Frequency of conduction disturbances after transcatheter implantation of an Edwards Sapien aortic valve prosthesis

Conduction dynamics over time after transcatheter aortic valve replacement: An expert review

New conduction disorders remain a frequent complication in current transcatheter aortic valve replacement (TAVR) era. Left bundle branch block (LBBB) occurs early in about 20-30 % of TAVR-patients, persists at 1 month in about 35-45 % of cases and will likely remain thereafter. Third-degree atrioventricular block (AV3B) affects approximately 15 % of patients. Pacemaker dependency gradually decreases throughout follow-up and approximately 25-35 % of patients remain pacemaker dependent at one year. We aimed to review what is currently known about the dynamics of acquired conduction disorders, including extraction of predictors, and how to interpret these dynamics in light of an early discharge policy.

Predictors of New and Persistent New Left Bundle Branch Block One Year after the Implantation of a Sutureless and Rapid-Deployment Aortic Valve Prosthesis

INTRODUCTION

Conduction disorders following aortic valve replacement therapy (AVR), either surgical or percutaneous, are related to a higher risk of complete atrioventricular block and permanent pacemaker implantation (PPI).

AIM

The objective of this study was to assess risk factors regarding the incidence of new postoperative and persistent new left bundle branch block (LBBB) 1 year after the implantation of a sutureless/rapid-deployment (SURD) aortic valve prosthesis.

MATERIAL AND METHODS

The current study included 200 consecutive patients treated with isolated or concomitant AVR between May 2014 and May 2017 at the Department of Cardiac Surgery in Pasawa with SURD aortic valve EDWARDS INTUITY EliteTM implantation. The patients were divided according to the presence of new postoperative LBBB (67 patients, 33.5%) and persistent new LBBB 1 year after AVR (35 patients, 17.5%). A comparative analysis was performed between patients with and without new LBBB after AVR and those with and without persistent LBBB 1 year after AVR. Univariate and multivariate regression analyses were conducted to extract the risk factors of LBBB occurrence.

RESULTS

Among the risk factors for the lack of new LBBB development after AVR, Euroscore II (p < 0.001) was found, while for the occurrence of persistent new LBBB 1 year after AVR, atrial fibrillation (p = 0.001), length of hospital stay (p = 0.001) and body mass index (p = 0.004) were noted.

CONCLUSIONS

Patients with new or persistent new LBBB 1 year after AVR had lower mean Euroscore II and BMI values. Their stay at the hospital was also shorter.

Impact of New-Onset Conduction Disturbances following Transcatheter Aortic Valve Replacement on Outcomes: A Single-Center Study

Background

Transcatheter aortic valve replacement (TAVR) is known to increase the incidence of conduction disturbances compared to surgical aortic valve replacement; however, there are limited data on the impact and duration of these conduction disturbances on longer term outcomes.

Objective

To determine the differential impact of persistent versus nonpersistent new-onset conduction disturbances on TAVR-related complications and outcomes.

Methods

This is a single-center retrospective analysis of 927 consecutive patients with aortic stenosis who underwent TAVR at Yale New Haven Hospital from July 2012 to August 2019. Patients with new-onset conduction disturbances within 7 days following TAVR were selected for this study. Persistent and nonpersistent disturbances were, respectively, defined as persisting or not persisting on all patient ECGs for up to 1.5 years after TAVR or until death.

Results

Within 7 days after TAVR, conduction disturbances occurred in 42.3% (392/927) of the patients. Conduction disturbances persisted in 150 (38%) patients and did not persist in 187 (48%) patients, and 55 (14%) patients were excluded for having mixed (both persistent and nonpersistent) disturbances. Compared with nonpersistent disturbances, patients with persistent disturbances were more likely to receive a PPM within 7 days after the TAVR procedure (46.0% versus 4.3%, p < 0.001) and had a greater unadjusted 1-year cardiac-related and all-cause mortality risk (HR 2.54, p=0.044 and HR 1.90, p=0.046, respectively).

Conclusion

Persistent conduction disturbances were associated with a greater cardiac and all-cause mortality rate at one year following TAVR. Future research should investigate periprocedural factors to reduce persistent conduction disturbances and outcomes beyond one year follow-up.

