Complete filter-based cerebral embolic protection with transcatheter aortic valve replacement.

OBJECTIVES: To evaluate the value of left vertebral artery filter protection in addition to the current filter-based embolic protection technology to achieve complete cerebral protection during TAVR. BACKGROUND: The occurrence of cerebrovascular events after transcatheter aortic valve replacement (TAVR) has fueled concern for its potential application in younger patients with longer life expectancy. Transcatheter cerebral embolic protection (TCEP) devices may limit periprocedural cerebrovascular events by preventing macro and micro-embolization to the brain. Conventional filter-based TCEP devices cover three extracranial contributories to the brain, yet leave the left vertebral artery unprotected. METHODS: Patients underwent TAVR with complete TCEP. A dual-filter system was deployed in the brachiocephalic trunk and left common carotid artery with an additional single filter in the left vertebral artery. After TAVR all filters were retrieved and sent for histopathological evaluation by an experienced pathologist. RESULTS: Eleven patients received a dual-filter system and nine of them received an additional left vertebral filter. In the remaining two patients, the left vertebral filter could not be deployed. No periprocedural strokes occurred. We found debris in all filters, consisting of thrombus, tissue derived debris, and foreign body material. The left vertebral filter contained debris in an equal amount of patients as the Sentinel filters. The size of the captured particles was similar between all filters. CONCLUSIONS: The left vertebral artery is an important entry route for embolic material to the brain during TAVR. Selective filter protection of the left vertebral artery revealed embolic debris in all patients. The clinical value of complete filter-based TCEP during TAVR warrants further research.

Conduction dynamics after transcatheter aortic valve implantation and implications for permanent pacemaker implantation and early discharge: the CONDUCT-study.

Aims: To correlate dynamics in electrical conduction after transcatheter aortic valve implantation (TAVI) with need for permanent pacemaker implantation (PPM) and assess implications for early discharge. Methods and results: Daily electrocardiograms after TAVI were analysed for rhythm and conduction times and were correlated with PPM. Transcatheter aortic valve implantation was performed in 291 consecutive patients with three contemporary transcatheter heart valve designs: Medtronic CoreValve (n = 111), Edwards Sapien XT (n = 29) and Sapien 3 (n = 72), and Boston Lotus (n = 79). We considered two cohorts: (A) Patients with normal baseline conduction; and (B) patients with pre-existent conduction disturbances. Based on QRS dynamics, three patterns were discerned: stable normal QRS duration, transient QRS prolongation, and persistent QRS prolongation. In Cohort B, QRS dynamics did not correlate with PPM. In contrast, in Cohort A, QRS dynamics and PPM appeared highly correlated. Neither patients with stable normal QRS duration (0/47), nor patients with transient QRS prolongation required PPM (0/26). All PPMs occurred in patients with persistent QRS prolongation until discharge (27/85). Persistent QRS prolongation was typically seen with Lotus and CoreValve, whereas stable normal QRS duration was typically seen with Sapien XT and Sapien 3. Conclusion: Three distinct patterns of QRS dynamics can be discerned after TAVI and their predictive probabilities for PPM strongly relate to the baseline conduction status. Patients with normal conduction at baseline and stable QRS duration after TAVI are potentially eligible for early discharge.

Electrocardiographic imaging-based recognition of possible induced bundle branch blocks during transcatheter aortic valve implantations.

AIMS: Conventional electrocardiogram (ECG)-based diagnosis of left bundle branch block (LBBB) in patients with left ventricular hypertrophy (LVH) is ambiguous. Left ventricular hypertrophy is often seen in patients with severe aortic stenosis in which a transcatheter aortic valve implantation (TAVI) frequently results in a LBBB due to the mechanical interaction of the artificial valve and the conduction system. In this feasibility study, we propose and evaluate the sensitivity of a new electrocardiographic imaging tool; the cardiac isochrone positioning system (CIPS), visualizing the cardiac activation to detect interventricular conduction patterns pre- and post-TAVI. METHODS AND RESULTS: The CIPS translates standard 12-lead ECG into ventricular isochrones, representing the activation sequence. It requires a patient-specific model integrating heart, lungs, and other thoracic structures derived from multi-slice computed tomography. The fastest route-based algorithm was used to estimate the activation isochrones and the results were compared with standard ECG analysis. In 10 patients the CIPS was used to analyse 20 ECGs, 10 pre- and 10 post-TAVI. In 11 cases the CIPS results were in agreement with the ECG-based diagnosis. In two cases there was partial agreement and in seven cases there was disagreement. In four of these cases, the clinical history of the patients favoured interpretation as assessed by CIPS, for the remaining three, it is unknown which method correctly classified the activation. CONCLUSION: This feasibility study applying the CIPS shows promising results to classify conduction disorders originating from the left anterior or posterior ventricular wall, or the septum. The visualization of the activation isochrones as well as ventricular model-derived features might support TAVI procedures and the therapy selection afterwards.

