Adverse impact of bleeding and transfusion on the outcome post-transcatheter aortic valve implantation: insights from the Pooled-RotterdAm-Milano-Toulouse In Collaboration Plus (PRAGMATIC Plus) initiative

Meta-analysis of Predictors of Early Severe Bleeding in Patients Who Underwent Transcatheter Aortic Valve Implantation

Severe bleeding (SB) in patients who underwent transcatheter aortic valve implantation (TAVI) could be fatal. Although multiple independent predictors of bleeding post-TAVI have been identified, the definitions of bleeding and predictors vary across studies. This study aimed to provide summary effect estimates for predictors of SB within 30 days post-TAVI. A systematic review of studies that reported the incidence of bleeding post-TAVI with raw data for predictors of interest was performed. Data on characteristics of study, patient, and procedure were extracted. Crude risk ratios (RRs) and 95% confidence intervals were calculated using random-effect model. Fifteen predictors on 65,209 patients from 47 studies were analyzed. The median rate of SB was 11% across studies. Seven factors (3 patient related and 4 procedure related) were recognized as predictors of early SB post-TAVI. Age ≥90 years (RR 1.17; p = 0.008), female (RR 1.13; p = 0.01), and sheath diameter >19 Fr (RR 1.19; p = 0.04) were weak predictors. Chronic kidney disease (RR 1.94; p <0.001) and transapical (TA) (RR 1.82; p <0.001) were moderate predictors that were almost associated with twofold risk. Vascular complication (RR 2.97; p <0.001) and circulatory support (RR 3.39; p <0.001) were strong predictors that were nearly associated with threefold risk. In conclusion, age, gender, chronic kidney disease, TA, sheath diameter, vascular complication, and circulatory support were all predictors of early SB post-TAVI in this meta-analysis, which provided possible guidance for prevention and management of SB related to TAVI.

Impact of sleep apnea on in-hospital outcomes after transcatheter aortic valve replacement: insight from National Inpatient Sample database 2011-2014

BACKGROUND

Sleep apnea is associated with worse outcomes following various kinds of surgeries. There is a paucity of data on the association of sleep apnea with clinical outcomes after transcatheter aortic valve replacement (TAVR).

METHODS

We used National Inpatient Sample (NIS) data 2011-2014 to identify patients undergoing TAVR. Association between sleep apnea and in-hospital postoperative outcomes were assessed by multivariate logistic regression and 1:1 propensity score matching analyses.

RESULTS

Of 42,189 patients who received TAVR, 4,605 patients (10.9%) had sleep apnea. Patients with sleep apnea were more likely to be younger and male with higher prevalences of hypertension, diabetes mellitus, dyslipidemia, chronic kidney disease, pulmonary hypertension and obesity who less frequently received transapical access than those without sleep apnea. The group with sleep apnea had less bleeding requiring transfusion (8.6% vs. 11.9%, P=0.01) than the counterpart. After adjusting for confounders, the presence of sleep apnea was no longer independently associated with any of the studied outcomes including all-cause mortality (OR 0.95; 95% CI: 0.64-1.42), stroke (OR 1.08; 95% CI: 0.65-1.81), myocardial infarction (OR 0.66; 95% CI: 0.36-1.22), acute respiratory failure (OR 0.94; 95% CI: 0.72-1.23), pneumothorax (OR 0.64; 95% CI: 0.26-1.59), vascular complication (OR 0.91; 95% CI: 0.69-1.22), bleeding requiring transfusion (OR 0.85; 95% CI: 0.65-1.11), acute kidney injury requiring hemodialysis (OR 0.94; 95% CI: 0.53-1.66) and permanent pacemaker implantation (OR 1.12; 95% CI: 0.87-1.43). The length and cost of hospital stay were not affected by sleep apnea, either.

CONCLUSIONS

With a prevalence of 10.9%, the presence of sleep apnea was not independently associated with postoperative in-hospital outcomes in patients undergoing TAVR in NIS data 2011 to 2014.

Incidence and risk factors of acute kidney injury following transcatheter aortic valve replacement

AIM

This study aimed to determine the incidence and risk factors of acute kidney injury (AKI) following transcatheter aortic valve replacement (TAVR).

METHODS

We included all adult patients undergoing TAVR for aortic stenosis from 1 January 2008 to 30 June 2014 at a tertiary referral hospital. AKI was defined based on Kidney Disease: Improving Global Outcomes criteria. We performed a multivariate logistic regression to identify factors associated with post-procedural AKI occurrence.

RESULTS

Three hundred eighty-six patients met the inclusion criteria, of which 106 (28%) developed AKI. In multivariate analysis, AKI development was independently associated with a transapical approach (odds ratio (OR), 2.81; 95% confidence interval (CI), 1.72-4.65 compared with transfemoral approach) and the need for an intra-aortic balloon pump (OR, 9.11; 95% CI, 1.77-68.29). Higher baseline renal function (OR, 0.78 per 10 mL/min per 1.73 m² increment in glomerular filtration rate; 95% CI, 0.68-0.87) was significantly associated with a decreased risk of AKI. After adjustment for the Society of Thoracic Surgeons' risk score, post-procedural AKI development remained significantly associated with an increased in-hospital (OR, 4.74; 95% CI, 1.39-18.48) and 6-month mortality (OR, 4.66; 95% CI, 2.32-9.63).

CONCLUSION

In a cohort of patients undergoing TAVR for aortic stenosis, AKI commonly occurred and was significantly associated with increased mortality. Baseline renal function, procedure approach and the need for circulatory support were important predictive factors for post-procedural AKI occurrence.

