Tianrong Xie

Real-time three-dimensional dobutamine stress echocardiography in assessment of ischemia: comparison with two-dimensional dobutamine stress echocardiography

Abstract OBJECTIVES This study was designed to test the feasibility and efficacy of using real-time three-dimensional echocardiography (RT-3D) to detect ischemia during dobutamine-induced stress (DSE) and compares the results with conventional two-dimensional echocardiography (2D). BACKGROUND Real-time three-dimensional echocardiography, a novel imaging technique, offers rapid acquisition with multiple simultaneous views of the left ventricle (LV). These features make it attractive for application during stress. METHODS Of 279 consecutive patients screened for image quality by 2D, 253 patients with adequate images underwent RT-3D and 2D within 30 s of each other at baseline and at peak DSE. RESULTS Real-time three-dimensional echocardiography and 2D showed good concordance in detection of abnormal LV wall motion at baseline (84%: Kappa = 0.59) and at peak DSE (88.9%: Kappa = 0.72). Left ventricular wall motion scores were similar at baseline and peak DSE using both techniques. Interobserver agreements for detection of ischemia at peak DSE were superior for RT-3D, 92.7% compared with 84.6% for 2D (p CONCLUSIONS Real-time three-dimensional dobutamine stress echocardiography is feasible and sensitive in the detection of CAD. The procedure offers shorter scanning time, superior interobserver agreements and unique new views of the LV.

Assessment of Left Atrial Appendage by Live Three‐Dimensional Echocardiography: Early Experience and Comparison with Transesophageal Echocardiography

Background: Live Three‐Dimensional Echocardiography (L3D, Sonos 7500, Philips) has the potential to visualize all cardiac structures including left atrial appendage (LAA). We tested the feasibility of evaluating LAA by L3D and compared the findings to transthoracic echocardiography (2D) and in a subset of patients with transesophageal echocardiography (TEE). Methods: L3D images were obtained in 204 consecutive patients referred for routine 2D or TEE. We performed wide‐angled acquisitions from parasternal and apical views. TomTec system (4D Cardio‐view, RT 1.2) was used to visualize LAA from multiple vantage points. Results: LAA was adequately visualized by L3D in 139 of 204 (68.1%) patients. L3D visualization was dependent on image quality, suboptimal in 100 and diagnostic in 104 patients. Overall, LAA was visualized in 93 (45.5%) patients by 2D compared to 139 (68.1%) by L3D (P < 0.0001). In 100 patients with suboptimal image quality by L3D, LAA visualization was 16% by 2D and 35% by L3D, whereas in 104 patients with diagnostic images, LAA was visualized in 77 (74%) by 2D and in all 104 (100%) patients by L3D (P < 0.0001). In 37 patients referred for transesophageal echocardiography (TEE), live three‐dimensional echocardiography (L3D) visualized left atrial appendage (LAA) in 34 patients with diagnostic image quality. Eight patients with LAA thrombi on TEE had thrombi detected by L3D as well. All patients with LAA thrombus had enlarged LA by both 2D and TEE. Conclusions: L3D is a promising technique in evaluation of LAA with and without thrombi. In patients with good quality transthoracic images L3D may be used as a screening tool in assessment of LAA.

Color M-mode flow propagation velocity versus conventional Doppler indices in the assessment of diastolic left ventricular function in patients on chronic hemodialysis.

Background and Objective: Color M‐mode flow propagation velocity (Vp) has been reported as a preload‐independent measure of diastolic function. To study the effects of loading conditions on diastolic function assessment in patients on chronic hemodialysis, we measured Vp and conventional Doppler indices pre‐ and posthemodialysis. Methods: Twenty hemodialysis patients with normal systolic function underwent measurement of Vp, early filling velocity (E), its deceleration time (DT), atrial contraction velocity (A), isovolumic relaxation time (IVRT), and pulmonary atrial flow reversal velocity (PFR) pre‐ and posthemodialysis. Twelve healthy controls underwent these same measurements. Results: Hemodialysis patients had significantly slower Vp at baseline than normal controls, while E/A, DT, IVRT, and pulmonary flow reversal were not significantly different. E, IVRT, and PFR were affected by hemodialysis, while color M‐mode flow propagation velocities, A, and DT were not. Conclusions: Color M‐mode flow propagation velocity seems to be a preload‐independent measure of diastolic function in chronic hemodialysis patients in whom isolated diastolic dysfunction appears prevalent.

