Fiber optic cadmium ion sensors based on functionalization of a magnetic ion-imprinted polymer.

Cadmium poisoning is a chronic accumulation process, and long-term drinking of even low cadmium content water will cause kidney damage, so an ultra-low detection limit is particularly important. However, at the present stage, the traditional detection method cannot reach a sufficiently low detection limit, the response time is too long, and the cost of detection is very high, so that real-time measurement cannot be realized. Therefore, the traditional cadmium ion detection method has a slow response and an insufficient detection limit. This paper presents a fiber optic cadmium ion sensor functionalized based on an Fe3O4@SiO2@CS magnetic ion imprinting polymer (M-IIP). The sensor is based on the coupling characteristics of the optical microfiber coupler (OMC) cone region to achieve a highly sensitive response to the change in the cadmium ion concentration. M-IIP materials were prepared by surface imprinting polymerization to achieve low cross-sensitivity and thus improve the detection limit of the sensor. The results show that the developed fiber sensor has high specificity and a rapid response to cadmium ions. The experimental limit of detection (LOD) reached 0.051 nM within 0-1 µM with a response time of less than 50 s. Moreover, the proposed fiber cadmium ion sensor exhibits excellent performance in terms of sensitivity, stability, repeatability and biocompatibility.

Outcomes Following Transcatheter Aortic Valve Replacement for Aortic Stenosis in Patients With Type 0 Bicuspid, Type 1 Bicuspid, and Tricuspid Aortic Valves.

BACKGROUND: Data concerning the outcomes of transcatheter aortic valve replacement in type 0 bicuspid aortic stenosis (AS) are scarce. The study aims to compare the outcomes of transcatheter aortic valve replacement for AS in patients with type 0 bicuspid, type 1 bicuspid, and tricuspid aortic valve anatomy. METHODS: We enrolled consecutive patients undergoing transcatheter aortic valve replacement for severe AS between 2012 and 2022 in this single-center retrospective cohort study. The primary outcome was mortality, while secondary outcomes included in-hospital complications such as stroke and pacemaker implantation and transcatheter heart valve hemodynamic performance. RESULTS: The number of patients with AS with type 0 bicuspid, type 1 bicuspid, and tricuspid aortic valve anatomy was 328, 302, and 642, respectively. Self-expanding transcatheter heart valves were used in the majority of patients (n=1160; 91.4%). In the matched population, differences in mortality (30 days: 4.2% versus 1.7% versus 1.7%, Poverall=0.522; 1 year: 10% versus 2.3% versus 6.2%, Poverall=0.099) and all stroke (30 days: 1.0% versus 0.9% versus 0.0%, Poverall=0.765; 1 year: 1.4% versus 1.6% versus 1.3%, Poverall=NS) were nonsignificant, and the incidence of overall in-hospital complications was comparable among groups. Ascending aortic diameter was the single predictor of 1-year mortality in type 0 bicuspid patients (hazard ratio, 1.59 [95% CI, 1.03-2.44]; P=0.035). The proportion of patients with a mean residual gradient ≥20 mm Hg was the highest in those with type 0 bicuspid anatomy, although the need for permanent pacemaker implantation was the lowest in this group. CONCLUSIONS: Major clinical outcomes of transcatheter aortic valve replacement for AS in patients with type 0 bicuspid, type 1 bicuspid, and tricuspid aortic valve anatomy are equivalent at short- and mid-term follow-up. These observations merit further exploration in prospective international registries and randomized controlled trials.

Sex Difference in Outcomes Following Transcatheter Aortic Valve Replacement in Bicuspid Aortic Stenosis.