A single-centre cohort and short-term follow-up of patients who developed persistent new onset left bundle branch block after transcatheter aortic valve replacement

Background: The most common conduction abnormality after transcatheter aortic valve replacement (TAVR) is new-onset left bundle branch block (LBBB) with an exact frequency that varies based on the valve system used for TAVR. PPM implantation in patients with persistent new onset LBBB post TAVR is controversial. The primary objective of this study is to report PPM utilisation and mortality in this patient population.Methods: A TAVR registry included patients older than 18 years who underwent TAVR between March 2012 and June 2015 at University of Minnesota Medical Centre. After exclusion, 151 patients were divided into two groups; patients with persistent new onset LBBB after TAVR (new LBBB, n = 47) and patients without persistent new onset LBBB (no new LBBB, n = 104).Results: Among the 151 patients, 47 (31.1%) patients developed new-onset LBBB after the procedure and persisted at discharge. Left ventricular ejection fraction (LVEF) (52.5 ± 11.1 vs. 56.4 ± 10.8, p: .047) and mean aortic valve gradient (40.6 ± 11.5 vs. 45.7 ± 14.1, p: .022) were significantly higher in no new LBBB group. Among those with new LBBB, there was a significantly higher rate of PPM implant during index hospitalisation (14.9%, vs. 0%, p < .001). LVEF remained significantly lower at 1 year follow up in new LBBB group compared to no new LBBB group (51.8 ± 11.2 vs. 57.6 ± 8.3, p: .002). Also in new LBBB group, there was a non-significantly higher rate of all-cause mortality in 1 year compared to no new LBBB group (14.9% vs. 9.6% p: .34). There were no significant differences between patients with and without new LBBB with respect to PPM implant after discharge in 1 year (2.13% vs. 3.8% p: .58), length of stay (7.3 ± 7.3 vs. 5.9 ± 2.7 p: .09), post-op atrial fibrillation (AF) (16.3% vs. 8.5% p: .20).Conclusions: New onset LBBB was frequent conduction problem post TAVR and one-third of patients with new onset LBBB persisted at discharge. New LBBB after TAVR was associated with a higher risk of PPM implantation during the index hospitalisation but not after discharge. Our findings suggest that early PPM implantation for post-TAVR LBBB is not indicated without complete or high degree AV block. Further research is required to identify the patients with new LBBB who would progress to advanced AV block or heart failure.

Importance of Preoperative Computed Tomography Assessment of the Membranous Septal Anatomy in Patients Undergoing Transcatheter Aortic Valve Replacement With a Balloon-Expandable Valve

BACKGROUND

Cardiac conduction disturbance (CD) is the most frequent complication following transcatheter aortic valve replacement (TAVR). This study examined whether the anatomy of the membranous septum (MS) could provide useful information about the risk of CD following TAVR with a balloon-expandable valve (BEV).

METHODS AND RESULTS

Among 132 consecutive patients, 106 (mean age, 85.6±5.1 years; 75 females) were included in the study. Using preoperative CT and angiography, MS length and implantation depth (ID) were assessed. The MS length minus the prosthesis ID was calculated (∆MSID). Correlation between CD, defined as new-onset left-bundle branch block (LBBB) or the need for permanent pacemaker (PPM) within 1 week after the procedure, and MS length were evaluated. A total of 19 patients (18%) developed CD following TAVR. MS length was significantly shorter in these patients than in those without CD (5.3±1.3 vs. 6.6±1.4; P<0.001), and was the important predictor of CD (odds ratio [OR]: 0.43, 95% confidence interval [CI]: 0.27-0.69, P<0.001). When considering the pre- and postprocedural parameters, the ∆MSID was smaller in patients with CD (-1.7±1.5 vs. 0.8±1.9, P<0.001), and emerged as the important predictor of CD (OR: 0.47, 95% CI: 0.33-0.69, P<0.001).

CONCLUSIONS

Short MS is associated with an increased risk of CD after TAVR with BEV.

