Comparison of plug-based versus suture-based vascular closure for large-bore arterial access: a collaborative meta-analysis of observational and randomized studies.

BACKGROUND: Large-bore arteriotomies can be percutaneously closed with suture-based or plug-based vascular closure device (VCD) strategies. The efficacy of both techniques remains controversial. AIMS: We conducted a meta-analysis of comparative studies between both VCD strategies, focusing on the most commonly applied VCDs (MANTA and ProGlide). METHODS: We searched MEDLINE, the Cochrane Central Register of Controlled Trials and Google scholar for observational studies (OS) and randomized controlled trials (RCT) comparing vascular closure with the MANTA-based and the ProGlide-based technique. The principal endpoint of this analysis was access-site related vascular complications. Both study types were analyzed separately. RESULTS: Access-site related vascular complications were less frequent after vascular closure with the MANTA technique in the analysis of OS (RR 0.61 [95%CI 0.43-0.89], p = 0.01, I2 = 0%), but more frequent in the analysis of RCT data (RR 1.70 [95%CI 1.16-2.51], p = 0.01, I2 = 0%). Both data sets provided no significant difference between the VCD techniques in terms of overall bleeding events (OS: RR 0.57 [95%CI 0.32-1.02], p = 0.06, I2 = 70%; and RCT: RR 1.37 [95%CI 0.82-2.28], p = 0.23, I2 = 30%). RCT data showed that endovascular stenting or vascular surgery due to VCD failure occurred more often after MANTA application (RR 3.53 [95%CI 1.07-11.33], p = 0.04, I2 = 0%). CONCLUSIONS: While OS point to favorable outcomes for large-bore vascular closure with the MANTA-based technique, RCT data show that this strategy is associated with more access-site related vascular complications as well as endovascular stenting or vascular surgery due to device failure compared with the ProGlide-based technique.

Safety and performance of a novel cerebral embolic protection device for transcatheter aortic valve implantation: the PROTEMBO C Trial.

BACKGROUND: Stroke remains a feared complication associated with transcatheter aortic valve implantation (TAVI). Embolic cerebral injury occurs in the majority of TAVI cases and can lead to cognitive dysfunction. AIMS: The PROTEMBO C Trial evaluated the safety and performance of the ProtEmbo Cerebral Protection System in TAVI patients. METHODS: Forty-one patients were enrolled in this single-arm study conducted at 8 European centres. The primary safety endpoint was the rate of VARC 2-defined major adverse cardiac and cerebrovascular events (MACCE) at 30 days; the primary performance endpoint was the composite rate of technical success versus performance goals (PG). Secondary endpoints included brain diffusion-weighted magnetic resonance imaging (DW-MRI), new lesion volume, and the rate of death or all strokes compared to historical data. RESULTS: Thirty-seven of 41 enrolled patients underwent TAVI with the ProtEmbo device (intention-to-treat [ITT] population). Both primary endpoints were met. MACCE at 30 days was 8.1% (upper limit of the 95% confidence interval [CI]: 21.3% vs PG 25%; p=0.009), and technical success was 94.6% (lower limit of the 95% CI: 82.3% vs PG 75%; p=0.003). New DW-MRI lesion volumes with ProtEmbo were smaller than in historical data, and 87% of patients completing MRI follow-up had no single lesion >150 mm3. There was 1 stroke in a patient in whom the device was removed prematurely before TAVI completion. CONCLUSIONS: The PROTEMBO C Trial met its primary safety and performance endpoints compared to prespecified historical PGs. Patients had smaller brain lesion volumes on DW-MRI compared to prior series and no larger single lesions. These results warrant further evaluation of the ProtEmbo in a larger randomised controlled trial (RCT).

Combined Coronary CT-Angiography and TAVI Planning: Utility of CT-FFR in Patients with Morphologically Ruled-Out Obstructive Coronary Artery Disease.

