Overestimation of aortic valve replacement risk by EuroSCORE: implications for percutaneous valve replacement

[Percutaneous aortic valve implantation: results and perspectives]

As the French population is aging, a growing number of elderly patients with symptomatic severe aortic stenosis are going to require therapeutic management. Approximately 30 to 40% of these patients do not undergo surgical treatment and a high proportion is considered to be at high risk for surgery. The transluminal aortic valve implantation technique has been increasingly used over the past few years, thus providing a solution to a major therapeutic issue in our industrialized countries. While the cardiology community was rapidly convinced of its efficacy, remaining doubts regarding the outcome of this technique in terms of mortality were erased by the recent publication of results achieved in cohort B of the Partner US trial. This new approach is clearly here to stay and should soon reach a maturity phase with respect to its indications, the selection of patients and technical aspects.

ESC Working Group on Valvular Heart Disease Position Paper: assessing the risk of interventions in patients with valvular heart disease

AIMS

Risk scores provide an important contribution to clinical decision-making, but their validity has been questioned in patients with valvular heart disease (VHD), since current scores have been mainly derived and validated in adults undergoing coronary bypass surgery. The Working Group on Valvular Heart Disease of the European Society of Cardiology reviewed the performance of currently available scores when applied to VHD, in order to guide clinical practice and future development of new scores.

METHODS AND RESULTS

The most widely used risk scores (EuroSCORE, STS, and Ambler score) were reviewed, analysing variables included and their predictive ability when applied to patients with VHD. These scores provide relatively good discrimination, i.e. a gross estimation of risk category, but cannot be used to estimate the exact operative mortality in an individual patient because of unsatisfactory calibration.

CONCLUSION

Current risk scores do not provide a reliable estimate of exact operative mortality in an individual patient with VHD. They should therefore be interpreted with caution and only used as part of an integrated approach, which incorporates other patient characteristics, the clinical context, and local outcome data. Future risk scores should include additional variables, such as cognitive and functional capacity and be prospectively validated in high-risk patients. Specific risk models should also be developed for newer interventions, such as transcatheter aortic valve implantation.

Poor performances of EuroSCORE and CARE score for prediction of perioperative mortality in octogenarians undergoing aortic valve replacement for aortic stenosis

BACKGROUND AND OBJECTIVE

Although results of cardiac surgery are improving, octogenarians have a higher procedure-related mortality and more complications with increased length of stay in ICU. Consequently, careful evaluation of perioperative risk seems necessary. The aims of our study were to assess and compare the performances of EuroSCORE and CARE score in the prediction of perioperative mortality among octogenarians undergoing aortic valve replacement for aortic stenosis and to compare these predictive performances with those obtained in younger patients.

METHODS

This retrospective study included all consecutive patients undergoing cardiac surgery in our institution between November 2005 and December 2007. For each patient, risk assessment for mortality was performed using logistic EuroSCORE, additive EuroSCORE and CARE score. The main outcome measure was early postoperative mortality. Predictive performances of these scores were assessed by calibration and discrimination using goodness-of-fit test and area under the receiver operating characteristic curve, respectively.

RESULTS

During this 2-year period, we studied 2117 patients, among whom 134/211 octogenarians and 335/1906 nonoctogenarians underwent an aortic valve replacement for aortic stenosis. When considering patients with aortic stenosis, discrimination was poor in octogenarians and the difference from nonoctogenarians was significant for each score (0.58, 0.59 and 0.56 vs. 0.82, 0.81 and 0.77 for additive EuroSCORE, logistic EuroSCORE and CARE score in octogenarians and nonoctogenarians, respectively, P < 0.05). Moreover, in the whole cohort, logistic EuroSCORE significantly overestimated mortality among octogenarians.

CONCLUSION

Predictive performances of these scores are poor in octogenarians undergoing cardiac surgery, especially aortic valve replacement. Risk assessment and therapeutic decisions in octogenarians should not be made with these scoring systems alone.

One year follow-up of the multi-centre European PARTNER transcatheter heart valve study

Background

Transcatheter aortic valve implantation (TAVI) has emerged as a new therapeutic option in high-risk patients with severe aortic stenosis.

