageal echocardiography (TEE) probe and a digital RF data output. A 3D system with modified Echo-Scan software (TomTec GmbH) was used as a control unit. RF data were acquired at a data rate of 40 megabytes per second using a parallel input/ output interface. RF data were directly transmitte...

ImportanceUltrasound renal denervation (uRDN) was shown to lower blood pressure (BP) in patients with uncontrolled hypertension (HTN). Establishing the magnitude and consistency of the uRDN effect across the HTN spectrum is clinically important.ObjectiveTo characterize the effectiveness and safety of uRDN vs a sham procedure from individual patient-level pooled data across uRDN trials including either patients with mild to moderate HTN on a background of no medications or with HTN resistant to standardized triple-combination therapy.Data SourcesA Study of the ReCor Medical Paradise System in Clinical Hypertension (RADIANCE-HTN SOLO and TRIO) and A Study of the ReCor Medical Paradise System in Stage II Hypertension (RADIANCE II) trials.Study SelectionTrials with similar designs, standardized operational implementation (medication standardization and blinding of both patients and physicians to treatment assignment), and follow-up.Data Extraction and SynthesisPooled analysis using individual patient-level data using linear regression models to compare uRDN with sham across the trials.Main Outcomes and MeasuresThe primary outcome was baseline-adjusted change in 2-month daytime ambulatory systolic BP (dASBP) between groups.ResultsA total of 506 patients were randomized in the 3 studies (uRDN, 293; sham, 213; mean [SD] age, 54.1 [9.3]; 354 male [70.0%]). After a 1-month medication stabilization period, dASBP was similar between the groups (mean [SD], uRDN, 150.3 [9.2] mm Hg; sham, 150.8 [10.5] mm Hg). At 2 months, dASBP decreased by 8.5 mm Hg to mean (SD) 141.8 (13.8) mm Hg among patients treated with uRDN and by 2.9 mm Hg to 147.9 (14.6) mm Hg among patients treated with a sham procedure (mean difference, −5.9; 95% CI, −8.1 to −3.8 mm Hg; P < .001 in favor of uRDN). BP decreases from baseline with uRDN vs sham were consistent across trials and across BP parameters (office SBP: −10.4 mm Hg vs −3.4 mm Hg; mean difference, −6.4 mm Hg; 95% CI, −9.1 to –3.6 mm Hg; home SBP: −8.4 mm Hg vs −1.4 mm Hg; mean difference, −6.8 mm Hg; 95% CI, −8.7 to −4.9 mm Hg, respectively). The BP reductions with uRDN vs sham were consistent across prespecified subgroups. Independent predictors of a larger BP response to uRDN were higher baseline BP and heart rate and the presence of orthostatic hypertension. No differences in early safety end points were observed between groups.Conclusions and RelevanceResults of this patient-level pooled analysis suggest that BP reductions with uRDN were consistent across HTN severity in sham-controlled trials designed with a 2-month primary end point to standardize medications across randomized groups.Trial RegistrationClinicalTrials.gov Identifier: NCT02649426 and NCT03614260

Aortic stenosis is a challenge for three-dimensional (3-D) echocardiographic image resolution. This is the first study evaluating both 3-D anyplane and 3-D volume-rendered echocardiography in the quantification of aortic stenosis. In 31 patients, 3-D echocardiography was performed using a multiplane transesophageal probe. Within the acquired volume dataset, five parallel cross sections were generated through the aortic valve. Subsequently, volume-rendered images of the five cross sections were reconstructed. The smallest orifice areas of both series were compared with the results obtained by two-dimensional (2-D) transesophageal planimetry and those calculated by Doppler continuity equation. No significant differences were found between Doppler (0.76 +/- 0.18 cm(2)), 2-D echocardiography (0.78 +/- 0.24 cm(2)), and 3-D anyplane echocardiography (0.72 +/- 0.29 cm(2)). The orifice area measured smaller (0.54 =/- 0.31 cm(2), P < 0.001) by 3-D volume-rendered echocardiography. Bland-Altmann analysis indicated that for 3-D anyplane echocardiography, the mean difference from Doppler and 2-D echocardiography was - 0.04 +/- 0.24 cm(2) and - 0.06 +/- 0.23 cm(2), respectively. For 3-D volume-rendered echocardiography, the mean difference was -0.23 +/- 0.24 cm(2) and - 0.25 +/- 0.26 cm(2), respectively. In the subgroup with good resolution in the 3-D dataset, close limits of agreement were obtained between 3-D echocardiography and each of the reference methods, while the subgroup with poor resolution showed wide limits of agreement. In conclusion, planimetry of the stenotic aortic orifice by 3-D volume-rendered echocardiography is feasible but tends to underestimate the orifice area. Three-dimensional anyplane echocardiography shows better agreement with the reference methods. Accuracy is influenced strongly by the structural resolution of the stenotic orifice in the 3-D dataset.