An Updated Comprehensive Review of Existing Transcatheter Aortic Valve Replacement Access

For the past 20 years, transcatheter aortic valve replacement (TAVR) has been the treatment of choice for symptomatic aortic stenosis. The transfemoral (TF) access is considered the gold standard approach for TAVR. However, TF-TAVR cannot be performed in some patients; thus, alternative accesses are required. Our review paper generalises the TAVR accesses currently available, including the transapical, transaortic, trans-subclavian/axillary, transcarotid, transcaval, and suprasternal approaches. Their advantages and disadvantages have been analysed. Since there is no standard recommendation for an alternative approach, access selection depends on the expertise of the local cardiac team, patient characteristics, and access properties. Each TAVR centre is recommended to master a minimum of one non-TF access alternative. Of note, more evidence is required to delve into the clinical outcomes of each approach, at both early and long-term (Figure 1).

Alternative access in high-risk patients in the era of transfemoral aortic valve replacement

BACKGROUND

We aimed to evaluate the outcomes of transapical and transaortic transcatheter aortic valve replacement (TAVR) in high-risk patients who were not suitable for transfemoral access and had a logistic EuroSCORE-I ≥ 25% and Society of Thoracic Surgeons (STS) score >6%. 'STS/ACC TAVR In-Hospital Mortality Risk App' was evaluated.

MATERIAL AND METHODS

Between January 2016 and May 2020, 126 patients at very high risk for aortic valve replacement underwent transapical (n = 121) or transaortic (n = 5) transcatheter aortic valve replacement. TAVR was performed using SAPIEN 3™ or ACURATE TA™ prosthesis.

RESULTS

The logistic EuroSCORE-I was 40.6 ± 14.0%, the STS-score 7.9 ± 4.6%, and STS/ACC-score 8.4 ± 3.4%. Valve implantation was successful in all patients. Operative, in-hospital and 30-days mortality, were 0, 7.9, and 13.5%, respectively. Survival was 72% at one year and 48% at four years. Expected/observed in-hospital mortality was 1.0 for the STS-score and 1.06 for the STS/ACC-score. Renal failure, low ejection fraction, and postoperative acute kidney injury, hemorrhage, and vascular complications were identified as independent predictors for 30-day mortality.

CONCLUSIONS

Transapical and transaortic TAVR in high-risk patients unsuitable for transfemoral access is still a reasonable alternative in these patients. STS and STS/ACC-score appear to be highly accurate in predicting in-hospital mortality in high-risk patients undergoing TAVR.

A hybrid approach for a case with a high risk of not only surgical but transcatheter aortic valve replacement

An 86-year-old woman with severe aortic stenosis was thought to be at a high risk for surgical aortic valve replacement and inoperability due to old age and porcelain aorta. Furthermore, transcatheter aortic valve replacement (TAVR) was considered difficult due to high risk of coronary obstruction secondary to the aortic root anatomy and poor vascular access associated with marked atherosclerotic lesions on the distal aortic arch with peripheral artery disease. We successfully treated her with TAVR via the brachiocephalic artery in combination with prophylactic off-pump coronary artery bypass grafting.

Current Trends in TAVI Access

The optimal approach for Transcatheter aortic valve implantation (TAVI) is the transfemoral access but alternative TAVI approaches offer the possibility of valve replacement in patients who are not eligible to the transfemoral route. This review paper intends to compare the current available alternative approaches for TAVI in terms of their safety and efficacy, based on the current literature. The transapical, transaortic, transsubclavian, transcarotid, transcaval and suprasternal approaches have been analyzed. The choice of the alternative approach dependents on local Heart Team expertise, patient specific characteristics, access specific characteristics and the need or not for general anesthesia. More studies are needed to investigate the impact of each individual approach on long-term outcomes.

Direct aortic route versus transaxillary route for transcatheter aortic valve replacement: a systematic review and meta-analysis

Background

The transfemoral route is contraindicated in nearly 10% of transcatheter aortic valve replacement (TAVR) candidates because of unsuitable iliofemoral vessels. Transaxillary (TAx) and direct aortic (DAo) routes are the principal nonfemoral TAVR routes; however, few studies have compared their outcomes.

Methods

We performed a systematic review and meta-analysis to compare the rates of mortality, stroke, and other adverse events of TAx and DAo TAVR. The study was prospectively registered with PROSPERO (registration number: CRD42017069788). We searched Medline, PubMed, Embase, and Cochrane databases for studies reporting the outcomes of DAo or TAx TAVR in at least 10 patients. Studies that did not use the Valve Academic Research Consortium definitions were excluded. We included studies that did not directly compare the two approaches and then pooled rates of events from the included studies for comparison.

Results

In total, 31 studies were included in the quantitative meta-analysis, with 2,883 and 2,172 patients in the DAo and TAx TAVR groups, respectively. Compared with TAx TAVR, DAo TAVR had a lower Society of Thoracic Surgery (STS) score, shorter fluoroscopic time, and less contrast volume use. The 30-day mortality rates were significantly higher in the DAo TAVR group (9.6%, 95% confidence interval (CI) = [8.4–10.9]) than in the TAx TAVR group (5.7%, 95% CI = [4.8–6.8]; P for heterogeneity <0.001). DAo TAVR was associated with a significantly lower risk of stroke in the overall study population (2.6% vs. 5.8%, P for heterogeneity <0.001) and in the subgroup of studies with a mean STS score of ≥8 (1.6% vs. 6.2%, P for heterogeneity = 0.005). DAo TAVR was also associated with lower risks of permanent pacemaker implantation (12.3% vs. 20.1%, P for heterogeneity = 0.009) and valve malposition (2.0% vs. 10.2%, P for heterogeneity = 0.023) than was TAx TAVR.

Conclusions

DAo TAVR increased 30-day mortality rate compared with TAx TAVR; by contrast, TAx TAVR increased postoperative stroke, permanent pacemaker implantation, and valve malposition risks compared with DAo TAVR.