Aims

PARTNER EU is the first study to evaluate prospectively the procedural and mid-term outcomes of transfemoral (TF) or transapical (TA) implantation of the Edwards SAPIEN® valve involving a multi-disciplinary approach.

Methods and results

Primary safety endpoints were 30 days and 6 months mortality. Primary efficacy endpoints were haemodynamic and functional improvement at 12 months. One hundred and thirty patients (61 TF, 69 TA), aged 82.1 ± 5.5 years were included. TA patients had higher logistic EuroSCORE (33.8 vs. 25.7%, P = 0.0005) and more peripheral disease (49.3 vs. 16.4%, P< 0.0001). Procedures were aborted in four TA (5.8%) and six TF cases (9.8%). Valve implantation was successful in the remaining patients in 95.4 and 96.4%, respectively. Thirty days and 6 months survival were 81.2 and 58.0% (TA) and 91.8 and 90.2% (TF). In both groups, mean aortic gradient decreased from 46.9 ± 18.1 to 10.9 ± 5.4 mmHg 6 months post-TAVI. In total, 78.1 and 84.8% of patients experienced significant improvement in New York Heart Association (NYHA) class, whereas 73.9 and 72.7% had improved Kansas City Cardiomyopathy Questionnaire (KCCQ) scores in TA and TF cohorts, respectively.

Conclusion

This first team-based multi-centre European TAVI registry shows promising results in high-risk patients treated by TF or TA delivery. Survival rates differ significantly between TF and TA groups and probably reflect the higher risk profile of the TA cohort. Optimal patient screening, approach selection, and device refinement may improve outcomes.

Performance of Four Risk Algorithms in Predicting Intermediate Survival in Patients Undergoing Aortic Valve Replacement

Objective

Several risk models exist to predict operative outcomes after cardiac surgery and are used in selecting patients for alternative procedures such as transcatheter valve implantation. We sought to evaluate the performance of the Society of Thoracic Surgeons Predicted Risk of Mortality (STS-PROM) model in accurately identifying patients at high risk for aortic valve replacement (AVR).

Methods

Three hundred and ninety four consecutive patients who underwent isolated AVR from January 1, 2001, to July 1, 2007, at a tertiary care center were analyzed using the STS database. Patients were stratified into tertiles according to operative surgical risk calculated by the four models [STS-PROM, European system for cardiac operative risk evaluation (EuroSCORE), Ambler, and Providence]. Vital status at 1 year was determined using the National Death Index and Social Security Death Index.

Results

There were 310 low-risk patients, 56 intermediate-risk patients, and 28 high-risk patients with respect to the STS-PROM. The predicted risk of death for the low-risk, intermediate-risk, and high-risk groups were 2.4% ± 1.1%, 6.9% ± 1.4%, 15.8% ± 7.6% (P < 0.001) with respect to the STS-PROM model. Actual operative mortality for each respective group was 1.94%, 5.36%, 14.29% (P < 0.001) and 1-year mortality was 3.23%, 12.50%, 21.43% (P < 0.001), respectively.

Conclusions

High-risk patients have significantly high mortality after AVR. The STS-PROM accurately predicts operative mortality and can be used to predict 1-year survival as well. This risk model may be preferentially used instead of the EuroSCORE.

[Transcatheter aortic valve implantation]

Degenerative aortic valve stenosis accounts for the majority of native valve diseases and the prognosis is poor for symptomatic patients if untreated. Owing to the progressive aging of the population, the incidence of symptomatic aortic stenoses will further increase. Surgical aortic valve replacement provides a valuable treatment option with a well-documented favorable long-term outcome. However, the risk of surgery increases especially in older patients with significant comorbidities. For this reason, one third of symptomatic patients is not considered suitable for surgery. Transcatheter off-pump aortic valve implantation, however, using a transfemoral or a transapical approach may be a suitable therapeutic option for these patients. The balloon-expandable Edwards-SAPIEN prosthesis and the self-expandable Medtronic Core- Valve system have received CE approval and more than 10,000 patients have been treated worldwide.Both methods share the same main principles: after crossing the stenotic aortic valve, balloon valvuloplasty is performed during a short episode of rapid ventricular pacing to predilate the native valve. After careful positioning of the valve prosthesis using either transesophageal echocardiography or fluoroscopy or both, the valve is released.30-day mortality ranges between 8% and 15% in different registries in higher-risk patients. Nonetheless, larger randomized trials are warranted in order to validate the safety and effectiveness of this new approach.