Complications after Transfemoral Transcatheter Aortic Valve Replacement with a Balloon-Expandable Prosthesis: The Importance of Preventative Measures and Contingency Planning

Transcatheter aortic valve replacement (TAVR) with balloon-expandable Edwards-SAPIEN valve was superior to standard therapy in inoperable patients and noninferior to surgical aortic valve replacement in high surgical-risk, but operable patients, with severe symptomatic aortic stenosis in the randomized controlled PARTNER trial. Since the first case of TAVR with a balloon-expandable valve in 2002, several groups have reported their experience with balloon-expandable valves with high-procedural success. In the United States, the balloon-expandable Edwards-SAPIEN valve is the only transcatheter heart valve approved by the FDA for commercial use. Moreover, this is only in high-risk inoperable patients. Despite increasing experience with the TAVR procedure, it can be associated with complications, which can be technically challenging, even for an experienced operator. Complications associated with TAVR include vascular complications, valve malpositioning, regurgitation, embolization, coronary compromise, conduction abnormalities, stroke/transient ischemic attack, acute kidney injury, cardiac tamponade, and hemodynamic collapse. A thorough understanding of the procedure is essential for pre-emptive planning for procedural complications and early identification and management of complications are necessary for procedural success. We hereby review our experience of transfemoral TAVR with balloon-expandable valves, offer practical tips to maximize the likelihood of procedural success, describe pre-emptive strategies to prevent peri-procedural complications and bailout measures to manage them, should they occur. © 2018 Wiley Periodicals, Inc.

New-onset left bundle branch block after transcatheter aortic valve replacement is associated with adverse long-term clinical outcomes in intermediate-risk patients: an analysis from the PARTNER II trial

Aims

Transcatheter aortic valve replacement (TAVR) is now an established therapy for intermediate-risk surgical candidates with symptomatic, severe aortic stenosis. The clinical impact of new-onset left bundle branch block (LBBB) after TAVR remains controversial and has not been studied in intermediate-risk patients. We therefore sought to analyse outcomes associated with new LBBB in a large cohort of intermediate-risk patients treated with TAVR.

Methods and results

A total of 2043 patients underwent TAVR in the PARTNER II trial and S3 intermediate-risk registry and survived to hospital discharge. Patients were excluded from the current analysis due to baseline conduction disturbances, pre-existing permanent pacemaker (PPM), and new PPM during the index hospitalization. Clinical outcomes at 2 years were compared between patients with and without persistent, new-onset LBBB at hospital discharge, and multivariable analysis was performed to identify predictors of mortality. Among 1179 intermediate-risk patients, new-onset LBBB at discharge occurred in 179 patients (15.2%). Patients with new LBBB were similar to those without except for more frequent diabetes and more frequent treatment with SAPIEN 3 vs. SAPIEN XT. At 2 years, new LBBB was associated with increased rates of all-cause mortality (19.3% vs. 10.8%, P = 0.002), cardiovascular mortality (16.2% vs. 6.5%, P < 0.001), rehospitalization, and new PPM implantation. By multivariable analysis, new LBBB remained an independent predictor of 2-year all-cause [hazard ratio (HR) 1.98, 95% confidence interval (95% CI) 1.33, 2.96; P < 0.001] and cardiovascular (HR 2.66 95% CI 1.67, 4.24; P < 0.001) mortality. New LBBB was also associated with worse left ventricular systolic function at 1 and 2-year follow-up.

Conclusions

In a large cohort of intermediate-risk patients from the PARTNER II trial and registry, persistent, new-onset LBBB occurred in 15.2% of patients without baseline conduction disturbances or pacemaker. New LBBB was associated with adverse clinical outcomes at 2 years, including all-cause and cardiovascular mortality, rehospitalization, new pacemaker implantation, and worsened left ventricular systolic function.

Clinical Trial Registration

ClinicalTrials.gov #NCT01314313 and NCT03222128.

Conduction Abnormalities After Transcatheter Aortic Valve Replacement

Transcatheter aortic valve replacement (TAVR) has been established as a therapeutic option for patients with severe symptomatic aortic stenosis who are of intermediate or higher surgical risk. Several periprocedural complications are reduced with newer transcatheter heart valve generations; however, conduction abnormalities and the need for permanent pacemaker implantation have remained unchanged and are the most frequent TAVR complications. The close relationship of the atrioventricular node and left bundle branch to the subaortic region explains these potential conduction abnormalities. This article highlights conduction abnormalities after TAVR with a focus on basic conduction system anatomy in relation to the aortic valve, the mechanism, incidence, predisposing factors for occurrence, impact on mortality and finally, proposed treatment algorithms for management.

