ABSTRACT & COMMENTARY
Is Less More? Transfemoral TAVR: The Minimalist Approach
By Jeffrey Zimmet, MD, PhD
Associate Professor of Medicine, University of California, San Francisco, Director, Cardiac Catheterization Laboratory, San Francisco VA Medical Center
Dr. Zimmet reports no financial relationships relevant to this field of study.
Babaliaros V, et al. Comparison of transfemoral transcatheter aortic valve replacement performed in the catheterization laboratory (minimalist approach) versus hybrid operating room (standard approach): Outcomes and cost analysis. JACC Cardiovasc Interv 2014; Jul 22. [Epub ahead of print].
Since its initial FDA approval in November 2011, transcatheter aortic valve replacement (TAVR) has rapidly gained acceptance as a standard therapy in the United States. The adoption of this procedure has by necessity fostered enhanced cooperation among cardiologists, cardiac surgeons, and cardiac anesthesiologists in the management of complex valve patients. This "Heart Team" approach has for the most part spilled over into the procedures themselves, which are performed in many cases in a hybrid operating room environment. In such a standard approach, the patient is managed with endotracheal intubation and general anesthesia, with concomitant use of invasive devices including pulmonary artery catheters, transesophageal echo, and Foley catheters. In the original PARTNER trial that led to U.S. approval of the Edwards Sapien valve, procedure time for transfemoral valve placement averaged 244 minutes, and patients coming out of general anesthesia spent a mean of just over 3 days in the ICU, with total hospital length of stay averaging more than 10 days.
As experience with this technique has increased, some centers have begun to perform transfemoral TAVR via a fully percutaneous technique using only moderate sedation without endotracheal intubation or TEE. It has been reported that 40% of TAVR procedures in Europe are currently performed in this manner. The authors of the current study, from the Emory University School of Medicine in Atlanta, sought to compare the outcomes and costs of such a minimalist approach (MA) TAVR to those of so-called standard approach (SA) procedures performed at their center. This was not a randomized trial — the Emory group made the transition in transfemoral procedures from SA-TAVR to MA-TAVR and sought to describe the results. During the time period from November 2010 to September 2013, MA-TAVR was performed in 70 patients and SA-TAVR in 72 patients.
Patients in the two groups were similar in baseline characteristics and estimated risk, with mean ages in the low 80s, STS scores of approximately 11%, and > 87% of patients in NYHA functional class III or IV. All patients in the MA group underwent successful procedures, while there were three procedural deaths in the SA group. There was no in-hospital mortality with the MA group, whereas there was 4.2% mortality among the SA patients. Procedural time (93 ± 32 min vs 125 ± 46 min, P < 0.001) and in-room time (150 ± 48 min vs 218 ± 56 min, P < 0.001) were significantly shorter in the MA group. Rates of moderate or severe paravalvular leak were low and were not significantly different between the two groups. Both ICU and total hospital length of stay were reduced in the MA group. After the switch over to the MA approach, the majority of patients spent no time in intensive care at all, but were transferred from the procedure directly to a telemetry floor. Subsequent to the change to the MA technique, only eight transfemoral TAVR patients underwent procedures by the SA approach, and the majority of these were done in this manner due to scheduling issues. Only three potential transfemoral patients who underwent SA TAVR during this period were managed this way due to medical necessity, due either to a requirement for advanced airway management or to complex aorto-iliac anatomy. The authors concluded that TAVR can be performed with a minimalist approach in the catheterization laboratory with low morbidity and mortality, reduced costs, and equal effectiveness as compared to the standard hybrid operating room approach.
COMMENTARY
This intriguing paper makes a convincing argument that with appropriate patient selection and in the right hands, a proportion of TAVR procedures may be safely performed using a minimalist approach. This was not a randomized comparison. All reported procedures were done after Emory had performed more than 100 procedures, so the learning curve was presumably not a big issue. Despite this, however, the MA procedures were performed for the most part later in time, when the operators had more experience. This, or alternatively simple chance in this relatively small data set, is the more likely explanation for the lower procedural mortality among the MA group. Reduced procedure times, room times, hospital length of stay, and costs, however, are certainly real.
It is worth noting that all procedures reported here were performed with the first-generation Sapien valve with its very large 22F and 24F sheaths. Smaller procedural sheaths currently available with the second-generation Sapien and with the Corevalve platforms should make the transfemoral approach available to a greater proportion of patients. With good pre-procedural multimodality imaging (with CT, TTE, and TEE), patients who are good candidates for such minimalist transfemoral procedures can be identified with a high degree of confidence. As the experience of U.S. centers continues to grow and devices with smaller profiles are made available, a shift toward this method appears likely. The need for detailed evaluation by the Heart Team will remain essential, however, to ensure that patients are appropriately selected for this approach.