Early Regression of Left Ventricular Mass Associated with Diastolic Improvement after Transcatheter Aortic Valve Implantation

Predicting Left Ventricular Adverse Remodeling After Transcatheter Aortic Valve Replacement: A Radiomics Approach

RATIONALE AND OBJECTIVES

To develop a radiomics model based on cardiac computed tomography (CT) for predicting left ventricular adverse remodeling (LVAR) in patients with severe aortic stenosis (AS) who underwent transcatheter aortic valve replacement (TAVR).

MATERIALS AND METHODS

Patients with severe AS who underwent TAVR from January 2019 to December 2022 were recruited. The cohort was divided into adverse remodeling group and non-adverse remodeling group based on LVAR occurrence, and further randomly divided into a training set and a validation set at an 8:2 ratio. Left ventricular radiomics features were extracted from cardiac CT. The least absolute shrinkage and selection operator regression was utilized to select the most relevant radiomics features and clinical features. The radiomics features were used to construct the Radscore, which was then combined with the selected clinical features to build a nomogram. The predictive performance of the models was evaluated using the area under the curve (AUC), while the clinical value of the models was assessed using calibration curves and decision curve analysis.

RESULTS

A total of 273 patients were finally enrolled, including 71 with adverse remodeling and 202 with non-adverse remodeling. 12 radiomics features and five clinical features were extracted to construct the radiomics model, clinical model, and nomogram, respectively. The radiomics model outperformed the clinical model (training AUC: 0.799 vs. 0.760; validation AUC: 0.766 vs. 0.755). The nomogram showed highest accuracy (training AUC: 0.859, validation AUC: 0.837) and was deemed most clinically valuable by decision curve analysis.

CONCLUSION

The cardiac CT-based radiomics features could predict LVAR after TAVR in patients with severe AS.

Diastolic Dysfunction and Health Status Outcomes After Transcatheter Aortic Valve Replacement

Background

Baseline left ventricular diastolic dysfunction (LVDD) is associated with poor health status in patients with severe aortic stenosis undergoing transcatheter aortic valve replacement (TAVR), but health status improvement after TAVR appears similar across all grades of LVDD. Here, we aim to examine the relationship between changes in LVDD severity and health status outcomes following TAVR.

Methods

Patients who underwent TAVR and had evaluable LVDD at both baseline and 1 year in the PARTNER (Placement of Aortic Transcatheter Valves) 2 SAPIEN 3 registries and PARTNER 3 trial were analyzed. LVDD grade was evaluated using echocardiography core lab data and an adapted definition of American Society of Echocardiography guidelines. Health status was assessed using the Kansas City Cardiomyopathy Questionnaire Overall Summary (KCCQ-OS) score. The association between ΔLVDD severity and ΔKCCQ-OS was examined using linear regression models adjusted for baseline KCCQ-OS.

Results

Of 1100 patients, 724 (65.8%), 283 (25.7%), and 93 (8.5%) had grade 0/1, 2, and 3 LVDD at baseline, respectively. At 1 year, LVDD severity was unchanged in 790 (71.8%) patients, improved in 189 (17.2%), and worsened in 121 (11.0%). Among 376 patients with baseline grade 2 or 3 LVDD, 50.3% had improvement in LVDD. In the overall cohort, KCCQ-OS score improved by 21.9 points at 1 year. There was a statistically significant association between change in LVDD severity (improved, unchanged, and worsened) and ΔKCCQ-OS at 1 year (p = 0.007).

Conclusions

Change in LVDD grade was associated with change in health status 1 year following TAVR.

Left ventricular reverse remodeling after transcatheter aortic valve implantation in patients with low-flow low-gradient aortic stenosis

OBJECTIVES

Left ventricular reverse remodeling (LVRR) is associated with improved outcome in patients with heart failure. Factors associated with and predictive of LVRR in patients with low-flow low-gradient aortic stenosis (LFLG AS) after transcatheter aortic valve implantation (TAVI) and its impact on outcome were assessed.

METHODS

Pre- and postprocedural left ventricular (LV) function and volume were investigated in 219 patients with LFLG. LVRR was defined as an absolute increase of ≥10% in LV ejection fraction (LVEF) and reduction of ≥15% in LV end-systolic volume (LVESV). The primary endpoint was the combination of all-cause mortality and rehospitalization for heart failure.

RESULTS

The mean LVEF was 35.0 ± 10.0%, with a stroke volume index (SVI) of 25.9 ± 6.0 mL/m2 and LVESV of 94.04 ± 46.0 mL. At a median of 5.2 months (interquartile range, 2.7-8.1 months), 77.2% (n = 169) of the patients showed echocardiographic evidence of LVRR. A multivariate model revealed three independent factors for LVRR after TAVI: SVI of <25 mL/m2 (hazard ratio [HR], 2.31; 95% confidence interval [CI], 1.08-3.58; p < 0.01), LVEF of <30% (HR, 2.76; 95% CI, 1.53-2.91; p < 0.01), and valvulo-arterial impedance (Zva) of <5 mmHg/mL/m2 (HR, 5.36; 95% CI, 1.80-15.98; p < 0.01). Patients without evidence of LVRR showed a significantly higher incidence of the 1-year combined endpoint (32 [64.0%] vs. 75 [44.4%], p < 0.01).

CONCLUSIONS

The majority of patients with LFLG AS show LVRR after TAVI, which is associated with favorable outcomes. An SVI of <25 mL/m2, LVEF of <30%, and Zva < 5mmHg/mL/m2 represent predictors of LVRR.

Noninvasive Hemodynamic Evaluation Following TAVI for Severe Aortic Stenosis

Background Various hemodynamic changes occur following transcatheter aortic valve implantation (TAVI) that may impact therapeutic decisions. NICaS is a noninvasive bioimpedance monitoring system aimed at hemodynamic assessment. We used the NICaS system in patients with severe aortic stenosis (AS) to evaluate short-term hemodynamic changes after TAVI. Methods and Results We performed hemodynamic analysis using NICaS on 97 patients with severe AS who underwent TAVI using either self-expandable (68%) or balloon-expandable (32%) valves. Patients were more often women (54%) and had multiple comorbidities including hypertension (83%), coronary artery disease (46%), and diabetes (37%). NICaS was performed at several time points-before TAVI, soon after TAVI, at hospital discharge, and during follow-up. Compared with baseline NICaS measurements, we observed a significant increase in systolic blood pressure and total peripheral resistance (systolic blood pressure 132±21 mm Hg at baseline versus 147±23 mm Hg after TAVI, P<0.001; total peripheral resistance 1751±512 versus 2084±762 dynes*s/cm⁵, respectively, P<0.001) concurrent with a decrease in cardiac output and stroke volume (cardiac output 4.2±1.5 versus 3.9±1.3 L/min, P=0.037; stroke volume 61.4±14.8 versus 56.2±15.9 mL, P=0.001) in the immediate post-TAVI period. At follow-up (median 59 days [interquartile range, 40.5-91]) these measurements returned to values that were not different from the baseline. A significant improvement in echocardiography-based left ventricular ejection fraction was observed from baseline to follow-up (55.6%±11.6% to 59.4%±9.4%, P<0.001). Conclusions Unique short-term adaptive hemodynamic changes were observed using NICaS in patients with AS soon after TAVI. Noninvasive hemodynamic evaluation immediately following TAVI may contribute to the understanding of complex hemodynamic changes and merits favorable consideration.