Real-Time Three-Dimensional Echocardiography With Real-Time Volume Rendering in Assessment of Left Ventricular Apical Thrombi

A 36-year-old man with dilated cardiomyopathy was admitted for worsening congestive heart failure. A 2D echocardiogram showed enlargement of the left chambers with global left ventricular hypokinesis; ejection fraction was estimated at 35%. Mild regurgitations of the mitral and tricuspid valves were noted, and the pulmonary artery pressure was estimated at 43 to 48 mm Hg. An echo-dense mass, most consistent with a thrombus, was seen at the apex of the left ventricle. Visualization was partial in the apical views and full in the subcostal view. The …

Color M-mode flow propagation velocity and conventional Doppler indices in the assessment of diastolic left ventricular function during isometric exercise

Background and objective: Color M‐mode flow propagation velocity (Vp) was shown to be a preload‐independent measure of diastolic function. To study the effects of an increase in afterload induced by isometric handgrip exercise on diastolic function assessment in patients with cardiomyopathy, we measured Vp and conventional Doppler indices at baseline and at 30% of predetermined maximum handgrip strength. Methods: Twenty‐four patients with systolic dysfunction were divided into two groups: Group I comprising 12 patients with E/A < 1 (early filling velocity/atrial contraction velocity) and Group II comprising 12 patients with E/A > 1. All the patients underwent measurement of Vp, E velocity, its deceleration time (DT), A velocity, isovolumic relaxation time (IVRT), and pulmonary atrial flow reversal velocity (PFR) at baseline and at 30% of predetermined maximum handgrip strength. Twelve healthy controls underwent these same measurements. Results: When comparing baseline to peak echocardiographic data, no significant changes were noted in Vp in any of the groups while a shift of pulsed Doppler indices of Group I toward a pattern closer to that of Group II was noted and a decrease in E velocity and E/A ratio with an increase in IVRT occurred in healthy controls. Conclusions: Color M‐mode flow propagation velocity seems to be an afterload‐independent measure of diastolic function in patients with moderate to severe cardiomyopathy while pulsed Doppler indices are more sensitive to loading conditions induced by isometric exercise.

Live 3-D echocardiography in monitoring transcatheter closure of patent foramen ovale

Transesophageal echocardiography (TEE) is routinely used in monitoring transcatheter closure of patent foramen ovale (PFO).1 However the technique requires mental reconstruction of 2-dimensional images for estimation of the shape and size of PFO. Live 3-D Echocardiography (3-D, Sonos 7500 Philips, Bothel, WA) provides unique en-face views of PFO and has the potential to precisely define its size and shape.2,3

Real time three-dimensional echocardiography and endovascular stenting.

A 52‐year‐old male with HIV and chronic renal failure presented with 2‐day history of fever and chills. He had recent superior vena cava (SVC) stent placement for SVC stenosis following multiple dialysis‐catheter insertions. Patients blood cultures grew methicillin‐resistant staphylococcus aureus. Two‐dimensional (2D) echocardiography showed no vegetations. With high clinical suspicion, 2D transesophageal echocardiogram (TEE) was obtained and confi rmed no endocarditis and patent stent at SVC right atrial junction; however, entire stent was not visualized. Simultaneous three‐dimensional TEE provided superior views of SVC stent in cross‐sectional and longitudinal planes, clearly demonstrating patent stent without vegetations, stenosis, migration, or thrombosis.