Predictors of Permanent Pacemaker Implantation in Patients With Severe Aortic Stenosis Undergoing TAVR

Transcatheter Aortic Valve Replacement: Comprehensive Review and Present Status

Aortic stenosis is the most common valvular heart disease in the developed world. About 7% of the population over age 65 years suffers from degenerative aortic stenosis. The prognosis of patients with symptomatic severe aortic stenosis is dismal without valve replacement. Even though the American College of Cardiology recommends aortic valve replacement to treat this condition as a class I recommendation, approximately one third of these patients over the age of 75 years are not referred for surgery. Typically, this is from concern about prohibitive surgical risk associated with patient frailty, comorbidities, age, and severe left ventricular dysfunction. The advent in France of transcatheter aortic valve replacement has raised the hope in the United States for an alternative, less invasive treatment for aortic stenosis. Two recent trials-the Placement of AoRTic TraNscathetER Valve Trial Edwards SAPIEN Transcatheter Heart Valve (Partner) and the CoreValve US Pivotal-have established transcatheter aortic valve replacement as the preferred approach in patients who are at high or prohibitive surgical risk. The more recently published Partner 2 trial has shown the feasibility of transcatheter aortic valve replacement in intermediate-surgical-risk patients as well. With a profile that promises easier use and better valve performance and delivery, newer-generation valves have shown their potential for further improvement in safety profile and overall outcomes. We review the history and status of this topic.

Pathophysiology, incidence and predictors of conduction disturbances during Transcatheter Aortic Valve Implantation

INTRODUCTION

Over the past decade, transcatheter aortic valve implantation (TAVI) has evolved rapidly toward an extremely reproducible, safe and effective procedure, with a marked reduction of its related complications. However, the occurrence of conduction disturbances and the need for permanent pacemaker implantation (PPI) after TAVI remains a concern. Areas covered: In this article review, we will go through the mechanisms involved in conduction disturbances after TAVI, and we will discuss the key aspects of pathophysiology, incidence and predictors of conduction disturbances following Transcatheter Aortic Valve Implantation. The evaluation of patient's valve anatomy and the selection of the most appropriate prosthesis have been proposed as a valuable options to reduce the incidence of conductions disturbances. Moreover, in recent times, a great number of new TAVI devices, so-called 'second-generation devices', have been introduced to address the limitations of the first-generation devices, including conduction disturbance, with scarce results. Expert commentary: Conduction disturbances after TAVI are increasingly recognized as an important issue in TAVI complications. Further characterization of the procedural- and patient-related factors that contribute to the development of conduction abnormalities will help to improve prosthesis designs and patient selection, making TAVI even more safer.

Transcatheter aortic valve implantation: new hope in the management of valvular heart disease

Severe calcific aortic stenosis is relatively common, and unless treated with valve replacement it carries an adverse prognosis. A large number of patients, however, are denied surgery due to their advanced age or coexistent medical conditions that increase perioperative cardiovascular risks. Transcatheter aortic valve implantation (TAVI), a technique in which a bioprosthetic valve is inserted via a catheter and implanted within the diseased native aortic valve, is a new therapeutic modality for treatment of older patients with severe symptomatic aortic stenosis and other comorbidities, who have an inherently high surgical risk. This review will provide an overview of the pivotal trials in the development of TAVI; while also investigating important complications and limitations of the procedure and evaluating how new valves are being designed and clinically evaluated, with the ultimate goal of reducing potential complications and expanding the use of TAVI to lower-risk patient cohorts.

The safety of introducing a new generation TAVR device: one departments experience from introducing a second generation repositionable TAVR

Background

In the evolving field of transcatheter aortic valve replacements a new generation of valves have been introduced to clinical practice. With the complexity of the TAVR procedure and the unique aspects of each TAVR device, there is a perceived risk that changing or adding a new valve in a department could lead to a worse outcome for patients, especially during the learning phase. The objective was to study the safety aspect of introducing a second generation repositionable transcatheter valve (Boston Scientific Lotus valve besides Edwards Sapien valve) in a department.

Methods

In a retrospective study, 53 patients receiving the Lotus system, and 47 patients receiving the Sapien system over a period of three years were compared for short-term outcome according to VARC-2 definitions and 1-year survival.

Results

Outcome in terms VARC-2 criteria for early safety and clinical efficacy, stroke rate, and survival at 30 days and at 1 year were similar. The Lotus valve had less paravalvular leakage, where 90% had none or trace aortic insufficiency as compared to only 48% for the Sapien system.