Timing and potential mechanisms of new conduction abnormalities during the implantation of the Medtronic CoreValve System in patients with aortic stenosis.

AIMS: New-onset left bundle branch block (LBBB) and complete atrioventricular block (AV3B) frequently occur following transcatheter aortic valve implantation (TAVI). We sought to determine the timing and potential mechanisms of new conduction abnormalities (CAs) during TAVI, using the Medtronic CoreValve System (MCS). METHODS AND RESULTS: Sixty-five consecutive patients underwent TAVI with continuous 12-lead ECG analysis. New CAs were defined by the occurrence of LBBB, RBBB, and/or AV3B after the following pre-defined time points: (i) crossing of valve with stiff wire, (ii) positioning of balloon catheter in the aortic annulus, (iii) balloon valvuloplasty, (iv) positioning of MCS in the left ventricular outflow tract (LVOT), (v) expansion of MCS, (vi) removal of all catheters. A new CA occurred during TAVI in 48 patients (74%) and after TAVI in 5 (8%). Of the 48 patients with procedural CAs, a single new CA occurred in 43 patients (90%) and two types of CAs in 5 (10%). A new LBBB was seen in 40 patients (83%), AV3B in 9 (19%), and RBBB in 4 (8%). The new CA first occurred-in descending order of frequency-after balloon valvuloplasty in 22 patients (46%), MCS expansion in 14 (29%), MCS positioning in 6 (12%), positioning of balloon catheter in 3 (6%), wire-crossing of aortic valve in 2 (4%), and after catheter removal in 1 patient (2%). Patients who developed a new CA during balloon valvuloplasty had a significantly higher balloon/annulus ratio than those who did not (1.10±0.10 vs. 1.03±0.11, P=0.030). No such relationship was found with the valve/annulus ratio. CONCLUSION: Transcatheter aortic valve implantation with the MCS was associated with new CAs in 82% of which more than half occurred before the actual valve implantation. It remains to be elucidated by dedicated studies whether new CAs can be reduced by appropriate balloon sizing-a precept that also holds for valve size given the observed directional signal of the valve size/aortic annulus ratio.

Impact of Baseline and Newly Acquired Conduction Disorders on Need for Permanent Pacemakers With 3 Consecutive Generations of Self-Expanding Transcatheter Aortic Heart Valves.

INTRODUCTION: We aimed to compare conduction dynamics and need for permanent pacemaker implantation (PPI) after CoreValve, Evolut R and PRO (transcatheter aortic valve replacement (TAVR)). METHODS: Patients were stratified based on conduction at baseline; Cohort A had normal conduction, Cohort B had conduction abnormalities including atrioventricular (AV)-block, fascicular block or complete bundle branch block. Three different dynamic QRS-patterns were defined: stable QRS-duration, transient QRS-prolongation and persistent QRS-prolongation. We performed multivariable regression analysis to estimate the effect of the three separate transcatheter heart valves (THV's) on need for PPI at 30 days. RESULTS: TAVR was performed with CoreValve (N = 113), Evolut R (N = 157) or Evolut PRO (N = 92). Conduction dynamics were similar between the different THVs. Overall, Evolut R and PRO showed a tendency towards less PPI compared to CoreValve (17% vs. 19% vs. 27%, P = 0.08), which was driven by a lower PPI rate in Cohort A (6% vs. 11% vs. 25%, P = 0.002). Need for PPI was restricted to patients with persistent QRS-prolongation in Cohort A (26/106) but did not correlate with conduction dynamics in Cohort B. In multivariable logistic regression analysis the use of Evolut R (OR 0.38, 95% CI 0.19-0.78, P = 0.008) and PRO (OR 0.41, 95% CI 0.19-0.91, P-value = 0.028) were independently associated with less need for PPI. CONCLUSION: The newer generations Evolut R and PRO were associated with less PPI compared to CoreValve. Acquired persistent conduction abnormalities predicted PPI after TAVR only in patients with normal conduction at baseline. Our findings may help identify eligible patients for early discharge after Evolut R/PRO TAVR.

