Transcatheter Aortic Valve Implantation in Intermediate Surgical Risk Patients With Severe Aortic Stenosis: A Systematic Review and Meta-Analysis

Managing the patient undergoing transcatheter aortic valve replacement with ongoing mitral regurgitation

INTRODUCTION

Significant mitral regurgitation (MR) frequently coexists in patients with severe symptomatic aortic stenosis undergoing transcatheter aortic valve replacement (TAVR). These patients have worse clinical outcomes than those with non-significant MR, especially if MR persists after treatment of the aortic stenosis. The optimal treatment approach for this challenging high-risk population is not well defined.

AREAS COVERED

This review aims to present the current literature on concomitant significant MR in the TAVR population, and to provide a comprehensive algorithmic approach for clinical decision-making in this challenging cohort of patients.

EXPERT OPINION

Concomitant mitral and aortic valve disease is a complex clinical entity. An exhaustive and comprehensive assessment of patient's clinical characteristics and mitral valve anatomy and function is required in order to assess the surgical risk, predict the MR response after AVR and evaluate the feasibility of percutaneous MV treatment if necessary. Further developments in transcatheter techniques will expand the indications for double valve treatment in operable and inoperable patients with concomitant significant MR and aortic stenosis.

Transcatheter vs surgical aortic valve replacement in low to intermediate surgical risk aortic stenosis patients: A systematic review and meta-analysis of randomized controlled trials

Background

Transcatheter aortic valve replacement (TAVR) is regarded as the most superior alternative treatment approach for patients with aortic stenosis (AS) who are associated with high surgical risk, whereas the effectiveness of TAVR vs surgical aortic valve replacement (SAVR) in low to intermediate surgical risk patients remained inconclusive. This study aimed to determine the best treatment strategies for AS with low to intermediate surgical risk based on published randomized controlled trials (RCTs).

Hypothesis and Methods

RCTs that compared TAVR vs SAVR in AS patients with low to intermediate surgical risk were identified by PubMed, EmBase, and the Cochrane library from inception till April 2019. The pooled relative risks (RRs) with 95% confidence intervals (CIs) were calculated for the data collected using random‐effects models.

Results

Seven RCTs with a total of 6929 AS patients were enrolled. We noted that TAVR significantly increased the risk of transient ischemic attack (TIA) (RR: 1.43; 95%CI: 1.04‐1.96; P = .029), and permanent pacemaker implantation (RR: 3.00; 95%CI: 1.70‐5.30; P < .001). However, TAVR was associated with lower risk of post‐procedural bleeding (RR: 0.57; 95%CI: 0.33‐0.98; P = .042), new‐onset or worsening of atrial fibrillation (RR: 0.32; 95%CI: 0.23‐0.45; P < .001), acute kidney injury (RR: 0.40; 95%CI: 0.25‐0.63; P < .001), and cardiogenic shock (RR: 0.34; 95%CI: 0.19‐0.59; P < .001). The risk of aortic‐valve reintervention at 1‐ (RR: 2.63; 95%CI: 1.34‐5.15; P = .005), and 2 years (RR: 3.19; 95%CI: 1.63‐6.24; P = .001) in low to intermediate surgical risk patients who received TAVR was significantly increased than those who received SAVR.

Conclusions

These findings indicated that low to intermediate surgical risk patients who received TAVR had low risk of complications, whereas the risk of TIA, permanent pacemaker implantation, and aortic‐valve reintervention was increased.

Emergency treatment of acute decompensated critical aortic stenosis with transcatheter aortic valve implantation

Transcatheter aortic valve implantation (TAVI) is relatively contraindicated in the bicuspid aortic valve, and to our knowledge has not been tried where the true native annulus is of a size far in excess of current device capabilities. We present here a case of a successful emergency TAVI of a 73-year-old previously healthy man, who presented with cardiogenic shock, ventricular tachycardia storm and severe left ventricular dysfunction because of the underlying critical bicuspid aortic stenosis with aortic annulus area of 991.9 mm² and associated moderate aortic incompetence (the Society of Thoracic Surgeons (STS) risk score; score mortality of 40.9%). Despite the critical condition of the patient and technically challenging anatomy, successful TAVI was performed and the patient remains well with near-normal left ventricle (LV) function at 6 months follow-up.

Mortality after transcatheter versus surgical aortic valve replacement: an updated meta-analysis of randomised trials

Background

To determine whether transcatheter aortic valve implantation (TAVI) improves early (30-day) and midterm (1-year) mortality compared with surgical aortic valve replacement (SAVR), we performed an updated meta-analysis of all the currently available randomised controlled trials (RCTs).

Methods

To identify all RCTs providing both 30-day and 1‑year mortality after TAVI versus SAVR, PubMed and ClinicalTrials.gov were searched up to and including July 2019. A risk difference (RD) and its 95% confidence interval were generated using data of prespecified outcomes in both the TAVI and SAVR groups. Study-specific estimates were pooled using inverse variance-weighted averages of RDs in the random-effects model.

Results

We identified seven eligible high-quality RCTs including a total of 7631 as-treated patients. Pooled analyses demonstrated significantly lower 30-day (RD −0.60%; p = 0.046) and 1‑year all-cause mortality (RD −1.12%; p = 0.03) after TAVI than after SAVR. No funnel plot asymmetry was detected for 30-day and 1‑year mortality. Meta-regression analyses indicated that RDs of 30-day and 1‑year mortality between TAVI and SAVR were not modulated by mean Society of Thoracic Surgeons Predicted Risk of Mortality score. Bleeding complications at 30 days and 1 year and stage 2/3 acute kidney injury at 30 days were significantly less frequent after TAVI than after SAVR, whereas major vascular complications and new permanent pacemaker implantation at 30 days and 1 year were significantly more frequent after TAVI than after SAVR.

