Current knowledge for the risk factors of early permanent pacemaker implantation following transcatheter aortic valve replacement and what is next for the primary prevention?

In this editorial,we comprehensively summarized the preoperative risk factors of early permanent pacemaker implantation after transcatheter aortic valve replacement(TAVR)among patients with severe aortic stenosis from several renowned clinical studies and focused on the primary prevention of managing the modifiable factors,e.g.,paroxysmal atrial fibrillation before the TAVR.

Prediction of permanent pacemaker implantation after transcatheter aortic valve replacement:The role of machine learning

BACKGROUND Atrioventricular block requiring permanent pacemaker(PPM)implantation is an important complication of transcatheter aortic valve replacement(TAVR).Application of machine learning could potentially be used to predict preprocedural risk for PPM.AIM To apply machine learning to be used to predict pre-procedural risk for PPM.METHODS A retrospective study of 1200 patients who underwent TAVR(January 2014-December 2017)was performed.964 patients without prior PPM were included for a 30-d analysis and 657 patients without PPM requirement through 30 d were included for a 1-year analysis.After the exclusion of variables with near-zero variance or≥50%missing data,167 variables were included in the random forest gradient boosting algorithm(GBM)optimized using 5-fold cross-validations repeated 10 times.The receiver operator curve(ROC)for the GBM model and PPM risk score models were calculated to predict the risk of PPM at 30 d and 1 year.RESULTS Of 964 patients included in the 30-d analysis without prior PPM,19.6%required PPM post-TAVR.The mean age of patients was 80.9±8.7 years.42.1%were female.Of 657 patients included in the 1-year analysis,the mean age of the patients was 80.7±8.2.Of those,42.6%of patients were female and 26.7%required PPM at 1-year post-TAVR.The area under ROC to predict 30-d and 1-year risk of PPM for the GBM model(0.66 and 0.72)was superior to that of the PPM risk score(0.55 and 0.54)with a P value<0.001.CONCLUSION The GBM model has good discrimination and calibration in identifying patients at high risk of PPM post-TAVR.

Transcatheter aortic valve replacement in low-risk young population:A double edge sword?

Since the advent of transcatheter aortic valve replacement(TAVR)in 2002,it has now become the default interventional strategy for symptomatic patients presenting with severe aortic stenosis,particularly in intermediate to highsurgical risk patients.In 2019,the United States Food and Drug Administration approved TAVR in low-risk patients based on two randomized trials.However,these breakthrough trials excluded patients with certain unfavorable anatomies and odd profiles.While currently there is no randomized study of TAVR in young patients,it may be preferred by the young population given the benefits of early discharge,shorter hospital stay,and expedite recovery.Nonetheless,it is important to ruminate various factors including lifetime expectancy,risk of pacemaker implantation,and the need for future valve or coronary interventions in young cohorts before considering TAVR in these patients.Furthermore,the data on long-term durability(>10 years)of TAVR is still unknown given most of the procedures were initially performed in the high or prohibitive surgical risk population.Thus,this editorial aims to highlight the importance of considering an individualized approach in young patients with consideration of various factors including lifetime expectancy while choosing TAVR against surgical aortic valve replacement.

Pacemaker post transcatheter aortic valve replacement:A multifactorial risk?

Pacemaker post-transcatheter aortic valve replacement is related to multifactorial risk.Nwaedozie et al brought to the body of evidence electrocardiogram and clinical findings.However,procedural characteristics have at least as much impact on the final need for a permanent pacemaker and potentially on the pacing rate.In this regard,long-term follow-up and understanding of the impact of long-term stimulation is of utmost importance.