The Evolution of Pulmonary Hypertension and Its Prognostic Implications Post-TAVI-Single Center Experience

Background and Objectives: Since the first transcatheter aortic valve implantation (TAVI) procedure was performed in 2002, advances in technology and refinement of the method have led to its widespread use in patients with severe aortic stenosis (AS) and high surgical risk. We aim to identify the impact of TAVI on the clinical and functional status of patients with severe AS at the one-month follow-up and to identify potential predictors associated with the evolution of pulmonary hypertension (PH) in this category of patients. Materials and Methods: We conducted a prospective study which included 86 patients diagnosed with severe AS undergoing TAVI treatment. We analyzed demographics, clinical and echocardiographic parameters associated with AS and PH both at enrolment and at the 30-day follow-up. Results: In our study, the decrease of EUROSCORE II score (p < 0.001), improvement of angina (p < 0.001) and fatigue (p < 0.001) as clinical benefits as well as a reduction in NYHA functional class in patients with heart failure (p < 0.001) are prognostic predictors with statistical value. Regression of left ventricular hypertrophy (p = 0.001), increase in the left ventricle ejection fraction (p = 0.007) and improvement of diastolic dysfunction (p < 0.001) are echocardiographic parameters with a prognostic role in patients with severe AS undergoing TAVI. The pulmonary artery acceleration time (PAAT) (p < 0.001), tricuspid annular plane systolic excursion (TAPSE) (p = 0.020), pulmonary arterial systolic pressure (PASP) (p < 0.001) and the TAPSE/PASP ratio (p < 0.001) are statistically significant echocardiographic parameters in our study that assess both PH and its associated prognosis in patients undergoing TAVI. Conclusions: PAAT, TAPSE, PASP and the TAPSE/PASP ratio are independent predictors that allow the assessment of PH and its prognostic implications post-TAVI.

Incidence, Predictors, and Prognostic Impact of Immediate Improvement in Left Ventricular Systolic Function After Transcatheter Aortic Valve Implantation

Immediate improvement in left ventricular ejection fraction (LVEF) following transcatheter aortic valve implantation (TAVI) is common; however, data on the pattern and prognostic value of this improvement are limited. To evaluate the incidence, predictors, and clinical impact of immediate improvement in LVEF, we studied 694 consecutive patient who had underwent successful TAVI for severe aortic stenosis (AS) between March 2010 and December 2019. We defined immediate improvement of LVEF as an absolute increase of ≥5% in LVEF at post-procedure echocardiogram. The primary outcome was major adverse cardiac or cerebrovascular event (MACCE), defined as a composite of death from cardiovascular cause, myocardial infarction, stroke, or rehospitalization from cardiovascular cause. Among them, 160 patients showed immediate improvement in LVEF. The independent predictors of immediate LVEF improvement were absence of hypertension and baseline significant aortic regurgitation, and greater baseline LV mass index. Immediate improvement in LVEF was significantly associated with a lower risk of MACCE (adjusted hazard ratio, 0.48; 95% confidence interval, 0.28-0.81; p = 0.01). In conclusion, approximately one-fourth of patients with severe AS who underwent TAVI showed immediate improvement in LVEF during index hospitalization. Immediate LVEF recovery was associated with a lower risk of MACCE during follow-up.

Subclinical leaflet thrombosis is associated with impaired reverse remodelling after transcatheter aortic valve implantation

AIMS

Cardiac CT is increasingly applied for planning and follow-up of transcatheter aortic valve implantation (TAVI). However, there are no data available on reverse remodelling after TAVI assessed by CT. Therefore, we aimed to evaluate the predictors and the prognostic value of left ventricular (LV) reverse remodelling following TAVI using CT angiography.

METHODS AND RESULTS

We investigated 117 patients with severe, symptomatic aortic stenosis (AS) who underwent CT scanning before and after TAVI procedure with a mean follow-up time of 2.6 years after TAVI. We found a significant reduction in LV mass (LVM) and LVM indexed to body surface area comparing pre- vs. post-TAVI images: 180.5 ± 53.0 vs. 137.1 ± 44.8 g and 99.7 ± 25.4 vs. 75.4 ± 19.9 g/m2, respectively, both P < 0.001. Subclinical leaflet thrombosis (SLT) was detected in 25.6% (30/117) patients. More than 20% reduction in LVM was defined as reverse remodelling and was detected in 62.4% (73/117) of the patients. SLT, change in mean pressure gradient on echocardiography and prior myocardial infarction was independently associated with LV reverse remodelling after adjusting for age, gender, and traditional risk factors (hypertension, body mass index, diabetes mellitus, and hyperlipidaemia): OR = 0.27, P = 0.022 for SLT and OR = 0.22, P = 0.006 for prior myocardial infarction, OR = 1.51, P = 0.004 for 10 mmHg change in mean pressure gradient. Reverse remodelling was independently associated with favourable outcomes (HR = 0.23; P = 0.019).

CONCLUSION

TAVI resulted in a significant LVM regression on CT. The presence of SLT showed an inverse association with LV reverse remodelling and thus it may hinder the beneficial LV structural changes. Reverse remodelling was associated with improved long-term prognosis.

Left ventricular speckle tracking echocardiographic evaluation before and after TAVI

AIMS

To assess left ventricular (LV) function before and after transcatheter aortic valve implantation (TAVI) using conventional echocardiographic parameters and global longitudinal LV strain (GLS) and compare outcomes between Edwards S3 and Evolut R valves.

METHODS AND RESULTS

Data were collected for consecutive patients undergoing TAVI at Hammersmith hospital between 2015 and 2018. Of the 303 patients, those with coronary artery disease and atrial fibrillation were excluded leading to a total of 85 patients, which constituted our study group. The mean follow-up was 49 ± 39 days. In total, 60% of patients were treated with Edwards S3 and 40% Evolut R. TAVI resulted in an early improvement of GLS (-13.96 to -15.25%, P = 0.01) but not ejection fraction (EF) (47.6 to 50.1%, P = 0.09). LV mass also improved, especially in patients with marked baseline LV hypertrophy (P < 0.001). There were no appreciable differences of LV function improvement and overall LV remodelling after TAVI between the two types of valves used (P = 0.14).

CONCLUSIONS

TAVI results in reverse remodelling and improvement of GLS, especially in patients with impaired baseline LV function. There were no differences in the extent of LV function improvement between Edwards S3 and Evolut R valves but there was a greater incidence of aortic regurgitation with Evolut R.

Assessment of left ventricular diastolic function after Transcatheter aortic valve implantation in aortic stenosis patients by echocardiographic according to different guidelines

Background

To evaluate the detailed dynamic change of left ventricular diastolic function (LVDF) by echocardiography in aortic stenosis (AS) patients receiving transcatheter aortic valve implantation (TAVI) and compare LVDF classification according to 2009 ASE/EAE and 2016 ASE/EACVI recommendations.

Methods

Thirty-five AS patients receiving TAVI underwent echocardiography the day before operation (PRE), on the third day (3D), in the first-month (1 M) and the six-month (6 M) after TAVI. LVDF was analyzed using 2D and doppler imaging to get parameters including E/A, E/e’, isovolumic relaxation time (IVRT), deceleration time, LA area, LA volume index (LAVI) and systolic tricuspid regurgitation velocity (TR). LVDF classification was evaluated four times for each patient according to 2009 and 2016 recommendations respectively and the results were compared.

Results

The decrease of IVRT and TR occurred immediately post surgery up to 1-month. Improvement of E/e’ occurred late from 3-day to 1-month. LA area and LAVI decreased continuously shortly after operation till 6-month. Forty-four percent (62/140) by 2009 recommendations were reclassified with different grades when using 2016 guidelines. Comparing PRE and 6 M, with 2009 guidelines, 19 patients improved 1 grade, 8 patients improved 2 grades; with 2016 guidelines, 9 patients improved 1 grade, 13 patients improved 2 grades, 1 patient improved 3 grades.

Conclusions

The conventional 2D echocardiography could effectively reflect variation process of LVDF in AS patients after TAVI. For LVDD classification, obvious differences resulted by the 2009 and updated recommendations were found, and more patients can be regarded as benefiting from TAVI by 2016.

recommendations.

