Long-Term Outcomes of Aortic Stenosis Patients with Different Flow/Gradient Patterns Undergoing Transcatheter Aortic Valve Implantation.

Background: Few data exist on the comparative long-term outcomes of severe aortic stenosis (AS) patients with different flow-gradient patterns undergoing transcatheter aortic valve implantation (TAVI). This study sought to evaluate the impact of the pre-TAVI flow-gradient pattern on long-term clinical outcomes after TAVI and assess changes in the left ventricular ejection fraction (LVEF) of different subtypes of AS patients following TAVI. Methods: Consecutive patients with severe AS undergoing TAVI in our institution were screened and prospectively enrolled. Patients were divided into four subgroups according to pre-TAVI flow/gradient pattern: (i) low flow-low gradient (LF-LG): stroke volume indexed (SVi) ≤ 35 mL/m2 and mean gradient (MG) < 40 mmHg); (ii) normal flow-low gradient (NF-LG): SVi > 35 mL/m2 and MG < 40 mmHg; (iii) low flow-high gradient (LF-HG): Svi 35 mL/m2 and MG ≥ 40 mmHg and (iv) normal flow-high gradient (NF-HG): SVi > 35 mL/m2 and MG ≥ 40 mmHg. Transthoracic echocardiography was repeated at 1-year follow-up. Clinical follow-up was obtained at 12 months, and yearly thereafter until 5-year follow-up was complete for all patients. Results: A total of 272 patients with complete echocardiographic and clinical follow-up were included in our analysis. Their mean age was 80 ± 7 years and the majority of patients (N = 138, 50.8%) were women. 62 patients (22.8% of the study population) were distributed in the LF-LG group, 98 patients (36%) were LF-HG patients, 95 patients (34.9%) were NF-HG, and 17 patients (6.3%) were NF-LG. There was a greater prevalence of comorbidities among LF-LG AS patients. One-year all-cause mortality differed significantly between the four subgroups of AS patients (log-rank p: 0.022) and was more prevalent among LF-LG patients (25.8%) compared to LF-HG (11.3%), NF-HG (6.3%) and NF-LG patients (18.8%). At 5-year follow-up, global mortality remained persistently higher among LF-LG patients (64.5%) compared to LF-HG (47.9%), NF-HG (42.9%), and NF-LG patients (58.8%) (log-rank p: 0.029). At multivariable Cox hazard regression analysis, baseline SVi (HR: 0.951, 95% C.I.; 0.918-0.984), the presence of at least moderate tricuspid regurgitation at baseline (HR: 3.091, 95% C.I: 1.645-5.809) and at least moderate paravalvular leak (PVL) post-TAVI (HR: 1.456, 95% C.I.: 1.106-1.792) were significant independent predictors of late global mortality. LF-LG patients and LF-HG patients exhibited a significant increase in LVEF at 1-year follow-up. A lower LVEF (p < 0.001) and a lower Svi (p < 0.001) at baseline were associated with LVEF improvement at 1-year. Conclusions: Patients with LF-LG AS have acceptable 1-year outcomes with significant improvement in LVEF at 1-year follow-up, but exhibit exceedingly high 5-year mortality following TAVI. The presence of low transvalvular flow and at least moderate tricuspid regurgitation at baseline and significant paravalvular leak post-TAVI were associated with poorer long-term outcomes in the entire cohort of AS patients. The presence of a low LVEF or a low SVi predicts LVEF improvement at 1-year.

Chromium(VI) Removal from Water by Lanthanum Hybrid Modified Activated Carbon Produced from Coconut Shells.