Conclusions

Introduction of a new generation valve can be done with early device success and safety, and without jeopardizing the outcome for patients up to one year. We found no adverse effects by changing valve type and observed improved outcome in terms of lower PVL-rates. Both existing and new centers starting a TAVR program can benefit from the use of a new generation device.

In Vitro Hydrodynamic Assessment of a New Transcatheter Heart Valve Concept (the TRISKELE)

This study presents the in vitro hydrodynamic assessment of the TRISKELE, a new system suitable for transcatheter aortic valve implantation (TAVI), aiming to mitigate the procedural challenges experienced with current technologies. The TRISKELE valve comprises three polymeric leaflet and an adaptive sealing cuff, supported by a novel fully retrievable self-expanding nitinol wire frame. Valve prototypes were manufactured in three sizes of 23, 26, and 29 mm by automated dip-coating of a biostable polymer, and tested in a hydrodynamic bench setup in mock aortic roots of 21, 23, 25, and 27 mm annulus, and compared to two reference valves suitable for equivalent implantation ranges: Edwards SAPIEN XT and Medtronic CoreValve. The TRISKELE valves demonstrated a global hydrodynamic performance comparable or superior to the controls with significant reduction in paravalvular leakage. The TRISKELE valve exhibits enhanced anchoring and improved sealing. The valve is currently under preclinical investigation.

Rationale and design of the Edwards SAPIEN-3 periprosthetic leakage evaluation versus Medtronic CoreValve in transfemoral aortic valve implantation (ELECT) trial : A randomised comparison of balloon-expandable versus self-expanding transcatheter aortic valve prostheses

Background and objectives

Periprosthetic aortic regurgitation (PPR) after transcatheter aortic valve implantation (TAVI) remains an important issue associated with impaired long-term outcomes. The current randomised study aims to evaluate potential differences between the balloon-expandable Edwards SAPIEN-3 and the self-expanding Medtronic CoreValve system with the main focus on post-TAVI PPR by means of novel imaging endpoints, and an additional focus on other clinical endpoints.

Endpoints

The primary endpoint of this study is quantitative assessment of the severity of post-procedural PPR using cardiac magnetic resonance imaging. Several other novel imaging modalities (X-ray contrast angiography, echocardiography) are used as secondary imaging modalities for the assessment of PPR following TAVI. Secondary objectives of the study include clinical outcomes such as cerebral and kidney injury related to TAVI, and quality of life.

Methods and design

The ELECT study is a single-centre, prospective, two-armed randomised controlled trial. For the purpose of this study, 108 consecutive adult patients suitable for transfemoral TAVI will be randomly allocated to receive the SAPIEN-3 (n = 54) or the CoreValve system (n = 54).

Discussion

The ELECT trial is the first randomised controlled trial to quantitatively compare the extent of post-TAVI PPR between the SAPIEN-3 and CoreValve. Furthermore, it will evaluate potential differences between the two prostheses with regard to mid-term clinical outcome and quality of life.

Transcatheter Aortic Valve Replacement: State of the Art and Future Directions

Transcatheter aortic valve replacement (TAVR) is a transformational and rapidly evolving treatment for patients with aortic stenosis who require valve replacement. Novel technological advancements have made this percutaneous minimally invasive therapy a first-line treatment for many patients at extreme risk for conventional cardiac surgery. New devices and improvements in existing devices have reduced procedural complications, and scientific trials are investigating the role of TAVR in lower-risk aortic stenosis populations, in patients with aortic regurgitation, and in patients with bicuspid aortic valve disease. Finally, there is intense interest in identifying patients in whom the risk-benefit ratio of TAVR is not favorable and should not be performed.

[Cardiac permanent pacemaker after transcatheter aortic valve implantation: A predictive and scientific review]

Transcatheter aortic valve implantation (TAVI) is nowadays a worldwide technique in the field of treating aortic stenosis. One of the main side effects linked to the technique are mostly attached to rhythm disturbances, such as atrioventricular (AV) and intraventricular blocks. Consequently, a pacemaker implantation is often required. That implantation rate is estimated between 8 and 30%, depending on the valve chosen. Thanks to main meta analysis on the subject, it has been managed to isolate the following risks factors for AV block development: preoperative right bundle branch block (RBBB: the most powerful element), complete AV block during the procedure, male gender, a so-called porcelain aorta, the absence of previous valvular surgery, the aortic annulus size (i.e when that size is inferior to the valve's one) and the QRS duration after the procedure (the superior threshold has been set at 128ms for the Corevalve). The currently recommendations advice to implant a pacemaker are as followed: high grade AV block (in the main studies, the implantation occurs within the 5 days after the TAVI), complete and transient AV block during the TAVI, second degree AV block and RBBB associated with first degree AV block. Our article aims to review the arrhythmic issues of TAVI.