Impact of Baseline Left Ventricular Diastolic Dysfunction in Patients With Severe Aortic Stenosis Undergoing Transcatheter Aortic Valve Implantation

We sought to assess the impact of diastolic dysfunction (DD) grade, as per the 2016 American Society of Echocardiography/European Association of Cardiovascular Imaging guidelines, on survival of patients with severe aortic stenosis (AS) who underwent transcatheter aortic valve implantation (TAVI). We included consecutive patients with severe AS who underwent TAVI in our institution. DD grading was determined retrospectively according to the 2016 ASE DD guidelines and categorized to grade I-III and indeterminate grade I-II DD. Comparison of 1-year survival according to DD grade was performed by Kaplan-Meier analysis, and evaluation of DD at 1 year was performed in a subset of patients. Among 606 TAVI patients, 394 (65%) had sufficient data for DD grading. Seventy-seven (20%) had grade I DD, 191 (48%) had grade II, 60 (15%) had grade III, and 66 (17%) had an indeterminate grade between I and II. Baseline characteristics indicate higher rates of atrial fibrillation, brain natriuretic peptide level, pulmonary artery systolic pressure, and indexed left ventricular mass as DD grade increases (all p ≤0.01). In conclusion, comparison of 1-year survival revealed a higher rate of mortality in patients with grade III DD that remained statistically significant following adjustment in a multivariate Cox proportional hazard model. DD grade after TAVI improved in patients with grades II and III. Severe AS patients with grade III DD have higher risk for 1-year mortality after TAVI compared with milder degrees of DD. Further research is warranted to explore a potential benefit for aortic valve therapy at an earlier stage of the disease process.

Immediate and Evolutionary Recovery of Left Ventricular Diastolic Function after Transcatheter Aortic Valve Replacement: Comparison with Surgery

PURPOSE

We aimed to compare the effect of transcatheter aortic valve replacement (TAVR) and surgical aortic valve replacement (sAVR) on recovery of left ventricular (LV) diastolic function and afterload through serial echocardiographic examinations in patients with symptomatic high-risk severe aortic stenosis during early follow-up.

MATERIALS AND METHODS

We included 38 patients undergoing TAVR (mean age, 80±6 years; male:female=18:20) and 27 patients undergoing sAVR (mean age, 78±3 years; male:female=12:15). We compared changes in the LV diastolic function and afterload before, immediately after, and 3 months after the procedure using serial transthoracic echocardiography.

RESULTS

Immediately after the procedure, 16 (42%) and 3 (11%) patients in the TAVR and sAVR groups, respectively, showed rapid improvement in diastolic filling patterns. E wave to e' ratio (E/e') and right ventricular systolic pressure (RVSP) decreased significantly in the TAVR group (E/e': TAVR, from 24.6±12.9 to 20±9.5, p=0.048 vs. sAVR, from 21.5±9.4 to 20.64±6.4, p=0.361; RVSP: TAVR, 38.4±17.2 vs. 34±12.4, p=0.032 vs. sAVR, 32.2±11.7 vs. 30±6.8, p=0.27). After 3 months, diastolic grade distribution, E/e', and RVSP were similar. Valvuloarterial impedance significantly decreased immediately after the procedure in both groups (TAVR, from 5.1±1.4 to 3.1±1.0 vs. sAVR, from 4.5±1.5 to 3.1±0.8 mm Hg · mL⁻¹ · m⁻², p=0.001), but after 3 months, decreases were greater in the sAVR group (from 3.1±0.8 to 2.2±1.5 mm Hg · mL⁻¹ · m⁻², p=0.093).

CONCLUSION

LV diastolic function improved more rapidly and earlier in patients treatment with TAVR than in patients treated with sAVR. These results might explicate the remarkable clinical improvement in improvements in advanced diastolic dysfunction immediately after the TAVR procedure than sAVR.

Significance of echocardiographic evaluation for transcatheter aortic valve implantation

Transcatheter aortic valve implantation (TAVI) is widely accepted as an alternative to surgical aortic valve replacement (SAVR) for the treatment of severe aortic stenosis (AS). Existing scientific evidence demonstrates that TAVI is superior to SAVR, and it is expected that indications for the clinical applications of TAVI will be expanded in the future. Echocardiography plays a key role in perioperative assessment of patients undergoing TAVI. Preprocedural echocardiographic evaluation is important to determine the severity of AS in addition to patients' anatomical suitability for TAVI. Furthermore, echocardiography is essential for intraoperative guidance, assessment of complications, postoperative evaluation, and prognostic prediction. Inaccurate echocardiographic measurements and evaluation can lead to less-than-optimal/inappropriate treatment strategies in patients with AS. Therefore, a thorough understanding of the limitations of echocardiographic evaluation is important. This review summarizes the role of echocardiographic evaluation in patients undergoing TAVI.

Impact of diastolic dysfunction on long-term mortality and quality of life after transcatheter aortic valve replacement

BACKGROUND

There is conflicting data as to whether diastolic dysfunction (DD) affects the prognosis of patients with aortic stenosis (AS) undergoing transcatheter aortic valve replacement (TAVR).

METHODS

Consecutive patients undergoing TAVR underwent assessment of DD with preoperative echocardiography and NT-pro BNP. Long-term survival was ascertained every 6 months by clinic visits or phone. DD was graded according to the new American Society of Echocardiography recommendations. Health status was assessed at baseline and 30 days post-procedure using the KCCQ-12 questionnaire. Long-term survival was displayed using Kaplan-Meier curves according to NT-pro BNP levels and DD grades.

RESULTS

We included 222 patients, mean age 78 (±8) years, median STS score 4 (interquartile range = 3-7), median follow-up time 385 days (IQR = 180-640). DD was absent in 25, Grade I in 13, Grade II in 74, Grade III in 24, and indeterminate in 86 patients. Advanced (Grades II-III) DD was associated with higher pre-procedural NT-pro BNP levels (p < .001), worse quality of life (p < .001) but similar surgical risk (p = .43). Advanced and indeterminate DD were associated with increased long-term mortality (25-28% vs. 5%, p = .02) and elevated NT-pro BNP levels (26.4% vs. 9.8%, p = .05). Improvements in quality of life measures were seen in all DD groups (median change in KCCQ score no or Grade I DD:14 [3-21] vs. Grades II-III DD: 15 [16-26; p = .37]).

CONCLUSION

Preoperative NT-pro BNP levels and echocardiographic indices of indeterminate or advanced DD are associated with increased long-term mortality after TAVR but similar improvements in quality of life.

Short-term changes of blood pressure and aortic stiffness in older patients after transcatheter aortic valve implantation

Background

Both aortic valve stenosis and aortic stiffness are moderators of arterio ventricular coupling and independent predictors of cardiovascular morbidity and mortality. Studies on the effect of transcatheter aortic valve implantation (TAVI) on aortic functional properties are limited. We performed a study to investigate the possible short-term changes in aortic stiffness and other aortic functional properties after TAVI in older patients.

Methods

TAVI Care&Cure is an observational ongoing study including consecutive patients undergoing a TAVI procedure. Central and peripheral hemodynamic measurements were measured non invasively 1 day before (T-1) and 1 day after (T+1) TAVI using a validated oscillometric method using a brachial cuff (Mobil-O-Graph).

Results

40 patients were included. Mean aortic valve area at baseline was 0.76±0.24 cm². Indices of severity of aortic valve stenosis improved significantly. Systolic blood pressure (SBP) dropped by 8.5%, from 130.3±22.9 mmHg to 119.5±15.8 mmHg (p=0.005). Diastolic blood pressure (DBP) dropped by 13.1% from 74.8±14.5 mmHg to 65.0±11.3 mmHg (p<0.001). The arterial pulse wave velocity (aPWV) decreased from 12.05±1.99 m/s to 11.6±1.56 m/s (p=0.006). Patients with high aPWV at baseline showed a significantly larger reduction in SBP in comparison to patients with low aPWV: – 20.3 mmHg (−14.1%) vs – 3.1 mmHg (−2.6%), respectively (p=0.033). The same trend was found for the DBP: −16.2 (−20.4%) vs −4.5 mmHg (−6.3%) for high vs low aPWV at baseline (p=0.037).

Conclusion

We found short-term changes in blood pressure and aortic stiffness after TAVI. The amplitude of the changes was the largest in patients with elevated aortic stiffness at baseline.