Value of a comprehensive geriatric assessment for predicting one-year outcomes in patients undergoing transcatheter aortic valve implantation: results from the CGA-TAVI multicentre registry

Background In a three-month report from the CGA-TAVI registry, we found the Multidimensional Prognostic Index (MPI) and Short Physical Performance Battery (SPPB) to be of value for predicting short-term outcomes in elderly patients undergoing transcatheter aortic valve implantation (TAVI). In the present analysis, we examined the association of these tools with outcomes up to one year post-TAVI. Methods CGA-TAVI is an international, observational registry of geriatric patients undergoing TAVI. Patients were assessed using the MPI and SPPB. Efficacy of baseline values and any postoperative change for predicting outcome were established using logistic regression. Kaplan- Meier analysis was carried out for each comprehensive geriatric assessment tool, with survival stratified by risk category. Results One year after TAVI, 14.1% of patients deceased, while 17.4% met the combined endpoint of death and/or non-fatal stroke, and 37.7% the combined endpoint of death and/or hospitalisation and/or non-fatal stroke. A high-risk MPI score was associated with an increased risk of all-cause mortality (aOR = 36.13, 95% CI: 2.77–470.78, P = 0.006) and death and/or non-fatal stroke (aOR = 10.10, 95% CI: 1.48–68.75, P = 0.018). No significant associations were found between a high-risk SPPB score and mortality or two main combined endpoints. In contrast to a worsening SPPB, an aggravating MPI score at three months post-TAVI was associated with an increased risk of death and/or non-fatal stoke at one year (aOR = 95.16, 95% CI: 3.41–2657.01). Conclusions The MPI showed value for predicting the likelihood of death and a combination of death and/or non-fatal stroke by one year after TAVI in elderly patients.

Transcatheter aortic valve implantation:Current status and future perspectives

Although surgical aortic valve replacement is the standard therapy for severe aortic stenosis(AS),about one third of patients are considered inoperable due to unacceptable surgical risk.Under medical treatment alone these patients have a very poor prognosis with a mortality rate of 50%at 2 years.Transcatheter aortic valve implantation(TAVI)has been used in these patients,and has shown robust results in the only randomized clinical trial of severe AS treatment performed so far.In this review,we will focus on the two commercially available systems:Edwards SAPIEN valve and CoreValve Revalving system.Both systems have demonstrated success rates of over 90%with 30-d mortality rates below 10%in the most recent transfemoral TAVI studies.Moreover,long-term studies have shown that the valves have good haemodynamic performance.Some studies are currently exploring the non-inferiority of TAVI procedures vs conventional surgery in high-risk patients,and long-term clinical results of the percutaneous valves.In this article we review the current status of TAVI including selection of patients,a comparison of available prostheses,results and complications of the procedure,clinical outcomes,and future perspectives.

Cardiac rehabilitation and mid-term follow-up after transcatheter aortic valve implantation

Background Evaluation of patient outcomes following transcatheter aortic valve implantation （TAVI） has usually been based on survival and clinical improvement. Studies on quality of life are limited, and data from comprehensive assessments after the procedure are lacking. Methods Sixty patients referred for cardiac rehabilitation after TAVI underwent in-hospital and after-discharge multidimensional assessments to evaluate clinical, functional, and nutritional statuses, degree of autonomy, cognitive impairment, depression and quality of life. Results On admission to rehabilitation, approximately half of the patients had severe functional impairment and dependence for basic activities of daily living. During their hospital stay, one-third of the patients suffered significant clinical complications and two had to be transferred to the implantation center. Despite this, the overall outcome was very good. All of the remaining patients were clinically stable at discharge and functional status, autonomy and quality of life were improved in most. During a mean follow-up of 540 days （range： 192-738 days）, five patients died from noncardiac causes, three were hospitalized for cardiac events, and nine for non cardiac reasons. Functional status and autonomy remained satisfactory in the majority of patients and most continued to live independently. Conclusions Patients referred for rehabilitation after TAVI are often very frail, with a high grade of functional impairment, dependence on others and high risk of clinical complications. During a rehabilitation programme, based on a multidimensional assessment and intervention, most patients showed significant improvement in functional status, quality of life, and autonomy, which remained stable in the majority of subjects during mid-term follow-up.