Background: Coronary artery disease (CAD) is a frequent comorbidity in patients undergoing transcatheter aortic valve implantation (TAVI). If significant CAD can be excluded on coronary CT-angiography (cCTA), invasive coronary angiography (ICA) may be avoided. However, a high plaque burden may make the exclusion of CAD challenging, particularly for less experienced readers. The objective was to analyze the ability of machine learning (ML)-based CT-derived fractional flow reserve (CT-FFR) to correctly categorize cCTA studies without obstructive CAD acquired during pre-TAVI evaluation and to correlate recategorization to image quality and coronary artery calcium score (CAC). Methods: In total, 116 patients without significant stenosis (≥50% diameter) on cCTA as part of pre-TAVI CT were included. Patients were examined with an electrocardiogram-gated CT scan of the heart and high-pitch scan of the torso. Patients were re-evaluated with ML-based CT-FFR (threshold = 0.80). The standard of reference was ICA. Image quality was assessed quantitatively and qualitatively. Results: ML-based CT-FFR was successfully performed in 94.0% (109/116) of patients, including 436 vessels. With CT-FFR, 76/109 patients and 126/436 vessels were falsely categorized as having significant CAD. With CT-FFR 2/2 patients but no vessels initially falsely classified by cCTA were correctly recategorized as having significant CAD. Reclassification occurred predominantly in distal segments. Virtually no correlation was found between image quality or CAC. Conclusions: Unselectively applied, CT-FFR may vastly increase the number of false positive ratings of CAD compared to morphological scoring. Recategorization was virtually independently from image quality or CAC and occurred predominantly in distal segments. It is unclear whether or not the reduced CT-FFR represent true pressure ratios and potentially signifies pathophysiology in patients with severe aortic stenosis.

Risk Assessment of Coronary Obstruction During Transcatheter Aortic Valve Replacement: Insights From Post-BASILICA Computed Tomography.

OBJECTIVES: The aim of this study was to examine the predictive value of preprocedural computed tomography (CT)-based risk stratification of coronary obstruction during transcatheter aortic valve replacement (TAVR) on the basis of geometric measurements on postprocedural CT. BACKGROUND: Proper patient selection for additional procedures to prevent coronary obstruction during TAVR has not been adequately evaluated. METHODS: Pre- and postprocedural computed tomographic scans of 28 patients treated using bioprosthetic or native aortic scallop intentional laceration to prevent iatrogenic coronary artery obstruction (BASILICA) and TAVR were analyzed. Using the postprocedural computed tomographic images, threatened coronary obstruction (TCO) was defined as: 1) ostial obstruction (adherence of the transcatheter heart valve [THV] to the coronary ostium with leaflet extension above the ostium); and/or 2) sinus sequestration (THV adherence to the sinotubular junction [STJ] with leaflet extension above the STJ) and was substratified into complete and incomplete types. RESULTS: A total of 51 leaflets were evaluated (88% surgical tissue valves) after excluding leaflets not visible on CT (n = 5). On postprocedural CT, complete TCO was observed in 25.4% (13 of 51 leaflets). On preprocedural CT, leaflets were at high risk for complete TCO (incidence 53%) if the virtual THV-to-coronary distance (VTC) was <3.0 mm, or if the virtual THV-to-STJ distance (VTSTJ) was <1.0 mm with STJ height - leaflet length <0 mm (leaflet-STJ mismatch). Leaflets were at low risk (incidence 0%) if the VTC was ≥3 mm and VTSTJ was ≥3.0 mm or STJ height - leaflet length was ≥+2.0 mm. Of 28 leaflets treated using BASILICA, complete TCO was seen in 35.7% (n = 10), due to sinus sequestration (100%) with coexisting ostial obstruction (30%). Actual coronary events occurred in 7.1% (n = 2) because of leaflet prolapse, corresponding to an absolute risk reduction by BASILICA of 29% (P = 0.021). CONCLUSIONS: Risk assessment of coronary obstruction after TAVR may improve with a multiparametric approach incorporating VTC, VTSTJ, and leaflet-STJ mismatch. BASILICA appeared to reduce actual coronary events even in leaflets with anticipated coronary obstruction.

Manta versus Perclose ProGlide vascular closure device after transcatheter aortic valve implantation: Initial experience from a large European center.