Dysregulation of proangiogeneic factors in pressure-overload left-ventricular hypertrophy results in inadequate capillary growth

Background:

Pressure-overload left-ventricular hypertrophy (LVH) is an increasingly prevalent pathological condition of the myocardial muscle and an independent risk factor for a variety of cardiac diseases. We investigated changes in expression levels of proangiogeneic genes in a small animal model of LVH.

Methods:

Myocardial hypertrophy was induced by transaortic constriction (TAC) in C57BL/6 mice and compared with sham-operated controls. The myocardial expression levels of vascular endothelial growth factor (VEGF), its receptors (KDR and FLT-1), stromal-cell-derived factor 1 (SDF1) and the transcription factors hypoxia-inducible factor-1 and 2 (HIF1 and HIF2) were analyzed by quantitative polymerase chain reaction over the course of 25 weeks. Histological sections were stained for caveolin-1 to visualize endothelial cells and determine the capillary density. The left-ventricular morphology and function were assessed weekly by electrocardiogram-gated magnetic resonance imaging.

Results:

The heart weight of TAC animals increased significantly from week 4 to 25 (p = 0.005) compared with sham-treated animals. At 1 day after TAC, the expression of VEGF and SDF1 also increased, but was downregulated again after 1 week. The expression of HIF2 was significantly downregulated after 1 week and remained at a lower level in the subsequent weeks. The expression level of FLT-1 was also significantly decreased 1 week after TAC. HIF-1 and KDR showed similar changes compared with sham-operated animals. However, the expression levels of HIF1 after 4 and 8 weeks were significantly decreased compared with day 1. KDR changes were significantly decreased after 1, 2, 4, 8 and 25 weeks compared with week 3. After 4 weeks post-TAC, the size of the capillary vessels increased (p = 0.005) while the capillary density itself decreased (TAC: 2143 ± 293 /mm²versus sham: 2531 ± 321 /mm²; p = 0.021). Starting from week 4, the left-ventricular ejection fraction decreased compared with controls (p = 0.049).

Conclusions:

The decrease in capillary density in the hypertrophic myocardium appears to be linked to the dysregulation in the expression of proangiogeneic factors. The results suggest that overcoming this dysregulation may lead to reconstitution of capillary density in the hypertrophic heart, and thus be beneficial for cardiac function and survival.

Valve hemodynamic performance and myocardial strain after implantation of a third-generation, balloon-expandable, transcatheter aortic valve

BACKGROUND

Left ventricular (LV) mechanics are impaired in patients with severe aortic stenosis (AS); however, transcatheter aortic valve implantation (TAVI) may positively affect LV mechanics. Assessed herein is the performance of the SAPIEN 3 transcatheter heart valve (THV) and the effect of TAVI on LV function recovery, as assessed by global longitudinal strain (GLS).

METHODS

A subset of patients from the SOURCE 3 registry (n = 276) from 16 European centers received SAPIEN 3 balloon-expandable THV. Echocardiography was performed at baseline, postprocedure, and at 1 year, including assessment of GLS using standard two-dimensional images, and was analyzed in a core laboratory. Paired analyses between baseline and discharge, baseline and at 1 year were conducted.

RESULTS

Hemodynamic parameters were improved after TAVI and sustained to 1 year. At 1 year, the rate of moderate to severe paravalvular leaks (PVL), and moderate to severe mitral and tricuspid regurgitations were 1.8%, 1.7%, and 8.0%, respectively. The discharge GLS (-15.6 ± 5.1; p = 0.004; n = 149) improved significantly from baseline (-15.1 ± 4.8) following TAVI. This improvement was sustained at 1 year compared with baseline (-17.0 ± 4.6, p < 0.001; n = 100). Conversely, LV ejection fraction (LVEF) did not significantly change following TAVI (p = 0.47).

CONCLUSIONS

Following TAVI with a third-generation THV, valve performances were good at 1 year with low PVL rate. The LV mechanics improved immediately after the procedure and were maintained at 1 year. These findings demonstrate the benefit of TAVI on LV mechanics, and suggests that GLS may be superior to LVEF in assessing this benefit. Clinicaltrial.gov number: NCT02698956.

Left Ventricular Diastolic Dysfunction and Transcatheter Aortic Valve Replacement Outcomes: A Review

Aortic stenosis (AS) is the most common valvular disease that can lead to increased afterload, left ventricular (LV) remodeling, and myocardial fibrosis. We reviewed the literature addressing the impact of transcatheter aortic valve replacement (TAVR) on LV remodeling and patients' outcomes by elimination of AS-related high afterload. TAVR reduces afterload and improves LV remodeling recovery. However, myocardial fibrosis may not completely reverse after the TAVR. The LV diastolic dysfunction (LVDD) induced by AS is an independent predictor of post-TAVR mortality, and mortality increases with severity of LVDD. The impact of diastolic dysfunction on patient outcomes emerges at 30 days but continues to persist during mid-term follow-up. Based on severity of the baseline LVDD, some patients may tolerate post-TAVR aortic regurgitation (AR), but even minimal post-TAVR AR in patients with severe baseline LVDD can have an additive negative impact on survival. It is crucial to consider TAVR prior to development of advanced LVDD. Appropriate device selection and deployment technique are important in improvement of TAVR outcomes via elimination of AR.

Cardiovascular magnetic resonance assessment of 1st generation CoreValve and 2nd generation Lotus valves

OBJECTIVES

We sought to compare using serial CMR, the quantity of AR and associated valve hemodynamics, following the first-generation CoreValve (Medtronic, Minneapolis, MN) and the second-generation Lotus valve (Boston Scientific, Natick, MA).

BACKGROUND

Aortic regurgitation (AR) following Transcatheter Aortic Valve Replacement (TAVR) confers a worse prognosis and can be accurately quantified using cardiovascular magnetic resonance (CMR). Second generation valves have been specifically designed to reduce paravalvular AR and improve clinical outcomes.

METHODS

Fifty-one patients (79.0 ± 7.7 years, 57% male) were recruited and imaged at three time points: immediately pre- and post-TAVR, and at 6 months.

RESULTS

CMR-derived AR fraction immediately post-TAVR was greater in the CoreValve compared to Lotus group (11.7 ± 8.4 vs. 4.3 ± 3.4%, P = 0.001), as was the frequency of ≥moderate AR (9/24 (37.5%) versus 0/27, P < 0.001). However, at 6 months AR fraction had improved significantly in the CoreValve group such that the two valve designs were comparable (6.4 ± 5.0 vs 5.6 ± 5.3%, P = 0.623), with no patient in either group having ≥moderate AR. The residual peak pressure gradient immediately following TAVR was significantly lower with CoreValve compared to Lotus (14.1 ± 5.6 vs 25.4 ± 11.6 mmHg, P = 0.001), but again by 6 months the two valve designs were comparable (16.5 ± 9.4 vs 19.7 ± 10.5 mmHg, P = 0.332). There was no difference in the degree of LV reverse remodeling between the two valves at 6 months.

CONCLUSION

Immediately post-TAVR, there was significantly less AR but a higher residual peak pressure gradient with the Lotus valve compared to CoreValve. However, at 6 months both devices had comparable valve hemodynamics and LV reverse remodeling.

Medium and long-term prognosis of transcatheter aortic valve implantation from the perspective of left ventricular diastolic function

BACKGROUND

The effects of left ventricular (LV) diastolic function are well known in cardiac surgery, but unclear in transcatheter aortic valve implantation (TAVI). The objective of this study was to exam- ine the association of preoperative LV diastolic function with medium to long-term outcomes of TAVI.

METHODS

Eighty patients who underwent TAVI were classified into grades I, II and III based on pre- operative LV diastolic function. Findings related to cardiovascular outcomes after TAVI were extracted retrospectively from clinical and echocardiographic data and relationships with diastolic function were examined.