Outcomes After Transcatheter Aortic Valve Replacement Using a Novel Balloon-Expandable Transcatheter Heart Valve: A Single-Center Experience

OBJECTIVES

Evaluation of 30-day outcomes after transcatheter aortic valve replacement (TAVR) with the novel balloon-expandable SAPIEN 3 (S3) transcatheter heart valve (THV) (Edwards Lifesciences, Irvine, California) emphasizing the updated Valve Academic Research Consortium (VARC-2) criteria.

BACKGROUND

Preliminary data on clinical performance with the S3 THV are promising. However, information regarding 30-day outcome is limited.

METHODS

A total of 250 consecutive patients undergoing transfemoral TAVR with the S3 THV at our center were enrolled, and outcomes according to VARC-2 criteria were analyzed at 30 days.

RESULTS

The mean age was 81.0 ± 6.2 years, median logistic EuroSCORE (European System for Cardiac Operative Risk Evaluation) and Society of Thoracic Surgeons score were 12.1% and 4.4%, respectively. VARC-2-defined device success was achieved in 244 patients (97.6%); moderate paravalvular leakage developed in 5 patients (2.0%). One patient (0.4%) died of a noncardiac cause and 8 patients (3.2%) had a stroke. Life-threatening bleeding and major vascular complications occurred in 12 (4.8%) and 9 (3.6%) of the patients, respectively. From discharge to 30 days, 5 patients (2.0%) were hospitalized due to valve-related symptoms or worsening of heart failure. The VARC-2 composite early safety endpoint was observed in 25 patients (10.0%). Permanent pacemaker implantation rate at 30 days was 15.2%. Myocardial infarction, coronary obstruction requiring intervention, valve-related dysfunction, and endocarditis were not observed.

CONCLUSIONS

We found very good 30-day results using the novel S3 THV with a low rate of clinical events according to VARC-2 criteria. The S3 THV is associated with high procedural success and favorable early safety profile. The need for pacemaker implantations appears to be more frequent than with its predecessor.

Permanent His-bundle pacing in patients with prosthetic cardiac valves

BACKGROUND

Conduction disease is not uncommon after prosthetic valve (PV) surgery. The feasibility of His-bundle pacing (HBP) in this patient population is not well studied.

OBJECTIVE

The purpose of this study was to report our experience with permanent HBP in patients undergoing pacemaker implantation after PV surgery.

METHODS

Permanent HBP was attempted in patients with AV conduction disease after PV surgery referred for pacemaker implantation. Conduction disease was characterized as AV nodal vs infranodal. Feasibility, relationship of HBP lead to PVs, and HBP characteristics were recorded.

RESULTS

Thirty patients (47% men, age 74 ± 12 years, left ventricular ejection fraction 49% ± 11%) with AV conduction disease (100% patients; 14 with infranodal block; right bundle branch block 9, left bundle branch block 5, intraventricular conduction delay 1) underwent HBP. PVs included aortic valve replacement (AVR) in 8 patients (infranodal block 6 patients), tricuspid valve (TV) ring with mitral valve replacement or repair (MVR) in 10 patients (AV nodal block 9 patients), transcatheter aortic valve replacement (TAVR) in 4 patients (infranodal block 4 patients), and MVR alone in 6 patients. HBP was successful in 28 patients (93%) (selective HBP 50%). His bundle (HB) recruitment was unsuccessful in 2 patients with TAVR. AVR/TAVR and TV ring served as anatomic landmarks for localizing the HB. Successful sites of HBP were posterior and inferior to AVR/TAVR and distal and septal to the TV ring. Baseline QRSd improved from 124 ± 32 ms to 118 ± 20 ms (P = .39). HBP threshold at implant was 1.45 ± 1 V at 1 ms.