Design and principle of operation of the HeartMate PHP (percutaneous heart pump).

The HeartMate PHP (percutaneous heart pump) is a second-generation transcatheter axial flow circulatory support system. The collapsible catheter pump is inserted through a 14 Fr sheath, deployed across the aortic valve expanding to 24 Fr and able to deliver up to 5 L/min blood flow at minimum haemolytic risk. As such, this device may be a valuable adjunct to percutaneous coronary intervention (PCI) of challenging lesions in high-risk patients or treatment of cardiogenic shock. This technical report discusses: (i) the HeartMate PHP concept, (ii) the implantation technique, (iii) the haemodynamic performance in an in vitro cardiovascular flow testing set-up, and (iv) preliminary clinical experience. An update on the device, produced by St. Jude Medical/Abbott Laboratories, can be found in the Appendix.

Pulsatile iVAC 2L circulatory support in high-risk percutaneous coronary intervention.

AIMS: Our aim was to test the feasibility and safety of the transfemoral PulseCath iVAC 2L (PulseCath, Amsterdam, The Netherlands). METHODS AND RESULTS: Circulatory support devices are helpful adjunctive tools to perform high-risk percutaneous coronary interventions (PCI). The PulseCath iVAC 2L is a novel pulsatile circulatory support system capable of generating output of up to 2 L/min. We performed a prospective clinical pilot study enrolling 14 patients who underwent high-risk PCI under protection with the iVAC 2L. Median age was 74 (56-84) years. Implantation of the iVAC 2L was successful in 13 (93%) patients. Median device flow was 1.4 (1.1-2.0) L/min. Total support time was 67 (23-149) minutes. The use of iVAC 2L support was associated with a better mean arterial pressure and cardiac output during the procedure. Angiographic success was 100%. There was one major procedural complication related to the 19 Fr access sheath. There were no major adverse events at three-month follow-up. CONCLUSIONS: Circulatory support with the iVAC 2L device is feasible and safe in patients undergoing high-risk PCI.

Determinants of image quality of rotational angiography for on-line assessment of frame geometry after transcatheter aortic valve implantation.

To study the determinants of image quality of rotational angiography using dedicated research prototype software for motion compensation without rapid ventricular pacing after the implantation of four commercially available catheter-based valves. Prospective observational study including 179 consecutive patients who underwent transcatheter aortic valve implantation (TAVI) with either the Medtronic CoreValve (MCS), Edward-SAPIEN Valve (ESV), Boston Sadra Lotus (BSL) or Saint-Jude Portico Valve (SJP) in whom rotational angiography (R-angio) with motion compensation 3D image reconstruction was performed. Image quality was evaluated from grade 1 (excellent image quality) to grade 5 (strongly degraded). Distinction was made between good (grades 1, 2) and poor image quality (grades 3-5). Clinical (gender, body mass index, Agatston score, heart rate and rhythm, artifacts), procedural (valve type) and technical variables (isocentricity) were related with the image quality assessment. Image quality was good in 128 (72 %) and poor in 51 (28 %) patients. By univariable analysis only valve type (BSL) and the presence of an artefact negatively affected image quality. By multivariate analysis (in which BMI was forced into the model) BSL valve (Odds 3.5, 95 % CI [1.3-9.6], p = 0.02), presence of an artifact (Odds 2.5, 95 % CI [1.2-5.4], p = 0.02) and BMI (Odds 1.1, 95 % CI [1.0-1.2], p = 0.04) were independent predictors of poor image quality. Rotational angiography with motion compensation 3D image reconstruction using a dedicated research prototype software offers good image quality for the evaluation of frame geometry after TAVI in the majority of patients. Valve type, presence of artifacts and higher BMI negatively affect image quality.

Does frame geometry play a role in aortic regurgitation after Medtronic CoreValve implantation?