BACKGROUND: It is unknown whether the sex difference whereby female transcatheter aortic valve replacement (TAVR) candidates had a lower risk profile, a higher incidence of in-hospital complications, but more favorable short- and long-term survival observed in tricuspid cohorts undergoing TAVR would persist in patients with bicuspid aortic valves (BAVs). OBJECTIVES: The aim of this study was to reexamine the impact of sex on outcomes following TAVR in patients with BAVs. METHODS: In this single-center study, patients with BAVs undergoing TAVR for severe aortic stenosis from 2012 to 2021 were retrospectively included. Baseline characteristics, aortic root anatomy, and in-hospital and 1-year valve hemodynamic status and survival were compared between sexes. RESULTS: A total of 510 patients with BAVs were included. At baseline, women presented with fewer comorbidities. Men had a greater proportion of Sievers type 1 BAV, higher calcium volumes (549.2 ± 408.4 mm3 vs 920.8 ± 654.3 mm3; P < 0.001), and larger aortic root structures. Women experienced more vascular complications (12.9% vs 4.9%; P = 0.002) and bleeding (11.1% vs 5.3%; P = 0.019) and higher residual gradients (16.9 ± 7.7 mm Hg vs 13.2 ± 6.4 mm Hg; P < 0.001), while men were more likely to undergo second valve implantations during index TAVR (6.3% vs 15.9%; P = 0.001). Death at 1 year was not significantly different between sexes (HR: 1.15; 95% CI: 0.56-2.35; P = 0.70). Bleeding (adjusted HR: 4.62; 95% CI: 1.51-14.12; P = 0.007) was the single independent predictor of 1-year death for women. CONCLUSIONS: In patients with BAVs undergoing TAVR, women presented with fewer comorbidities, while men had a greater proportion of type 1 BAV, more calcification, and larger aortic roots. In-hospital outcomes favored men, with fewer complications except for the need for second valve implantation, but 1-year survival was comparable between sexes.

A CT-based technique to predict optimal projection for self-expanding TAVI in patients with different aortic valve anatomies.

BACKGROUND: Optimal projection is essential for valve deployment during transcatheter aortic valve implantation (TAVI). The purpose of this study was to propose an approach to predict optimal projection in TAVI candidates with different aortic valve anatomies. METHODS: 331 patients undergoing self-expanding TAVI were included and the so-called non-coronary cusp (NCC)-parallel technique was utilized, which generated the predicted projection by connecting NCC commissures on the transverse plane on the pre-procedural computed tomography images. RESULTS: 37.8% of the study cohort were bicuspid aortic valve (BAV) patients. Around 80% of both NCC-parallel views and final views were in the right anterior oblique (RAO) and caudal (CAU) quadrant. There was less than 5° change required from the NCC-parallel view to the final implanted view in 79% of tricuspid aortic valve (TAV) patients but only in 27% (13/48) of type 0 BAV patients with coronary arteries originated from the different cusps. After excluding the above mentioned BAV patients, 62.3% (48/77) of BAV patients needed less than 5° change to achieve optimal projection and only in 8 patients, the angular change was larger than 10° in either left/right anterior oblique or cranial/caudal direction. CONCLUSIONS: The NCC-parallel technique provides reliable prediction for optimal projection in self-expanding TAVI in all TAV and most BAV patients, with a vast majority of views in the RAO and CAU quadrant.

The incidence and predictors of high-degree atrioventricular block in patients with bicuspid aortic valve receiving self-expandable transcatheter aortic valve implantation.

BACKGROUND: The high-degree atrioventricular block (HAVB) in patients with bicuspid aortic valve (BAV) treated with transcatheter aortic valve implantation (TAVI) remains high. The study aims to explore this poorly understood subject of mechanisms and predictors for HAVB in BAV self-expandable TAVI patients. METHODS: We retrospectively included 181 BAV patients for analysis. Using computed tomography data, the curvature of ascending aorta (AAo) was quantified by the angle (AAo angle) between annulus and the cross-section at 35 mm above annulus (where the stent interacts with AAo the most). The valvular anatomy and leaflet calcification were also characterized. RESULTS: The 30-day HAVB rate was 16.0% (median time to HAVB was three days). Type-1 morphology was found in 79 patients (43.6%) (left- and right-coronary cusps fusion comprised 79.7%). Besides implantation below membrane septum, large AAo angle [odds ratio (OR) = 1.08, P = 0.016] and type-1 morphology (OR = 4.97, P = 0.001) were found as the independent predictors for HAVB. Together with baseline right bundle branch block, these predictors showed strong predictability for HAVB with area under the cure of 0.84 (sensitivity = 62.1%, specificity = 92.8%). Bent AAo and calcified raphe had a synergistic effect in facilitating high implantation, though the former is associated with at-risk deployment (device implanted above annulus + prothesis pop-out, versus straight AAo: 9.9% vs. 2.2%, P = 0.031). CONCLUSIONS: AAo curvature and type-1 morphology are novel predictors for HAVB in BAV patients following self-expandable TAVI. For patients with bent AAo or calcified raphe, a progressive approach to implant the device above the lower edge of membrane septum is favored, though should be done cautiously to avoid pop-out.