CONCLUSION

Permanent HBP was feasible in 93% of patients with PVs. Patients with AVR/TAVR predominantly developed infranodal block compared to AV nodal block in patients with TV ring/MVR. Location of PV might serve as a landmark for identifying the site of the HB.

Unravelling the (arte)fact of increased pacemaker rate with the Edwards SAPIEN 3 valve

AIMS

Early data on the Edwards SAPIEN 3 valve (S3-THV) have shown low rates of paravalvular leaks and vascular complications but relatively high 30-day permanent pacemaker implantation (PPMI) rates. No direct comparisons on clinical outcomes including PPMI rates are available for the S3-THV and the Edwards SAPIEN XT (XT-THV). We aimed to compare the 30-day PPMI rates in patients treated with the two prostheses and to assess the interplay among valve type, depth of implantation and PPMI rate.

METHODS AND RESULTS

Two hundred and nine patients treated by TAVI were considered. The S3-THV was associated with higher PPMI rates compared to the XT-THV, both overall and in subgroups matched for several predictors of PPMI. However, in the S3-THV group, 30-day PPMI was strictly associated with deep valve implantation, and PPMI risk of high-implanted S3-THVs was similar to that of the overall XT-THV matched group. No cases of significant paravalvular leak were observed in the S3-THV group.

CONCLUSIONS

The S3-THV was associated with a higher incidence of PPMI compared to the XT-THV. In the S3-THV group, pacemaker implantation was strictly associated with deep valve implantation. An implantation technique involving higher initial placement of the central marker (from 0 to 3 mm above the base of the aortic cusps) and, as a consequence, higher final valve depth might help in preventing post-TAVI PPMI with the S3-THV, without affecting the risk of paravalvular leak.

The Prognostic Impact of New-Onset Persistent Left Bundle Branch Block Following Transcatheter Aortic Valve Implantation: A Meta-analysis

New-onset persistent left bundle branch block (NOP-LBBB) is one of the most common conduction disturbances after transcatheter aortic valve implantation (TAVI). We hypothesized that NOP-LBBB may have a clinically negative impact after TAVI. To find out, we conducted a systematic literature search of the MEDLINE/PubMed and Embase databases. Observational studies that reported clinical outcomes of NOP-LBBB patients after TAVI were included. The random-effects model was used to combine odds ratios, risk ratios, or hazard ratios (HRs) with 95% confidence intervals. Adjusted HRs were utilized over unadjusted HRs or risk ratios when available. A total of 4049 patients (807 and 3242 patients with and without NOP-LBBB, respectively) were included. Perioperative (in-hospital or 30-day) and midterm all-cause mortality and midterm cardiovascular mortality were comparable between the groups. The NOP-LBBB patients experienced a higher rate of permanent pacemaker implantation (HR: 2.09, 95% confidence interval: 1.12-3.90, P = 0.021, I(2) = 83%) during midterm follow-up. We found that NOP-LBBB after TAVI resulted in higher permanent pacemaker implantation but did not negatively affect the midterm prognosis. Therefore, careful observation during the follow-up is required.

Comparison of Edwards Sapien XT versus Lotus Valve Devices in Terms of Electrophysiological Study Parameters in Patients Undergoing TAVI

BACKGROUND

The purpose of this study is to assess the electrocardiographic and electrophysiological parameters of conduction abnormalities in patients undergoing transcatheter aortic valve implantation (TAVI) due to severe aortic valve stenosis.

METHODS

The study included 55 patients who underwent TAVI using either the Boston Scientific Lotus (n:25) (Boston Scientific, Natick, MA, USA) or Edwards Sapien XT (n:30) (Edwards Lifesciences, Irvine, CA, USA) prostheses. An electrophysiological study (EPS) was performed in the catheterization room immediately before the initial balloon valvuloplasty and immediately after prosthesis implantation.

RESULTS

QRS duration and His-bundle to His-ventricle (HV) intervals, which were similar between the two groups before the procedure, were found to be significantly higher in the Lotus valve group postprocedure. Permanent pacemakers (PPMs) were required more frequently in the Lotus group than in the Sapien XT group at discharge (24.0% vs 6.7%, P = 0.07). With the exception of a higher prevalence of paravalvular leakage (P < 0.001) in patients undergoing Sapien XT implantation, other clinical outcomes were similar between the two groups. Multiple regression analysis revealed that baseline atrioventricular (AV) conduction disorders and HV intervals after the procedure were independently associated with PPM implantation after TAVI.

