N. Kelly

Feasibility of pulmonary valve imaging using three-dimensional transthoracic echocardiography.

BACKGROUND The pulmonary valve (PV) is rarely visualized in short axis with conventional two-dimensional transthoracic echocardiography (TTE). Thus, the true incidence of abnormal PV morphology in patients undergoing TTE is unknown. This study sought to evaluate the feasibility of using three-dimensional echocardiography in the morphologic assessment of the PV in short-axis. METHODS A total of 200 consecutive patients referred for routine TTE were prospectively evaluated (mean age 64 ± 16 years; 113 males). Live3D and full-volume 3D (FV3D) were performed with the feasibility of visualizing PV morphology assessed. McNemars test was used as a nonparametric comparator between Live3D and FV3D results and to assess for any significant learning curve. Chi-square test was used to determine the association between variables. RESULTS PV morphology detection rates were significantly different (P < .0001) between Live3D (60%) and FV3D (23%). The optimal plane for Live3D was the parasternal view (99%), using zoom over the PV and rotating to a short-axis image. PV short-axis cusp detection using Live3D was dependent on the initial two-dimensional PV image quality (P < .0001). CONCLUSION Live3D is feasible in evaluating PV short-axis morphology and provides incremental value in the TTE examination.

Comparison of fluoroscopic versus real-time three-dimensional transthoracic echocardiographic guidance of endomyocardial biopsies

AIMS Fluoroscopic-guided right ventricular (RV) endomyocardial biopsy (EMBx) is the conventional method for obtaining myocardial samples to assess for rejection following heart transplantation. This study was designed to assess the feasibility and accuracy of guiding RV sheath and bioptome tip position using real-time three-dimensional echocardiography (RT3DE). METHODS AND RESULTS Forty EMBx procedures were performed in 21 patients. Five procedures were in a native heart and 35 were performed following cardiac transplantation. A RV long sheath was positioned toward the mid to distal interventricular septum using fluoroscopy. RT3DE was used to correlate sheath tip position with fluoroscopic position. Bioptome tip visualization and position against the endocardium was assessed using RT3DE. Sheath tip location was repositioned in 18 cases (46%) following assessment using RT3DE, due to alignment toward the apex (9) and mid (5) or distal RV (4) free wall. The bioptome tip could be clearly visualized using RT3DE in 83% of passes. In 35% of passes, the bioptome tip was repositioned using RT3DE guidance to improve the sampling site. CONCLUSION RT3DE-guided EMBx was feasible in the majority of patients and resulted in sheath repositioning in 46% of patients and bioptome tip reorientation in 35% of cases.

The Relative Atrial Index (RAI)—A Novel, Simple, Reliable, and Robust Transthoracic Echocardiographic Indicator of Atrial Defects

BACKGROUND The detection of atrial septal defects (ASDs) and other shunts is sometimes difficult on transthoracic echocardiography. In addition, the quantitative assessment of right-heart volume loading as an indicator of significant shunting can be difficult, with subjective estimation commonly used. Thus, the initial aim of this study was to test the accuracy of a simple, noninvasive index using atrial area dimensions to detect the presence of an ASD. Subsequently, the index was used to assess the degree of normalization and remodeling of atrial size following percutaneous ASD device closure. METHODS The relative atrial index (RAI) was derived from standard apical 4-chamber views as right atrial area divided by left atrial area. RAI was calculated in patients with previously diagnosed secundum atrial defects (n=219) with no concomitant lesions and then compared with those calculated in age-matched controls (n=219). 101 of the 219 patients with secundum atrial defects underwent percutaneous device closure. Measurements were obtained before and 1 day after percutaneous closure as well as in the early (mean, 124 days) and late (mean, 390 days) stages of follow-up. RESULTS The mean RAI in patients with ASDs (1.23+/-0.23) was significantly higher than that in the age-matched normal control group (0.78+/-0.1) (P<.0001). The mean RAI in patients with ASD was also significantly higher than that in the general population (0.81+/-0.15) (P<.0001). Receiver operating characteristic curve analysis suggested that a nominal RAI cutoff value of >0.92 predicted patients with ASDs versus matched controls with 99.1% sensitivity and 90.5% specificity. After percutaneous closure, significant atrial remodeling occurred immediately, with a reduction in the mean RAI at day 1 to 0.93+/-0.16 (P<.0001) and complete normalization at early follow-up to 0.81+/-0.12. CONCLUSION The RAI, a novel and simple transthoracic parameter, reliably identifies patients with possible atrial shunting. The resolution of right atrial enlargement occurs remarkably early after percutaneous ASD closure, as demonstrated by this novel parameter.