BACKGROUND: Vascular and bleeding complications are common after transcatheter aortic valve implantation (TAVI) and are associated with worse outcomes. The plug-based Manta (M) vascular closure device (VCD) is a novel option to achieve haemostasis for large-bore arterial access sites. OBJECTIVE: We aimed to compare vascular and bleeding complications between the M-VCD and the established suture-based Perclose ProGlide (P)-VCD. METHODS: From February to September 2019 a total of 578 patients underwent transfemoral TAVI at a single high-volume centre. Access site closure was performed using M-VCD in 195 patients (33.7%) and P-VCD in 383 patients (66.3%). We assessed vascular and access site-related complications as well as bleeding events according to the Valve Academic Research Consortium-2 definition. RESULTS: Overall vascular complications occurred less frequently in the M-VCD group (10.7% vs. 19.0%, p = 0.011) driven by a significantly lower rate of major vascular events (2.0% vs. 6.5%, p = 0.025). Access site-related complications were significantly less frequent in the M-VCD cohort (10.7% vs. 16.6%, p = 0.048). The M-VCD was associated with significantly lower rates of major (0.5% vs. 4.4%, p = 0.009) and life-threatening bleeding (0% vs. 2.3%, p = 0.032). In multivariable analysis, the use of M-VCD was the only independent predictor of vascular complications (odds ratio 0.54, 95% confidence interval 0.32-0.91, p = 0.022). CONCLUSIONS: The M-VCD was associated with a reduction of vascular and access-site complications as well as severe bleeding after transfemoral TAVI compared to the P-VCD in this observational study.

Combined cCTA and TAVR Planning for Ruling Out Significant CAD: Added Value of ML-Based CT-FFR.

OBJECTIVES: The purpose of this study was to analyze the ability of machine-learning (ML)-based computed tomography (CT)-derived fractional flow reserve (CT-FFR) to further improve the diagnostic performance of coronary CT angiography (cCTA) for ruling out significant coronary artery disease (CAD) during pre-transcatheter aortic valve replacement (TAVR) evaluation in patients with a high pre-test probability for CAD. BACKGROUND: CAD is a frequent comorbidity in patients undergoing TAVR. Current guidelines recommend its assessment before TAVR. If significant CAD can be excluded on cCTA, invasive coronary angiography (ICA) may be avoided. Although cCTA is a very sensitive test, it is limited by relatively low specificity and positive predictive value, particularly in high-risk patients. METHODS: Overall, 460 patients (age 79.6 ± 7.4 years) undergoing pre-TAVR CT were included and examined with an electrocardiogram-gated CT scan of the heart and high-pitch scan of the vascular access route. Images were evaluated for significant CAD. Patients routinely underwent ICA (388/460), which was omitted at the discretion of the local Heart Team if CAD could be effectively ruled out on cCTA (72/460). CT examinations in which CAD could not be ruled out (CAD+) (n = 272) underwent additional ML-based CT-FFR. RESULTS: ML-based CT-FFR was successfully performed in 79.4% (216/272) of all CAD+ patients and correctly reclassified 17 patients as CAD negative. CT-FFR was not feasible in 20.6% because of reduced image quality (37/56) or anatomic variants (19/56). Sensitivity, specificity, positive predictive value, and negative predictive value were 94.9%, 52.0%, 52.2%, and 94.9%, respectively. The additional evaluation with ML-based CT-FFR increased accuracy by Δ+3.4% (CAD+: Δ+6.0%) and raised the total number of examinations negative for CAD to 43.9% (202/460). CONCLUSIONS: ML-based CT-FFR may further improve the diagnostic performance of cCTA by correctly reclassifying a considerable proportion of patients with morphological signs of obstructive CAD on cCTA during pre-TAVR evaluation. Thereby, CT-FFR has the potential to further reduce the need for ICA in this challenging elderly group of patients before TAVR.

Comparison of a Pure Plug-Based Versus a Primary Suture-Based Vascular Closure Device Strategy for Transfemoral Transcatheter Aortic Valve Replacement: The CHOICE-CLOSURE Randomized Clinical Trial.

