Faculty Bibliography

INTRODUCTION/BACKGROUND:The membranous septum (MS) length measured by cardiac computed tomography (CT) is useful for the prediction of permanent pacemaker implantation (PPMI) and new left bundle branch block (LBBB) after transcatheter aortic valve replacement. However, its predictive value for patients undergoing surgical aortic valve replacement (SAVR) is unknown. METHODS:A total of 2531 consecutive patients were registered in the institutional Society of Thoracic Surgeons database between July 2017 and June 2020. Patients who underwent non-SAVR procedures, had prior pacemaker/implantable cardioverter defibrillator, prior SAVR, no preprocedural CT assessment, or suboptimal CT imaging were excluded. RESULTS:(odds ratio: 9.165; 95% confidence interval: 1.644-51.080; P = 0.011) and MS length <1.5 mm (odds ratio: 14.449; 95% confidence interval: 1.632-127.954; P = 0.016) were independent predictors for new PPMI/LBBB. CONCLUSIONS:Short MS length on preoperative cardiac CT is a powerful and novel predictor for the risk of new PPMI/LBBB after SAVR. Special care should be taken in patients with short MS length to avoid suture-mediated trauma.

Coronary artery obstruction caused by sinus sequestration is well described after transcatheter aortic valve implantation in failed bioprosthetic valves, which usually occurs during or shortly after the transcatheter aortic valve implantation procedure. We report the presentation, management, and outcomes of 2 cases of very late sinus sequestration in native aortic annuli, which has not been described before to our knowledge. (Level of Difficulty: Advanced.).

Background: Limited data exist on the use of temporary permanent pacemaker (TPPM) to reduce unnecessary PPM in patients with high-degree atrioventricular block (HAVB) after transcatheter aortic valve replacement (TAVR). Objectives: This study aims to determine the feasibility of TPPM in patients with HAVB after TAVR to provide prolonged pacing as a bridge. Materials and methods: One hundred and eleven consecutive patients undergoing TAVR were screened from August 2021 to June 2022. Patients with HAVB eligible for PPM were included. TPPM were used in these patients instead of conventional temporary pacing or early PPM. Patients were followed up for 1 month. Holter and pacemaker interrogation were used to determine whether to implant PPM. Results: Twenty one patients met the inclusion criteria for TPPM, of which 14 patients were third-degree AVB, 1 patient was second-degree AVB, 6 patients were first degree AVB with PR interval > 240 ms and LBBB with QRS duration > 150 ms. TPPM were placed on the 21 patients for 35 ± 7 days. Among 15 patients with HAVB, 26.7% of them (n = 4) recovered to sinus rhythm; 46.7% (n = 7) recovered to sinus rhythm with bundle branch block. The remains of 26.7% patients (n = 4) still had third-degree AVB and received PPM. For patients with first-degree AVB and LBBB, PR interval shortened to < 200 ms in all 6 patients and LBBB recovered in 2 patients. TPPM were successfully removed from all patients and no procedure-related adverse events occurred. Conclusion: TPPM is reliable and safe in the small sample of patients with conduction block after TAVR to provide certain buffer time to distinguish whether a PPM is necessary. Future studies with larger sample are needed for further validation of the current results.

Indications for transcatheter aortic valve implantation (TAVI) have expanded in many countries to include patients with aortic stenosis who are at low surgical risk, and a similar expansion to this cohort is anticipated elsewhere in the world, together with an increase in the proportion of patients with bicuspid aortic valve (BAV) morphology as the age of the patients being treated decreases. To date, patients with BAV have been excluded from major randomized trials of TAVI owing to anatomical considerations. As a consequence, BAV has been a relative contraindication to the use of TAVI in international guidelines. Although clinical experience and observational data are accumulating, BAV presents numerous anatomical challenges for successful TAVI, despite advances in device design. Furthermore, in those with BAV, substantial geographical variation exists in patient characteristics, clinical approach and procedural strategy. Therefore, in this Roadmap article, we summarize the existing evidence and provide consensus recommendations from an international group of experts on the application of TAVI in patients with BAV in advance of the anticipated growth in the use of this procedure in this challenging cohort of patients.