Cr(VI) is considered to be the most hazardous and toxic oxidation state of chromium and hence the development of effective removal technologies, able to provide water with Cr(VI) below the drinking water limits (US EPA 100 µg/L, European Commission 50 µg/L, which will be reduced to 25 by 2036) is a very important issue in water treatment. This study aimed at examining the performance of activated carbon produced from coconut shells, modified by lanthanum chloride, for Cr(VI) removal from waters. The structure of the formed material (COC-AC-La) was characterized by the application of BET, FTIR and SEM techniques. The effect of the adsorbent's dosage, pH value, contact time, initial Cr(VI) concentration and water matrix was examined with respect to Cr(VI) removal. The results indicated that the maximum Cr(VI) removal was observed at pH 5; 4 h contact time and 0.2 g/L of adsorbent's dosage was adequate to reduce Cr(VI) from 100 µg/L to below 25 µg/L. Freundlich isotherm and pseudo-second order kinetic models fitted the experimental data sufficiently. The maximum adsorption capacity achieved was 6.3 µg/g at pH 5. At this pH value, the removal percentage of Cr(VI) reached 95% for an initial Cr(VI) concertation of 30 µg/L. At pH 7 the corresponding efficiency was roughly 60%, resulting in residual Cr(VI) concentrations below the anticipated drinking water limit of 25 µg/L of total chromium, when the initial Cr(VI) concentration was 50 µg/L. Consecutive adsorption and regeneration studies were conducted using 0.01 M of NaOH as an eluent to evaluate the reusability of the adsorbents, Results showed 20% decrease of adsorption capacity after 5 regeneration cycles of operation.

Long-Term Outcomes and Valve Performance in Patients Undergoing Transcatheter Aortic Valve Implantation.

Transcatheter aortic valve implantation (TAVI) is an established method for treating patients with aortic valve stenosis. We sought to determine the long-term clinical outcomes and performance of a self-expanding bioprosthesis beyond 5 years. Consecutive patients scheduled for TAVI were included in the analysis. Primary end points were all-cause and cardiovascular mortality, structural valve deterioration (SVD) and bioprosthetic valve failure (BVF), based on the VARC-2 criteria and consensus statement by ESC/EAPCI. The study prospectively evaluated 273 patients (80.61 ± 7.00 years old, 47% females) who underwent TAVI with CoreValve/Evolut-R (Medtronic Inc.). The median follow-up duration was 5 years (interquartile range: 2.9 to 6; longest: 8 years). At 1, 5, and 8 years, estimated survival rates were 89.0%, 61.1%, and 56.0%, respectively, while cardiovascular mortality was 8% at the end of follow-up. Regarding valve performance, 5% of patients had early BVF and 1% had late BVF. Concerning SVD, 16 patients (6% of the total population) had moderate SVD (91% had an increase in mean gradient), with no severe SVD cases. Five patients with SVD died during follow-up. Actual analysis of the 8-year cumulative incidence of function of moderate SVD was 5.9% (2.5% to 16.2%). At multivariate analysis, the factor that emerged as an independent predictor for future SVD, was smaller bioprosthetic valve size (HR 0.58, 95% CI 0.41 to 0.82, p = 0.002). Long-term evaluation beyond 5 years after TAVI with a self-expanding bioprosthesis demonstrated low rates of cardiovascular mortality and structural valve deterioration. Valve size was an independent predictor for SVD.

One-year clinical and echocardiographic outcomes of direct implantation of a self-expanding valve.

OBJECTIVE: To present 1 year clinical and echocardiographic outcomes of the randomized DIRECT (Pre-dilatation in Transcatheter Aortic Valve Implantation Trial) trial. BACKGROUND: Intermediate-term data from randomized studies investigating the safety and efficacy of direct implantation are lacking. METHODS: DIRECT trial randomized 171 consecutive patients with severe aortic stenosis at four tertiary centers to undergo TAVI with the use of self-expanding prostheses with (pre-BAV) or without pre-dilatation (no-BAV). The primary endpoint was device success according to the VARC-2 criteria. All patients underwent a clinical and echocardiographic follow-up at 1 year. All-cause and cardiac mortality, stroke, heart failure hospitalization, and new pacemaker implantation were recorded. RESULTS: At 1 year, four deaths were recorded in pre-BAV group (4.7%) and three deaths in no-BAV group (3.5%). There was no difference in Kaplan-Meier plots between the two groups in all-cause mortality at 1 year (log-rank p = .72). Similarly, there was no difference in the incidence of permanent pacemaker implantation between the two groups at 1 year (27/67-40.3% in no-BAV group versus 20/69-29% in pre-BAV group, log-rank p = .24). There was no significant difference between pre-BAV and no BAV group in aortic valve area (1.84 ± 0.39 cm2 vs. 1.85 ± 0.44 cm2 , p = .90), mean aortic valve gradient (8.36 ± 5.04 vs. 8.00 ± 4.04 mmHg, p = .65) and moderate or severe paravalvular regurgitation (5-6.6 vs. 4-5.7%, respectively) at 1 year. The same applied independently from the performance of post-dilatation at baseline. CONCLUSIONS: Direct, without pre-dilatation, implantation of a self-expanding valve has no impact on one-year clinical and echocardiographic outcomes, independently also from the baseline performance of post-dilatation.