RESULTS

The average follow-up was 529 days (interquartile range {IQR] 358-741 days). Cardiovascu- lar events occurred in 17 cases, including 6 deaths, and were significantly associated with Euro II score (p = 0.043), albumin level (p = 0.026), coronary artery disease (CAD) (p = 0.017), and diastolic func- tion (p < 0.001). The 360-day event-free rates were 89.5%, 89.5% and 37.5% for grades I, II and III (p = 0.00013). Median event-free survival (EFS) in grade III cases was 180 days. In a Cox propor- tional hazard model, LV diastolic dysfunction (hazard ratio [HR] 3.99, 95% confidence interval [CI] 1.35-11.80, p = 0.012) and low albumin (HR 4.73, 95% CI 1.42-15.80, p = 0.012) were significant independent predictors of reduced EFS.

CONCLUSIONS

Medium to long-term outcomes of TAVI were poorer in patients with deteriorated LV diastolic function, and outcomes in grade III cases were significantly worse than those in grade I and II cases. Preoperative LV diastolic function may be useful in prediction of outcomes after TAVI.

The role of echocardiography in transcatheter aortic valve implantation

Transcatheter aortic valve implantation (TAVI) is an effective and less invasive treatment for the increasing population of individuals with severe aortic stenosis (AS). Echocardiography is crucial in the assessment of AS patients from pre- to post-procedure. Transthoracic echocardiography (TTE) may be used to assess patient suitability for TAVI, as well as evaluate the severity of AS, the aortic valve complex, aortic valve morphology, mitral regurgitation (MR), and left ventricular function. Transesophageal echocardiography (TEE) is usually used as an intra-procedural monitoring tool to provide feedback during the procedure, to assess prosthetic valve function, and to detect complications rapidly before and after balloon aortic valvuloplasty (BAV) or transcatheter heart valve (THV) deployment. In this review, the role of echocardiography in the pre-, intra-, and post-TAVI procedure periods is described in detail.

The effect of transcatheter aortic valve implantation on Tp-e interval, Tp-e/QT and Tp-e/QTc ratios, and Tp-e dispersion in patients with severe aortic stenosis

Background

In this study, we aimed to investigate the effect of transcatheter aortic valve implantation using two types of bioprosthetic valves on novel ventricular repolarization markers including Tp-e, Tp-e/QT and Tpe/QTc ratios, and Tp-ed.

Methods

A total of 61 patients (17 males, 44 females; mean age 78.6±6.5 years; range 55 to 89 years) who underwent transcatheter aortic valve implantation with either a Medtronic CoreValve (n=40) or an Edwards SAPIEN XT valve (n=21) were retrospectively analyzed. The electrocardiographic parameters and left ventricular mass index were calculated prior to the procedure, on postoperative Day 1, and at three months after the procedure.

Results

The Tp-e interval, Tp-e/QT and Tp-e/QTc ratios, Tp-ed, and left ventricular mass index significantly reduced at three months of the procedure, compared to baseline values (p<0.01, for all). Similar findings were observed for QT, QTc, and QT dispersion (p<0.01, for all). These changes were independent from the types of bioprosthetic valves used. Before the procedure, the left ventricular mass index was positively correlated with the Tp-e (r=0.350, p=0.007), Tp-e/QT (r=0.314, p=0.015) and Tp-e/QTc ratios (r=0.285, p=0.029). In the multivariate analysis, Tp-e interval was found to be independently associated with the left ventricular mass index (b=0.350, p=0.007).

Conclusion

In the present study, the Tp-e interval, Tp-e/QT and Tp-e/QTc ratios, Tp-ed, and left ventricular mass index significantly reduced at three months after transcatheter aortic valve implantation indicating reverse left ventricular remodeling. The effects of two types of bioprosthetic valves on ventricular repolarization markers and left ventricular mass index were similar.

Predictors of 1-Year Mortality After Transcatheter Aortic Valve Implantation in Patients With and Without Advanced Chronic Kidney Disease

Advanced chronic kidney disease (CKD) is an independent predictor of mortality in patients undergoing transcatheter aortic valve implantation (TAVI). We aimed to identify predictors of 1-year mortality in patients after TAVI stratified by the presence or absence of advanced CKD (defined as estimated glomerular filtration rate ≤30 ml/min/1.73 m² or permanent renal replacement therapy). Patients (n = 1204) from 10 centers in Europe, Japan, and Israel were included: 464 with and 740 without advanced CKD. Advanced CKD was associated with a 2-fold increase in the adjusted risk of 1-year all-cause death (p <0.001), and a 1.9-fold increase in cardiovascular death (p = 0.016). Interaction-term analysis was used to identify and compare independent predictors of 1-year mortality in both groups. Impaired left ventricular ejection fraction and poor functional class were predictive of death in the advanced CKD group (odds ratio [OR] 2.27, p = 0.002 and OR 3.87, p = 0.003, respectively) but not in patients without advanced CKD (p for interaction = 0.035 and 0.039, respectively), whereas bleeding was a predictor of mortality in the nonadvanced CKD group (OR 3.2, p = 0.005) but not in advanced CKD (p for interaction = 0.006). Atrial fibrillation was associated with a 2.2-fold increase (p = 0.032) in the risk of cardiovascular death in the advanced CKD group but not in the absence of advanced CKD (p for interaction = 0.022). In conclusion, the coexistence of advanced CKD and either reduced left ventricular ejection fraction or poor functional class has an incremental effect on the risk of death after TAVI. In contrast, bleeding had a greater effect on risk of death in patients without advanced CKD.

The Impact of Transcatheter Aortic Valve Implantation and Surgical Aortic Valve Replacement on Left Ventricular Remodeling

Transcatheter aortic valve implantation (TAVI) appears to be equivalent to surgical aortic valve replacement (SAVR) with regard to clinical end points in high-risk and intermediate risk patients. Major landmark trials, such as Placement of Aortic Transcatheter Valves (PARTNER) trials 1 and 2 and US CoreValve show similar hemodynamic responses and left ventricular remodeling after both procedures. Real-life nonrandomized studies, however, suggest that TAVI may result in a somewhat better hemodynamic response and, therefore, a more favorable left ventricular remodeling than after SAVR for the first few years of follow-up. Further, there are fewer cases of prosthesis patient mismatch and more cases of paravalvular leak and conduction system abnormalities that affect the left ventricular remodeling process with TAVI than with SAVR. Overall, TAVI may be considered superior to SAVR in high-risk patients whose clinical outcome depends on a favorable remodeling process.

Calcific Aortic Valve Disease: Part 2-Morphomechanical Abnormalities, Gene Reexpression, and Gender Effects on Ventricular Hypertrophy and Its Reversibility

In part 1, we considered cytomolecular mechanisms underlying calcific aortic valve disease (CAVD), hemodynamics, and adaptive feedbacks controlling pathological left ventricular hypertrophy provoked by ensuing aortic valvular stenosis (AVS). In part 2, we survey diverse signal transduction pathways that precede cellular/molecular mechanisms controlling hypertrophic gene expression by activation of specific transcription factors that induce sarcomere replication in-parallel. Such signaling pathways represent potential targets for therapeutic intervention and prevention of decompensation/failure. Hypertrophy provoking signals, in the form of dynamic stresses and ligand/effector molecules that bind to specific receptors to initiate the hypertrophy, are transcribed across the sarcolemma by several second messengers. They comprise intricate feedback mechanisms involving gene network cascades, specific signaling molecules encompassing G protein-coupled receptors and mechanotransducers, and myocardial stresses. Future multidisciplinary studies will characterize the adaptive/maladaptive nature of the AVS-induced hypertrophy, its gender- and individual patient-dependent peculiarities, and its response to surgical/medical interventions. They will herald more effective, precision medicine treatments.

Echocardiographic determinants of LV functional improvement after transcatheter aortic valve replacement

BACKGROUND

Transcatheter aortic valve replacement (TAVR) is an established therapy in high-risk patients with severe aortic stenosis. Among patients with reduced left ventricular ejection fraction (LVEF), it is unclear which patients will derive maximal benefit from TAVR.