AIMS: Aortic regurgitation (AR) after Medtronic CoreValve System (MCS) implantation may be explained by patient-, operator- and procedure-related factors. We sought to explore if frame geometry, as a result of a specific device-host interaction, contributes to AR. METHODS AND RESULTS: Using rotational angiography with dedicated motion compensation, we assessed valve frame geometry in 84 patients who underwent TAVI with the MCS. Aortic regurgitation was assessed by angiography (n=84, Sellers) and echocardiography at discharge (n=72, VARC-2). Twenty-two patients (26%) had AR grade ≥2 using contrast angiography, and 17 (24%) by echocardiography. Balloon predilatation and sizing and depth of implantation did not differ between the two groups. Despite more frequent balloon post-dilatation in patients with AR (40.9 vs. 9.7%, p=0.001), the frame was more elliptical at its nadir relative to the patient's annulus (6±13 vs. -1±11%, p=0.046) and occurred in a larger proportion of patients (61.9 vs. 26.8%, p=0.004). Although the Agatston score and the eccentricity of the MCS frame relative to the annulus were independent determinants of AR (odds ratio: 1.635 [1.151-2.324], p=0.006, and 4.204 [1.237-14.290], p=0.021), there was a weak association between the Agatston score and the adjusted eccentricity (Spearman's rank correlation coefficient =-0.24, p=0.046). CONCLUSIONS: These findings indicate that AR can be explained by a specific device-host interaction which can only partially be explained by the calcium load of the aortic root.

Early and persistent intraventricular conduction abnormalities and requirements for pacemaking after percutaneous replacement of the aortic valve.

OBJECTIVES: In this retrospective study, we examined the incidence of post-procedural conduction abnormalities and the need for pacing in patients undergoing percutaneous implantation of the aortic valve. BACKGROUND: Safety and feasibility studies have suggested anecdotally the occurrence of conduction abnormalities and requirements for pacing after percutaneous implantation of the aortic valve. METHODS: We examined the standard 12-lead electrocardiograms (ECGs) of 40 consecutive patients in whom a CoreValve Revalving System (CoreValve, Paris, France) was implanted between November 2005 and March 2008. We examined the 12-lead ECG before treatment, after treatment, and at 1-month follow-up. We documented the requirements for temporary or permanent pacemaking. RESULTS: The mean age of patients was 82 +/- 7 years. Post-procedural mortality at 72 h was 0%. There was a significant increase in the frequency of left bundle branch block (LBBB) after percutaneous aortic valve replacement (15% before treatment vs. 55% after treatment, p = 0.001). Although the incidence of LBBB had decreased after follow-up of 1 month, it did not reach statistical significance, with the proportion decreasing from 55% to 48% (p = 0.63). The only 2 patients with pre-treatment right bundle branch block became dependent on temporary pacing immediately after valve implantation and subsequently needed permanent pacing. A temporary and permanent pacemaker was required in 20% and 18% of patients, respectively. CONCLUSIONS: In this study, there was a significant increase in the frequency of LBBB after percutaneous insertion of the aortic valvar prosthesis. Patients with pre-existing right bundle branch block may be at risk for the development of complete heart block and subsequent need for pacing.

In vivo validation of a novel three-dimensional quantitative coronary angiography system (CardiOp-B): comparison with a conventional two-dimensional system (CAAS II) and with special reference to optical coherence tomography.

AIMS: To validate a novel 3-D QCA system (CardiOp-B) and compare the 2-D (CAAS II) and 3-D systems in in vivo experimental settings. The phantom lumen diameters were also assessed ex vivo by optical coherence tomography (OCT). The accuracy of the 3-D system has not been appreciated. METHODS AND RESULTS: Precision-drilled plexiglass phantoms with 5 different luminal diameters that ranged from 0.5 to 1.9 mm were percutaneously inserted into the coronary arteries in four Yorkshire pigs. Twenty-two angiographic images of the artificial phantom coronary artery stenoses in the pigs were acquired as an in vivo validation test. Quantitative assessments of the minimum and mean lumen diameters were performed using both QCA systems. Ex vivo images of the same phantom lumens were also taken and measured using OCT.Both of the 2-D and 3-D QCA systems significantly underestimated the actual phantom lumen diameters with the exception of measurements taken in the lateral projection at isocenter using the 2-D QCA systems. This underestimation was more significant in the 3-D system (accuracy of 0.19 at isocenter; 0.23 by catheter calibration). There was good agreement between the two QCA systems. OCT measured the ex vivo lumen diameter of plexiglass phantoms precisely. CONCLUSIONS: The accuracy of the luminal diameter measurements with the current 2-D system was still superior to the 3-D system. Further development and validation studies under various conditions are warranted. The excellent results achieved by OCT with the ex vivo images indicate its potential as an intravascular quantitative imaging tool for future clinical practice.