Thirty-day results of the SAPIEN aortic Bioprosthesis European Outcome (SOURCE) Registry: A European registry of transcatheter aortic valve implantation using the Edwards SAPIEN valve

BACKGROUND

Transcatheter aortic valve implantation was developed to mitigate the mortality and morbidity associated with high-risk traditional aortic valve replacement. The Edwards SAPIEN valve was approved for transcatheter aortic valve implantation transfemoral delivery in the European Union in November 2007 and for transapical delivery in January 2008.

METHODS AND RESULTS

The SAPIEN Aortic Bioprosthesis European Outcome (SOURCE) Registry was designed to assess the initial clinical results of the Edwards SAPIEN valve in consecutive patients in Europe after commercialization. Cohort 1 consists of 1038 patients enrolled at 32 centers. Patients who were treated with the transapical approach (n=575) suffered more comorbidities than the transfemoral patients (n=463), resulting in a significantly higher logistic EuroSCORE (29.1% versus 25.7%; P<0.001). Therefore, these groups are considered different, and outcomes cannot be compared. Overall short-term procedural success was observed in 93.8%. The incidence of valve embolization was 0.3% (n=3), and coronary obstruction was reported for 0.6% (n=6 cases). Incidence of stroke was 2.5% and similar for both procedural approaches. Thirty-day mortality was 6.3% in transfemoral patients and 10.3% in transapical patients. The occurrence of vascular complications was not a predictor of <30-day mortality in the transfemoral population.

CONCLUSIONS

Technical proficiency can be learned and adapted readily as demonstrated by the short-term procedural success rate and low 30-day mortality rates reported in the SOURCE Registry. Specific complication management and refinement of patient selection are needed to further improve outcomes.

Immediate and mid-term results of transfemoral aortic valve implantation using either the Edwards Sapien transcatheter heart valve or the Medtronic CoreValve System in high-risk patients with aortic stenosis

OBJECTIVE

We sought to describe the results of transfemoral aortic valve implantation using either the Sapien prosthesis or the CoreValve System.

BACKGROUND

Results of transfemoral aortic valve implantation using both commercially available prostheses have rarely been studied.

PATIENTS

Of 236 patients at high-risk or with contraindications to surgery, consecutively referred for transcatheter aortic valve implantation between October 2006 and June 2009, 83 were treated with transfemoral aortic valve implantation. The Sapien was the only prosthesis available until May 2008 and, since then, was used as the first option, while the CoreValve System was used when contraindications to the Sapien prosthesis were present.

RESULTS

Patients were aged 81+/-9 years, 98% in New York Heart Association classes III/IV, with predicted surgical mortalities of 26+/-14% using the EuroSCORE and 15+/-8% using the Society of Thoracic Surgeons Predicted Risk of Mortality score. Seventy-two patients were treated with the Sapien prosthesis and 11 with the CoreValve System. The valve was implanted in 94% of the cases. Thirty-day mortality was 7%. Overall, 1- and 2-year survival rates were 78+/-5% and 71+/-7%, respectively. Among patients treated with the Sapien, the 1-year survival rate was 67+/-12% in the first 20% of patients versus 86+/-5% in the last 80% of patients (p=0.02). In univariate analysis, early experience was the only significant predictor of 1-year mortality.

CONCLUSION

Combining the use of the Sapien and the CoreValve prostheses increases the number of patients who can be treated by transfemoral aortic valve implantation and provides satisfactory results at 2 years in this high-risk population. The results are strongly influenced by experience.