METHODS

Clinical and echocardiographic data of patients with severe aortic stenosis and low LVEF (≤50%) who underwent TAVR at a single institution during 2009-2013 were retrospectively analyzed. Patients were divided into 2 groups post-TAVR based on improved LV function (Group A = ΔLVEF ≥ 10%) versus persistent LV dysfunction (Group B = ΔLVEF<10%). Echocardiographic parameters were assessed for their association with LVEF change post-TAVR. Kaplan-Meier analysis was performed to generate survival estimates.

RESULTS

Of 382 patients who underwent TAVR, 60 patients had low LVEF, LV function failed to improve ≥10% in 50% of patients following the procedure (Group B). At baseline echocardiograms, Group B had higher LVEF, stroke volume (SV), SV index; and lower E, E/E', and estimated pulmonary arterial systolic pressure (PASP) compared to Group A. Higher mortality was found in Group B compared to the Group A (p = 0.003) with a significantly shorter survival (Group A = 3.3 ± 0.1 years vs Group B = 2.7 ± 0.2 years, p = 0.003). One-year event free survival was 53.3% in Group B compared to 93.3% in Group A, with a stable trend over ensuing years (5-year survival; 53.3% versus 90.0%, p = 0.003).

CONCLUSIONS

In patients undergoing TAVR with depressed LV function, those who failed to improve were more likely to have relatively higher LVEF, SV, and SVI; and lower E, E/E', and PASP at baseline. Mortality rates were found to be higher in persistent LV dysfunction group. © 2015 Wiley Periodicals, Inc.

Myocardial hypertrophy and its role in heart failure with preserved ejection fraction

Left ventricular hypertrophy (LVH) is the most common myocardial structural abnormality associated with heart failure with preserved ejection fraction (HFpEF). LVH is driven by neurohumoral activation, increased mechanical load, and cytokines associated with arterial hypertension, chronic kidney disease, diabetes, and other comorbidities. Here we discuss the experimental and clinical evidence that links LVH to diastolic dysfunction and qualifies LVH as one diagnostic marker for HFpEF. Mechanisms leading to diastolic dysfunction in LVH are incompletely understood, but may include extracellular matrix changes, vascular dysfunction, as well as altered cardiomyocyte mechano-elastical properties. Beating cardiomyocytes from HFpEF patients have not yet been studied, but we and others have shown increased Ca(2+) turnover and impaired relaxation in cardiomyocytes from hypertrophied hearts. Structural myocardial remodeling can lead to heterogeneity in regional myocardial contractile function, which contributes to diastolic dysfunction in HFpEF. In the clinical setting of patients with compound comorbidities, diastolic dysfunction may occur independently of LVH. This may be one explanation why current approaches to reduce LVH have not been effective to improve symptoms and prognosis in HFpEF. Exercise training, on the other hand, in clinical trials improved exercise tolerance and diastolic function, but did not reduce LVH. Thus current clinical evidence does not support regression of LVH as a surrogate marker for (short-term) improvement of HFpEF.

The impact of transcatheter aortic valve implantation on left ventricular performance and wall thickness - single-centre experience

INTRODUCTION

Transcatheter aortic valve implantation (TAVI) is a treatment alternative for the elderly population with severe symptomatic aortic stenosis (AS) at high risk for surgical aortic valve replacement (SAVR).

AIM

To assess the impact of TAVI on echocardiographic parameters of left ventricular (LV) performance and wall thickness in patients subjected to the procedure in a single-centre between 2009 and 2013.

MATERIAL AND METHODS

The initial group consisted of 170 consecutive patients with severe AS unsuitable for SAVR. Logistic European System for Cardiac Operative Risk Evaluation (EuroSCORE) was 21.73 ±12.42% and mean age was 79.9 ±7.5 years.

RESULTS

The TAVI was performed in 167 (98.2%) patients. Mean aortic gradient decreased significantly more rapidly after the procedure (from 58.6 ±16.7 mm Hg to 11.9 ±4.9 mm Hg, p < 0.001). The LV ejection fraction (LVEF) significantly increased in both short-term and long-term follow-up (57 ±14% vs. 59 ±13%, p < 0.001 and 56 ±14% vs. 60 ±12%, p < 0.001, respectively). Significant regression of interventricular septum diameter at end-diastole (IVSDD) and end-diastolic posterior wall thickness (EDPWth) was noted in early (15.0 ±2.4 mm vs. 14.5 ±2.3 mm, p < 0.001 and 12.7 ±2.1 mm vs. 12.4 ±1.9 mm, p < 0.028, respectively) and late post-TAVI period (15.1 ±2.5 mm to 14.3 ±2.5 mm, p < 0.001 and 12.8 ±2.0 mm to 12.4 ±1.9 mm, p < 0.007, respectively). Significant paravalvular leak (PL) was noted in 21 (13.1%) patients immediately after TAVI and in 13 (9.6%) patients in follow-up (p < 0.001). Moderate or severe mitral regurgitation (msMR) was seen in 24 (14.9%) patients from the initial group and in 19 (11.8%) patients after TAVI (p < 0.001).

CONCLUSIONS

The TAVI had an immediate beneficial effect on LVEF, LV walls thickness, and the incidence of msMR. The results of the procedure are comparable with those described in other centres.

Early regression of severe left ventricular hypertrophy after transcatheter aortic valve replacement is associated with decreased hospitalizations

OBJECTIVES

This study sought to examine the relationship between left ventricular mass (LVM) regression and clinical outcomes after transcatheter aortic valve replacement (TAVR).

BACKGROUND

LVM regression after valve replacement for aortic stenosis is assumed to be a favorable effect of LV unloading, but its relationship to improved clinical outcomes is unclear.

METHODS

Of 2,115 patients with symptomatic aortic stenosis at high surgical risk receiving TAVR in the PARTNER (Placement of Aortic Transcatheter Valves) randomized trial or continued access registry, 690 had both severe LV hypertrophy (left ventricular mass index [LVMi] ≥ 149 g/m(2) men, ≥ 122 g/m(2) women) at baseline and an LVMi measurement at 30-day post-TAVR follow-up. Clinical outcomes were compared for patients with greater than versus lesser than median percentage change in LVMi between baseline and 30 days using Cox proportional hazard models to evaluate event rates from 30 to 365 days.

RESULTS

Compared with patients with lesser regression, patients with greater LVMi regression had a similar rate of all-cause mortality (14.1% vs. 14.3%, p = 0.99), but a lower rate of rehospitalization (9.5% vs. 18.5%, hazard ratio [HR]: 0.50, 95% confidence interval [CI]: 0.32 to 0.78; p = 0.002) and a lower rate of rehospitalization specifically for heart failure (7.3% vs. 13.6%, p = 0.01). The association with a lower rate of rehospitalization was consistent across subgroups and remained significant after multivariable adjustment (HR: 0.53, 95% CI: 0.34 to 0.84; p = 0.007). Patients with greater LVMi regression had lower B-type natriuretic peptide (p = 0.002) and a trend toward better quality of life (p = 0.06) at 1-year follow-up than did those with lesser regression.

CONCLUSIONS

In high-risk patients with severe aortic stenosis and severe LV hypertrophy undergoing TAVR, those with greater early LVM regression had one-half the rate of rehospitalization over the subsequent year compared to those with lesser regression.

Influence of aortic regurgitation after TAVI on left ventricular filling pattern

BACKGROUND

Paravalvular aortic regurgitation after transcatheter aortic valve implantation is associated with a hemodynamic deterioration and a poor outcome. We aim to determine the early hemodynamic effect of paravalvular aortic regurgitation in relation with the change in the left ventricle filling pattern and to assess their clinical outcome.

MATERIAL AND METHODS

Eighty-two consecutive patients referred for transcatheter aortic valve implantation were included. Patients were classified according to the change in the left ventricular filling pattern, and significant paravalvular aortic regurgitation (grade ≥ 2) was reported. Follow-up and incidence of death and hospitalization for heart failure were reported.