Risk Factors for Post-TAVI Bleeding According to the VARC-2 Bleeding Definition and Effect of the Bleeding on Short-Term Mortality: A Meta-analysis

BACKGROUND

In this study we investigated the effect of post-transcatheter aortic valve implantation (TAVI) bleeding (per Valve Academic Research Consortium-2 [VARC-2] bleeding criteria) on 30-day postoperative mortality and examined the correlation between pre- or intraoperative variables and bleeding.

METHODS

Multiple electronic literature databases were searched using predefined criteria, with bleeding defined per Valve Academic Research Consortium-2 criteria. A total of 10 eligible articles with 3602 patients were included in the meta-analysis.

RESULTS

The meta-analysis revealed that post-TAVI bleeding was associated with a 323% increase in 30-day postoperative mortality (odds risk [OR]; 4.23, 95% confidence interval [CI], 2.80-6.40; P < 0.0001) without significant study heterogeneity or publication bias. In subgroup analysis we found that patients with major bleeding/life-threatening bleeding showed a 410% increase in mortality compared with patients without bleeding (OR, 5.10; 95% CI, 3.17-8.19; P < 0.0001). Transapical access was associated with an 83% increase in the incidence of bleeding compared with transfemoral access (OR, 1.83; 95% CI, 1.43-2.33; P < 0.0001). Multiple logistic regression analysis revealed that atrial fibrillation (AF) was independently correlated with TAVI-associated bleeding (OR, 2.63; 95% CI, 1.33-5.21; P = 0.005). Meta-regression showed that potential modifiers like the Society of Thoracic Surgeons (STS) score, mortality, the logistic European System for Cardiac Operative Risk Evaluation (EuroSCORE), aortic valve area, mean pressure gradient, left ventricular ejection fraction, preoperative hemoglobin and platelet levels, and study design had no significant effects on the results of the meta-analysis.

CONCLUSIONS

Post-TAVI bleeding, in particular, major bleeding/life-threatening bleeding, increased 30-day postoperative mortality. Transapical access was a significant bleeding risk factor. Preexisting AF independently correlated with TAVI-associated bleeding, likely because of AF-related anticoagulation. Recognition of the importance and determinants of post-TAVI bleeding should lead to strategies to improve outcomes.

A Randomized Evaluation of the SAPIEN XT Transcatheter Heart Valve System in Patients With Aortic Stenosis Who Are Not Candidates for Surgery

OBJECTIVES

The purpose of this study was to determine the safety and effectiveness of the SAPIEN XT versus SAPIEN systems (Edwards Lifesciences, Irvine, California) in patients with symptomatic, severe aortic stenosis (AS) who were not candidates for surgery.

BACKGROUND

Transcatheter aortic valve replacement (TAVR) has become the standard of care for inoperable patients with severe, symptomatic AS. In the PARTNER (Placement of Aortic Transcatheter Valves) IB trial, a reduction in all-cause mortality was observed in patients undergoing TAVR with the balloon-expandable SAPIEN transcatheter heart valve compared with standard therapy, but the SAPIEN valve was associated with adverse periprocedural complications, including vascular complications, major bleeding, and paravalvular regurgitation. The newer, low-profile SAPIEN XT system was developed to reduce these adverse events.

METHODS

A total of 560 patients were enrolled at 28 sites in the United States from April 2011 to February 2012. Patients were randomized to receive the SAPIEN or SAPIEN XT systems. The primary endpoint was a nonhierarchical composite of all-cause mortality, major stroke, and rehospitalization at 1 year in the intention-to-treat population, assessed by noninferiority testing. Pre-specified secondary endpoints included cardiovascular death, New York Heart Association functional class, myocardial infarction, stroke, acute kidney injury, vascular complications, bleeding, 6-min walk distance, and valve performance (by echocardiography).

RESULTS

Both overall and major vascular complications were higher at 30 days in patients undergoing TAVR with SAPIEN compared with SAPIEN XT (overall: 22.1% vs. 15.5%; p = 0.04; major: 15.2% vs. 9.5%; p = 0.04). Bleeding requiring blood transfusions was also more frequent with SAPIEN compared with SAPIEN XT (10.6% vs. 5.3%; p = 0.02). At 1-year follow-up, the nonhierarchical composite of all-cause mortality, major stroke, or rehospitalization was similar (37.7% SAPIEN vs. 37.2% SAPIEN XT; noninferiority p value <0.002); no differences in the other major pre-specified endpoints were found.

CONCLUSIONS

In inoperable patients with severe, symptomatic AS, the lower-profile SAPIEN XT is noninferior to SAPIEN with fewer vascular complications and a lesser need for blood transfusion. (The PARTNER II Trial: Placement of AoRTic TraNscathetER Valves; NCT01314313).

Association of blood transfusion with acute kidney injury after transcatheter aortic valve replacement: A meta-analysis

AIM

To assess red blood cell (RBC) transfusion effects on acute kidney injury (AKI) after transcatheter aortic valve replacement (TAVR).

METHODS

A literature search was performed using MEDLINE, EMBASE, Cochrane Database of Systematic Reviews, and clinicaltrials.gov from the inception of the databases through December 2015. Studies that reported relative risk, odds ratio or hazard ratio comparing the risks of AKI following TAVR in patients who received periprocedural RBC transfusion were included. Pooled risk ratio (RR) and 95%CI were calculated using a random-effect, generic inverse variance method.

