Evaluation of aortic regurgitation after transcatheter aortic valve implantation: aortic root angiography in comparison to cardiac magnetic resonance.

AIMS: Aortic regurgitation (AR) is common after transcatheter aortic valve implantation (TAVI). Intraprocedural assessment of AR relies on aortic root angiography. Cardiac magnetic resonance (CMR) phase-contrast mapping of the ascending aorta provides accurate AR quantification. This study evaluated the accuracy of AR grading by aortic root angiography after TAVI in comparison to CMR phase-contrast velocity mapping. METHODS AND RESULTS: In 69 patients with TAVI for severe aortic stenosis, post-procedural AR was determined by aortic root angiography with visual assessment according to the Sellers classification and by CMR using phase-contrast velocity mapping for analysis of AR volume and fraction. Spearman's correlation coefficient showed a moderate correlation between angiographic analysis of AR grade and CMR-derived AR volume (r=0.41; p<0.01) as well as AR fraction (r=0.42; p<0.01). There was significant overlap between the angiographic Sellers classes compared to CMR-derived AR fractions. Aortic root angiography with cut-off Sellers grade ≥2 had a sensitivity of 71% and a specificity of 98% to detect AR graded as moderate to severe or severe as defined by CMR. CONCLUSIONS: There is only a moderate correlation between aortic root angiography and CMR in the classification of AR severity after TAVI. Alternative imaging including multimodality imaging as well as haemodynamic analysis should therefore be considered for intraprocedural AR assessment and guidance of TAVI procedure in cases of uncertainty in AR grading.

Functional effect of new atrial septal defect after percutaneous mitral valve repair using the MitraClip device.

Percutaneous mitral valve repair using the MitraClip device has become a therapeutic alternative for high surgical risk patients with symptomatic mitral regurgitation. The procedure involves transseptal puncture and results in a new atrial septal defect (ASD) after withdrawal of the 22Fr guiding catheter. The functional effect of the new ASD is not defined. In 28 patients with symptomatic mitral regurgitation undergoing percutaneous mitral valve repair using the MitraClip device, 3-dimensional transesophageal echocardiography was used to measure by direct en face imaging the area of the new ASD. Analysis of the velocity-time integral (VTI) across the ASD after withdrawal of the guiding catheter allowed calculation of the shunt volume. Diastolic VTI of the mitral flow was determined before and after withdrawal of the guiding catheter to determine left ventricular inflow changes. Invasive left atrial pressure measurements were obtained during withdrawal of the guiding catheter. Regurgitant volume was reduced from 86±21 ml/beat before intervention to 43±22 ml/beat after intervention. The new ASD had an area of 0.19 cm2, 44% of the area of the 22Fr guiding catheter. Considering the VTI across the septal defect of 72±26 cm/s, the left-to-right atrial shunt volume was calculated to be 14±6 ml/beat. The diastolic forward flow across the mitral valve was reduced by 13±6 ml/beat immediately after withdrawal of the MitraClip guiding catheter. Mean left atrial pressure was reduced from 17±8 mm Hg with the guiding catheter still in the left atrium to 15±8 mm Hg after withdrawal of the guiding catheter. In conclusion, the creation of a new ASD as consequence of the large-diameter MitraClip guiding catheter results in volume and pressure relief of the left atrium. This contributes to the immediate hemodynamic changes implemented by the MitraClip procedure.

Two-year mortality after transcatheter aortic valve implantation versus medical therapy for high-surgical risk or inoperable aortic stenosis patients.

BACKGROUND AND AIM OF THE STUDY: Transcatheter aortic valve implantation (TAVI) has become a therapeutic option for the treatment of high-risk or inoperable patients with symptomatic severe aortic stenosis. The study aim was to compare the two-year mortality of high-risk or inoperable patients treated by TAVI compared to medical therapy, in a single-center setting. METHODS: A total of 135 consecutive patients (58 males, 77 females; mean age 80 +/- 6 years; logistic EuroSCORE 21 +/- 13%) who had undergone TAVI was compared to 135 patients (60 males, 75 females; mean age 79 +/- 3 years; logistic EuroSCORE 21 +/- 19%) who had undergone medical treatment before TAVI became available. The one- and two-year follow up mortalities were recorded for each group. In the TAVI group, the patient characteristics were analyzed for predictors of mortality. RESULTS: Sixteen patients (12%) in the TAVI group and 10 (7%) in the medically treated group died within 30 days of intervention or presentation (p = 0.303). At the one-year follow up, 28 TAVI patients (21%) and 69 medically treated patients (41%) died (p < 0.001). At the two-year follow up, 41 TAVI patients (30%) and 80 medically treated patients (59%) died (p < 0.001). Log-rank analysis demonstrated a significant survival benefit after TAVI compared to medical treatment during the total follow up period. Univariate predictors of death at the two-year follow up included medical therapy, logistic EuroSCORE, and pulmonary hypertension. Medical therapy remained the only independent predictor of two-year mortality in a multivariate analysis (OR 3.343; 95% CI 2.021-6.234, p < 0.001). CONCLUSION: In high-surgical risk or inoperable symptomatic aortic stenosis patients, the one- and two-year follow up mortalities of patients treated with TAVI was significantly lower than after medical therapy. Predictors of mortality, in addition to treatment strategy, were pulmonary hypertension and EuroSCORE.