Evaluation of CA125 and NT-proBNP values in patients undergoing transcatheter aortic valve implantation

Background Transcatheter aortic valve implantation （TAVI） is a minimally invasive, emerging therapy in surgically high risk, or in- operable patients. Parameters used for risk classification have some deficiencies in the selection of patients. The objective of this study is to evaluate the impact of TAVI on carbohydrate antigen 125 （CA125） and N-terminal pro brain-type natriuretic peptide （NT-proBNP） as biomarkers that have been used frequently in recent years, and also the relationship of these biomarkers to prognosis. Methods ＆ Results Transcatheter aortic valve implantation was practiced on 31 patients in this study. Then, CA125 and NT-proBNP levels studied in patients prior to and after the TAVI were evaluated. The patients were also grouped in accordance with their left ventrieular ejection fraction （LVEF） and CA125 levels （LVEF 〉 40% and 〈 40%; CA125 ≤ 35 U/L and 〉 35 U/L）. The TAVI operation was successfully performed in all patients. There was no in-hospital mortality and substantial improvement in functional capacity was detected at follow ups. In addition, a statistically significant decrease was detected in post-TAVI CA 125 and NT-proBNP levels of all patients （CA 125 83.8 ± 18.1 U/L vs. 64.3 ±14.2 U/L, P = 0.008; NT-proBNP： 4633.6± 627.6 pg/mL vs. 2866.3±536.8 pg/mL, P 〈 0.001）. In groups divided according to the CA125 levels, there was also statistically significant post-TAVI decline in CA125 levels. Within CA125 〉 35 U/L and LVEF 〈 40% groups, the permanent need for a pacemaker was required in one （3.2%） patient and mortality was observed in two （6.4%） patients after TAVI at follow up. Conclusions The results show that TAVI can be performed effectively and reliably in patients with high baseline levels of CA125 and NT-proBNP. These biomarkers are reduced substantially with TAVI, while high biomarker levels are associated with undesired events, and certainly, these biomarkers can be used for risk classifications in patient selection for TAVI.

Fluid-Structure Interaction in Problems of Patient Specific Transcatheter Aortic Valve Implantation with and Without Paravalvular Leakage Complication

Paravalvular Leakage(PVL)has been recognized as one of the most dangerous complications in relation to Transcathether Aortic Valve Implantation(TAVI)activities.However,data available in the literature about Fluid Structure Interaction(FSI)for this specific problem are relatively limited.In the present study,the fluid and structure responses of the hemodynamics along the patient aorta model and the aortic wall deformation are studied with the aid of numerical simulation taking into account PVL and 100%TAVI valve opening.In particular,the aorta without valve(AWoV)is assumed as the normal condition,whereas an aorta with TAVI 26 mm for 100%Geometrical Orifice Area(GOA)is considered as the patient aorta with PVL complication.A 3D patient-specific aorta model is elaborated using the MIMICS software.Implantation of the identical TAVI valve of Edward SAPIEN XT 26(Edwards Lifes ciences,Irvine,California)is considered.An undersized 26 mm TAVI valve with 100%valve opening is selected to mimic the presence of PVL at the aortic annulus.The present research indicates that the existence of PVL can increase the blood velocity,pressure drop and WSS in comparison to normal conditions,thereby paving the way to the development of recirculation flow,thrombus formation,aorta wall collapse,aortic rupture and damage of endothelium.

Clinical and prognostic implications of atrial fibrillation in patients undergoing transcatheter aortic valve implantation