RESULTS

Sixteen cohort studies with 4690 patients were included in the analyses to assess the risk of AKI after TAVR in patients who received a periprocedural RBC transfusion. The pooled RR of AKI after TAVR in patients who received a periprocedural RBC transfusion was 1.95 (95%CI: 1.56-2.43) when compared with the patients who did not receive a RBC transfusion. The meta-analysis was then limited to only studies with adjusted analysis for confounders assessing the risk of AKI after TAVR; the pooled RR of AKI in patients who received periprocedural RBC transfusion was 1.85 (95%CI: 1.29-2.67).

CONCLUSION

Our meta-analysis demonstrates an association between periprocedural RBC transfusion and a higher risk of AKI after TAVR. Future studies are required to assess the risks of severe AKI after TAVR requiring renal replacement therapy and mortality in the patients who received periprocedural RBC transfusion.

Routine Endovascular Treatment With a Stent Graft for Access-Site and Access-Related Vascular Injury in Transfemoral Transcatheter Aortic Valve Implantation

Background—

Access-site and access-related vascular injury (ASARVI) is still a major limiting factor in transcatheter aortic valve implantation and affects the outcome of patients. Management strategies for ASARVI include manual compression, stent grafts, and vascular surgery. We hypothesized that the standard use of a self-expanding stent graft for the management of ASARVI is feasible and safe.

Methods and Results—

Of 407 patients treated by transfemoral transcatheter aortic valve implantation, 110 experienced ASARVI (27.0%). Of these, 96 (87.3%) were managed by the implantation of a self-expanding nitinol stent graft. In the majority of patients, minor vascular complications triggered the implantation of a stent graft (86.5%), mainly because of bleeding (90.6%) and dissection (5.2%) of the common femoral artery with high rates of primary treatment success (97.9%). Patients receiving stent grafts were more often female (62.2 versus 45.6%, P <0.01), had higher body mass indices (27.8±6.7 versus 25.7±4.7, P =0.01), and suffered more often from diabetes mellitus (34.4 versus 24.5%, P =0.04). Angiographic assessment after a median follow-up of 345 days (interquartile range, 23–745 days) revealed only one patient with moderate, asymptomatic instent-stenosis (1.0%). Compared with a propensity score–matched cohort of patients without ASARVI, stented patients had comparable long-term mortality, despite the occurrence of a vascular complication (1-year mortality: 17.7% versus 26.6%; stent versus matched cohort, respectively; P =0.1).

Conclusions—

Routine use of a self-expanding nitinol stent graft in selected patients experiencing ASARVI after transcatheter aortic valve implantation is feasible, safe, and associated with favorable short- and midterm clinical outcome.

Transcatheter Aortic Valve Implantation and Morbidity and Mortality-Related Factors: a 5-Year Experience in Brazil

Background

Transcatheter aortic valve implantation has become an option for high-surgical-risk patients with aortic valve disease.

Objective

To evaluate the in-hospital and one-year follow-up outcomes of transcatheter aortic valve implantation.

Methods

Prospective cohort study of transcatheter aortic valve implantation cases from July 2009 to February 2015. Analysis of clinical and procedural variables, correlating them with in-hospital and one-year mortality.

Results

A total of 136 patients with a mean age of 83 years (80-87) underwent heart valve implantation; of these, 49% were women, 131 (96.3%) had aortic stenosis, one (0.7%) had aortic regurgitation and four (2.9%) had prosthetic valve dysfunction. NYHA functional class was III or IV in 129 cases (94.8%). The baseline orifice area was 0.67 ± 0.17 cm² and the mean left ventricular-aortic pressure gradient was 47.3±18.2 mmHg, with an STS score of 9.3% (4.8%-22.3%). The prostheses implanted were self-expanding in 97% of cases. Perioperative mortality was 1.5%; 30-day mortality, 5.9%; in-hospital mortality, 8.1%; and one-year mortality, 15.5%. Blood transfusion (relative risk of 54; p = 0.0003) and pulmonary arterial hypertension (relative risk of 5.3; p = 0.036) were predictive of in-hospital mortality. Peak C-reactive protein (relative risk of 1.8; p = 0.013) and blood transfusion (relative risk of 8.3; p = 0.0009) were predictive of 1-year mortality. At 30 days, 97% of patients were in NYHA functional class I/II; at one year, this figure reached 96%.

Conclusion

Transcatheter aortic valve implantation was performed with a high success rate and low mortality. Blood transfusion was associated with higher in-hospital and one-year mortality. Peak C-reactive protein was associated with one-year mortality.

Management strategies and future challenges for aortic valve disease

The management of aortic valve disease has been improved by accurate diagnosis and assessment of severity by echocardiography and advanced imaging techniques, efforts to elicit symptoms or objective markers of disease severity and progression, and consideration of optimum timing of aortic valve replacement, even in elderly patients. Prevalence of calcific aortic stenosis is growing in ageing populations. Conventional surgery remains the most appropriate option for most patients who require aortic valve replacement, but the transcatheter approach is established for high-risk patients or poor candidates for surgery. The rapid growth of transcatheter aortic valve replacement has been fuelled by improved technology, evidence-based clinical research, and setting up of multidisciplinary heart teams. Aortic regurgitation can be difficult to diagnose and quantify. Left ventricular dysfunction often precedes symptoms, needing active surveillance by echocardiography to determine the optimum time for aortic valve replacement. Development of transcatheter approaches for aortic regurgitation is challenging, owing to the absence of valvular calcification and distortion of aortic root anatomy in many patients.