Impact of a new conduction defect after transcatheter aortic valve implantation on left ventricular function.

OBJECTIVES: This study sought to evaluate the impact of new conduction defects after transcatheter aortic valve implantation (TAVI) on the evolution of left ventricular (LV) function during 1-year follow-up. BACKGROUND: New left bundle branch block (LBBB) or need for permanent pacing due to atrioventricular (AV) block are frequent after TAVI. METHODS: A total of 90 consecutive patients treated with TAVI and who had 12-month echocardiographic follow-up were included in the study. In 39 patients, a new conduction defect (new LBBB or need for permanent pacemaker activity.) persisted 1 month after TAVI. In 51 patients, no persistent new conduction defect was observed. Two-dimensional echocardiography using parasternal short-axis, apical 4-chamber, and apical 2-chamber views was performed before TAVI and at 1-year follow-up to determine LV volumes and ejection fraction based on Simpson's rule. Speckle-tracking echocardiography was applied using standard LV short-axis images to assess the effect of new conduction defects on time-to-peak radial strain of different LV segments as a parameter of LV dyssynchrony. RESULTS: New conduction defects resulted in marked heterogeneity in time-to-peak strain between the 6 analyzed short-axis segments. During 1-year follow-up after TAVI, there was a significant increase in left ventricular ejection fraction (LVEF) in patients without new LBBB (53 ± 11% pre TAVI to 59 ± 10% at follow-up; p < 0.001), whereas there was no change in LVEF in patients with a new conduction defect (52 ± 11% pre TAVI to 51 ± 12% at follow-up, p = 0.740). Change in LV end-systolic volume was also significantly different between patient groups (-1.0 ± 14.2 vs. -11.2 ± 15.7 ml, p = 0.042). New conduction defect and LVEF at baseline were independent predictors of reduced LVEF at 12-month follow-up after TAVI. CONCLUSIONS: LVEF improves after TAVI for treatment of severe aortic stenosis in patients without new conduction defects. In patients with a new conduction defect after TAVI, there is no improvement in LVEF at follow-up.

Analysis of procedural effects of percutaneous edge-to-edge mitral valve repair by 2D and 3D echocardiography.

BACKGROUND: Analysis of procedural effects in patients undergoing percutaneous mitral valve repair (PMVR) using the edge-to-edge technique is complex, and common methods to define mitral regurgitation severity based on 2-dimensional (2D) echocardiography are not validated for postprocedural double-orifice mitral valve. This study used 3D transesophageal echocardiography (TEE) to determine the functional and morphological effects of PMVR. METHODS AND RESULTS: In 39 high-risk surgical patients with moderate to severe functional mitral valve regurgitation, 3D TEE with and without color Doppler as well as 2D transthoracic and TEE was performed before and after PMVR (MitraClip device). Mitral valve regurgitant volume by color Doppler 3D TEE was determined as the product of vena contracta areas defined by direct planimetry and velocity time integral using continuous-wave Doppler. Regurgitant volume was reduced from 84.1±38.3 mL preintervention to 35.6±25.6 mL postintervention. Patients in whom vena contracta area could be reduced >50% had a smaller preprocedural mitral annulus area compared with patients with ≤50% reduction (11.9±3.9 versus 16.1±8.5 cm(2), respectively; P=0.036) and tended to have a smaller mitral annulus circumference (13.0±2.0 versus 14.8±4.1 cm, respectively; P=0.112). At 6 months follow-up, left atrial and left ventricular end-diastolic volumes were significantly more reduced in patients in whom regurgitant vena contracta area was reduced by >50% compared with those with less reduction (-11.4±5.2 versus -4.8±7.7%; P=0.005, and -11.0±7.2 versus -4.5±9.3%; P=0.028). The maximum diastolic mitral valve area decreased from 6.0±2.0 to 2.9±0.9 cm(2) (P<0.0001). CONCLUSIONS: Three dimensional TEE demonstrates significant reduction of regurgitant volume after PMVR. The unique visualization of the mitral valve by 3D TEE allows improved understanding of the morphological and functional changes induced by PMVR.

Incidence and predictors of left bundle branch block after transcatheter aortic valve implantation.