BACKGROUND: Transcatheter aortic valve replacement is an established treatment option for patients with severe symptomatic aortic stenosis and is most commonly performed through the transfemoral access route. Percutaneous access site closure can be achieved using dedicated plug-based or suture-based vascular closure device (VCD) strategies, but randomized comparative studies are scarce. METHODS: The CHOICE-CLOSURE trial (Randomized Comparison of Catheter-based Strategies for Interventional Access Site Closure during Transfemoral Transcatheter Aortic Valve Implantation) is an investigator-initiated, multicenter study, in which patients undergoing transfemoral transcatheter aortic valve replacement were randomly assigned to vascular access site closure using either a pure plug-based technique (MANTA, Teleflex) with no additional VCDs or a primary suture-based technique (ProGlide, Abbott Vascular) potentially complemented by a small plug. The primary end point consisted of access site- or access-related major and minor vascular complications during index hospitalization, defined according to the Valve Academic Research Consortium-2 criteria. Secondary end points included the rate of access site- or access-related bleeding, VCD failure, and time to hemostasis. RESULTS: A total of 516 patients were included and randomly assigned. The mean age of the study population was 80.5±6.1 years, 55.4% were male, 7.6% of patients had peripheral vascular disease, and the mean Society of Thoracic Surgeons score was 4.1±2.9%. The primary end point occurred in 19.4% (50/258) of the pure plug-based group and 12.0% (31/258) of the primary suture-based group (relative risk, 1.61 [95% CI, 1.07-2.44], P=0.029). Access site- or access-related bleeding occurred in 11.6% versus 7.4% (relative risk, 1.58 [95%CI: 0.91-2.73], P=0.133) and device failure in 4.7% versus 5.4% (relative risk, 0.86, [95% CI, 0.40-1.82], P=0.841) in the respective groups. Time to hemostasis was significantly shorter in the pure plug-based group (80 [32-180] versus 240 [174-316] seconds, P<0.001). CONCLUSIONS: Among patients treated with transfemoral transcatheter aortic valve replacement, a pure plug-based vascular closure technique using the MANTA VCD is associated with a higher rate of access site- or access-related vascular complications but a shorter time to hemostasis compared with a primary suture-based technique using the ProGlide VCD. Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT04459208.

Combined Coronary CT-Angiography and TAVI-Planning: A Contrast-Neutral Routine Approach for Ruling-out Significant Coronary Artery Disease.

BACKGROUND: Significant coronary artery disease (CAD) is a common finding in patients undergoing transcatheter aortic valve implantation (TAVI). Assessment of CAD prior to TAVI is recommended by current guidelines and is mainly performed via invasive coronary angiography (ICA). In this study we analyzed the ability of coronary CT-angiography (cCTA) to rule out significant CAD (stenosis ≥ 50%) during routine pre-TAVI evaluation in patients with high pre-test probability for CAD. METHODS: In total, 460 consecutive patients undergoing pre-TAVI CT (mean age 79.6 ± 7.4 years) were included. All patients were examined with a retrospectively ECG-gated CT-scan of the heart, followed by a high-pitch-scan of the vascular access route utilizing a single intravenous bolus of 70 ml iodinated contrast medium. Images were evaluated for image quality, calcifications, and significant CAD; CT-examinations in which CAD could not be ruled out were defined as positive (CAD+). Routinely, patients received ICA (388/460; 84.3%; Group A), which was omitted if renal function was impaired and CAD was ruled out on cCTA (Group B). Following TAVI, clinical events were documented during the hospital stay. RESULTS: cCTA was negative for CAD in 40.2% (188/460). Sensitivity, specificity, PPV, and NPV in Group A were 97.8%, 45.2%, 49.6%, and 97.4%, respectively. Median coronary artery calcium score (CAC) was higher in CAD+-patients but did not have predictive value for correct classification of patients with cCTA. There were no significant differences in clinical events between Group A and B. CONCLUSION: cCTA can be incorporated into pre-TAVI CT-evaluation with no need for additional contrast medium. cCTA may exclude significant CAD in a relatively high percentage of these high-risk patients. Thereby, cCTA may have the potential to reduce the need for ICA and total amount of contrast medium applied, possibly making pre-procedural evaluation for TAVI safer and faster.

Measurement of effective refractive index differences in multimode optical fibers based on modal decomposition.

We demonstrate the nondestructive measurement of the effective refractive index difference of two arbitrary modes within a multimode optical fiber by utilizing a tunable fiber grating. We use a mechanical grating of variable period to couple the respective modes and measure the mode content at the fiber output based on the correlation filter technique. From the dependence of the coupling efficiency on the grating period, the effective index difference of the modes can be extracted with high accuracy.