TAVI and Post Procedural Cardiac Conduction Abnormalities

Transcatheter aortic valve implantation (TAVI) is a worldwide accepted alternative for treating patients at intermediate or high risk for surgery. In recent years, the rate of complications has markedly decreased except for new-onset atrioventricular and intraventricular conduction block that remains the most common complication after TAVI. Although procedural, clinical, and electrocardiographic predisposing factors have been identified as predictors of conduction disturbances, new strategies are needed to avoid such complications, particularly in the current TAVI era that is moving quickly toward the percutaneous treatment of low-risk patients. In this article, we will review the incidence, predictive factors, and clinical implications of conduction disturbances after TAVI.

A Prospective Analysis of Early Discharge After Transfemoral Transcatheter Aortic Valve Implantation

As transcatheter aortic valve implantation (TAVI) becomes more routinely used, the recommended duration of monitoring after uncomplicated TAVI remains indeterminate. Retrospective analysis suggests that discharge within 72 hours is safe, but prospective data are largely lacking. We therefore prospectively assess the feasibility and safety of early discharge (within 72 hours) after transfemoral TAVI using Edwards SAPIEN-XT and SAPIEN-3 prostheses. Patients undergoing elective transfemoral TAVI were assessed prospectively for early discharge home. Feasibility and safety (death or repeat hospitalization within 30 days of discharge) of early discharge were assessed. Causes for failure of early discharge were assessed by prospective data collection and multivariate analysis. Of 130 patients, 76 (59%) were discharged early. Death or repeat hospitalization within 30 days occurred only in 4 cases (5%) among patients who discharged early: repeat hospitalization within 30 days was required in 3 early-discharge patients (4%), and there was a single death at 30 days. By multivariate analysis, factors associated with delayed discharge were blood transfusion (hazard ratio 13.85, 95% CI 1.61 to 119.40, p = 0.017) and pacemaker implantation (hazard ratio 4.47, 95% CI 1.34 to 14.26, p = 0.012). In conclusion, early discharge after elective transfemoral TAVI with SAPIEN-XT/SAPIEN-3 prostheses is safe and attainable in a large proportion of patients, with no evident compromise in safety. Factors associated with failure of early discharge are postprocedural blood transfusion and permanent pacemaker implantation.

One-year follow-up of conduction disturbances following transcatheter aortic valve implantation

AIMS

To describe the postprocedural and 1-year follow-up incidence of heart conduction disturbances in patients with severe symptomatic aortic stenosis undergoing transcatheter aortic valve implantation (TAVI).

METHODS

Ninety-five patients were enrolled from 2008 to 2011 (mean age 81.8 ± 7.2 years, 63.1% women). Clinical and ECG data were recorded at admission, discharge, and 3, 6 and 12 months following TAVI.

RESULTS

Fifty-seven Edwards SAPIEN (31 transapical, 26 transfemoral) and 38 transfemoral CoreValve implants were used. Two (2.1%) patients died during the procedure and 11 (11.6%) patients received a pacemaker prior to discharge (7 CoreValve, 3 transapical, 1 transfemoral SAPIEN; P = 0.18). Among the surviving patients not receiving a pacemaker, TAVI increased the PQ interval (176 ± 29 vs. 188 ± 36 ms; P = 0.001), QRS width (90 ± 15 vs. 108 ± 26 ms; P < 0.001), and first-grade atrioventricular block (17 vs. 29%; P < 0.001). Postprocedural complete left bundle branch block was reported most in transapical (from 10 to 36%; P = 0.01) and CoreValve (from 8 to 64%; P < 0.001) recipients compared to the transfemoral SAPIEN group. At the 12-month follow-up, 24 (25.3%) patients had died [two (2.1%) sudden deaths] and four (4.2%) required pacemaker implantation. Among the survivors not receiving a pacemaker at the 1-year follow-up, the PQ interval (178 ± 27 vs. 188 ± 36 ms; P = 0.39) remained unchanged in the ECG, whereas the QRS width (100 ± 22 vs. 108 ± 26 ms; P = 0.008) decreased compared to measurements taken at discharge.