Percutaneous implantation of the CoreValve self-expanding aortic valve prosthesis in patients with severe aortic stenosis: early experience in Spain

INTRODUCTION AND OBJECTIVES

The aim of the study was to describe early experience and medium-term follow-up with the CoreValve self-expanding aortic prosthesis at three Spanish hospitals.

METHODS

The study included patients with severe symptomatic aortic stenosis. Other inclusion criteria were: aortic valve area <1 cm(2) (<0.6 cm(2)/m(2)); aortic valve annulus diameter in the range 20-27 mm; diameter of the ascending aorta at the level of the sinotubular junction < or = 40 mm (small prosthesis) or < or = 43 mm (large prosthesis), and femoral artery diameter >6 mm.

RESULTS

The study included 108 patients with a mean age of 78.6 + or - 6.7 years, a mean aortic valve area of 0.63 + or - 0.2 cm(2) and a mean logistic EuroSCORE of 16% + or - 13.9% (range, 2.27%-86.4%). After valve implantation, the maximum echocardiographic transaortic valve gradient decreased from 83.8 + or - 23 to 12.6 + or - 6 mmHg. No patient presented with greater than grade-2 residual aortic regurgitation on angiography. The procedural success rate was 98.1%. No patient died during the procedure. Definitive pacemaker implantation was carried out for atrioventricular block in 38 patients (35.2%). At 30 days, all-cause mortality and the rate of the combined endpoint of death, stroke, myocardial infarction or referral for surgery were 7.4% and 8.3%, respectively. The estimated 1-year survival rate calculated using the Kaplan-Meier method was 82.3% (for a median follow-up period of 7.6 months).

CONCLUSIONS

Our early experience indicates that percutaneous aortic valve replacement is a safe and practical therapeutic option for patients with severe aortic stenosis who are at a high surgical risk.

Percutaneous implantation of the CoreValve self-expanding aortic valve prosthesis in patients with severe aortic stenosis: early experience in Spain

INTRODUCTION AND OBJECTIVES

The aim of the study was to describe early experience and medium-term follow-up with the CoreValve self-expanding aortic prosthesis at three Spanish hospitals.

METHODS

The study included patients with severe symptomatic aortic stenosis. Other inclusion criteria were: aortic valve area <1 cm(2) (<0.6 cm(2)/m(2)); aortic valve annulus diameter in the range 20-27 mm; diameter of the ascending aorta at the level of the sinotubular junction < or = 40 mm (small prosthesis) or < or = 43 mm (large prosthesis), and femoral artery diameter >6 mm.

RESULTS

The study included 108 patients with a mean age of 78.6 + or - 6.7 years, a mean aortic valve area of 0.63 + or - 0.2 cm(2) and a mean logistic EuroSCORE of 16% + or - 13.9% (range, 2.27%-86.4%). After valve implantation, the maximum echocardiographic transaortic valve gradient decreased from 83.8 + or - 23 to 12.6 + or - 6 mmHg. No patient presented with greater than grade-2 residual aortic regurgitation on angiography. The procedural success rate was 98.1%. No patient died during the procedure. Definitive pacemaker implantation was carried out for atrioventricular block in 38 patients (35.2%). At 30 days, all-cause mortality and the rate of the combined endpoint of death, stroke, myocardial infarction or referral for surgery were 7.4% and 8.3%, respectively. The estimated 1-year survival rate calculated using the Kaplan-Meier method was 82.3% (for a median follow-up period of 7.6 months).

CONCLUSIONS

Our early experience indicates that percutaneous aortic valve replacement is a safe and practical therapeutic option for patients with severe aortic stenosis who are at a high surgical risk.

EuroSCORE performance in valve surgery: a meta-analysis

BACKGROUND

The European System for Cardiac Operative Risk Evaluation (EuroSCORE) was developed to predict immediate outcomes after adult cardiac operations, but less than 30% of the cases used to develop this score were valve procedures. We studied EuroSCORE performance in valve procedures.

METHODS

We performed a meta-analysis of published studies reporting the assessment of discriminatory power of the EuroSCORE by receiver operating characteristics (ROC) curve analysis in adult valve operations. A comparison of observed and predicted mortality rates was also performed.

