Comparison of late mortality after transcatheter aortic valve implantation versus surgical aortic valve replacement: Insights from a meta-analysis

Myocardial protection in cardiac surgery-hindsight from the 2020s

Myocardial protection and specifically cardioplegia have been extensively investigated in the beginnings of cardiac surgery. After cardiopulmonary bypass had become routine, more and more cardiac operations were possible, requiring reliable and reproducible protection for times of blood flow interruptions to the most energy-demanding organ of the body. The concepts of hypothermia and cardioplegia evolved as tools to extend cardiac ischaemia tolerance to a degree considered safe for the required operation. A plethora of different solutions and delivery techniques were developed achieving remarkable outcomes with cross-clamp times of up to 120 min and more. With the beginning of the new millennium, interest in myocardial protection research declined and, as a consequence, conventional cardiac surgery is currently performed using myocardial protection strategies that have not changed in decades. However, the context, in which cardiac surgery is currently performed, has changed during this time. Patients are now older and suffer from more comorbidities and, thus, other organs move more and more into the centre of risk assessment. Yet, systemic effects of cardioplegic solutions have never been in the focus of attention. They say hindsight is always 20-20. We therefore review the biochemical principles of ischaemia, reperfusion and cardioplegic extension of ischaemia tolerance and address the concepts of myocardial protection with 'hindsight from the 2020s'. In light of rising patient risk profiles, minimizing surgical trauma and improving perioperative morbidity management becomes key today. For cardioplegia, this means accounting not only for cardiac, but also for systemic effects of cardioplegic solutions.

Risk Factors of Midterm Mortality After Aortic Valve Replacement for Severe Calcified Tricuspid Aortic Valve Stenosis: A retrospective analysis of Perioperative Events Assessment in Adult Cardiac surgery (PESSAC) Registry

OBJECTIVE

The European System for Cardiac Operative Risk Evaluation II (EuroSCORE II) initially developed for predicting early postoperative mortality of all types of cardiac surgery, is less able to predict, more specifically, long-term outcomes after aortic valve replacement (AVR). The study authors here evaluated the risk factors for three-year mortality after isolated aortic valve replacement (AVR) for severe calcified tricuspid aortic valve stenosis and compared them with EuroSCORE II to predict long-term outcomes.

DESIGN

A retrospective study.

SETTING

A university teaching hospital.

PARTICIPANTS

This study included 1,101 adults who underwent isolated AVR for severe calcified tricuspid aortic valve stenosis between September 2010 to June 2015.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

The primary endpoint was that of three-year all-cause mortality after AVR. By three years, 168 patients (15.3%) had died. Risk factors for all-cause mortality were: male gender (odds ratio [OR] = 1.78; 95% confidence interval [CI] = 1.21-2.62; p < 0.01), peripheral arterial disease (OR = 1.77; 95% CI = 1.08-2.92; p = 0.03), age (OR = 1.06 per year increase; 95% CI =1.04-1.09; p < 0.01), pulmonary artery systolic pressure (OR = 1.02 per mmHg increase; 95% CI = 1.01-1.03; p < 0.01), platelet count (OR = 1.003 per G/L increase; 95% CI = 1.000-1.005; p = 0.04), and valve area (OR = 0.97 per cm²/m² increase; 95% CI= 0.95-0.99; p < 0.01). The area under the receiver operating characteristic curves were 0.67 (95% CI = 0.60-0.75) and 0.60 (95% CI = 0.56-0.65) for the authors' logistic regression model and EuroSCORE II, respectively (p = 0.11).

CONCLUSIONS

The study authors identified six independent risk factors for three-year mortality after isolated AVR. The logistic regression model had relatively modest predictive performance for three-year mortality.

Red blood cell distribution width in patients undergoing transcatheter aortic valve implantation: Implications for outcomes

BACKGROUND

Red cell distribution width (RDW) is recently emerging as a prognostic indicator in many cardiovascular diseases. However, less is known about its predictive role in patients undergoing transcatheter aortic valve implantation (TAVI).

METHODS

We retrospectively included very high-risk patients with severe aortic valve stenosis undergoing TAVI between February 2012 and December 2019. Patients were classified according to RDW tertiles. Our primary endpoint was long-term all-cause mortality. The secondary endpoint was a composite of in-hospital major adverse events as defined by the Valve Academic Research Consortium 2 criteria and/or long-term all-cause mortality.

RESULTS

A total of 424 patients [median age 83.5 years, 52.6% females] were analysed. After a median follow-up of 1.55 years, all-cause mortality was 25.5%. At the multivariate-adjusted Cox regression analysis, patients in the highest RDW tertile were associated with a higher risk for all-cause mortality [hazard ratio [HR] 1.73, 95%confidence interval [CI] 1.02-2.95] compared with the lowest tertile. When considering RDW as a continuous variable, we found an 11% increased risk in overall mortality [HR 1.11, 95% CI 1.00-1.24] for each increased point in RDW. The highest RDW tertile was also independently associated with the occurrence of the composite endpoint [odds ratio [OR] 2.10, 95% CI 1.17-3.76] compared with lower tertiles.

CONCLUSIONS

In our cohort, elevated basal RDW values were independent predictors of increased long-term mortality and higher rate of in-hospital adverse events. The inclusion of a routinely available biomarker as RDW, may help the pre-operative risk assessment in potential TAVI candidates and optimise their management.