OBJECTIVE: The aim of this study was to evaluate the frequency and predictors of left bundle branch block (LBBB) after Transcatheter Aortic Valve Implantation (TAVI) using CoreValve and Edwards SAPIEN prosthesis. METHODS: 154 consecutive patients (53 male, mean age 81 ± 7 years) with severe symptomatic aortic stenosis underwent TAVI. Transfemoral AVI (CoreValve) was performed in 72 patients (47%). Transapical AVI (Edwards SAPIEN valve) was done with in n=82 patients (53%). Patient characteristics, valvular and left ventricular outflow tract geometry from pre- and postprocedural imaging (computed tomography, transesophageal echocardiography and callipered angiography) and procedural characteristics were evaluated to define predictors of new LBBB after TAVI. PATIENTS: Preprocedural LBBB was present in 15 patients (n=5 CoreValve, n=10 in Edwards SAPIEN). In 40 of 139 patients (29%) a new LBBB was observed after TAVI. The frequency of new LBBB was higher with CoreValve n=27 (38%) than with Edwards SAPIEN implantation n=13 (16%; p=0.006). Patients with new LBBB had larger valve implantation depth into the left ventricular outflow tract (9.0 ± 2.9 vs. 4.4 ± 2.5mm, p<0.001). In 18 of 40 patients (45%) the new LBBB was persistent at 30days. Predictors of new LBBB were prosthesis implantation depth into the left ventricular outflow tract (OR=1.185 95% CI 1.064-1.320 per additional mm implantation depth; p=0.002) and use of CoreValve prosthesis (OR=2.639 95% CI 1.314-5.813; p=0.007). CONCLUSION: TAVI is frequently associated with new LBBB. There is a higher frequency of persistent LBBB with the CoreValve system. Implantation depth is a critical factor for the development of new LBBB.

Thirty-day outcome after transcatheter aortic valve implantation compared with surgical valve replacement in patients with high-risk aortic stenosis: a matched comparison.

BACKGROUND: Transcatheter aortic valve implantation (TAVI) has become a therapeutic alternative to surgery for the treatment of severe aortic stenosis in high-surgical risk patients. The aim of this study was to compare 30-day mortality of high-risk patients treated by TAVI versus surgical aortic valve replacement. METHODS: A total of 175 patients (60 men; mean age, 80±6 years; Euroscore 21±13%) having undergone TAVI were compared with 175 matched patients (76 men; mean age, 79±3 years; Euroscore 17±9%), which have undergone conventional aortic valve replacement and were deemed to be high-risk patients by the cardiothoracic surgeons. Thirty-day mortality and major adverse events were recorded in both groups. Patients' characteristics were analyzed for predictors of mortality in the TAVI group. RESULTS: Twenty-one patients (12%) in the TAVI group and 13 patients (8%) in the surgical group died within 30 days of the procedure (P=0.165). Two patients (1%) in the TAVI group and one patient (0.5%) in the conventional surgery group had a major stroke (P=1.0). Seven patients (4%) in the TAVI group and 25 patients (14%) in the conventional surgery group required dialysis post procedure (P=0.0013). The average length of stay in the intensive care unit was lower in the TAVI group compared with the conventional surgical group (3.3±3.1 vs. 6.6±10.5 days; P<0.001). Age was the only independent predictor of mortality in the TAVI group (odds ratio=1.009; 95% confidence interval: 1.001-1.018 per additional year; P=0.0186) and in the total study population (odds ratio=1.007; 95% confidence interval: 1.001-1.013 per additional year; P=0.0186). CONCLUSION: In high-surgical risk patients, TAVI can be performed at a mortality risk comparable with conventional surgery with a reduced length of post interventional intensive care unit stay and less need for dialysis.

Comparison of two-dimensional and three-dimensional imaging techniques for measurement of aortic annulus diameters before transcatheter aortic valve implantation.