Validation of the Valve Academic Research Consortium Bleeding Definition in Patients With Severe Aortic Stenosis Undergoing Transcatheter Aortic Valve Implantation

Background

The Valve Academic Research Consortium (VARC) has proposed a standardized definition of bleeding in patients undergoing transcatheter aortic valve interventions (TAVI). The VARC bleeding definition has not been validated or compared to other established bleeding definitions so far. Thus, we aimed to investigate the impact of bleeding and compare the predictivity of VARC bleeding events with established bleeding definitions.

Methods and Results

Between August 2007 and April 2012, 489 consecutive patients with severe aortic stenosis were included into the Bern‐TAVI‐Registry. Every bleeding complication was adjudicated according to the definitions of VARC, BARC, TIMI, and GUSTO. Periprocedural blood loss was added to the definition of VARC, providing a modified VARC definition. A total of 152 bleeding events were observed during the index hospitalization. Bleeding severity according to VARC was associated with a gradual increase in mortality, which was comparable to the BARC, TIMI, GUSTO, and the modified VARC classifications. The predictive precision of a multivariable model for mortality at 30 days was significantly improved by adding the most serious bleeding of VARC (area under the curve [AUC], 0.773; 95% confidence interval [CI], 0.706 to 0.839), BARC (AUC, 0.776; 95% CI, 0.694 to 0.857), TIMI (AUC, 0.768; 95% CI, 0.692 to 0.844), and GUSTO (AUC, 0.791; 95% CI, 0.714 to 0.869), with the modified VARC definition resulting in the best predictivity (AUC, 0.814; 95% CI, 0.759 to 0.870).

Conclusions

The VARC bleeding definition offers a severity stratification that is associated with a gradual increase in mortality and prognostic information comparable to established bleeding definitions. Adding the information of periprocedural blood loss to VARC may increase the sensitivity and the predictive power of this classification.

Antiplatelet therapy following transcatheter aortic valve implantation

OBJECTIVE

There is limited evidence to support decision making on antiplatelet therapy following transcatheter aortic valve implantation (TAVI). Our aim was to assess the efficacy and safety of aspirin-only (ASA) versus dual antiplatelet therapy (DAPT) following TAVI.

METHODS

We performed a systematic review and pooled analysis of individual patient data from 672 participants comparing single versus DAPT following TAVI. Primary endpoint was defined as the composite of net adverse clinical and cerebral events (NACE) at 1 month, including all-cause mortality, acute coronary syndrome (ACS), stroke, life-threatening and major bleeding.

RESULTS

At 30 days a NACE rate of 13% was observed in the ASA-only and in 15% of the DAPT group (OR 0.83, 95% CI 0.48 to 1.43, p=0.50). A tendency towards less life-threatening and major bleeding was observed in patients treated with ASA (OR 0.56, 95% CI 0.28 to 1.11, p=0.09). Also, ASA was not associated with an increased all-cause mortality (OR 0.91, 95% CI 0.36 to 2.27, p=0.83), ACS (OR 0.5, 95% CI 0.05 to 5.51, p=0.57) or stroke (OR 1.21; 95% CI 0.36 to 4.03, p=0.75).

CONCLUSIONS

No difference in 30-day NACE rate was observed between ASA-only or DAPT following TAVI. Moreover, a trend towards less life-threatening and major bleeding was observed in favour of ASA. Consequently the additive value of clopidogrel warrants further investigation.

The obesity paradox in patients undergoing transcatheter aortic valve implantation

BACKGROUND

Obesity is a major risk factor for cardiovascular morbidity and mortality. A considerable number of studies, however, showed better outcomes for overweight patients undergoing cardiovascular interventions-the so called obesity paradox.

HYPOTHESIS

Increased body mass index (BMI) is independently associated with improved survival following transcatheter aortic valve implantation (TAVI).

METHODS

We analyzed the data of 409 consecutive patients undergoing TAVI in our medical center. Patients were categorized into 4 groups according to BMI: underweight (≤18.4 kg/m(2) ), normal weight (18.5-24.9 kg/m(2) ), overweight (25-29.9 kg/m(2) ), and obese (≥30 kg/m(2) ). Procedure-related complications were recorded, as well as 30-day and 1-year all-cause mortality rates.

RESULTS

Obese patients had a higher prevalence of comorbidities and higher incidence of vascular complications compared with the normal-weight patients (16% vs 7%, P = 0.013). Nevertheless, 30-day mortality was similar among the groups, whereas 1-year mortality was lower among the overweight and obese patients (BMI >25) (P = 0.038). After adjusting for differences in baseline characteristics, increase in BMI was found to be independently associated with improved survival following TAVI (hazard ratio: 0.94, confidence interval: 0.89-0.99, P = 0.043).

CONCLUSIONS

In our single-center study, obesity and overweight were independently associated with better outcome, supporting the obesity paradox in the TAVI population.