CONCLUSION

Conduction disturbances following TAVI primarily develop during hospitalization and subsequently stabilize. However, the small percentage of patients suffering sudden death or pacemaker implantation requires attention.

Feasibility and safety of early discharge after transfemoral transcatheter aortic valve implantation with the Edwards SAPIEN-XT prosthesis

There is currently no consensus on the duration of hospitalization required after transfemoral transcatheter aortic valve implantation (TAVI). We report the feasibility and safety of early discharge after TAVI with the Edwards SAPIEN-XT prosthesis. From 2009 to 2013, 337 patients underwent transfemoral TAVI with the Edwards SAPIEN-XT prosthesis using local anesthesia and were discharged home either early (≤3 days, Early Discharge group, n = 121) or after 3 days (Late Discharge group, n = 216). The primary end point of the study combined death and rehospitalization from discharge to 30-day follow-up. Patients in the Early Discharge group were less symptomatic (New York Heart Association class ≥III: 64.5% vs 75.5%, p = 0.01) and had less renal failure (creatinine: 102.1 ± 41.0 vs 113.3 ± 58.9 μmol/L, p = 0.04), atrial fibrillation (33.1% vs 46.3%, p = 0.02), and previous balloon aortic valvuloplasty (11.6% vs 23.1%, p = 0.01) and were more likely to have a pacemaker before TAVI (16.5% vs 8.3%, p = 0.02). Pre-existing pacemaker (p = 0.05) and the absence of acute kidney injury (p = 0.02) were independent predictors of an early discharge, whereas previous balloon aortic valvuloplasty (p = 0.03) and post-TAVI blood transfusions (p = 0.002) were independent predictors of late discharge. The primary end point occurred in 4 patients (3.3%) in the Early Discharge group and in 11 patients (5.1%) in the Late Discharge group (p = 0.58). In conclusion, the results of our study suggest that early discharge after transfemoral TAVI using the Edwards SAPIEN-XT prosthesis is feasible and safe in selected patients.

Cardiac critical care after transcatheter aortic valve replacement

Transcatheter aortic valve replacement (TAVR) is a new therapy for severe aortic stenosis now available in the United States. Initial patients eligible for TAVR are defined by high operative risk, with advanced age and multiple comorbidities. Following TAVR, patients experience acute hemodynamic changes and several possible complications, including hypotension, vascular injury, anemia, stroke, new-onset atrial fibrillation, conduction disturbances and kidney injury, requiring an acute phase of intensive care. Alongside improvements in TAVR technology and technique, improvements in care after TAVR may contribute to improved outcomes. This review presents an approach to post-TAVR critical care and identifies directions for future research.

Evolution of Transcatheter Aortic Valve Replacement

Transcatheter aortic valve replacement emerged ≈20 years ago and changed the landscape of structural interventional cardiology. The first experiments in animal models provided proofs of the concept and the substrate for the first percutaneous valve implantation in patients. The initial promising results in a clinical setting drew the attention of the industry and of the scientific community, and an effort was made for the past 12 years to address the limitations of the technology, facilitate the procedure, minimize the risk of complications, and broaden the applications of transcatheter aortic valve replacement. This article reviews the evolution of transcatheter aortic valve replacement, presents the first steps in this field, cites the evidence from registries and clinical trials, highlights the limitations of this treatment, and discusses the future perspectives and the developments proposed to address the current pitfalls.

