Discussion
This analysis of transfemoral TAVI procedures performed at a single institution showed that, compared with a control group treated using the previous setup, the introduction of procedural refinements had no adverse effect on TAVI outcomes, but was associated with a reduction in the length of ICU and hospital stay and was cost saving. The main refinements that were introduced included switching from general anaesthesia to conscious sedation, using percutaneous access/closure in preference to surgical cut-down and omitting periprocedural TEE. With adequate proctor guidance, TAVI procedure using conscious sedation and ‘refinement’ is suited to be adopted by new centres starting TAVI procedures.
In the past, TAVI was usually performed under general anaesthesia and involved periprocedural TEE. However, as experience with TAVI has increased, some centres have moved towards a minimalist approach, whereby the procedure is performed in a catheterisation laboratory using local anaesthesia with or without conscious sedation and without periprocedural TEE. Meta-analyses of observational studies support the use of local anaesthesia/conscious sedation as an alternative to general anaesthesia in appropriate patients undergoing TAVI.16 29–31 This approach reduces the invasive nature of the procedure, as well as potentially reducing the resources required and the costs.18–20 It has also been shown that periprocedural TEE can be omitted without compromising outcomes after TAVI, and that this is associated with a reduced procedural time and shorter length of stay in hospital.22 32 Percutaneous access and closure can be used safely in appropriate patients and can facilitate quicker ambulation and improved comfort for patients.21 33 These procedural refinements were introduced at our centre without any adverse effects on TAVI outcomes, the incidence of complications or mortality.
Complications that can occur after TAVI include paravalvular leakage/aortic regurgitation, permanent pacemaker implantation, stroke and access-site vascular complications.34 35 The incidence of adverse events in the current study are consistent with rates reported previously.34 A trend towards a higher rate of post-TAVI pacemaker implantation was noted in the procedural-refinement group compared with the control group, although the difference did not achieve statistical significance. It is possible that this difference could relate to the valves used. At our hospital, the SAPIEN XT valve has been supplanted by the new-generation SAPIEN 3 valve over time. During the control period, patients received either a SAPIEN XT or a SAPIEN 3 valve, whereas during the procedural-refinement period all but one patient received a SAPIEN 3 valve. It was anticipated that this new-generation valve would facilitate the introduction of the procedural refinements such as the use of a conscious sedation pathway, because it uses a smaller diameter (14F/16F) femoral sheath, allows for percutaneous femoral closure and has an improved delivery system to facilitate precise positioning of the valve based on radiological guidance, as well as a new external skirt designed to minimise the risk of significant aortic regurgitation.36 An increased rate of pacemaker implantation has been reported with the SAPIEN 3 valve compared with the SAPIEN XT in some (but not all) studies; the risk appears to be declining as experience with the valve increases.37–40 There is some evidence the risk may be affected by implantation depth, oversizing and pre-existing right bundle branch block.41 42 Nonetheless, a meta-analysis of studies comparing the SAPIEN 3 and SAPIEN XT valves found that the SAPIEN 3 was associated with a higher rate of successful implantation, fewer perioperative complications and similar rates of permanent pacemaker implantation, cerebrovascular events and early all-cause mortality.43
Pressure on healthcare resources means that in addition to optimising outcomes it is important to develop treatment strategies that are cost-effective. Most of the costs associated with the index episode of care for TAVI relate to procedural/hospital-related factors.44 In particular, a prolonged stay in the ICU is associated with increased costs,44 and periprocedural complications can prolong length of stay and increase costs.45 The procedural changes we introduced led to a reduced need for ICU care after the procedure and a shorter overall length of stay in hospital. The mean ICU stay decreased by 52.1 hours and the mean hospital length of stay by 1.9 days in the procedural-refinement group compared with the control group. This is consistent with studies that have found that use of a local anaesthesia/conscious sedation pathway was associated with shorter procedure time and ICU and hospital stays compared with a general anaesthesia pathway,16 29–31 with a meta-analysis reporting mean differences of −0.18 days for ICU length of stay and −2.09 days for hospital length of stay.16 The analysis of costs in the current study showed that the procedural-refinement pathway was cost saving compared with the previous pathway. Although implantation costs were higher for patients in the procedural-refinement group, an overall reduction in costs was seen compared with the previous pathway, predominantly because of a shorter ICU stay. A mean cost saving of £3580 per TAVI procedure was achieved.
Most studies evaluating the effect of TAVI procedural refinements on costs have focused on the use of conscious sedation versus general anaesthesia pathways. These analyses have found that a local anaesthesia/conscious sedation pathway is cost saving compared with general anaesthesia.14 18 20 In a study that included a subgroup of patients given SAPIEN XT or SAPIEN 3 valves via the transfemoral route, the total direct cost was approximately 25% lower in the conscious sedation group compared with general anaesthesia (p<0.001), with significant reductions seen in each of the individual cost elements considered (anaesthesia, operating-room recovery, ICU, pharmacy and ward).20 ICU and hospital lengths of stay were significantly shorter in the conscious sedation group (30 vs 61 hours, p<0.001; and 4.9 vs 8.8 days, p=0.006, respectively).20 An earlier study, involving transfemoral TAVI with the first-generation SAPIEN valve, also found that a minimalist approach using conscious sedation in a catheterisation laboratory was associated with significantly lower mean hospital costs compared with a standard approach using general anaesthesia in a hybrid operating room (US$45 483 vs US$55 377, p<0.001); in this study, hospital costs included the cost of the valve but not physician fees.18 Again, a shorter ICU stay (22 vs 28 hours, p<0.001) and hospital length of stay (4 vs 6 days, p=0.01) were seen in the conscious sedation group.18
The current study has several limitations. The control group included some patients who received SAPIEN 3 valves as well as patients treated with SAPIEN XT valves; this will have blunted the effect of the higher cost of the SAPIEN 3 valve which would have been more apparent in the procedural-refinement group had there been a strict separation of valve types. However, in a routine clinical practice setting, multiple procedural refinements cannot generally be implemented all at once; there will often be overlap of certain elements over time. This also applies to the type of femoral access/closure used and the use of TEE. This could potentially have affected some outcomes in the study. In addition, the study included a relatively low number of patients. This may have limited the power to detect significant differences; clinically relevant differences may not have translated into statistical significance. Although the number of patients was relatively low, the analysis was based on an unselected consecutive series of patients undergoing transfemoral TAVI at the same centre either before or after the introduction of procedural refinements; data such as this from a real-world setting may be relevant for similar centres that perform TAVI. Finally, procedural refinements such as those described for this study are part of ongoing quality improvement processes which are never completed. As such, the analysis may need to be repeated at other points in the future.