CONCLUSION

In this first study comparing the findings of EPS and electrocardiography, the impact of the Lotus valve on AV conduction systems was greater than that of the Sapien XT. However, the need for PPM was higher in the Lotus valve than in the Sapien XT. PPM requirement is related to valve design; it may decrease with reduced frame height and metal burden in novel valve systems.

Feasibility and Safety of Transcatheter Aortic Valve Implantation Performed Without Intensive Care Unit Admission

Admission to the intensive care unit (ICU) is a standard of care after transcatheter aortic valve implantation (TAVI); however, the improvement of the procedure and the need to minimize the unnecessary use of medical resources call into question this strategy. We evaluated prospectively 177 consecutive patients who underwent TAVI. Low-risk patients, admitted to conventional cardiology units, had stable clinical state, transfemoral access, no right bundle branch block, permanent pacing with a self-expandable valve, and no complication occurring during the procedure. High-risk patients included all the others transferred to ICU. In-hospital events were the primary end point (Valve Academic Research Consortium 2 criteria). The mean age of patients was 83.5 ± 6.5 years, and the mean logistic EuroSCORE was 14.6 ± 9.7%. The balloon-expandable SAPIEN 3 valve was mainly used (n = 148; 83.6%), mostly with transfemoral access (n = 167; 94.4%). Among the 61 patients (34.5%) included in the low-risk group, only 1 (1.6%) had a minor complication (negative predictive value 98.4%, 95% confidence interval [CI] 0.91 to 0.99). Conversely, 31 patients (26.7%) from the high-risk group had clinical events (positive predictive value 26.7%, 95% CI 0.19 to 0.35), mainly conductive disorders requiring pacemaker (n = 26; 14.7%). In multivariate analysis, right bundle branch block (odds ratio [OR] 14.1, 95% CI 3.5 to 56.3), use of the self-expandable valve without a pacemaker (OR 5.5, 95% CI 2 to 16.3), vitamin K antagonist treatment (OR 3.8, 95% CI 1.1 to 12.6), and female gender (OR 2.6, 95% CI 1.003 to 6.9) were preprocedural predictive factors of adverse events. In conclusion, our results suggested that TAVI can be performed safely without ICU admission in selected patients. This strategy may optimize efficiency and cost-effectiveness of procedures.

Optimized Implantation Height of the Edwards SAPIEN 3 Valve to Minimize Pacemaker Implantation After TAVI

AIM

The transcatheter aortic valve SAPIEN 3 aims at reducing paravalvular leakage (PVL). The new design with outer sealing cuff may increase the risk of permanent pacemaker implantation (PPM). The aim of our study was to evaluate the optimal implantation height of the SAPIEN 3.

METHODS AND RESULTS

We analysed the correlation between the implantation height of the valve and the need for PPM in 131 patients. The PPM rate for the entire group after TAVI was 18% (n = 24). In patients with a marker distance <2 mm ("low implantation"), the PPM rate was 32%, whereas in patients with a distance ≥2 mm ("high implantation"), the rate was only 4.7% (OR of 0.1 (0.03-0.37, P < 0.001)).

CONCLUSION

The risk of periprocedural PPM with the Edwards SAPIEN 3 depends on implantation height; it is increased when using conventional implantation techniques. This risk can be minimized below 5% PPM by choosing a higher implantation technique with the central marker 2 mm or more over the annulus plane.

[Transcatheter aortic valve implantation (TAVI): Current perspectives]

Transcatheter aortic valve implantation (TAVI) has evolved as the treatment modality of choice for elderly patients with symptomatic severe aortic stenosis who are at high risk for surgery. More than 10,000 TAVI procedures were undertaken in Germany during 2014.A mortality benefit has been shown for TAVI compared with conservative treatment in patients deemed inoperable, and the procedure was proven to be at least non-inferior to surgical aortic valve replacement in high-risk patients. Through improvements in preprocedural imaging and in valve technology as well as increasing operator and surgical team experience, TAVI has developed rapidly in the past few years. Complication rates declinded considerably and the latest study results even suggest a superiority of TAVI to surgical valve replacement in patients at intermediate operative risk. Nevertheless, the challenge to avoid procedure-specific complications influencing the outcome still remains. Therefore, making an individual decision about the approach and the valve prosthesis in an interdisciplinary heart team consisting of a cardiologist and a cardiac surgeon is indispensable for guaranteeing the best therapy for the patient.Considering the rapid developments and procedural improvements in this field, randomized trials are required to assess whether the indication for TAVI may be extended to patients at lower perioperative risk in the future.