RESULTS

A literature search identified 37 potentially eligible studies, and 12 were selected for meta-analysis comprising 26,621 patients with 1250 events (mortality rate, 4.7%). Meta-analysis of these studies provided an average area under the curve (AUC) value of 0.730 (95% confidence interval [CI], 0.717 to 0.743). The same results were obtained when meta-analyses were performed separately in studies categorized on reliability of uncertainty estimation: in the seven studies reporting reliable uncertainty estimation (8175 patients with 358 events; mortality rate, 4.4%), the ROC curve provided an average AUC value of 0.724 (95% CI, 0.699 to 0.749). The five studies not reporting reliable uncertainty estimation (18,446 patients with 892 events; mortality rate, 4.8%) had an average AUC of 0.732 (95% CI, 0.717 to 0.747). We documented a constant trend to overpredict mortality by EuroSCORE, both in the additive and especially in the logistic form.

CONCLUSIONS

The EuroSCORE has low discrimination ability for valve surgery, and it sensibly overpredicts risk. Alternative risk scoring algorithms should be seriously considered.

Clinical profile, treatment assignment and clinical outcome of patients with severe aortic stenosis not eligible to participate in a clinical trial of percutaneous aortic valve replacement

Patients with severe aortic stenosis and considered at high surgical risk or inoperable, and not eligible for a randomized clinical trial evaluating percutaneous aortic valve replacement (PAVR), were studied. Many of the patients referred to the study did not meet the inclusion criteria and/or had conditions listed in the exclusion criteria. These patients were then deferred to other treatment modalities. The study cohort consisted of 285 patients with severe aortic stenosis referred to participate in a clinical trial of PAVR. Patients were screened for eligibility on the basis of the protocol inclusion and exclusion criteria and deferred to other treatment modalities if they did not meet the enrollment criteria. Those patients were followed clinically by telephone contact or office visits. Of the 285 patients referred for PAVR, 216 (75.8%) were not included. The leading reasons for lack of eligibility were significant peripheral vascular disease in 50 (23.1%), Society of Thoracic Surgeons score <10% in 48 (22.9%), aortic valve area >0.8 cm(2) in 30 (13.9%), significant coronary artery disease in 25 (11.6%), and renal failure in 22 (10.2%). Sixty-nine of these patients (31.9%) were treated medically, 102 (47.2%) with balloon aortic valvuloplasty, and 45 (20.9%) with surgical aortic valve replacement. Major baseline characteristics were similar. Society of Thoracic Surgeons scores were lower in the surgical group compared with the medical and balloon aortic valvuloplasty groups (10.2 +/- 2.5 vs 12.8 +/- 3.3 vs 13.7 +/- 3.3, respectively, p <0.001). During a median follow-up period of 175.5 days (range 55.7 to 344.75), the mortality rate was higher in the balloon aortic valvuloplasty group compared with the medical and surgical aortic valve replacement groups (46 [45.1%] vs 22 [31.9%] vs 10 [22.2%], respectively, p = 0.01). In conclusion, high-risk patients with severe aortic stenosis who are deferred from PAVR often do poorly and incur high mortality rates, especially when treated with balloon valvuloplasty or medical therapy, while a loss of quality of life is apparent in those treated surgically.

Relationship between the logistic EuroSCORE and the Society of Thoracic Surgeons Predicted Risk of Mortality score in patients implanted with the CoreValve ReValving system--a Bern-Rotterdam Study

BACKGROUND

Surgical risk scores, such as the logistic EuroSCORE (LES) and Society of Thoracic Surgeons Predicted Risk of Mortality (STS) score, are commonly used to identify high-risk or "inoperable" patients for transcatheter aortic valve implantation (TAVI). In Europe, the LES plays an important role in selecting patients for implantation with the Medtronic CoreValve System. What is less clear, however, is the role of the STS score of these patients and the relationship between the LES and STS.

OBJECTIVE

The purpose of this study is to examine the correlation between LES and STS scores and their performance characteristics in high-risk surgical patients implanted with the Medtronic CoreValve System.