Reshaping bicuspid aortic valve stenosis with an hourglass-shaped balloon for transcatheter aortic valve replacement: A pilot study.

OBJECTIVES: We evaluated the safety and usefulness of preparatory anatomical reshaping with a geometric hourglass-shaped balloon to optimize transcatheter aortic valve replacement (TAVR) outcomes in bicuspid aortic valve (BAV) stenosis. BACKGROUND: TAVR has been increasingly performed for BAV stenosis; however, technical challenges remain. Procedural results are suboptimal given unfavorable valvular anatomies. METHODS: Eligible patients with BAV stenosis were enrolled to undergo aortic valve predilatation with the hourglass-shaped TAV8 balloon before TAVR using the self-expandable Venus A-Valve. Procedural details and outcomes were compared to a sequential group of patients with BAV who underwent TAVR with the same device following preparatory dilatation using a cylindrical balloon. RESULTS: A total of 22 patients were enrolled in the TAV8 group and 53 were included in the control group. Valve downsizing was less common in the TAV8 group (36.4 vs. 67.9%; p = .012). Stable valve release and optimal implant depth were consistently achieved in the TAV8 group with no requirement for a second valve (0 vs. 17.0%; p = .039) and with higher device success rates (100.0 vs 77.4%; p = .014). Residual aortic regurgitation graded as ≥mild was less common in the TAV8 group (13.6 vs 45.3%; p = .009). Mortality was similar (0 vs. 3.8%; p = 1); no major/disabling stroke or conversion to open-heart surgery was seen in either group within 30 days. CONCLUSIONS: Compared with standard cylindrical balloon valvuloplasty, preparatory reshaping with the hourglass-shaped balloon before self-expandable TAVR in BAV was associated with significantly better procedural results and may encourage more promising outcomes.

Transcatheter Aortic Valve Replacement in Patients with Aortic Stenosis Having Coronary Cusp Fusion versus Mixed Cusp Fusion Nonraphe Bicuspid Aortic Valve.

OBJECTIVES: We aimed to assess the procedural and clinical results of transcatheter aortic valve replacement (TAVR) for nonraphe bicuspid aortic stenosis (AS) with coronary vs mixed cusp fusion. BACKGROUND: It remains unclear whether cusp fusion morphology affects TAVR outcomes in patients with nonraphe bicuspid AS. METHODS: This retrospective study enrolled consecutive patients with severe symptomatic AS and type-0 bicuspid aortic valve, who underwent TAVR at our institution between 2012 and 2017. TAVR outcomes were defined based on the Valve Academic Research Consortium-2 recommendations. RESULTS: Compared to patients with mixed cusp fusion (44/71), those with coronary cusp fusion (27/71) had a larger ellipticity index for the aortic annulus (21.9% ± 9.0% vs 15.6% ± 9.3%, p=0.007) and increased left ventricular outflow tract obstruction (31.1% ± 9.4% vs 26.9% ± 7.5%, p=0.04) but comparable rates of second valve implantation (15.9% vs 14.8%), mild paravalvular leakage (PVL, 38.5% vs 30.2%), permanent pacemaker implantation (PPM, 25.9% vs 15.9%), and 30-day mortality (7.4% vs 6.8%). Use of a first-generation transcatheter heart valve was associated with higher risk for mild PVL (odds ratio (OR) = 4.37; 95% confidence interval (95% CI) = 1.14-16.75; p=0.03) but not PPM (OR = 0.77; 95% CI = 0.22-2.62; p=0.67), whereas a larger oversizing ratio tended to be associated with a higher PPM rate (OR = 1.49; 95% CI = 0.46-4.86; p=0.51) but lower incidence of mild PVL (OR = 0.51; 95% CI = 0.19-1.35; p=0.17). CONCLUSIONS: In AS patients with type-0 bicuspid valves, cusp fusion morphology does not affect the procedural or clinical results of TAVR. Use of second-generation transcatheter heart valves may provide more favorable results in such patients. This trial is registered with NCT01683474.