Acute kidney injury after aortic valve replacement: incidence, risk factors and outcomes

The occurrence of acute kidney injury (AKI) following aortic valve replacement (AVR) has very serious clinical implications and has therefore been the focus of several studies. The authors report the results of previous studies evaluating both transcatheter AVR (TAVR) and indirectly surgical AVR (SAVR) through looking at cardiopulmonary bypass (CPB) cardiac surgeries, and identify the incidence, predictors and outcomes of AKI following AVR. In most studies, AKI was defined using the Risk, Injury, Failure, Loss and End Stage, Valve Academic Research Consortium (modified Risk, Injury, Failure, Loss and End Stage) or Valve Academic Research Consortium-2 (Acute Kidney Injury Network) AKI classification criteria. Twelve studies including more than 90,000 patients undergoing cardiac surgery on CPB were considered as well as 26 studies with more than 6000 patients undergoing TAVR. Depending on the definition used, AKI occurred in 3.4-43% of SAVR cases with up to 2.5% requiring dialysis, and in 3.4-57% of TAVR cases. Factors identified as independent predictors of AKI were: baseline kidney failure, EUROSCORE, diabetes mellitus, hypertension, chronic obstructive pulmonary disease, anemia, peripheral vascular disease, heart failure, surgical priority, CPB time, reoperation, use of intra-aortic balloon pump, need for re-exploration, contrast agent volume, transapical access, blood transfusion, postoperative thrombocytopenia, postoperative leukocytosis as well as demographic variables such as age and female gender. The 30-day mortality rate for patients with AKI following SAVR ranged from 5.5 to 46% and was 3- to 16-times higher than in those without AKI. Similarly, patients who developed AKI after TAVR had a mortality rate of 7.8-29%, which was two- to eight-times higher than those who did not suffer from AKI. AKI confers up to a fourfold increase in 1-year mortality. Finally, hospital length of stay was significantly increased in patients with AKI in both SAVR and TAVR groups, with increases up to 3- and 2.5-times, respectively.

Recovery from anemia in patients with severe aortic stenosis undergoing transcatheter aortic valve implantation--prevalence, predictors and clinical outcome

Introduction

Preoperative anemia is common in patients with severe aortic stenosis undergoing transcatheter aortic valve implantation (TAVI) and has been linked to a poorer outcome – including a higher 1-year mortality. The aim of this study was to investigate the impact of successful TAVI on baseline anemia.

Methods

A total of 253 patients who survived at least 1 year following TAVI were included in this study. The prevalence, predictors and clinical outcome of hemoglobin (Hb)-recovery were assessed.

Results

The prevalence of baseline anemia was 49% (n = 124) – recovery from anemia occurred in 40% of the anemic patients (n = 49) at 1 year after TAVI with an increase in mean Hb-level of 1.35 g/dL from baseline. This increase was not related to an improvement in renal function. At multivariate analysis, a high peak gradient (OR 4.82, P = 0.003) was shown to be an independent predictor for Hb-recovery, while blood transfusion (OR 0.31, P = 0.038) and chronic kidney disease (CKD, OR 0.33, P = 0.043) were identified as negative predictors at, respectively, one and two years after TAVI. When compared to patients without baseline anemia, those anemic patients with Hb-recovery had a similar functional improvement (OR 0.98, P = 0.975), whereas those without Hb-recovery had a significantly lower likelihood of functional improvement with ≧2 NYHA classes (OR 0.49, P = 0.034) and a higher likelihood of re-hospitalization within the first year after TAVI (OR 1.91, P = 0.024).

Conclusion

Recovery from anemia occurs in 40% of anemic patients at 1 year after TAVI – mainly in those with a high gradient and without CKD. Blood transfusion was found to have a transient adverse effect on this Hb-recovery. Finally, anemic patients without Hb-recovery experience less functional improvement and have a higher re-hospitalization rate within the first year after TAVI.

Transcatheter Aortic Valve Implantation (TAVI): Is it Time for This Intervention to be Applied in a Lower Risk Population?

Patients with severe aortic stenosis are sometimes not candidates for conventional open heart surgery because of severe deconditioning, excessive risk factors, and multiple comorbidities. Transcatheter aortic valve implantation (TAVI) is a relatively recent intervention, which was initially addressed to individuals with severe symptomatic aortic stenosis at substantial or prohibitive surgical risk. Despite the documented beneficial effects of this therapeutic intervention in certain carefully selected individuals, it has not yet been applied to lower risk patients. This is a review of the current literature and accumulated clinical data of this rapidly evolving invasive procedure in an attempt to resolve whether it can now be applied to a wider portion of patients with aortic stenosis.

AKI associated with cardiac surgery

Approximately 18% of patients undergoing cardiac surgery experience AKI (on the basis of modern standardized definitions of AKI), and approximately 2%-6% will require hemodialysis. The development of AKI after cardiac surgery portends poor short- and long-term prognoses, with those developing RIFLE failure or AKI Network stage III having an almost 2-fold increase in the risk of death. AKI is caused by a variety of factors, including nephrotoxins, hypoxia, mechanical trauma, inflammation, cardiopulmonary bypass, and hemodynamic instability, and it may be affected by the clinician's choice of fluids and vasoactive agents as well as the transfusion strategy used. The risk of AKI may be ameliorated by avoidance of nephrotoxins, achievement of adequate glucose control preoperatively, and use of goal-directed therapy hemodynamic strategies. Remote ischemic preconditioning is an exciting future strategy, but more work is needed before widespread implementation. Unfortunately, there are no pharmacologic agents known to reduce the risk of AKI or treat established AKI.

Impact of access on TAVI procedural and midterm follow-up: a meta-analysis of 13 studies and 10,468 patients

INTRODUCTION

Transcatheter aortic valve implantation (TAVI) may be performed using the transfemoral (TF) or transapical (TA) approach in most patients with aortic stenosis. The impact of access choice on peri-procedural and midterm results remains to be defined.

METHODS

Medline and Cochrane Library were searched for articles describing differences in baseline, peri-procedural, and midterm outcomes among patients undergoing TF or TA TAVI. The primary end-point was all-cause mortality after at least 1-year follow-up, while secondary end-points were 30 days mortality and in-hospital complications (bleeding and cerebrovascular events). The independent impact of access choice was evaluated with pooled analysis using a random-effect model.