RESULTS

Sixteen patients (19·5%) presented a worsening of left ventricular filling pattern. The incidence of significant paravalvular aortic regurgitation was higher in the group with a worsening of left ventricular filling pattern (56·3% vs. 19·7%; P = 0·009). In the multivariate analysis, the only variable significantly associated with the worsening of left ventricular filling pattern was the significant paravalvular aortic regurgitation (OR 4·84; 95% CI 1·23 - 19·1; P = 0·024). During the follow-up (642·5 days), there was a higher incidence of the endpoint of death or hospitalization for heart failure in the group with a worsening of left ventricular filling pattern (62·5% vs. 31·8%; P = 0·042) and a lower event-free survival rate (long rank test = 0·013).

CONCLUSIONS

The presence of a significant paravalvular aortic regurgitation is associated with a worsening in parameters of diastolic function. This finding should alert the cardiologist as patients with a worsening of left ventricular filling pattern present a higher incidence of paravalvular aortic regurgitation and a less favourable outcome.

Paravalvular regurgitation after transcatheter aortic valve replacement with the Edwards sapien valve in the PARTNER trial: characterizing patients and impact on outcomes

AIM

The impact of paravalvular regurgitation (PVR) following transcatheter aortic valve replacement (TAVR) remains uncertain. In this analysis, we sought to evaluate the impact of varying degrees of PVR on both mortality and changes in ventricular geometry and function.

METHODS AND RESULTS

Clinical and echocardiographic outcomes of patients who underwent TAVR from the randomized cohorts and continued access registries in the PARTNER trial were analysed after stratifying by severity of post-implant PVR, which was graded as none/trace in 52.9% (n = 1288), mild in 38.0% (n = 925), and moderate/severe in 9.1% (n = 221). There were significant differences in baseline clinical and echocardiographic characteristics. After TAVR, all the patients demonstrated increase in left ventricular (LV) function and reduction in the LV mass index, although the magnitude of mass regression was lower in the moderate/severe PVR group. The 30-day mortality (3.1 vs. 3.4 vs. 4.5%, P = 0.56) and stroke (3.4 vs. 3.7 vs. 2.3%, P = 0.59) were similar in all groups (none/trace, mild, and moderate/severe). At 1 year, there was increased all-cause mortality (15.9 vs. 22.2 vs. 35.1%, P < 0.0001), cardiac mortality (6.1 vs. 7.4% vs. 16.3%, P < 0.0001) and re-hospitalization (14.4 vs. 23.0 vs. 31.3%, P < 0.0001) with worsening PVR. A multivariable analysis indicated that the presence of moderate/severe PVR (HR: 2.18, 95% CI: 1.57-3.02, P < 0.0001) or mild PVR (HR: 1.37, 95% CI: 1.14-1.90, P = 0.012) was associated with higher late mortality.

CONCLUSION

Differences in baseline characteristics in patients with increasing severities of PVR may increase the risk of this complication. Despite these differences, multivariable analysis demonstrated that both mild and moderate/severe PVR predicted higher 1-year mortality.

Effects of transcatheter aortic valve implantation on ascending aorta wall elastic properties: Tissue Doppler imaging and strain Doppler echocardiography study

BACKGROUND

Aortic elastic properties are determinants of left ventricular function by means of ventriculo-arterial coupling and indicators of cardiovascular risk. Aortic valve stenosis surgical replacement temporary reduces aortic function damaging vasa vasorum, while transcatheter aortic valve implantation (TAVI) does not influence it in the short term. We studied aortic distensibility, stiffness, M-mode strain and tissue strain after 6 and 12 months from TAVI.

METHODS

We enrolled 15 patients with symptomatic severe aortic stenosis who underwent CoreValve prosthesis (Medtronic, Minneapolis, MN) implantation. Everyone had blood pressure measurement and echocardiography registration before TAVI and after 6 and 12 months.

RESULTS

After TAVI NYHA class (p = 0.016), peak and mean aortic valve gradients (p < 0.001 for both) improved. Aortic distensibility increased (p = 0.032 in the first 6 months, p = 0.005 in the second 6 months, and p = 0.003 from baseline to 12 months), as well as stiffness decreased (p = 0.034; 0.090; 0.001), M-mode strain and tissue strain ameliorated (p = 0.041; 0.004; 0.004; and p = 0.013; 0.002; 0.001, respectively), tissue Doppler imaging improved (S' wave: p = 0.289; 0.347; 0.018. E' wave: p = 0.018; 0.113; 0.007. A' wave: p = 0.002; 0.532; 0.001). Moreover, some left ventricular parameters improved at 6 months, such as ejection fraction (from 49 ± 16 to 57 ± 11%; p = 0.044) and diastolic interventricular septum thickness (from 14 ± 2 to 12 ± 2 mm; p = 0.010). Even systolic pulmonary artery pressure (p = 0.019) and left diastolic dysfunction grade ameliorated (p = 0.042).

CONCLUSIONS

For the first time we demonstrated that aortic elastic properties improve at 6 and 12 months after TAVI, thus influencing ventriculo-arterial coupling and ameliorating left ventricular function.

A critical review of hemodynamic changes and left ventricular remodeling after surgical aortic valve replacement and percutaneous aortic valve replacement

The introduction of transcatheter aortic valve replacement (TAVR) in clinical practice has widened options for symptomatic patients at high surgical risk; however, it is not known whether TAVR has equivalent or prolonged benefits in terms of left ventricular (LV) remodeling.

METHODS

To explore the relative hemodynamic benefits and postoperative LV remodeling associated with TAVR and surgical aortic valve replacement (SAVR), we performed a critical review of the available literature. A total of 67 studies were included in this systematic review.

RESULTS

There is at least equivalent if not slightly superior hemodynamic performance of TAVR over SAVR, and TAVR showed lower prosthesis-patient mismatch compared with SAVR. However, LV mass appears to regress to a greater degree after SAVR compared with TAVR. Aortic regurgitation, paravalvular in particular, is more common after TAVR than SAVR, although it is rarely more than moderate in severity. Improvements in diastolic function and mitral regurgitation are reported in only a handful of studies each and could not be compared across prosthesis types.

CONCLUSIONS

The published data support the hemodynamic comparability of SAVR and TAVR, with the higher incidence of prosthesis-patient mismatch in SAVR offset by higher incidence of paravalvular leak in TAVR. These results highlight the need for further studies focusing on hemodynamic changes after valve therapy.

Left ventricular functional recovery and remodeling in low-flow low-gradient severe aortic stenosis after transcatheter aortic valve implantation

BACKGROUND

Speckle-tracking-derived global longitudinal strain (GLS) is a more sensitive method of detecting left ventricular (LV) functional recovery after transcatheter aortic valve implantation (TAVI) in patients with severe aortic stenosis. However, it remains unknown whether LV function improves in patients with low-flow, low-gradient severe aortic stenosis (LFLGSAS) after TAVI. The aim of the present was to evaluate LV functional recovery and remodeling after TAVI in patients with LFLGSAS.

METHODS

Sixty-eight patients (57% men; mean age, 79.1 ± 7.1 years) with LFLGSAS treated with TAVI were evaluated. LV function and remodeling were investigated before TAVI and at 6 and 12 months after TAVI. All echocardiographic data were prospectively collected, and GLS was retrospectively analyzed.

RESULTS

Among patients with LFLGSAS, 35 (52%) had low LV ejection fraction (LVEF) (<50%), and 33 (48%) had preserved LVEF (≥50%). The low-LVEF group had significantly more impaired GLS than the group with preserved LVEF (-8.3 ± 2.6% vs -13.3 ± 3.5%, P < .001). LV systolic function improved after TAVI in both groups. Although in the group of patients with low LVEF, all functional parameters improved, in the group of patients with preserved LVEF, only strain-derived parameters significantly improved. There were significant decreases in absolute LV wall thickness and relative wall thickness and a trend toward decreased LV mass index in both LVEF groups. LV volumes decreased significantly in those with low LVEF but not in those with preserved LVEF. Baseline GLS but not LVEF group was independently associated to GLS improvement at 12 months after TAVI.