BACKGROUND:The study aimed to describe the aortic valve morphology in Chinese patients underwent transcatheter aortic valve replacement (TAVR) for symptomatic severe aortic stenosis (AS), and the impact of sizing strategies and related procedural outcomes. METHODS:Patients with severe AS who underwent TAVR were consecutively enrolled from 2012 to 2019. The anatomy and morphology of the aortic root were assessed. "Downsize" strategy was preformed when patients had complex morphology. The clinical outcomes of patients who performed downsize strategy were compared with those received annular sizing strategy. The primary outcome was device success rate, and secondary outcomes included Valve Academic Research Consortium-3 clinical outcomes variables based on 1-year follow-up. RESULTS:A total of 293 patients were enrolled. Among them, 95 patients (32.4%) had bicuspid aortic valve. The calcium volume (Hounsfield Unit-850) of aortic root was 449.90 (243.15-782.15) mm 3 . Calcium is distributed mostly on the leaflet level. Downsize strategy was performed in 204 patients (69.6%). Compared with the patients who performed annular sizing strategy, those received downsize strategy achieved a similar device success rate (82.0% [73] vs . 83.3% [170], P  = 0.79). Aortic valve gradients (downsize strategy group vs . annular sizing group, 11.28 mmHg vs. 11.88 mmHg, P  = 0.64) and percentages of patients with moderate or severe paravalvular regurgitation 2.0% (4/204) vs . 4.5% (4/89), P  = 0.21) were similar in the two groups at 30 days after TAVR. These echocardiographic results were sustainable for one year. CONCLUSIONS:Chinese TAVR patients have more prevalent bicuspid morphology and large calcium volume of aortic root. Calcium is distributed mostly on the leaflet level. Compare with annular sizing strategy, downsize strategy provided a non-inferior device success rate and transcatheter heart valve hemodynamic performance in self-expanding TAVR procedure.

ReAces is a novel puncturable transcatheter atrial septal defect occluder. The device success rate was 100% (n = 14 of 14) in the animal experiment. Four swine successfully received puncture of the device 60 days after implantation of the device. The acute procedure success rate in the 10 patients was 100%. Transthoracic echocardiography examination showed that the devices were well positioned with no residual shunt, and the area of central portion of occluder was substantially thin. It is safe and effective to use ReAces for closure of secundum atrial septal defect, and puncture the atrial septum at the portion of the device is feasible.

BACKGROUND:Success rate of transcatheter aortic valve replacement (TAVR) in aortic regurgitation (AR) patients is relatively low on account of the absence of calcified anchoring structures. Morphological classification and corresponding TAVR strategies for AR are lacking yet. METHODS:The AURORA study is a prospective, multicenter, single-arm cohort study to evaluate the safety and efficacy of transfemoral TAVR for severe AR in patients with high or prohibitive risk for surgery. Patients who are ≥ 65 years and diagnosed with severe pure AR as defined by the Echocardiographic Core Laboratory will be consecutively enrolled for further multidetector computed tomography (MDCT) scanning and multiplanar analyses. Based on a new anatomical classification and dual anchoring theory, patients will be classified into 4 types according to the level of the anchoring area. Types 1, 2 and 3 (at least 2 anchoring areas) will undergo the TAVR procedure with a domestic Chinese self-expanding valve (VitaFlow Valve, MicroPort, Shanghai, China), whereas type 4 (0 or 1 anchoring area) patients will be considered unsuitable for TAVR and will receive medical treatment. Our goal is to recruit 100 patients to account for 10% missing data or loss of patients to follow-up. Procedural, 30-day, 6-month and 12-month outcomes will be assessed according to Valve Academic Research Consortium-3 criteria. DISCUSSION:The AURORA study will establish a new AR anatomical classification based on dual anchoring theory through MDCT multiplanar measurement and assess the safety and efficacy of TAVR guided by this new classification and strategy in AR patients. TRIAL REGISTRATION:This Study was registered at Chinses Clinical Trial Registry. The registration number: ChiCTR2200055415; The date of registration: 9, January 2022; The URL of the registration: http://www.chictr.org.cn/showproj.aspx?proj=141209 .

Herein we present a case of an 80-year-old gentleman who presented with exertional dyspnea status post aortic valve replacement with #23 Trifecta pericardial St. Jude aortic bioprosthetic valve (BV) 12 years prior. He subsequently underwent valve re-replacement due cusp calcification. Histologically, the surgically explanted BV revealed Congophilic deposits with birefringence under cross-polarized light. Extensive work-up identified no systemic source of amyloid in this patient. Liquid chromatography-tandem mass spectrometry-based (LC-MS/MS) proteomics showed the amyloid was composed of human-origin amyloid signature proteins (apolipoprotein A4, apolipoprotein E, serum amyloid P) and human-origin mu heavy chains. Background bovine collagen was also present. Transmission electron microscopy (TEM) showed collections of 7.5-10 nm nonbranching fibrils, consistent with amyloid. Using these techniques, we classified the amyloid as Mu heavy chain, deposition of which is highly unusual in BV. Finally, we provide a review of the literature regarding isolated amyloid deposition in BV.

A virtual workshop was organized by the Heart Valve Collaboratory to identify areas of expert consensus, areas of disagreement, and evidence gaps related to bioprosthetic aortic valve hemodynamics. Impaired functional performance of bioprosthetic aortic valve replacement is associated with adverse patient outcomes; however, this assessment is complicated by the lack of standardization for labelling, definitions, and measurement techniques, both after surgical and transcatheter valve replacement. Echocardiography remains the standard assessment methodology because of its ease of performance, widespread availability, ability to do serial measurements over time, and correlation with outcomes. Management of a high gradient after replacement requires integration of the patient's clinical status, physical examination, and multimodality imaging in addition to shared patient decisions regarding treatment options. Future priorities that are underway include efforts to standardize prosthesis sizing and labelling for both surgical and transcatheter valves as well as trials to characterize the consequences of adverse hemodynamics.