May 24, 2022

Study Evaluates Transcaval and Transaxillary Artery Access for TAVR

May 24, 2022—In a study evaluating access options in transcatheter aortic valve replacement (TAVR) published in JACC: Cardiovascular Interventions, Lederman et al found lower rates of stroke in patients who underwent transcaval TAVR, better convalescence, and similar rates of bleeding and vascular complication between transcaval and transaxillary TAVR groups. The results suggest that transcaval access may be an attractive option when transfemoral access is not possible.

KEY FINDINGS

As compared with transfemoral access, transcaval and transaxillary access were associated with worse outcomes, including worse bleeding, vascular complications, stroke or TIA, ICU and hospital length of stay, and 30-day and 1-year mortality.
However, stroke or TIA was significantly less common after transcaval access as compared with transaxillary access.
Significantly more patients were discharged directly to home after transcaval access as compared with transaxillary access.
Compared with transcaval or transfemoral access, the patient-oriented composite of survival to discharge to home without stroke or TIA was significantly higher after transcaval access.

Investigators used outcome data from eight experienced centers, and individual site data for all patients who had undergone TAVR at these centers were aggregated for central analysis. For the purposes of this analysis, both subclavian and axillary access were combined as “transaxillary.”

The primary outcome measures were bleeding complications and stroke. The analysis also evaluated a post hoc patient-oriented endpoint of survival to discharge, discharge directly to home, and without stroke/transient ischemic attack (TIA).

Data were available from 7,539 patients who had undergone TAVR during the 4-year study period. Of these, 407 patients underwent nonfemoral TAVR (5.4% of all procedures); 63 were transcarotid or transthoracic and were excluded, leaving 238 transcaval and 106 transaxillary TAVR procedures for analysis.

Patients who underwent transcaval or transaxillary access tended to be at higher risk than those who underwent transfemoral access; however, the risk profile was similar between transcaval and transaxillary groups.

As expected, patients who underwent nonfemoral access had worse outcomes than those who underwent transfemoral access, including worse bleeding, vascular complications, stroke or TIA, intensive care unit (ICU) or hospital length of stay, and 30-day and 1-year (follow-up, 356 days [median first quartile, 38 days; median third quartile, 379 days]) mortality.

Stroke or TIA were significantly less common after transcaval as compared with transaxillary access before and after propensity weighting (2.5% vs 13.2%; odds ratio [OR], 0.20; 95% CI, 0.06-0.72; P = .014). Bleeding and vascular complications were comparable between transcaval and transaxillary groups, with hemoglobin drop slightly more common in the transcaval group.

Significantly more patients were discharged directly to home (vs to a nursing facility or hospice) after transcaval access as compared with transaxillary access (92.6% vs 69.6%; OR, 6.1; 95% CI, 2.4-15; P < .0001). The patient-oriented composite of survival to discharge to home without stroke or TIA was significantly lower after transaxillary access as compared with transcaval (87.8% vs 62.3%; OR, 5.2; 95% CI, 2.4-11; P < .0001) and transfemoral access (90.3%).

The authors reported that the study limitations included the nonrandom allocation to type of access, the potential for referral bias of more risky cases to more experienced operators, and the potential for unmeasured confounding despite adjustment of baseline imbalances.

Despite these limitations, the investigators concluded that bleeding complications or vascular complications do not appear to be worse with transcaval access, and by some measures, it appears superior to transaxillary access.

CARDIAC INTERVENTIONS TODAY ASKS…

Lead investigator Robert J. Lederman, MD, with the National Heart, Lung, and Blood Institute of the National Institutes of Health in Bethesda, Maryland, was asked to elaborate on this study’s findings.

Based on the study results, you concluded that transcaval TAVR may prove the percutaneous nonfemoral access of choice, but more real-world experience is required. What would a future study look like to corroborate this finding?

A randomized trial between transcaval and transaxillary access approaches would address lingering concerns. However, many physicians find the stroke incidence sufficiently worrisome that we may no longer have equipoise to randomize to transaxillary when there are alternatives. More interesting might be a comparison of transcaval with transcarotid access among patients who are ineligible for standard transfemoral access. Although transcaval access is fully percutaneous, transcarotid access generally requires surgical cutdown, and both have different resource requirements including anesthesia, ICU stay, and equipment costs.

How do the findings affect your real-world consideration of when to use transcaval access for TAVR?

We have shown that physicians can achieve proficiency in transcaval access techniques after a small number of cases, so I would have thought transcaval techniques would be more widely adopted already.

What is known about patient preference for these two nonfemoral access options?

We were surprised to see that convalescence after transaxillary access was more protracted than after transcaval access. This is a serious issue. Most elderly patients’ priorities are to get better, avoid a stroke, and go straight home. In our retrospective study, there was a big difference in our patient-oriented composite of discharge directly home without stroke or death: 88% after transcaval versus 62% after transaxillary. Given our findings, I think most patients would choose transcaval over transaxillary access.

What are the main learning curve hurdles for mastering transcaval access, including when to select it?

Transcaval access and closure is easy to learn, and industry or peer proctorship is available. Dedicated commercial devices, which appear to be easier to use, have been successful in early human tests but await industry investment.¹* Eligibility is mostly determined by CT scan. Candidates need a calcium-free window on the caval side of the aorta, away from important arterial branches, with no interposed viscerae, within reach of an available TAVR introducer sheath. Caval-aortic distance does not matter. Most patients who are ineligible for standard transfemoral access are eligible for transcaval access.

*Dr. Lederman is a co-inventor on patents on these devices, which are assigned to his employer (National Institutes of Health) and have been licensed and developed by Transmural Systems.

1. Rogers T, Greenbaum AB, Babaliaros VC, et al. Dedicated closure device for transcaval access closure: from concept to first-in-human testing. JACC Cardiovasc Interv. 2019;12:2198. doi: 10.1016/j.jcin.2019.05.053

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