Kidney dysfunction and short term all-cause mortality after transcatheter aortic valve implantation

BACKGROUND

Acute kidney injury (AKI) after transcatheter aortic valve implantation (TAVI) has been associated with worse outcomes. However, the impact on outcome of AKI in TAVI-patients is not well established.

METHODS

Inoperable patients with severe aortic stenosis (AS) undergoing TAVI in 2010-2018 were enrolled in this study. AKI and chronic kidney disease (CKD) were defined according to KDIGO guidelines. Patients were divided in two groups according to post-procedural AKI development. The primary endpoint was 30-day all-cause mortality across the two groups.

RESULTS

A total of 373 patients (mean age 82.3 ± 6) were analyzed. Compared to non-AKI patients, those who developed AKI, were treated more frequently with trans-apical TAVI (66% vs 35%, p<0.01), with greater amount of contrast medium (200.6 vs 170.4 ml, p=0.02) and in presence of clinically significant peripheral artery disease (PAD, 33% vs 21%, p=0.04). Trans-apical access (OR 3.24, 95% CI 1.76-5.60, p<0.01) was associated with a 3-fold risk of AKI. After adjustment for age, Society of Thoracic Surgery risk score (STS), PAD, access type, EF and contrast medium amount, patients with AKI presented an increased risk of 30-day all-cause mortality (HR=1.25, 95%CI 1.09-1.69, p=0.008). Patients with CKD IV and V, who developed AKI, presented a 9-fold 30-day mortality risk (HR=9.71, 95% CI 2.40-39.2, p=0.001).

CONCLUSION

In our analysis, AKI was a strong predictor of 30-day all-cause mortality. Particularly, patients with severe CKD with AKI showed the highest 30-day mortality risk. Thus, this group of patients might benefit from closer monitoring and specific kidney protection therapies.

High-dimensional propensity scores improved the control of indication bias in surgical comparative effectiveness studies

OBJECTIVES

The objective of the study is to evaluate the performance of high-dimensional propensity scores (hdPSs) for controlling indication bias as compared with propensity scores (PSs) in surgical comparative effectiveness studies.

STUDY DESIGN AND SETTING

Patients who underwent interventional transcatheter aortic valve implantation (TAVI) or surgical aortic valve replacement (SAVR) between 2013 and 2017 were included from the French nationwide hospitals. At each hospital level, matched pairs of patients who underwent TAVI and SAVR were formed using PSs, considering 20 patient baseline characteristics, and hdPSs, considering the same patient characteristics and 300 additional variables from procedure and diagnosis codes the year before surgery. We compared death, reoperation, and stroke up to 3 years between TAVI and SAVR using Cox or Fine and Gray models.

RESULTS

Before matching, 12 of 20 patient characteristics were imbalanced between the included patients who underwent TAVI and SAVR. No significant imbalance persisted after matching with both methods. Hazard ratio of 1-year death, reoperation, and stroke was 1.3 [1.1; 1.4], 1.6 [1.1; 2.4], and 1.4 [1.2; 1.7] for TAVI relative to SAVR with PSs (n = 9,498 pairs) and 1.1 [1.0; 1.3], 1.3 [0.8; 2.0], and 1.3 [1.0; 1.6] with hdPSs (n = 7,157).

CONCLUSION

HdPS estimations were more consistent with results seen in randomized controlled trials. The HdPS is a promising alternative for the PS to control indication bias in comparative studies of surgical procedures.

Comparison of transcatheter versus surgical aortic valve implantation in high-risk patients: A nationwide study in France

OBJECTIVE

To compare the clinical outcomes and direct costs at 5 years between transcatheter aortic valve implantation (TAVI) and surgical aortic valve replacement (SAVR) using real-world evidence.

METHODS

We performed a nationwide longitudinal study using data from the French Hospital Information System from 2009 to 2015. We matched, inside hospitals, 2 cohorts of adults who underwent TAVI or SAVR during 2010 on propensity score based on patient characteristics. Outcomes analysis included mortality, morbidity, and total costs and with a maximum 60-month follow-up. Clinical outcomes were compared between cohorts using hazard ratios (HRs) estimated from a Cox proportional hazards model for all-cause death, and from Fine and Gray's competing risk model for morbidity.

RESULTS

Based on a cohort of 1598 patients (799 in each group) from 27 centers, a higher risk of death was observed after 1 year with TAVI compared with SAVR (16.8% vs 12.8%, respectively; HR, 1.33; 95% confidence interval [CI], 1.02-1.72) and was sustained up to 5 years (52.4% vs 37.2%; HR, 1.56; 95% CI, 1.33-1.84). At 5 years, the risk of stroke was increased (HR, 1.64; 95% CI, 1.07-2.54) as was myocardial infarction (HR, 2.30; 95% CI, 1.12-4.69) and pacemaker implantation (HR, 2.40; 95% CI, 1.81-3.17) after TAVI. The hospitalization costs per patient at 5 years were €69,083 after TAVI and €55,687 after SAVR (P < .001).

CONCLUSIONS

In our study, high-risk patients harbored a greater risk of mortality and morbidity at 5 years after TAVI compared with those who underwent SAVR and higher hospitalizations costs. Those results should encourage caution before expanding the indications of TAVI.