AIM: To study a cohort of consecutive patients under-going transcatheter aortic valve implantation (TAVI) and compare the outcomes of atrial fibrillation (AF) patients vs patients in sinus rhythm (SR). METHODS: All consecutive patients undergoing TAVI in our hospital were included. The AF group comprised patients in AF at the time of TAVI or with history of AF, and were compared with the SR group. Procedural, echocardiographic and follow-up variables were compared. Likewise, the CHA 2 DS 2-VASC stroke risk score and HAS-BLED bleeding risk score and antithrombotic treatment at discharge in AF patients were compared with that in SR patients. RESULTS: From a total of 34 patients undergoing TAVI, 17 (50%) were allocated to the AF group, of whom 15 (88%) were under chronic oral anticoagulation. Patients in the AF group were similar to those in the SR group except for a trend (P = 0.07) for a higher logistic EuroSCORE (28% vs 19%), and a higher prevalence of hypertension (82% vs 53%) and chronic renal failure (17% vs 0%). Risk of both stroke and bleeding was high in the AF group (mean CHA 2 DS 2-VASC 4.3, mean HAS-BLED 2.9). In the AF group, treatment at discharge included chronic oral anticoagulation in all except one case, and in association with an antiplatelet drug in 57% of patients. During a mean follow-up of 11 mo (maximum 32), there were only two strokes, none of them during the peri-procedural period: one in the AF group at 30 mo and one in the SR group at 3 mo. There were no statistical differences in procedural success, and clinical outcome (survival at 1 year 81% vs 74% in AF and SR groups, respectively, P = NS). CONCLUSION: Patients in AF undergoing TAVI show a trend to a higher surgical risk. However, in our cohort, patients in AF did not have a higher stroke rate compared to the SR group, and the prognosis was similar in both groups.

Percutaneous management of vascular access in transfemoral transcatheter aortic valve implantation

Transcatheter aortic valve implantation(TAVI) using stent-based bioprostheses has recently emerged as a promising alternative to surgical valve replacement in selected patients. The main route for TAVI is retrograde access from the femoral artery using large sheaths(16-24 F). Vascular access complications are a clinically relevant issue in TAVI procedures since they are reported to occur in up to one fourth of patients and are strongly associated with adverse outcomes. In the present paper, we review the different types of vascular access site complications associated with transfemoral TAVI. Moreover, we discuss the possible optimal management strategies with particular attention to the relevance of early diagnosis and prompt treatment using endovascular techniques.

The role of echocardiography and CT angiography in transcatheter aortic valve implantation patients

The transcatheter aortic valve implantation （TAVI） consist an altemative treatment in patients with severe aortic stenosis. Multimodality imaging using transthoracic echocardiography （TTE） or transesophageal echocardiography （TOE） and multislice CT （MSCT） constitute cornerstone techniques for the pre-operative management, peri-procedural guidance, follow up and recognition of possible transcatheter valve related complications. CT angiography is much more accurate regarding the total definition of aortic annulus diameter and circumferential area. Two-dimensional （2D） echocardiography, underestimates the aortic valve annulus diameter compared to 3D imaging techniques （MSCT, MRI and 3D TOE）. Three-dimensional TOE imaging provides measurements of the aortic valve annulus similar to those delivered by MSCT. The pre-procedural MSCT constitutes the gold standard modality minimizing the presence of paravalvular aortic regurgitation, one of the most frequent complications. TOE/TTE and MSCT performance could predict the possibility of pacemaker implantation post-procedural. The presence of a new transient or persisting MR can be assessed well by TOE. Both TTE and TOE, consist initially the basic examination for post TAVI evaluation. In case of transcatheter heart valve failure, the MSCT could be used as additional imaging technique.

Effect of transcatheter aortic valve implantation on QT dispersion in patients with aortic stenosis