RESULTS

Thirteen studies with 10,468 patients were included. TF was the most exploited strategy (69.5% vs. 30.5%). After adjusting for confounding variables, 30-day and midterm follow-up mortality (median 365 days, range 222-400) were lower in TF patients with a pooled adjusted odds ratio of 0.81 (0.68-0.97 I(2) 99%) and 0.85 (0.80-0.90 I(2) 96%), respectively. Regarding periprocedural outcomes, TF reduced risk of bleedings and strokes (OR of 0.74 [0.66-0.82 I(2) 95%] and 0.91 [0.83-0.99] I(2) 86%, respectively).

CONCLUSIONS

The TF approach reduces mortality in TAVI patients, due to lower rates of periprocedural bleedings and strokes.

The MitraClip experience and future percutaneous mitral valve therapies

Mitral regurgitation is the most common valve abnormality worldwide and its prevalence is expected to increase in the future due to aging of the population. Percutaneous mitral valve repair therapies may offer an opportunity to treat severe MR in the elderly or other high-risk groups who would otherwise be ineligible for surgery. The MitraClip system uses edge-to-edge coaptation of the mitral leaflets to create a double-orifice valve and reduce MR. It has been performed in over 10 000 patients to date, and as experience has improved, procedural times have shortened from over 200 minutes to less than 100 minutes, with increasing numbers of patients being left with ≤ grade 2+ MR. This review will focus on the literature available on MitraClip and other novel percutaneous techniques that are being developed for the treatment of severe MR.

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.

Predictors of clinical outcome in transfemoral TAVI: circumferential iliofemoral calcifications and manufacturer-derived recommendations

OBJECTIVE

This study aimed to investigate the predictive value of circumferential iliofemoral calcifications and current manufacturer recommendations, which are not evidence-based, in transfemoral (TF) transcatheter aortic valve implantation (TAVI).

METHODS

A patient cohort with a broad range of iliofemoral anatomies undergoing TF TAVI (n=132) were retrospectively divided as "suitable" (n=76, 58%) and "unsuitable" (n=56, 42%) candidates according to current recommendations. Iliofemoral angiography and reconstructed multislice CT (MSCT) images were used for access screening in the majority of patients.

RESULTS

Vessel properties were significantly worse in the "unsuitable group." The sheath-to-iliofemoral artery ratio (SIFAR) and calcium score were 1.35±0.2 and 1.7±0.8 in the unsuitable group, compared to 1.0±0.12 (p<0.0001) and 1.0±0.7 (p=0.0001) in the "suitable" patients. Major vascular complications (MVCs) occurred more frequently in the "unsuitable" group (10.7% vs. 2.6%, p=0.07) and were predicted by SIFAR [OR: 64, 95% CI: 1.4-2971, p=0.03] and circumferential iliofemoral calcifications [OR: 6, 95% CI: 1.2-26, p=0.025]. In the multivariate analysis, circumferential calcifications [HR: 3.6, 95% CI: 1-13.2, p=0.043] but not major vascular complications (MVCs) or manufacturer recommendations were associated with increased mortality.

CONCLUSION

According to our results, manufacturer recommendations are safe but overly conservative. Circumferential iliofemoral calcifications may provide independent prognostic information in patients undergoing TAVI.

Impact on prognosis of periprocedural bleeding after TAVI: mid-term follow-up of a multicenter prospective study

AIMS

Impact of periprocedural bleeding after transcatheter aortic valve implantation (TAVI) over mid-term prognosis remains still unclear.

METHODS

Consecutive patients who underwent TAVI from May 2008 to July 2012 were prospectively included and stratified according to life-threatening (LT) and major bleeding (MB). Mid-term all-cause death was the primary end-point, and 30-day death, vascular complications, stroke, and acute kidney injury the secondary ones. All end-points were adjudicated according to VARC.

RESULTS

Seven hundred fourteen patients with an average age of 81.9 ± 5.8 years were included. 130 (18%) patients suffered a LT, 112 (16%) a MB. A preprocedural GFR <30 ml/min and increasing diameter of sheaths were independent predictors of LT or MB, while transfemoral approach showed a protective effect (OR 0.42; CI: 0.26-0.68; P = 0.035). At 30 days LT (OR 3.3; CI: 1.1-9.7; P = 0.0026) and MB (OR 3.5; CI: 1.4-8.6; P = 0.007) bleeding along with GFR < 30 ml/min (OR 2.3; CI: 1.1-5.5; P = 0.04) were independent predictors of death, while bleeding did not impact survival on mid term (OR 0.9; CI: 0.47-1.7; P = 0.78; all CI 95%).

CONCLUSION

Periprocedural bleeding after TAVI was frequent and associated with an increased mortality after 30 days but not after mid-term follow-up. A preprocedural GFR < 30 ml/min was the most important predictor of bleeding, enabling risk stratification and choice of approach for these patients.

Antithrombotic therapy - predictor of early and long-term bleeding complications after transcatheter aortic valve implantation

INTRODUCTION

Dual antiplatelet therapy (DAPT) - aspirin and clopidogrel - is recommended after transcatheter aortic valve implantation (TAVI) without an evidence base. The main aim of the study was to estimate the impact of antithrombotic therapy on early and late bleeding. Moreover, we assessed the impact of patients' characteristics on early bleeding and the influence of bleeding on prognosis.

