Quantitative assessment of primary mitral regurgitation using left ventricular volumes obtained with new automated three-dimensional transthoracic echocardiographic software: A comparison with 3-Tesla cardiac magnetic resonance.

BACKGROUND: Quantitative assessment of primary mitral regurgitation (MR) using left ventricular (LV) volumes obtained with three-dimensional transthoracic echocardiography (3D TTE) recently showed encouraging results. Nevertheless, 3D TTE is not incorporated into everyday practice, as current LV chamber quantification software products are time consuming. AIMS: To investigate the accuracy and reproducibility of new automated fast 3D TTE software (HeartModelA.I.; Philips Healthcare, Andover, MA, USA) for the quantification of LV volumes and MR severity in patients with isolated degenerative primary MR; and to compare regurgitant volume (RV) obtained with 3D TTE with a cardiac magnetic resonance (CMR) reference. METHODS: Fifty-three patients (37 men; mean age 64±12 years) with at least mild primary isolated MR, and having comprehensive 3D TTE and CMR studies within 24h, were eligible for inclusion. MR RV was calculated using the proximal isovelocity surface area (PISA) method and the volumetric method (total LV stroke volume minus aortic stroke volume) with either CMR or 3D TTE. RESULTS: Inter- and intraobserver reproducibility of 3D TTE was excellent (coefficient of variation≤10%) for LV volumes. MR RV was similar using CMR and 3D TTE (57±23mL vs 56±28mL; P=0.22), but was significantly higher using the PISA method (69±30mL; P<0.05 compared with CMR and 3D TTE). The PISA method consistently overestimated MR RV compared with CMR (bias 12±21mL), while no significant bias was found between 3D TTE and CMR (bias 2±14mL). Concordance between echocardiography and CMR was higher using 3D TTE MR grading (intraclass correlation coefficient [ICC]=0.89) than with PISA MR grading (ICC=0.78). Complete agreement with CMR grading was more frequent with 3D TTE than with the PISA method (76% vs 63%). CONCLUSION: 3D TTE RV assessment using the new generation of automated software correlates well with CMR in patients with isolated degenerative primary MR.

Performance of new automated transthoracic three-dimensional echocardiographic software for left ventricular volumes and function assessment in routine clinical practice: Comparison with 3 Tesla cardiac magnetic resonance.

BACKGROUND: Three-dimensional (3D) transthoracic echocardiography (TTE) is superior to two-dimensional Simpson's method for assessment of left ventricular (LV) volumes and LV ejection fraction (LVEF). Nevertheless, 3D TTE is not incorporated into everyday practice, as current LV chamber quantification software products are time-consuming. AIMS: To evaluate the feasibility, accuracy and reproducibility of new fully automated fast 3D TTE software (HeartModelA.I.; Philips Healthcare, Andover, MA, USA) for quantification of LV volumes and LVEF in routine practice; to compare the 3D LV volumes and LVEF obtained with a cardiac magnetic resonance (CMR) reference; and to optimize automated default border settings with CMR as reference. METHODS: Sixty-three consecutive patients, who had comprehensive 3D TTE and CMR examinations within 24hours, were eligible for inclusion. Nine patients (14%) were excluded because of insufficient echogenicity in the 3D TTE. Thus, 54 patients (40 men; mean age 63±13 years) were prospectively included into the study. RESULTS: The inter- and intraobserver reproducibilities of 3D TTE were excellent (coefficient of variation<10%) for end-diastolic volume (EDV), end-systolic volume (ESV) and LVEF. Despite a slight underestimation of EDV using 3D TTE compared with CMR (bias=-22±34mL; P<0.0001), a significant correlation was found between the two measurements (r=0.93; P=0.0001). Enlarging default border detection settings leads to frequent volume overestimation in the general population, but improved agreement with CMR in patients with LVEF≤50%. Correlations between 3D TTE and CMR for ESV and LVEF were excellent (r=0.93 and r=0.91, respectively; P<0.0001). CONCLUSION: 3D TTE using new-generation fully automated software is a feasible, fast, reproducible and accurate imaging modality for LV volumetric quantification in routine practice. Optimization of border detection settings may increase agreement with CMR for EDV assessment in dilated ventricles.

Usefulness of 3-Tesla cardiac magnetic resonance imaging in the assessment of aortic stenosis severity in routine clinical practice.

BACKGROUND: Recently, 1.5-Tesla cardiac magnetic resonance imaging (CMR) was reported to provide a reliable alternative to transthoracic echocardiography (TTE) for the quantification of aortic stenosis (AS) severity. Few data are available using higher magnetic field strength MRI systems in this context. AIMS: To evaluate the feasibility and reproducibility of the assessment of aortic valve area (AVA) using 3-Tesla CMR in routine clinical practice, and to assess concordance between TTE and CMR for the estimation of AS severity. METHODS: Ninety-one consecutive patients (60 men; mean age 74±10years) with known AS documented by TTE were included prospectively in the study. RESULTS: All patients underwent comprehensive TTE and CMR examination, including AVA estimation using the TTE continuity equation (0.81±0.18cm2), direct CMR planimetry (CMRp) (0.90±0.22cm2) and CMR using Hakki's formula (CMRhk), a simplified Gorlin formula (0.70±0.19cm2). Although significant agreement with TTE was found for CMRp (r=0.72) and CMRhk (r=0.66), CMRp slightly overestimated (bias=0.11±0.18cm2) and CMRhk slightly underestimated (bias=-0.11±0.17cm2) AVA compared with TTE. Inter- and intraobserver reproducibilities of CMR measurements were excellent (r=0.72 and r=0.74 for CMRp and r=0.88 and r=0.92 for peak aortic velocity, respectively). CONCLUSION: 3-Tesla CMR is a feasible, radiation-free, reproducible imaging modality for the estimation of severity of AS in routine practice, knowing that CMRp tends to overestimate AVA and CMRhk to underestimate AVA compared with TTE.