Transcatheter or Surgical Aortic-Valve Replacement in Intermediate-Risk Patients

BACKGROUND

Previous trials have shown that among high-risk patients with aortic stenosis, survival rates are similar with transcatheter aortic-valve replacement (TAVR) and surgical aortic-valve replacement. We evaluated the two procedures in a randomized trial involving intermediate-risk patients.

METHODS

We randomly assigned 2032 intermediate-risk patients with severe aortic stenosis, at 57 centers, to undergo either TAVR or surgical replacement. The primary end point was death from any cause or disabling stroke at 2 years. The primary hypothesis was that TAVR would not be inferior to surgical replacement. Before randomization, patients were entered into one of two cohorts on the basis of clinical and imaging findings; 76.3% of the patients were included in the transfemoral-access cohort and 23.7% in the transthoracic-access cohort.

RESULTS

The rate of death from any cause or disabling stroke was similar in the TAVR group and the surgery group (P=0.001 for noninferiority). At 2 years, the Kaplan-Meier event rates were 19.3% in the TAVR group and 21.1% in the surgery group (hazard ratio in the TAVR group, 0.89; 95% confidence interval [CI], 0.73 to 1.09; P=0.25). In the transfemoral-access cohort, TAVR resulted in a lower rate of death or disabling stroke than surgery (hazard ratio, 0.79; 95% CI, 0.62 to 1.00; P=0.05), whereas in the transthoracic-access cohort, outcomes were similar in the two groups. TAVR resulted in larger aortic-valve areas than did surgery and also resulted in lower rates of acute kidney injury, severe bleeding, and new-onset atrial fibrillation; surgery resulted in fewer major vascular complications and less paravalvular aortic regurgitation.

CONCLUSIONS

In intermediate-risk patients, TAVR was similar to surgical aortic-valve replacement with respect to the primary end point of death or disabling stroke. (Funded by Edwards Lifesciences; PARTNER 2 ClinicalTrials.gov number, NCT01314313.).

Antiplatelet regimens in the long-term secondary prevention of transient ischaemic attack and ischaemic stroke: an updated network meta-analysis

OBJECTIVE

To examine the comparative efficacy and safety of different antiplatelet regimens in patients with prior non-cardioembolic ischaemic stroke or transient ischaemic attack.

DESIGN

Systematic review and network meta-analysis.

DATA SOURCES

As on 31 March 2015, all randomised controlled trials that investigated the effects of antiplatelet agents in the long-term (≥ 3 months) secondary prevention of non-cardioembolic transient ischaemic attack or ischaemic stroke were searched and identified.

OUTCOME MEASURES

The primary outcome measure of efficacy was serious vascular events (non-fatal stroke, non-fatal myocardial infarction and vascular death). The outcome measure of safety was any bleeding.

RESULTS

A total of 36 randomised controlled trials (82,144 patients) were included. Network meta-analysis showed that cilostazol was significantly more effective than clopidogrel (OR 0.77, 95% credible interval 0.60-0.98) and low-dose (75-162 mg daily) aspirin (0.69, 0.55-0.86) in the prevention of serious vascular events. Aspirin (50 mg daily) plus dipyridamole (400 mg daily) and clopidogrel reduced the risk of serious vascular events compared with low-dose aspirin; however, the difference was not statistically significant. Furthermore, low-dose aspirin was as effective as higher daily doses. Cilostazol was associated with a significantly lower bleeding risk than most of the other regimens. Moreover, aspirin plus clopidogrel was associated with significantly more haemorrhagic events than other regimens. Direct comparisons showed similar results as the network meta-analysis.

CONCLUSIONS

Cilostazol was significantly more effective than aspirin and clopidogrel alone in the long-term prevention of serious vascular events in patients with prior non-cardioembolic ischaemic stroke or transient ischaemic attack. Cilostazol was associated with a significantly lower bleeding risk than low-dose aspirin (75-162 mg daily) and aspirin (50 mg daily) plus dipyridamole (400 mg daily). Low-dose aspirin was as effective as higher daily doses. However, further large, randomised, controlled, head-to-head trials are needed, especially in non-Asian ethnic groups.