METHODS

All consecutive patients (n = 168) in whom a CoreValve bioprosthesis was implanted between November 2005 and June 2009 at 2 centers (Bern University Hospital, Bern, Switzerland, and Erasmus Medical Center, Rotterdam, The Netherlands) were included for analysis. Patient demographics were recorded in a prospective database. Logistic EuroSCORE and STS scores were calculated on a prospective and retrospective basis, respectively.

RESULTS

Observed mortality was 11.1%. The mean LES was 3 times higher than the mean STS score (LES 20.2% +/- 13.9% vs STS 6.7% +/- 5.8%). Based on the various LES and STS cutoff values used in previous and ongoing TAVI trials, 53% of patients had an LES > or =15%, 16% had an STS > or =10%, and 40% had an LES > or =20% or STS > or =10%. Pearson correlation coefficient revealed a reasonable (moderate) linear relationship between the LES and STS scores, r = 0.58, P < .001. Although the STS score outperformed the LES, both models had suboptimal discriminatory power (c-statistic, 0.49 for LES and 0.69 for STS) and calibration.

CONCLUSIONS

Clinical judgment and the Heart Team concept should play a key role in selecting patients for TAVI, whereas currently available surgical risk score algorithms should be used to guide clinical decision making.

The EuroSCORE - still helpful in patients undergoing isolated aortic valve replacement?

BACKGROUND

The European System for Cardiac Operative Risk Evaluation (EuroSCORE) is one of the most prominent scores used for the evaluation of predicted mortality in cardiac surgery. The aim of our study was to analyze the logistic and additive EuroSCORE in view of its accuracy for patients undergoing isolated aortic valve replacement (AVR).

METHODS

A total of 652 patients underwent isolated AVR from January 1999 to June 2007. Emergency and redo operations were included. Acute endocarditis was excluded. Out of logistic regression analyses, receiver operating characteristic (ROC) curve statistics were calculated both for the logistic and additive EuroSCORE.

RESULTS

By using the identical variables used in the EuroSCORE, the area under curve was 70.7% for the logistic and 72.4% for the additive EuroSCORE, respectively. If age, which is by nature positively correlated with increasing cardiac and non-cardiac comorbidity, is calculated as a single parameter, the area under curve remains at 69.9% being very close to the result of the EuroSCORE.

CONCLUSIONS

For the subgroup of patients undergoing isolated AVR, the use of the EuroSCORE provides a comparable precision concerning the estimation of early mortality compared with the simple factor 'age'. The extended use of the EuroSCORE in view of percutaneous AVR, the insufficient accuracy of the score bears the risk of incorrect decision-making.

Development of aortic valve implantation

Aortic valve stenosis is an important public-health problem in Europe and is predicted to increase with the aging population. Management of severe symptomatic aortic stenosis is by surgical replacement of the aortic valve whenever feasible. Improvement in the perioperative management has permitted surgical intervention in high-risk patients. However, patients refused surgery can now be managed by transcatheter techniques. These have opened new horizons for patients for whom conventional surgery is contraindicated or the technical complexity of the procedure is associated with considerable operative risk. The development of transcatheter aortic valve implantation, available technology, choice of approach, and future perspectives are discussed.

New antimicrobial activity for the catecholamine release-inhibitory peptide from chromogranin A

Catestatin (bCGA(344-364)), an endogenous peptide of bovine chromogranin A, was initially characterized for its effect on the inhibition of catecholamine release from chromaffin cells. Catestatin and its active domain (bCGA(344-358)) were identified in chromaffin cells and in secretion medium. The present study identified a potent antimicrobial activity of bCGA(344-358) in the lowmicromolar range against bacteria, fungi and yeasts, without showing any haemolytic activity. Confocal laser microscopy demonstrated penetration of the rhodaminated peptide into the cell membranes of fungi and yeasts and its intracellular accumulation. Time-lapse videomicroscopy showed arrest of fungal growth upon penetration of the labelled peptide into a fungal filament. We identified several catestatin-containing fragments in the stimulated secretion medium of human polymorphonuclear neutrophils, suggesting the N-terminal sequence of catestatin (bCGA(344-358)) (named cateslytin) as a novel component of innate immunity.