Background QT dispersion （QTd） is a predictor of ventricular arrhythmia. Ventricular arrhythmia is an important factor influencing morbidity and mortality in patients with aortic stenosis. Surgical aortic valve replacement reduced the QTd in this patients group. However, the effect of transcatheter aortic valve implantation （TAVI） on QTd in patients with aortic stenosis is unknown. The aim of this study was to investigate the effect of TAVI on QTd in patients with aortic stenosis. Methods Patients with severe aortic stenosis, who were not candi-dates for surgical aortic valve replacement due to contraindications or high surgical risk, were included in the study. All patients underwent electrocardiographic and echocardiographic evaluation before, and at the 6th month after TAVI, computed QTd and left ventricular mass index （LVMI）. Results A total 30 patients were admitted to the study （mean age 83.2 ± 1.0 years, female 21 and male 9, mean valve area 0.7 ± 3 mm2）. Edwards SAPIEN heart valves, 23 mm （21 patients） and 26 mm （9 patients）, by the transfemoral approach were used in the TAVI procedures. All TAVI procedures were successful. Both QTd and LVMI at the 6th month after TAVI were significantly reduced com-pared with baseline values of QTd and LVMI before TAVI （73.8 ± 4 ms vs. 68 ± 2 ms, P=0.001 and 198 ± 51 g/m2 vs. 184 ± 40 g/m2, P=0.04, respectively）. There was a significant correlation between QTd and LVMI （r=0.646, P〈0.001）. Conclusions QTd, which malign ventricular arrhythmia marker, and LVMI were significantly reduced after TAVI procedure. TAVI may decrease the possibility of ventricu-lar arrhythmia in patients with aortic stenosis.

Transcatheter aortic valve implantation： a revolution in the therapy of elderly and high-risk patients with severe aortic stenosis

Transcatheter aortic valve implantation （TAV1） represents a real revolution in the field of interventional cardiology for the treatment of elderly or high-risk surgical patients with severe symptomatic aortic valve stenosis. Today, TAVI seems to play a key and a reliable role in the treatment of intermediate and maybe low-risk patients with severe aortic stenosis. TAVI has also evolved from a complex and hazardous procedure into an effective and safe therapy by the development of new generation devices. This article aims to review the background and future of TAVI, elinieal trials and registries with old and new generation TAVI devices and to focus on some open issues related to post-procedural outcomes.

Long-term follow-up of quality of life in high-risk patients undergoing transcatheter aortic valve implantation for symptomatic aortic valve stenosis

Background Transcatheter aortic valve implantation （TAVI） has become the standard treatment for patients with severe symptomatic aortic stenosis （AS） considered at very high risk for surgical aortic valve replacement. The purpose of this sub-study was to evaluate long-term （〉 4 years） health-related quality of life （QoL） in octogenarians who underwent TAVI. Methods A single center observational registry in twenty patients who underwent frame analysis assessment ≥ 4 years after TAVI. Health-related QoL was evaluated, using the Short Form-36 （SF-36）, the EuroQoL-5D （EQ-5D） and the visual analogue score （EQ-VAS） questionnaires. Results The mean SF-36 subscale scores at follow-up were physical functioning 40.8 ± 26.3, role physical functioning 67.7 ± 34.9, vitality 54.6 ± 21.6, general health 52.1 ± 20.4, social functioning 63.8 ± 37.7, role emotional functioning 70.2 ± 36.0, mental health 73.2 ± 23.3 and bodily pain 80.9 ± 22.9. The mean EQ-VAS score 〉 4 years after TAVI was 64.7 ± 15.1. With respect to functional class, 80% of the patients were in NYHA class I/II at follow-up compared to 15% prior to TAVI. Conclusions This sub-study reports a significant improvement in functional class （NYHA） in a selected group of very elderly patients 〉 4 years after TAVI. Furthermore, all patients showed a satisfactory QoL despite their age and multiple comorbidities. In addition, our study reveals a lower QoL when compared with the general age matched Dutch population.

Impact of age on transcatheter aortic valve implantation outcomes：a comparison of patients aged≤ 80 years versus patients ＆gt; 80 years