AIMS: Different two-dimensional (2D) and three-dimensional (3D) imaging techniques are used for procedure planning and selection of prosthesis size before transcatheter aortic valve implantation. This study sought to compare different 2D and 3D imaging techniques and determine the accuracy of 3D transoesophageal echocardiography (TEE) for accurate analysis of aortic annulus dimensions. METHODS: In 49 consecutive patients with severe aortic stenosis undergoing transcatheter aortic valve implantation angiography, 2D transthoracic echocardiography (TTE), 2D and 3D TEE, and dual-source CT (DSCT) were performed to determine aortic annulus diameters. TTE and 2D TEE provided only one diameter of the aortic annulus. Angiography, DSCT and 3D TEE allowed measurement of diameters in sagittal and coronal views. The distance between aortic annulus and left main coronary artery ostium was measured by angiography, DSCT and 3D TEE. RESULTS: Sagittal diameters determined by angiography, TTE, 2D TEE, 3D TEE and DSCT were smaller than coronal diameters determined by angiography, 3D TEE and DSCT. Coronal and sagittal diameters determined by 3D TEE were in high agreement with corresponding measurements by DSCT (23.60±1.89 vs 23.46±2.07 mm and 22.19±1.96 vs 22.27±2.01 mm, respectively; mean±SD). There was a high correlation between DSCT and 3D TEE for the definition of coronal and sagittal aortic annulus diameters (r=0.88, SEE=0.89 mm and r=0.77, SEE=1.26 mm, respectively). Correlation of 3D TEE (13.47±1.67 mm) and DSCT (13.64±1.82 mm) in the analysis of the distance between aortic annulus and left main coronary artery ostium was better (r=0.54, SEE=1.55 mm) than between angiography (14.85±3.84 mm) and DSCT (r=0.35, SEE=1.77 mm). CONCLUSIONS: 3D imaging techniques should be used to evaluate aortic annulus diameters, as 2D imaging techniques, providing only a sagittal view, underestimate them. 3D TEE provides measurements of aortic annulus diameters similar to those obtained by DSCT.

Impact of transcutaneous aortic valve implantation on myocardial deformation.

AIMS: To define the impact of transcutaneous aortic valve implantation (TAVI) using the CoreValve prosthesis on myocardial deformation in a serial echocardiographic study with analysis of strain and strain rate. METHODS: In 36 patients (83 ± 6 years; EuroScore: 26 ± 13%) with severe aortic stenosis scheduled for CoreValve implantation serial echocardiographic studies pre- and postintervention (within 1 month) were performed. Midparasternal short-axis and three apical views were acquired. Using customized computer software which allows automatic frame-by-frame tracking of acoustic markers during the heart cycle circumferential, radial, and longitudinal strain (CS, RS, and LS) and strain rate (CSR, RSR, and LSR) were calculated for each segment in a 16 segment model of the left ventricle. RESULTS: Longitudinal strain, systolic, and early diastolic longitudinal strain rate increased significantly within 1 month after TAVI (LS from -15.8 ± 3.6% to -17.6 ± 3.1%; P < 0.001; LSR(S) from -1.03 ± 0.21 s(-1) to -1.21 ± 0.19 s(-1); P < 0.001 and LSR (E) from -1.15 ± 0.42 s(-1) to 1.51 ± 0.44 s(-1); P < 0.001). Circumferential strain and strain rate values remained unchanged after CoreValve implantation. RS (29.1 ± 17.1 to 34.0 ± 15.8%; ns), RSR (S) (1.56 ± 0.69 to 1.91 ± 0.87 s(-1); ns) and RSR(E) (-1.56 ± 0.78 to -1.81 ± 0.82 s(-1); ns) increased only nonsignificantly after TAVI. Analysis of covariance showed only chronic kidney disease to have a relevant impact on early diastolic LSR (P = 0.01). CONCLUSIONS: Mainly longitudinal mechanics respond to unloading of the left ventricle after TAVI for severe aortic stenosis while radial and circumferential deformation is substantially unchanged. Pacemaker implantation or onset of left bundle brunch block after TAVI do not influence early myocardial deformation parameters.

Association of aortic valve calcification severity with the degree of aortic regurgitation after transcatheter aortic valve implantation.

BACKGROUND: This study sought to examine a possible relationship between the severity of aortic valve calcification (AVC), the distribution of AVC and the degree of aortic valve regurgitation (AR) after transcatheter aortic valve implantation (TAVI) for severe aortic stenosis (AS). METHODS: 57 patients (22 men, 81 ± 5 years) with symptomatic AS and with a logistic EuroSCORE of 24 ± 12 were included. 38 patients (67%) received a third (18F)-generation CoreValve® aortic valve prosthesis, in 19 patients (33%) an Edwards SAPIEN™ prosthesis was implanted. Prior to TAVI dual-source computed tomography for assessment of AVC was performed. To determine the distribution of AVC the percentage of the calcium load of the most severely calcified cusp was calculated. After TAVI the degree of AR was determined by angiography and echocardiography. The severity of AR after TAVI was related to the severity and distribution of AVC. RESULTS: There was no association between the distribution of AVC and the degree of paravalvular AR after TAVI as assessed by angiography (r = -0.02, p = 0.88). Agatston AVC scores were significantly higher in patients with AR grade ≥ 3 (5055 ± 1753, n = 3) than in patients with AR grade < 3 (1723 ± 967, p = 0.03, n = 54). Agatston AVC scores > 3000 were associated with a relevant paravalvular AR and showed a trend for increased need for second manoeuvres. There was a significant correlation between the severity of AVC and the degree of AR after AVR (r = 0.50, p < 0.001). CONCLUSION: Patients with severe AVC have an increased risk for a relevant AR after TAVI as well as a trend for increased need for additional procedures.