Conclusion

The best evidence from the present meta-analysis of all the currently available RCTs suggests that TAVI may reduce 30-day and 1‑year all-cause mortality compared with SAVR.

Electronic supplementary material

The online version of this article (10.1007/s12471-020-01378-1) contains supplementary material, which is available to authorized users.

Role of comprehensive geriatric assessment in low surgical risk older patients with aortic stenosis

BACKGROUND

Among elderly with severe aortic stenosis (AS), Comprehensive Geriatric Assessment (CGA) originally contributed to address to transcatheter aortic valve implantation (TAVI) patients not suitable to surgical aortic valve replacement(SAVR). Nevertheless, TAVI has recently been proposed also in lower surgical risk patients.

AIMS

To evaluate predictors of TAVI procedure and clinical outcomes among these patients.

METHODS

For each patient ≥ 65 years with severe AS referring to our Cardiac Surgery Division, CGA was performed, including functional and cognitive status, comorbidity burden, frailty, nutritional status, gait speed, hand-grip strength and number of medications. Surgical risk was evaluated according to the Society of Thoracic Surgeons (STS) score (low-risk < 4%). Post-procedural outcomes (30-day survival and post-procedural complications) were obtained by medical records and a one-year follow-up assessed survival, and functional and cognitive performance.

RESULTS

Among 154 subjects (mean age 82.9 years), 52 were at low-risk according to STS score. 32 patients were addressed to TAVI, 20 to SAVR. Variables significantly associated with TAVI-approach were lower gait speed (p 0.030) and higher number of medications (p 0.015). Short and long-term outcomes did not differ between groups.

DISCUSSION

Among CGA variables, gait speed and number of medications were associated with the decision to perform TAVI instead of SAVR, even in patients at low surgical risk. 30-day and one-year survival and one-year functional and cognitive decline were similar between groups, despite a relevant prevalence of frailty in the TAVI group.

CONCLUSIONS

We suggest that gait speed and number of medications should be considered in selecting appropriate candidates to TAVI among low surgical risk patients.

Recent Developments in Catheter-Based Cardiac Procedures

New developments in transcatheter valve technologies including aortic valve replacement and mitral valve and tricuspid valve interventions are described. Recent studies evaluating the success rate, patient outcomes, and anesthesiologic management of the procedures are discussed.

Transcatheter Aortic Valve Replacement Is Associated with Less Oxidative Stress and Faster Recovery of Antioxidant Capacity than Surgical Aortic Valve Replacement

The objective of this study was to compare oxidative stress indices in 24 patients (mean ± SD age 71 ± 13 years) undergoing surgical aortic valve replacement (SAVR) versus transcatheter aortic valve replacement (TAVR). Serum total antioxidant capacity (TAC), copper/zinc ratio (Cu/Zn), activity of lactate dehydrogenase (LDH), and thiobarbituric acid reactive substances (TBARS) were assessed at four different time-points: pre-procedure, immediately post-procedure, and one day and two days after the procedure. All oxidative stress parameters were comparable in both groups pre-procedure. TAC decreased significantly when assessed immediately after procedures in both groups (p < 0.001); however, the magnitude of the reduction was more pronounced after SAVR (88% decrease from baseline: 1.8 ± 0.1 vs. 0.2 ± 0.03 mM) compared to TAVR procedures (53% decrease from baseline: 1.9 ± 0.1 vs. 1.0 ± 0.1 mM; p < 0.001). TAC returned to baseline two days after TAVR in all patients, but was still reduced by 55% two days after SAVR. In concordance, TBARS levels and Cu/Zn ratio increased significantly with maximum levels immediately after procedures in both groups (p < 0.001), but the magnitude of the increase was significantly higher in SAVR compared to TAVR (TBARS: 3.93 ± 0.61 µM vs. 1.25 ± 0.30 µM, p = 0.015; Cu/Zn ratio: 2.33 ± 0.11 vs. 1.80 ± 0.12; p < 0.001). Two days after the procedure, TBARS levels and the Cu/Zn ratio returned to baseline after TAVR, with no full recovery after SAVR. TAVR is associated with a lesser redox imbalance and faster recovery of antioxidant capacity compared to SAVR.

Percutaneous cardiological intervention and cardiac surgery: patient-centered care. Position statement of the Spanish Society of Cardiology

The percutaneous treatment of coronary artery disease and some structural cardiovascular diseases has undergone spectacular changes. More and more patients with different types of heart disease are being treated by percutaneous or transcatheter interventions, with no such increase in patients undergoing cardiac surgery. This situation has led to different types of approach, requiring an objective analysis that includes all the factors possibly influencing these changes. This document assesses the 2 scenarios where this problem is most evident: coronary revascularization and the treatment of aortic stenosis. The document analyzes the situation of coronary revascularization in Spain, and the causes that may explain the differences between the number of patients who currently undergo percutaneous revascularization and those who undergo coronary surgery. In contrast, treatment of aortic stenosis through transcatheter aortic valve implantation will lead to a foreseeable reduction in the number of candidates for surgical replacement. Several international scientific societies have published the requirements on training and experience and the necessary operator and center volumes to implement a transcatheter aortic valve implantation program, conditions that the Spanish Society of Cardiology, adopting a patient-centered approach, considers absolutely essential. Given that the 2 forms of intervention (percutaneous and surgical) are complementary, multidisciplinary patient assessment (Heart Team) remains crucial to offer the best treatment option. In this scenario of diverse approaches, a key figure is the clinical cardiologist. Finally, the changes currently occurring in the treatment of structural heart disease will, in future, lead to the performance of procedures requiring the participation of professionals from both specialties. This approach will require a redesign of current training programs.