MATERIAL AND METHODS

Between 2009 and 2011, 83 consecutive TAVI patients, age 81.1 ±7.2 years, were included. Bleeding complications were defined by the Valve Academic Research Consortium (VARC) scale. The median follow-up was 12 ±15.5 months (range: 1 to 23) and included 68 (81.9%) patients.

RESULTS

Early bleeding occurred in 51 (61.4%) patients. Vitamin K antagonists (VKA) pre-TAVI (p = 0.001) and VKA + clopidogrel early post-TAVI (p = 0.04) were the safest therapies; in comparison to the safest one, peri-procedural DAPT (p = 0.002; p = 0.05) or triple anticoagulant therapy (TAT) (p = 0.003, p = 0.05) increased the risk for early bleeding. Predictors for early bleeding were: clopidogrel pre-TAVI (OR: 4.43, 95% CI: 1.02-19.24, p = 0.04), preceding percutaneous coronary intervention (PCI) (10.08, OR: 95% CI: 1.12-90.56, p = 0.04), anemia (OR: 4.00, 95% CI: 1.32-12.15, p = 0.01), age > 85 years (OR: 5.96, 95% CI: 1.47-24.13, p = 0.01), body mass index (BMI) (OR: 0.86, 95% CI: 0.74-0.99, p = 0.04). Late bleeding occurred in 35 patients (51.4%) on combined therapy, and none on VKA or clopidogrel monotherapy (p = 0.04). Bleeding complications did not worsen the survival.

CONCLUSIONS

This study seems to suggest that advanced age, BMI, and a history of anemia increased the risk for early bleeding after TAVI. Clopidogrel pre-TAVI should be avoided; therefore, time of preceding PCI should take into account discontinuation of clopidogrel in the pre-TAVI period. Vitamin K antagonists with clopidogrel seems to be the safest therapy in the early post-TAVI period, similarly as VKA/clopidogrel monotherapy in long-term prophylaxis.

Cardiovascular Collapse During Transcatheter Aortic Valve Replacement: Diagnosis and Treatment of the "Perilous Pentad"

Transcatheter aortic valve replacement (TAVR) has, without a doubt, brought an unprecedented excitement to the field of interventional cardiology. The avoidance of a sternotomy by transfemoral or transapical aortic-valve implantation appears to come at the price of some serious complications, including an increased risk of embolic stroke and paravalvular leakage. The technical challenges of the procedure and the complex nature of the high-risk patient cohort make the learning curve for this procedure a steep one, with the potential for unexpected complications always looming. Although most commonly relating to vascular access, these complications can also result from prosthesis-related trauma or malposition, or from unanticipated trauma from the pacing wire or the super stiff wire. Sudden and unexplained hypotension is often the earliest indicator of major complication and must prompt an immediate and detailed exclusion of five major pathologies: retroperitoneal bleeding from access site rupture, aortic dissection or rupture, pericardial tamponade, coronary ostial obstruction, or acute severe aortic regurgitation. In most cases, these can be dealt with quickly, and by percutaneous means, although open surgery may occasionally be necessary. Increased operator and team experience should make prevention and recognition of these catastrophic complications more complete. For this reason, the importance of specific training, such as that provided by the valve manufacturers through workshops and proctorship, cannot be overemphasized. It is essential that all operators, and indeed all members of the implant team, exert extreme vigilance to the development of intraprocedural complications, which could have rapid and potentially lethal consequences. Greater experience with an improved understanding of these risks, along with the development of better devices, deliverable through smaller and less traumatic sheath technology, will undoubtedly improve the safety and, potentially, widen the applicability of TAVR in the future. Forthcoming innovations include a newer generation of the valves with operator-controlled steerability to facilitate negotiation of tortuous aortic anatomy, as well as fully retrievable and resheathable devices to accommodate the events of dislocation or embolization. The fact that Transcatheter aortic valve implantation (TAVI) is new implies learning from experience but also from mistakes. The TAVI team must be vigilant to recognize and diagnose intraprocedure severe hypotension. The "perilous pentad" of catastrophic causes must be constantly borne in mind: retroperitoneal bleeding from access site rupture, aortic dissection or rupture, pericardial tamponade, coronary ostial obstruction, and acute severe aortic insufficiency.

Effect of severe left ventricular systolic dysfunction on hospital outcome after transcatheter aortic valve implantation or surgical aortic valve replacement: results from a propensity-matched population of the Italian OBSERVANT multicenter study

OBJECTIVE

Despite demonstration of the superior outcomes of transcatheter aortic valve implantation (TAVI) versus optimal medical therapy for severe left ventricular systolic dysfunction, studies comparing TAVI and surgical aortic valve replacement (AVR) in this high-risk group have been lacking.

METHODS

We performed propensity matching for age, gender, baseline comorbidities, previous interventions, priority at hospital admission, frailty score, New York Heart Association class, EuroSCORE, and associated cardiac diseases. Next, the 30-day mortality and procedure-related morbidity of 162 patients (81 TAVI vs 81 AVR) with severe left ventricular systolic dysfunction (ejection fraction ≤ 35%) were analyzed at the Italian National Institute of Health.

RESULTS

The 30-day mortality was comparable (P = .37) between the 2 groups. The incidence of periprocedural acute myocardial infarction (P = .55), low output state (P = .27), stroke (P = .36), and renal dysfunction (peak creatinine level, P = .57) was also similar between the 2 groups. TAVI resulted in significantly greater postprocedural permanent pacemaker implantation (P = .01) and AVR in more periprocedural transfusions (P < .01) despite a similar transfusion rate per patient (2.8 ± 3.7 for TAVI vs 4.4 ± 3.8 for AVR; P = .08). The postprocedural intensive care unit stay (median, 2 days after TAVI vs 3 days after AVR; P = .34), intermediate care unit stay (median, 0 days after both TAVI and AVR; P = .94), and hospitalization (median, 11 days after TAVI vs 14 days after AVR; P = .51) were comparable.

