Comparative assessment of ascending aortic aneurysms in Marfan patients using ECG-gated computerized tomographic angiography versus trans-thoracic echocardiography.

BACKGROUND: Contrast-enhanced computed tomography (CT) is routinely used as a complementary technique to trans-thoracic echocardiography (TTE) for assessing thoracic aortic aneurysms (TAA). However different measures can be obtained on CT and there are no recommendations on which to use. The objective was to determine which CT measurements most closely match reference TTE measurements in Marfan patients with TAA. METHODS: TTE measurements were obtained using the leading edge-to-leading edge technique in end-diastole on the parasternal longitudinal view. ECG-gated CT measurements were obtained, using the inner-to-inner technique in end-diastole by double oblique reconstruction: on three-cavity view (3C), left ventricle-aorta view (LVAo), and strict transverse plane passing through the maximal diameter "cusp to commissure" and "cusp to cusp" for each cusp. CT and TTE were performed within one month. RESULTS: 44 Marfan patients (39 ± 19 years, 48% men) were included. Dilatation of the ascending aorta was maximal at the level of the sinuses (TTE diameters: mean 47.5 ± 5.3 mm). TTE diameters were similar to 3C, LVAo (mean differences: 2.2 and -0.1 mm, p=NS) and to the three "cusp to cusp" diameters (mean differences ranging from 0 to 1.1mm, p=NS), whereas "cusp to commissure" diameters were all statistically smaller than TTE (3.6 mm, 2.9 mm and 3.7 mm, p ≤ 0.01). CONCLUSIONS: Inner-to-inner "cusp to cusp" diameter measured on an ECG-gated CT should be used for comparison with 2D TTE aortic diameter at the level of the sinuses of Valsalva in patients with thoracic aortic aneurysms.

Comparison of semiquantitative and quantitative assessment of severity of aortic regurgitation: clinical implications.

BACKGROUND: Recent studies have emphasized the importance of quantitative assessment of the degree of aortic regurgitation (AR). However, semiquantitative methods have remained mainly used despite their unclear diagnostic value. The aim of this study was to define the sensitivity and specificity of semiquantitative methods compared with the proximal isovelocity surface area method as a reference for the diagnostic of severe AR. METHODS: The degree of AR was evaluated using the proximal isovelocity surface area method and four semiquantitative measurements (left ventricular cardiac output, pressure half-time, diastolic flow reversal, and vena contracta) in 224 patients with a wide range of AR severity. RESULTS: The mean effective regurgitant orifice area was 25 ± 14 mm(2) (range, 3-69 mm(2)), the mean regurgitant volume was 57 ± 31 mL (range, 9-183 mL), and 100 patients (44%) had severe AR (effective regurgitant orifice area ≥ 30 mm(2) or regurgitant volume ≥ 60 mL). Overall, semiquantitative methods had good specificity but poor sensitivity, except the vena contracta, which had good sensitivity and specificity. Sensitivity, specificity, and positive and negative predictive values of the recommended thresholds for severe AR of the four semiquantitative methods were 53%, 89%, 77%, and 73% for left ventricular cardiac output ≥ 10 L/min; 12%, 100%, 100%, and 52% for pressure half-time < 200 msec; 45%, 87%, 79%, and 60% for diastolic flow reversal ≥ 18 cm/sec; and 81%, 83%, 78%, and 85% for vena contracta ≥ 6 mm, respectively. CONCLUSIONS: For the assessment of AR severity, current thresholds appear specific but poorly sensitive, except for vena contracta, which provides good discriminative value. Semiquantitative methods should be integrated into the comprehensive evaluation of AR severity, but severe AR should not be excluded only on the basis of semiquantitative criteria. These results emphasize the need for the quantitative assessment of AR severity.

Multimodal assessment of the aortic annulus diameter: implications for transcatheter aortic valve implantation.

OBJECTIVES: We sought to compare 3 methods of measurements of the aortic annulus, transthoracic echocardiography (TTE), transesophageal echocardiography (TEE), and multislice computed tomography (MSCT), and to evaluate their potential clinical impact on transcatheter aortic valve implantation (TAVI) strategy. BACKGROUND: Exact measurement of the aortic annulus is critical for a patient's selection and successful implantation. METHODS: Annulus diameter was measured using TTE, TEE, and MSCT in 45 consecutive patients with severe aortic stenosis referred for TAVI. The TAVI strategy (decision to implant and choice of the prosthesis' size) was based on manufacturer's recommendations (Edwards-Sapien prosthesis, Edwards Lifesciences, Inc., Irvine, California). RESULTS: Correlations between methods were good but the difference between MSCT and TTE (1.22 +/- 1.3 mm) or TEE (1.52 +/- 1.1 mm) was larger than the difference between TTE and TEE (0.6 +/- 0.8 mm; p = 0.03 and p < 0.0001, respectively). Regarding TAVI strategy, agreement between TTE and TEE overall was good (kappa = 0.68), but TAVI strategy would have been different in 8 patients (17%). Agreement between MSCT and TTE or TEE was only modest (kappa = 0.28 and 0.27), and a decision based on MSCT measurements would have modified the TAVI strategy in a large number of patients (40% to 42%). Implantation, performed in 34 patients (76%) based on TEE measurements, was successful in all but 1 patient with grade 3/4 regurgitation. CONCLUSIONS: In patients referred for TAVI, measurements of the aortic annulus using TTE, TEE, and MSCT were close but not identical, and the method used has important potential clinical implications on TAVI strategy. In the absence of a gold standard, a strategy based on TEE measurements provided good clinical results.

Results of transfemoral or transapical aortic valve implantation following a uniform assessment in high-risk patients with aortic stenosis.

OBJECTIVES: We sought to describe the results of a strategy offering either transfemoral or transapical aortic valve implantation in high-risk patients with severe aortic stenosis. BACKGROUND: Results of transfemoral and transapical approaches have been reported separately, but rarely following a uniform assessment to select the procedure. METHODS: Of 160 consecutive patients at high risk or with contraindications to surgery, referred between October 2006 and November 2008, 75 were treated with transcatheter aortic valve implantation. The transfemoral approach was used as the first option and the transapical approach was chosen when contraindications to the former were present. The valve used was the Edwards Lifesciences SAPIEN prosthesis. RESULTS: Patients were age 82 +/- 8 years (mean +/- SD), in New York Heart Association functional classes III/IV, with predicted mean surgical mortalities of 26 +/- 13% using the European System for Cardiac Operative Risk Evaluation and 16 +/- 7% using the Society of Thoracic Surgeons Predicted Risk of Mortality. Fifty-one patients were treated via the transfemoral approach, and 24 via the transapical approach. The valve was implanted in 93% of the patients. Hospital mortality was 10%. Mean (+/- SD) 1-year survivals were 78 +/- 6% in the whole cohort, 81 +/- 7% in the transfemoral group, 74 +/- 9% in the transapical group (p = 0.22), and 60 +/- 10% in the first 25 patients versus 93 +/- 4% in the last 50 patients treated (p = 0.001). In multivariate analysis, early experience was the only significant predictor of late mortality. CONCLUSIONS: Being able to offer either transfemoral or transapical aortic valve implantation, within a uniform assessment, expands the scope of the treatment of aortic stenosis in high-risk patients and provides satisfactory results at 1 year in this population. The results are strongly influenced by experience.