Transcatheter aortic valve implantation with the new balloon-expandable Sapien 3 versus Sapien XT valve system: a propensity score-matched single-center comparison

BACKGROUND

The new balloon-expandable Sapien 3 transcatheter heart valve (S3-THV) incorporates new features to reduce aortic regurgitation (AR) and vascular complications in transcatheter aortic valve implantation. Aim of this study is to compare the outcomes of the S3-THV with the preceding Sapien XT THV (SXT-THV) in patients who underwent transcatheter aortic valve implantation for symptomatic severe native aortic stenosis.

METHODS AND RESULTS

Eligible patients were retrospectively identified in our institutional database and periprocedural clinical and imaging data were collected. Non-parsimonious one-to-many propensity score matching was performed to account for differences in baseline characteristics. Between November 2011 and December 2014, 167 patients underwent balloon-expandable transcatheter aortic valve implantation with either the S3-THV (n=49) or SXT-THV (n=118). Forty-four (89.8%) S3-THV patients were matched to 66 (55.9%) SXT-THV patients (mean age 80.3±8.4 and 80.5±7.8 years, median EuroSCORE 15.8 and 16.5%, respectively). In the S3-THV and SXT-THV groups, transfemoral approach (77.3% versus 78.8%) and postdilatation rates (15.9% versus 12.1%) were similar. Predischarge echocardiography demonstrated a lower incidence of ≥mild AR (15.9% versus 46.2%, P=0.003) for the S3-THV, despite reduced annulus area to prosthesis oversizing (8.2±5.1 versus 18.2±10.7%, P=0.001). Transfemoral access site-related life-threatening or major bleedings and vascular complications were absent in the S3-THV group (0% versus 7.7%, P=0.15). No differences were observed in pacemaker implantation rate (9.8% versus 8.8%, P=0.94) and 30-day mortality (both 5%).

CONCLUSIONS

In this retrospective, propensity score-matched analysis, the S3-THV performed superiorly to the SXT-THV, as demonstrated by improved valve patency and increased transfemoral access safety.

Clinical utility of multi-detector cardiac computed tomography in structural heart interventions

In recent years, there have been major advances in structural interventional cardiology, which have revolutionized the practice of cardiology. Appropriate selection and follow-up of patients undergoing these structural heart interventions is vital. Multi-detector computed tomography (MDCT) has emerged as a key imaging modality in the peri-procedural assessment of patients undergoing multiple structural cardiac interventions. The purpose of this review is to provide an evidence-based clinical update on the roles of MDCT in both established and evolving structural heart interventions, including transcatheter aortic valve replacement (TAVR) and transcatheter mitral valve implantation (TMVI). The utility of MDCT in the peri-procedural assessment of patients undergoing pulmonary vein isolation (PVI) for atrial fibrillation, cardiac resynchronization therapy (CRT) and left atrial appendage (LAA) closure will also be reviewed.

Mechanisms of Heart Block after Transcatheter Aortic Valve Replacement - Cardiac Anatomy, Clinical Predictors and Mechanical Factors that Contribute to Permanent Pacemaker Implantation

Transcatheter aortic valve replacement (TAVR) has emerged as a valuable, minimally invasive treatment option in patients with symptomatic severe aortic stenosis at prohibitive or increased risk for conventional surgical replacement. Consequently, patients undergoing TAVR are prone to peri-procedural complications including cardiac conduction disturbances, which is the focus of this review. Atrioventricular conduction disturbances and arrhythmias before, during or after TAVR remain a matter of concern for this high-risk group of patients, as they have important consequences on hospital duration, short- and long-term medical management and finally on decisions of device-based treatment strategies (pacemaker or defibrillator implantation). We discuss the mechanisms of atrioventricular disturbances and characterise predisposing factors. Using validated clinical predictors, we discuss strategies to minimise the likelihood of creating permanent high-grade heart block, and identify factors to expedite the decision to implant a permanent pacemaker when the latter is unavoidable. We also discuss optimal pacing strategies to mitigate the possibility of pacing-induced cardiomyopathy.

An up-to-date overview of the most recent transcatheter implantable aortic valve prostheses

Over the past decade transcatheter aortic valve implantation (TAVI) has evolved towards the routine therapy for high-risk patients with severe aortic valve stenosis. Technical refinements in TAVI are rapidly evolving with a simultaneous expansion of the number of available devices. This review will present an overview of the current status of development of TAVI-prostheses; describes the technical features and applicability of each device and the clinical data available.