ObjectiveTo investigate the procedural outcomes and the long-term survival of patients undergoing transcatheter aortic valve implantation （TAVI） and compare study results of patients≤ 80 years and patients ＆gt; 80 years old.MethodsA total of 240 patients treated with TAVI were divided into two groups according to age≤ 80 years （n = 105; 43.8%） and ＆gt; 80 years （n= 135; 56.2%）. The baseline characteristics and the pro-cedural outcomes were compared between these two groups of patients.ResultsWith the exception of peripheral artery disease and hypercho-lesterolemia, which were more frequently observed in the older age group, baseline characteristics were comparable between groups. Complica-tion rates did not differ significantly between patients≤ 80 years and patients ＆gt; 80 years. There were no differences in 30-day mortality rates be-tween patients aged≤ 80 years and patients ＆gt; 80 years old （9.5%vs. 7.4%, respectively;P = 0.557）. After a median follow-up of 28 months （in-terquartile range： 16-42 months）, 50 （47.6%） patients aged≤ 80 years died compared to 57 （42%） deaths in the group of patients ＆gt; 80 years old （P= 0.404）.ConclusionThe results of the present single center study showed that age did not significantly impact the outcomes of TAVI.

Impact of clinical and procedural factors upon C reactive protein dynamics following transcatheter aortic valve implantation

AIM: To determine the effect of procedural and clinical factors upon C reactive protein(CRP) dynamics following transcatheter aortic valve implantation(TAVI).METHODS: Two hundred and eight consecutive patients that underwent transfemoral TAVI at two hospitals(Imperial, College Healthcare NHS Trust, Hammersmith Hospital, London, United Kingdom and San Raffaele Scientific Institute, Milan, Italy) were included. Daily venous plasma CRP levels were measured for up to 7 d following the procedure(or up to discharge). Procedural factors and 30-d safety outcomes according tothe Valve Academic Research Consortium 2 definition were collected. RESULTS: Following TAVI, CRP significantly increased reaching a peak on day 3 of 87.6 ± 5.5 mg/d L, P < 0.001. Patients who developed clinical signs and symptoms of sepsis had significantly increased levels of CRP(P < 0.001). The presence of diabetes mellitus was associated with a significantly higher peak CRP level at day 3(78.4 ± 3.2 vs 92.2 ± 4.4, P < 0.001). There was no difference in peak CRP release following balloonexpandable or self-expandable TAVI implantation(94.8 ± 9.1 vs 81.9 ± 6.9, P = 0.34) or if post-dilatation was required(86.9 ± 6.3 vs 96.6 ± 5.3, P = 0.42), however, when pre-TAVI balloon aortic valvuloplasty was performed this resulted in a significant increase in the peak CRP(110.1 ± 8.9 vs 51.6 ± 3.7, P < 0.001). The development of a major vascular complication did result in a significantly increased maximal CRP release(153.7 ± 11.9 vs 83.3 ± 7.4, P = 0.02) and there was a trend toward a higher peak CRP following major/lifethreatening bleeding(113.2 ± 9.3 vs 82.7 ± 7.5, P = 0.12) although this did not reach statistical significance. CRP was not found to be a predictor of 30-d mortality on univariate analysis. CONCLUSION: Careful attention should be paid to baseline clinical characteristics and procedural factors when interpreting CRP following TAVI to determine their future management.

Health-related quality of life following transcatheter aortic valve implantation using transaortic, transfemoral approaches and surgical aortic valve replacement-a single-center study

Objective To evaluate short- and long-term changes in quality of life (QoL) in patients undergoing transcatheter aortic valve implantation (TAVI) and to assess differences in patient QoL when using the TAVI transaortic (TAVI TAo) approach compared with the transfemoral approach (TAVI TF) and surgical aortic valve replacement (SAVR). Methods Ninety-seven patients were assessed. Thirty-two patients underwent TAVI TAo, 31 underwent TAVI TF and 34 patients underwent SAVR. QoL was assessed using the EQ-5D-3L questionnaire at baseline, after one month and one year. Results Mean patient age was 80 years (range, 61–92 years) and the mean logistic EuroSCORE was 12.45%(range, 1.39%?78.98%). Declared health state at baseline was significantly lower in TAVI TF (P < 0.001) and after one month there were no differences between the three groups (P = 0.99). After one year, SAVR patient results of the EQ-5D-3L index value were lower in comparison to both TAVI patient groups (P < 0.05). The analysis also showed significant differences between the results of EQ-5D-3L index value over the one month and one year follow-up (TAVI TAo, P < 0.001;TAVI TF, P < 0.05;SAVR, P < 0.05). In all groups, the values significantly increased after one-month and one-year of follow-up in comparison to baseline value. Significant differences were also demonstrated between Visual Analogue Scale values (VAS). Conclusions A significant improvement in QoL was observed in all three patient groups. Regardless of the TAVI approach, EQ-5D-3L and VAS values were significantly increased after one-month and one-year follow up;the SAVR patients however, reported lower health status when compared to the TAVI patients.