CONCLUSIONS

Patients with LFLGSAS with low and preserved LVEF had a significant improvement in LV function after TAVI, as assessed by GLS. Absolute and relative LV wall thickness decreased in both groups of patients, but only those with low LVEF had reductions in LV volumes.

Hemodynamic outcomes of transcatheter aortic valve implantation with the CoreValve system: an early assessment

BACKGROUND AND AIMS

Transcatheter aortic valve implantation (TAVI) is an established method for the treatment of high-risk patients with aortic stenosis (AS). The beneficial effects of TAVI in cardiac hemodynamics have been described in recent studies, but those investigations were mostly performed after an interval of more than 6 months following aortic valve implantation. The aim of this study is to investigate the acute and short-term alterations in hemodynamic conditions using the echocardiography outcomes in patients undergoing TAVI.

METHODS AND RESULTS

A total of 60 patients (26 males, 34 females; age 84·7 ± 5·8) who underwent TAVI with CoreValve system were included in the study. Echocardiography was performed before hospital discharge and at 3 months follow-up. As expected, TAVI was associated with an immediate significant improvement in aortic valve area (AVA) (from 0·64 ± 0·16 cm(2) to 1·67 ± 0·41 cm(2) , P-value<0·001) and mean gradient (from 51·9 ± 15·4 mmHg to 8·8 ± 3·8 mmHg, P-value<0·001). At 3-month follow-up, systolic LV function was augmented (EF: 50 ± 14% to 54 ± 11%, P-value = 0·024). Left ventricle (LV) mass and left atrium (LA) volume were significantly reduced (LV mass index from 126·5 ± 30·5 g m(-2) to 102·4 ± 32·4 g m(-2) ; LA index from 42·9 ± 17·3 ml m(-2) to 33·6 ± 10·6 ml m(-2) ; P-value<0·001 for both). Furthermore, a decrement in systolic pulmonary artery pressure (SPAP) from 47·5 ± 13·5 mmHg to 42·5 ± 11·2 mmHg, P-value = 0·02 was also observed. Despite the high incidence of paravalvular regurgitation (PVR) (80%), most of the patients presented mild or trace PVR and no significant progress of the regurgitation grade was seen after 3 months.

CONCLUSION

This study demonstrates that the beneficial effects of TAVI in cardiac function and hemodynamics occur already after a short period following aortic valve implantation.

Long-term prognostic value and serial changes of plasma N-terminal prohormone B-type natriuretic peptide in patients undergoing transcatheter aortic valve implantation

Little is known about the usefulness of evaluating cardiac neurohormones in patients undergoing transcatheter aortic valve implantation (TAVI). The objectives of this study were to evaluate the baseline values and serial changes of N-terminal prohormone B-type natriuretic peptide (NT-proBNP) after TAVI, its related factors, and prognostic value. A total of 333 consecutive patients were included, and baseline, procedural, and follow-up (median 20 months, interquartile range 9 to 36) data were prospectively collected. Systematic NT-proBNP measurements were performed at baseline, hospital discharge, 1, 6, and 12 months, and yearly thereafter. Baseline NT-proBNP values were elevated in 86% of the patients (median 1,692 pg/ml); lower left ventricular ejection fraction and stroke volume index, greater left ventricular mass, and renal dysfunction were associated with greater baseline values (p <0.01 for all). Higher NT-proBNP levels were independently associated with increased long-term overall and cardiovascular mortalities (p <0.001 for both), with a baseline cut-off level of ∼2,000 pg/ml best predicting worse outcomes (p <0.001). At 6- to 12-month follow-up, NT-proBNP levels had decreased (p <0.001) by 23% and remained stable up to 4-year follow-up. In 39% of the patients, however, there was a lack of NT-proBNP improvement, mainly related to preprocedural chronic atrial fibrillation, lower mean transaortic gradient, and moderate-to-severe mitral regurgitation (p <0.01 for all). In conclusion, most patients undergoing TAVI presented high NT-proBNP levels, and a lack of improvement was observed in >1/3 of the patients after TAVI. Also, higher NT-proBNP levels predicted greater overall and cardiac mortalities at a median follow-up of 2 years. These findings support the implementation of NT-proBNP measurements for the clinical decision-making process and follow-up of patients undergoing TAVI.

Predictors of improvement in diastolic function after transcatheter aortic valve implantation

BACKGROUND

Aortic stenosis is associated with concentric left ventricle (LV) hypertrophy or remodeling resulting in impaired diastolic function and elevated left-sided filling pressure. We investigated the changes in LV geometry and LV filling hemodynamics, giving emphasis to parameters associated with changes in diastolic function after transcatheter aortic valve implantation (TAVI).

METHODS

Comprehensive diastolic assessment was performed before and six months after TAVI in 70 patients with severe aortic stenosis. Patients with any degree of mitral stenosis or >mild left-sided valvular regurgitation were excluded.

RESULTS

In the entire cohort six months after TAVI, LV end-diastolic diameter increased (44.1 ± 6 versus 45 ± 6 mm, P = 0.02), whereas LV mass and relative wall thickness (RWT) decreased (270.1 ± 76 versus 245.1 ± 75 g and 0.53 ± 0.15 versus 0.46 ± 0.1, respectively; P < 0.0001 for both). Lateral e' increased (5.8 ± 2 versus 6.6 ± 3 cm/s, P = 0.03) and left atrium (LA) volume, E/e' ratio, and systolic pulmonary pressure decreased (88.1 ± 30 versus 80 ± 28 cc, 18 ± 7.8 versus 16.3 ± 5.5, and 42.7 ± 14.9 versus 38.7 ± 12 mmHg, respectively; P < 0.05 for all), suggesting reduction in LA pressure. The improvement in LA volume and E/e' was almost exclusively seen in patients with LV hypertrophy before TAVI (P < 0.05 both), as opposed to patients with concentric remodeling.

CONCLUSIONS

In our preliminary study, TAVI resulted in LV and LA reverse remodeling, and improved LV relaxation and LA filling pressure in patients with severe aortic stenosis and concentric hypertrophy. Patients with concentric remodeling at baseline seem to have limited improvement in LV diastolic function and filling pressure following TAVI, but larger clinical trials would be required to conclude if they have no improvement at all.

Parallel improvement of left ventricular geometry and filling pressure after transcatheter aortic valve implantation in high risk aortic stenosis: comparison with major prosthetic surgery by standard echo Doppler evaluation

Purpose

The effect of Transcatheter Aortic Valve Implantation (TAVI) on left ventricular (LV) geometry and function was compared to traditional aortic replacement (AVR) by major surgery.

Methods

45 patients with aortic stenosis (AS) undergoing TAVI and 33 AVR were assessed by standard echo Doppler the day before and 2 months after the implantation. 2D echocardiograms were performed to measure left ventricular (LV) mass index (LVMi), relative wall thickness (RWT), ejection fraction (EF) and the ratio between transmitral E velocity and early diastolic velocity of mitral annulus (E/e’ ratio). Valvular-arterial impedance (Zva) was also calculated.

Results

At baseline, the 2 groups were comparable for blood pressure, heart rate, body mass index mean transvalvular gradient and aortic valve area. TAVI patients were older (p<0.0001) and had greater LVMi (p<0.005) than AVR group. After 2 months, both the procedures induced a significant reduction of transvalvular gradient and Zva but the decrease of LVMi and RWT was significant greater after TAVI (both p<0.0001). E/e’ ratio and EF were significantly improved after both the procedure but E/e’ reduction was greater after TAVI (p<0.0001). TAVI exhibited greater percent reduction in mean transvalvular gradient (p<0.05), Zva (p<0.02), LVMi (p<0.0001), RWT (p<0.0001) and E/e’ ratio (p<0.0001) than AVR patients. Reduction of E/e’ ratio was positively related with reduction of RWT (r = 0.46, p<0.002) only in TAVI group, even after adjusting for age and percent reduction of Zva (r =0.43, p<0.005).

Conclusions

TAVI induces a greater improvement of estimated LV filling pressure in comparison with major prosthetic surgery, due to more pronounced recovery of LV geometry, independent on age and changes of hemodynamic load.