Contrast echocardiography in Australian clinical practice.

BACKGROUND The second-generation contrast agent Definity (a perflutren microsphere) became available in Australia in mid-2007. We describe the introduction of contrast echocardiography into a high-volume quaternary teaching hospital, performing over 16,000 echocardiograms per year. Workflow protocols were developed for patient selection, contrast administration, and image acquisition and analysis. METHODS Data were prospectively collected for all contrast cases. Endocardial definition scores were derived by three independent observers before and after contrast administration, and statistically compared. RESULTS 161 patients received contrast in the first 12 months of the contrast program. There was statistically significant improvement in endocardial definition scores after contrast administration (p=0.0001), and reduction in inter-observer variability of wall motion assessment. A number of clinically significant findings (pseudoaneurysm, non-compaction, thrombus) were detected on contrast echo that were not apparent on standard 2D imaging. Adverse events were rare (0.6%) with no life-threatening events. CONCLUSIONS The introduction of a second-generation contrast agent into clinical workflow in a hospital echocardiography department resulted in a statistically significant improvement in endocardial definition, and safely provided diagnostic imaging in cases which were otherwise non-diagnostic. Inter-observer variability was reduced, and diagnostic yield increased. These results reflect previously published data, and indicate that contrast echocardiography is feasible in Australian clinical practice.

The Feasibility and Clinical Utility of Microsphere Contrast-enhanced Transthoracic Echocardiography in Adult Congenital Heart Disease.

BACKGROUND Transthoracic echocardiography (TTE) plays a key role in adult congenital heart disease (ACHD). However, a significant number of studies are nondiagnostic due to poor image quality. Enhancement of the blood pool-tissue interface with contrast-enhanced TTE (CE-TTE) can improve image quality in suboptimal studies. The aim of this analysis was to evaluate feasibility and clinical utility of CE-TTE in the assessment of patients with ACHD. METHODS A retrospective analysis of all CE-TTE performed in ACHD patients at our institution from August 2007 to May 2014 was performed. Endocardial definition scores (EDS) for each segment in the right and left ventricles were graded pre- and postcontrast imaging, as 1 = good, 2 = suboptimal, 3 = not seen. The endocardial border definition score index (EBDSI) was also calculated pre- and postcontrast imaging. RESULTS Twenty patients with ACHD had 24 CE. Summation data for all ventricular EDS for unenhanced TTE vs. CE-TTE imaging was: EDS 1 = 136 vs. 314, EDS 2 = 119 vs. 72, EDS 3 = 162 vs. 31, respectively. Wilcoxon matched-pairs rank-signed test showed a significant ranking difference (improvement) pre- and postcontrast for the combined ventricular data (P < .0001) and the individual left and right ventricular data (all P < .0001). The EBDSI for combined ventricular data using CE-TTE was significantly lower than for noncontrast imaging (1.23 ± 0.49 vs. 2.06 ± 0.62, P < .0001). There was one minor contrast adverse reaction. CONCLUSIONS CE-TTE resulted in significantly improved right and left ventricular endocardial definition and improved EDBSI. CE-TTE should be viewed as an additional imaging technique that is available to help assess patients with ACHD, especially those with nondiagnostic images.