CONCLUSIONS

In patients with severe left ventricular systolic dysfunction, both TAVI and AVR are valid treatment options, with comparable hospital mortality and periprocedural morbidity. Comparisons of the mid- to long-term outcomes are mandatory.

Transapical versus transfemoral aortic valve implantation: a multicenter collaborative study

BACKGROUND

There are no direct comparisons between transapical aortic valve implantation (TA-AVI) and transfemoral aortic valve implantation (TF-AVI). Therefore, the aim of this study was to compare the short-term and midterm outcomes of TA-AVI versus TF-AVI.

METHODS

Data from four European centers were pooled and analyzed. To minimize differences between TA-AVI and TF-AVI multivariable analysis was used. Study endpoints were defined according to the Valve Academic Research Consortium-I criteria at 30 days and 1 year. Primary endpoints of this study were 30-day all-cause mortality and mortality during follow-up.

RESULTS

A total of 882 patients underwent TAVI, of whom 793 (89.9%) underwent TF-AVI and 89 (10.1%) underwent TA-AVI. Patients undergoing TA-AVI had a higher estimated risk of mortality as defined by the logistic European System for Cardiac Operative Risk Evaluation score (median 27.0, interquartile range [IQR]: 20.2 to 33.8 versus median 20.0, IQR: 12.3 to 27.7; p < 0.001) and The Society of Thoracic Surgeons Score (median 10.2, IQR: 5.3 to 9.9 versus median 6.7, IQR: 3.5 to 9.9; p < 0.001) and had more comorbidities. At 30 days, there was an increased risk of all-cause mortality in the TA-AVI group (odds ratio [OR] 3.12, 95% confidence interval [CI]: 1.43 to 6.82; p = 0.004). TF-AVI was associated with a higher frequency of major (OR 0.33, 95% CI: 0.12 to 0.90; p = 0.031) and minor vascular complications (OR 0.17, 95% CI: 0.04 to 0.71; p = 0.0015). In-hospital stay was significantly longer among patients undergoing TA-AVI (OR 2.29, 95% CI: 1.28 to 4.09; p = 0.05). During a median follow-up of 365 days (IQR: 174 to 557), TA-AVI was associated with an increased risk of all-cause mortality (hazard ratio 1.88, 95% CI: 1.23 to 2.87; p = 0.004).

CONCLUSIONS

In institutions performing a low volume of TA-AVI, the technique is associated with an increased risk of all-cause mortality and longer hospital stay but less vascular complications in comparison with TF-AVI. The interaction between experience and type of treatment on outcome requires further investigation before advocating one treatment over the other.

Mechanisms and management of TAVR-related complications

Patients with severe aortic stenosis who are at high surgical risk or not considered to be suitable candidates for surgical aortic valve replacement are increasingly being treated with transcatheter aortic valve replacement (TAVR). Although this novel treatment modality has been proven to be effective in this patient population, serious complications occur in approximately one-third of patients during the month after the procedure. Such events include myocardial infarction, cerebrovascular events, vascular complications, bleeding, acute kidney injury, valve regurgitation, valve malpositioning, coronary obstruction, and conduction disturbances and arrhythmias, which can all lead to death. Prevention of these complications should be based on patient screening and selection by a dedicated 'heart team' and the use of multimodality imaging. Anticipation and early recognition of these complications, followed by prompt management using a wide range of percutaneous or surgical rescue interventions, is vital to patient outcome. Continuous patient assessment and reporting of complications according to standardized definitions, in addition to growing operator experience and upcoming technological refinements, will hopefully reduce the future rate of complications related to this procedure.

Transcatheter aortic valve replacement with CoreValve

The treatment of aortic stenosis in high-risk surgical patients is now possible by transcatheter aortic valve replacement. The CoreValve is a new transcatheter valve with a unique design expanding its application in patients with aortic stenosis. The CoreValve is just completing clinical trial in the United States and not yet available for commercial use in the United States but is widely used in Europe.

A review of most relevant complications of transcatheter aortic valve implantation

Transcatheter aortic valve implantation (TAVI) has emerged for treating aortic stenosis in patients who are poor candidates for surgical aortic valve replacement. Currently, the balloon-expandable Edwards Sapien valve—which is usually implanted via a transfemoral or transapical approach—and the self-expanding CoreValve ReValving system—which is designed for retrograde application—are the most widely implanted valves worldwide. Although a promising approach for high-risk patients, the indication may be expanded to intermediate- and eventually low-risk patients in the future; however, doing so will require a better understanding of potential complications, risk factors for these complications, and strategies to individualize each patient to a different access route and a specific valve. This paper reviews the most relevant complications that may occur in patients who undergo catheter-based aortic valve implantation.

Maintaining a minimally invasive approach-vascular closure after trans-catheter aortic valve intervention

Trans-catheter aortic valve implantation (TAVI) is now recognised as an effective way to treat patients with symptomatic aortic stenosis when open surgical repair is not feasible or considered too high risk. Retrograde trans-femoral TAVI (TF-TAVI) requires large bore vascular access (18-24F), and successful management of the access site is key to maintaining the minimally invasive nature of the procedure. This editorial reviews the current techniques available to facilitate percutaneous vascular closure and the common complications associated with vascular access.