TAVI 2012: state of the art

The development of "transcatheter aortic valve implantation (TAVI)" is changing the field of cardiovascular medicine rapidly. The basic principle of TAVI is the percutaneous implantation of a bioprosthesis mounted in a metal frame. The prosthesis, which is attached to the tip of the catheter, is positioned in the native aortic valve and expanded. The first successful implantation was made by Alain Cribier in 2002. Several smaller mono- and multicenter studies later confirmed the technical feasibility of this procedure. Its true value as an important, therapeutic alternative to open heart surgery in inoperable and high-risk patients is now confirmed in large multicenter registries and by the prospective, randomized PARTNER trial. Decisive for the future acceptance of the procedure and for a possible expansion of the indication spectrum will be (1) continuous further development of the implantation technique and the prosthesis design, (2) reduction of TAVI-associated complications, (3) confirmation of the initial positive long-term results and (4) confirmation of the promising results in the treatment of surgical prosthesis dysfunctions and of patients with low to intermediate risk.

An update on complications associated with transcatheter aortic valve implantation: stroke, paravalvular leak, atrioventricular block and perforation

Transcatheter aortic valve implantation (TAVI) has become an alternative therapeutic option for patients with symptomatic severe aortic stenosis at high surgical risk and the standard of care in patients who are inoperable for open aortic valve replacement. With technological evolution and increasing experience, the procedure has become more predictable. Complications of TAVI, however, are not infrequent, and can range from minor to life-threatening events. Stroke, paravalvular leak, various forms of atrioventricular block, including the need for permanent pacemakers and aortic annular and ventricular perforation will be the focus of the present review. Other complications associated with TAVI (such as vascular injury, acute kidney injury, coronary obstruction, valve malpositioning or migration) are clinically important, but are beyond the scope of this article. Understanding the occurrence and pathophysiology of these complications may provide insights into the improvement of the transcatheter devices and techniques, and aid in extending the application of TAVI to a broader population.

Ongoing requirement for pacing post-transcatheter aortic valve implantation and surgical aortic valve replacement

OBJECTIVES

Transcatheter aortic valve implantation (TAVI) is an established intervention for aortic stenosis. While it is known that the requirement for permanent pacing is higher following CoreValve (Medtronic, Inc., Minneapolis, MN, USA) TAVI than after surgical aortic valve replacement (SAVR), it remains uncertain whether pacing is required in the medium-to-long term. We hypothesized that complete heart block following TAVI is more likely to resolve than that following SAVR.

METHODS

A retrospective analysis of prospectively collated data on 528 patients undergoing TAVI or SAVR from May 2008 to December 2010 at a cardiac tertiary referral hospital. Demographic data, timing and indication for pacing post-procedure plus follow-up were recorded. Paced patients were compared and analysed by existing initial indication for pacing.

RESULTS

In total, 31 (5.9%) patients received a pacemaker, and there were limited differences between not paced and paced patient characteristics by procedure type. Of these, a greater proportion were implanted post-TAVI compared with SAVR (17 vs 3.2%, P<0.001). The mean time to pacemaker follow-up for TAVI and SAVR was 234 and 188 days, P=0.32, respectively. Fewer patients compared with pacing indication remained in complete heart block at latest follow-up for TAVI (76.5 vs 33.3%, P=0.02) and SAVR (92.9 vs 58.3%, P=0.04). Although, there was a trend towards a greater magnitude of TAVI patients regaining atrioventricular nodal conduction, this did not differ significantly from that seen in SAVR patients.

CONCLUSIONS

In keeping with previous reports, this single-centre experience demonstrates that patients undergoing TAVI have higher rates of pacemaker implantation than those following SAVR. However, pacing indication in the short-to-medium term may not persist for all paced patients post-TAVI and -SAVR with the suggestion that a significant proportion recover atrioventricular conduction, which tended to be greatest in TAVI paced patients.

Cardiac conduction system disease after transcatheter aortic valve replacement

Transcatheter aortic valve replacement (TAVR) is a rapidly-evolving technology for patients with severe, calcific aortic stenosis. Although these procedures lessen many of the risks and complications of open surgical aortic valve replacement, there remain challenges with TAVR including electrophysiologic complications. Among TAVR prostheses, rates of conduction abnormalities (CAs) vary from less than 10% to more than 50%, with up to one-third of patients requiring placement of a permanent pacemaker following TAVR. Several predictors of CAs have been identified related to device selection, baseline conduction defects, and anatomical considerations. Current data support the hypothesis that CAs result primarily from mechanical compression of the specialized conduction system by the device, although other factors may be involved. Such abnormalities can arise immediately during the procedure or as late as several days after implantation, and can be transient or permanent. Currently, there are no clinical tools to identify patients at highest risk for CAs post-TAVR, or to predict the course of CAs in patients who experience them. Early data suggest outcomes may be worse in high-risk patients, and further studies are needed to identify these patients so as to minimize electrophysiologic complications and determine appropriate monitoring in this expanding population.