The impact of transcatheter aortic valve implantation on arterial stiffness and wave reflections.

BACKGROUND: The study of arterial properties in patients with aortic valve stenosis who undergo transcatheter aortic valve implantation (TAVI) remains challenging and results so far seem equivocal. We sought to investigate the acute and long-term effect of TAVI on arterial stiffness and wave reflections. METHODS: We enrolled 90 patients (mean age 80.2 ± 8.1 years, 50% males) with severe symptomatic aortic stenosis undergoing TAVI. Arterial stiffness was assessed by carotid-femoral and brachial-ankle pulse wave velocity (cfPWV and baPWV). Augmentation index corrected for heart rate (AIx@75), central pressures and subendocardial viability ratio (SEVR) were assessed with arterial tonometry. Measurements were conducted at baseline, after TAVI and at 1 year. RESULTS: Immediately after TAVI there was an increase in arterial stiffness (7.5 ± 1.5 m/s vs 8.4 ± 1.7 m/s, p = .001 for cfPWV and 1773 ± 459 vs 2383 ± 645 cm/s, p < .001 for baPWV) that was retained at 1 year (7.5 ± 1.5 m/s vs 8.7 ± 1.7 m/s, p < .001 and 1773 ± 459 cm/s vs 2286 ± 575, p < .001). Post-TAVI we also observed a decrease in AIx@75 (32.2 ± 12.9% vs 27.9 ± 8.4%, p = .016) that was attenuated 1 year later (32.2 ± 12.9% vs 29.8 ± 9.1%, p = .38), and an increase in SEVR (131.2 ± 30.0% vs 148.4 ± 36.1%, p = .002), which remained improved at 1 year (131.2 ± 30.0% vs 146.0 ± 32.2%, p = .01). CONCLUSIONS: After TAVI the arterial system exhibits an increase of stiffness in response to the acute relief of the obstruction, which is retained in the long term.

Impact of Valve Over-Sizing After Transcatheter Aortic Valve Implantation With a Self-Expanding Valve: A Multislice Computed Tomography Study.

BACKGROUND: In transcatheter aortic valve implantation (TAVI), prosthesis over-sizing prevents paravalvular leak (PVL). Strategies of over-sizing for self-expanding bioprostheses are not well established at present. METHODS: Patients with aortic valve stenosis scheduled for TAVI underwent preprocedural multislice computed tomography. Based on the degree of over-sizing, a ROC curve was drawn to define the optimal value of valve sizing for reducing PVL after TAVI. RESULTS: A total of 152 consecutive patients were included in the study (mean age, 79.95 ± 7.71 years; log EuroScore: 23.87 ± 8.93%). Based on the ROC curve, sizing of 14% was the optimal that would lead to less moderate/severe PVL (P<.01). Group 1 was defined as sizing <14% (n = 49 patients) and group 2 was defined as sizing ≥14% (n = 103 patients). During a follow-up period of 36 ± 14 months, a total of 9 patients died from group 1 vs 4 patients from group 2 (P<.01). Two of the patients who died had moderate/severe PVL and 11 had no/mild PVL (P=.27). From the population, a total of 49 patients (32%) were found to be in the "borderline" zone. Patients who received the smaller valve had lower mean left ventricular outflow tract diameter (P=.048), higher rate of calcium load (mild: 10 [32%] vs 13 [72%]; moderate: 16 [52%] vs 3 [17%]; severe: 5 [16%] vs 2 [11%]; P=.02) and lower mean of sinus of Valsalva diameter (P=.046) compared with patients who received the bigger valve. CONCLUSIONS: In patients undergoing TAVI, over-sizing the prosthesis at least 14% reduces PVL. In borderline cases, taking into consideration additional anatomical parameters may result in low rates of PVL.