Prognostic value of the ratio between prosthesis area and indexed annulus area measured by MultiSlice-CT for transcatheter aortic valve implantation procedures

Background Postprocedural aortic regurgitations following transcatheter aortic valve implantation （TAVI） procedures remain an is- sue. Benefit of oversizing strategies to prevent them isn＇t well established. We compared different level of oversizing in our cohort of con- secutive patients to address if severe oversizing compared to normal sizing had an impact on post-procedural outcomes. Methods From January 2010 to August 2013, consecutive patients were referred for TAVI with preoperative Multislice-CT （MSCT） and the procedures were achieved using Edwards Sapien~ or Corevalve devices~. Retrospectively, according to pre-procedural MSCT and the valve size, pa- tients were classified into three groups： normal, moderate and severe oversizing; depending on the ratio between the prosthesis area and the annulus area indexed and measured on MSCT. Main endpoint was mid-term mortality and secondary endpoints were the Valve Academic Research Consortium （VARC-2） endpoints. Results Two hundred and sixty eight patients had a MSCT and underwent TAVI procedure, with mainly Corevalve~. While all-cause and cardiovascular mortality rates were similar in all groups, post-procedural new pacemaker （PM） implantation rate was significantly higher in the severe oversizing group （P = 0.03）, while we observed more in-hospital congestive heart-failure （P = 0.02） in the normal sizing group. There was a trend toward more moderate to severe aortic regurgitation （AR） in the normal sizing group （P = 0.07）. Conclusions Despite a higher rate of PM implantation, oversizing based on this ratio reduces aortic leak with lower rates of post-procedural complications and a similar mid-term survival.

Defective recovery of QT dispersion following transcatheter aortic valve implantation： frequency, predictors and prognosis

Background Corrected QT dispersion （cQTD） has been correlated with non-uniform ventricular repolarisation and increased mortality. In patients with aortic stenosis, cQTD has been shown improved after surgical valve replacement, but the effects of transcatheter aortic valve implantation （TAVI） are unknown. Therefore, we sought to explore the frequency, predictors and prognostic effects of defective cQTD recovery at 6 months after TAVI. Methods A total of 222 patients underwent TAVI with the Medtronic-CoreValve System between November 2005 and January 2012. Patients who were on class Ⅰ or Ⅲ antiarrhythmics or on chronic haemodialysis or who developed atrial fibrillation, a new bundle branch block or became pacemaker dependent after TAVI were excluded. As a result, pre-, post- and follow-up ECG （median： 6 months） analysis was available in 45 eligible patients. Defective cQTD recovery was defined as any progression beyond the baseline cQTD at 6 months. Results In the 45 patients, the mean cQTD was 47 ± 23 ms at baseline, 45 ±17 ms immediately after TAVI and 40 ± 16 ms at 6 months （15% reduction, P = 0.049）. Compared to baseline, cQTD at 6 months was improved in 60% of the patients whereas defective cQTD recovery was present in 40%. cQTD increase immediately after TAVI was an independent predictor of defective cQTD recovery at 6 months （per 10 ms increase; OR： 1.89, 95% CI： 1.15-3.12）. By univariable analysis, defective cQTD recovery was associated with late mortality （HR： 1.52, 95% CI： 1.05-2.17）. Conclusions Despite a gradual reduction ofcQTD after TAVI, 40% of the patients had defective recovery at 6 months which was associated with late mortality. More detailed ECG analysis after TAVI may help to avoid late death.