Transcatheter aortic valve implantation: 10-year anniversary part II: clinical implications

Transcatheter aortic valve implantation (TAVI) has been increasingly recognized as a curative treatment for severe aortic stenosis (AS). Despite important improvements in current device technology and implantation techniques, specific complications still remain and warrant consideration. Vascular complications and peri-procedural neurological events were the first concerns to emerge with this new technology. Recently, significant post procedural para-valvular leak has been shown to be more frequent after TAVI than after surgical aortic valve replacement (SAVR), and its potential association with worse long-term prognostic has raised concerns. In moving toward treatment of lower risk populations, structural integrity and long-term durability of heat valve prosthesis are becoming of central importance. Emerging technologies and newer generations of devices seem promising in dealing with these matters.

Computed tomography-based evaluation of aortic annulus, prosthesis size and impact on early residual aortic regurgitation after transcatheter aortic valve implantation

OBJECTIVES

Computed tomography (CT) is an increasingly utilized method for the evaluation of patient suitability for transcatheter aortic valve implantation (TAVI). The aim of this study was to analyse the role of CT in the choice of prosthesis and the prevention of residual aortic regurgitation (RAR).

METHODS

From November 2007 to September 2010, 115 patients (median age 81 years, inter-quantile range (IQR) 76-85; median ejection fraction 55%, IQR 45-60; median logistic EuroSCORE 19.7, IQR 11.0-32.1) undergoing TAVI were evaluated with a pre-procedural CT. An aortic complex was evaluated with multi-planar reconstructions, and we defined significant early RAR as RAR ≥ 2, and prosthesis/annulus mismatch (PAM) as the ratio between prosthesis size and mean annular size. All analyses were conducted for the whole sample and then separately for the two types of prosthesis implanted.

RESULTS

An Edwards-SAPIEN(®) prosthesis was implanted in 62 patients (54.7%), and a Medtronic CoreValve(®) in 52 (45.2%). Aortic annulus minimum and maximum diameters were 22.6 ± 2.1 and 26.0 ± 2.3 mm, respectively. The aortic annulus diameter and the length of the free edge of the aortic cusps were linearly related to a 1:1 ratio (P < 0.0001). Significant RAR (34 patients, 30%) appeared directly related to the annulus diameters (particularly maximum and medium diameters, P = 0.0003 and P = 0.0010, respectively) and cusp length (P = 0.0007) but inversely correlated with PAM (P = 0.0006). Prosthesis/annulus oversizing was associated with a reduction in RAR, with a cut-off of 7% as the limit below which RAR increases; moreover, we observed different cut-off values for the Edwards and CoreValve prostheses, although statistical significance was not reached for the CoreValve (respectively, 2% with P < 0.0001, 11% with P = 0.16). No association was found between PAM and possible PAM-related complications.

CONCLUSIONS

CT evaluation prior to TAVI showed that RAR was directly correlated with aortic root dimensions (particularly maximum and medium annulus diameters and cusp lengths) and inversely correlated with PAM. Oversizing the prosthesis by at least 7% reduces the risk of RAR. CT is an essential and invaluable tool in the assessment of patients undergoing TAVI.

Transcatheter Aortic Valve Implantation: Experience with the Edwards SAPIEN Device

Transcatheter aortic valve implantation (TAVI) with the Edwards SAPIEN valve has been shown to be highly beneficial to patients at high risk or with contraindications to surgical aortic valve replacement. The availability of both transfemoral and transapical approaches allows the technique to be applied in most patients. Optimal screening and technical proficiency are crucial for a successful and safe procedure. The technique poses many technical challenges in sick and fragile elderly patients. Thus, TAVI should remain confined to formally trained and proctored experienced physicians, in centers of expertise offering an optimal multidisciplinary collaboration.