Progression of the Ascending Aortic Diameter After Transcatheter Aortic Valve Implantation: Based on Computed Tomography Images.

OBJECTIVES: The natural history of ascending aortic diameter after transcatheter aortic valve implantation (TAVI) has not been investigated. Our aim was to determine the progression of ascending aortic diameter in patients undergoing TAVI. METHODS: We retrospectively included 134 patients undergoing TAVI for aortic stenosis at our institution from June 2012 to November 2016, including 79 patients with bicuspid aortic valve (BAV) and 55 patients with tricuspid aortic valve (TAV). Preoperative measurements of the ascending aorta were compared with aortic measurements at 1-year follow-up based on computed tomography images. RESULTS: A very slight decrease in median aortic diameter was identified in overall patients: 4.07 cm (interquartile range [IQR], 3.76-4.54 cm) vs 4.06 cm (IQR, 3.74-4.51 cm); P=.04. Further subgroup analysis found that the decrease remained statistically significant in the subgroup of TAV and mild aortic dilation. In addition, no aortic events occurred during long-term follow-up (median, 27 months; IQR, 20-42 months). CONCLUSIONS: TAVI could prevent a further progression of aortic diameter for both BAV or TAV patients by correcting hemodynamic derangements, especially for patients with TAV, mild aortic dilation, and small annulus angles. Aortic events appeared rarely during long-term follow-up after TAVI. However, our results need further confirmation with future investigations in a larger population with longer-term follow-up.

Comparison of procedural, clinical and valve performance results of transcatheter aortic valve replacement in patients with bicuspid versus tricuspid aortic stenosis.

BACKGROUND: Limited date describing the procedural, clinical and valve performance results of transcatheter aortic valve replacement (TAVR) in patients with bicuspid versus tricuspid aortic stenosis (TAV). METHODS: Procedural and clinical results were defined and reported according to VARC-2 criteria. RESULTS: Consecutive 87 patients with BAV and 70 patients with TAV were included. Compared to patients with TAV, patients with BAV had similar incidence of second valve implantation (14.9% vs 12.9%, p=0.708), more than mild paravalvular leakage (PVL, 40.2% vs 31.9%, p=0.288), permanent pacemaker implantation (PPM, 24.1% vs 28.6%, p=0.53). Furthermore, the procedural and clinical results of TAVR also did not differ between patients with type 0 and type 1 (second valve implantation: 18.4% vs 11.8%, p=0.71, PVL: 38.8% vs 41.2%, p=0.83, PPM: 18.4% vs 31.6%, p=0.16). The hemodynamic outcomes were similar in patients with BAV and TAV at 1-year (maximum velocity, 2.3 vs 2.2m/s, p=0.307) and 2-year (2.3 vs 2.1m/s, p=0.184) follow-up respectively. Adjusted binary logistic regression analysis found oversizing ratio at 14.45-20.57% is at lower risk for more than mild PVL (OR, 0.069, 95% CI, 0.011-0.428, p=0.004). Moreover, the Kaplan-Meier survival analysis revealed that TAVR in type 0 BAV, type 1 BAV and TAV have comparable risk for midterm mortality (Log rank, p=0.772). CONCLUSION: TAVR in whatever type of BAV appeared to be safe and efficacy, and TAVR in BAV was associated with comparable bioprosthetic function during follow up compared to patients with TAV.