P-071 - LEARNING CURVE AND LONG-TERM CLINICAL RESULTS OF THORACIC ENDOVASCULAR ANEURYSM REPAIR WITH THE TERUMO RELAY STENT-GRAFT

TOPIC:
Thoraco-abdominal Aortic Disease
AUTHORS:
Leone N. (Department of Vascular Surgery, Ospedale Civile di Baggiovara, Azienda Ospedaliero-Universitaria di Modena, University of Modena and Reggio Emilia ~ Modena ~ Italy) , Bartolotti L. (Department of Vascular Surgery, Ospedale Civile di Baggiovara, Azienda Ospedaliero-Universitaria di Modena, University of Modena and Reggio Emilia ~ Modena ~ Italy) , Gennai S. (Department of Vascular Surgery, Ospedale Civile di Baggiovara, Azienda Ospedaliero-Universitaria di Modena, University of Modena and Reggio Emilia ~ Modena ~ Italy) , Andreoli F. (Department of Vascular Surgery, Ospedale Civile di Baggiovara, Azienda Ospedaliero-Universitaria di Modena, University of Modena and Reggio Emilia ~ Modena ~ Italy) , Pizzarelli G. (Department of Vascular Surgery, Ospedale Civile di Baggiovara, Azienda Ospedaliero-Universitaria di Modena, University of Modena and Reggio Emilia ~ Modena ~ Italy) , Silingardi R. (Department of Vascular Surgery, Ospedale Civile di Baggiovara, Azienda Ospedaliero-Universitaria di Modena, University of Modena and Reggio Emilia ~ Modena ~ Italy)
Introduction:
Thoracic endovascular aortic repair (TEVAR) represents the current first-line treatment option for different aortic diseases. The long-term aortic survival is satisfactory.1 However, major adverse events (MAEs) and endoleaks occur requiring ongoing research and refinements.1,2 The Relay stent-graft (Terumo Aortic, Sunrise, FL, USA) is a commercially available device being implanted 2005. This graft has been evaluated showing satisfying results in terms of clinical outcomes (short- and mid-term), configuration (bare and non-bare stent) and profile.3 However, an evaluation of the Relay stent-graft learning curve has never been published leading us to undertake a detailed analysis of our experience. Our aim was to define the learning curve of a current TEVAR device analyzing procedural variables during the learning phase and their impact on long-term outcomes.
Methods:
Between November 15th, 2005 and September 30th, 2021, 418 thoracic stent-graft implantations were performed in our center with 220 consecutive TEVAR undertaken with the Relay stent-graft being included in the present analysis. Standard TEVARs for each major aortic thoracic disease were included excluding thoraco-abdominal, arch fenestrated/branched devices and/or chimneys. Stent-graft implantation with different manufacturer were excluded. The primary outcome was the learning curve analysis using the cumulative sum (CUSUM) charts method.4 The secondary outcomes were: 30-day MAE; procedural details (additional maneuvers, operative and fluoroscopy time, and contrast volume); 30-day clinical success; endoleak rate; aortic-related reintervention; overall and aortic-related survival. The CUSUM technique depicts the relationship between case number (x-axis) and the learning composite outcome which included 30-day MAE and additional aortic maneuvers (y-axis). The learning curve achievement is demonstrated by the CUSUM slope remaining steadily below the acceptable learning-related composite outcome. The latter, represented by a straight horizontal line in the charts, is the cohort incidence of the composite outcome (23.08%) set as default threshold by the statistical software. Results were presented into four quartiles of experience accounting for 55 patients each (Q1 to Q4). Clinical outcomes were presented into four quartiles in tables and as first two (Q1-2) vs latest two (Q3-4) quartiles in the text, aiming to better elucidate difference across the median. Uni- and multi-variable logistic regressions analyzed the risk factors for MAE along with Cox regression evaluating those for endoleak.
Results:
The learning curve was reached after 10 patients as displayed in Figure 1. Mean follow-up was 4.5±3.9 years. Secondary outcomes improved significantly over experience. Details per quartile were reported in Table 1. Thirty-day MAE occurrence was 14.5% vs 11.8% (P=0.550). Additional maneuvers (P=0.009), access-vessels additional maneuvers (P=0.010), operative time (P=0.004), Relay Plus (P=0.001), and multiple stent-grafts implantation (P=0.034) were independent risk factors for MAEs. Operative time (125.9±66.7 vs 86.7±48.5 min, P<0.001), contrast volume (185.4±112.8 vs 140.5±88.2 mL, P=0.003), and fluoroscopy time (12.4±12.7 vs 8.8±7.5 min, P=0.017) decreased significantly. Trends over experience of the above-mentioned procedural details were represented in Figure 2. Late endoleak occurrence was 19.5% with a non-significant reduction (21.8% vs 17.3%, P=0.395). Fluoroscopy time (P=0.008) and contrast volume (P=0.018) were independent risk factors for endoleak. Late aortic-related mortality was 2.3%, being a consequence of endoleak-related complications in all cases. Globally, a reduction of aortic-related mortality (both early and late) was observed between Q1-2 vs Q3-4 (13.6% vs 6.4%; P= 0.072).
Conclusion:
The Relay thoracic stent-graft demonstrated a short learning curve (10 patients) in a high-volume endovascular center. Intraprocedural variables (contrast volume, operative and fluoroscopy time) showed significant improvements over time. Moreover, they were significantly associated with major adverse events and late endoleak occurrence. The Relay presented a short learning curve with satisfactory long-term supporting its ongoing implantation.
References:
1. Gennai S, Leone N, Bartolotti LAM, Covic T, Lauricella A, Andreoli F, et al. Endoleak outcomes with different stent-graft generations in a 25-years thoracic endovascular aortic repair experience. Vascular. 2021;17085381211051486. 2. Harris DG, Olson SL, Panthofer AM, Matsumura JS, DiMusto PD. A Frailty-Based Risk Score Predicts Morbidity and Mortality After Elective Endovascular Repair of Descending Thoracic Aortic Aneurysms. Ann Vasc Surg. 2020;67:90-9. 3. Riambau V, Zipfel B, Coppi G, Czerny M, Tealdi DG, Ferro C, et al. Final operative and midterm results of the European experience in the RELAY Endovascular Registry for Thoracic Disease (RESTORE) study. J Vasc Surg. 2011;53:565-73. 4. Fortea-Sanchis C, Escrig-Sos J. Quality Control Techniques in Surgery: Application of Cumulative Sum (CUSUM) Charts. Cir Esp Engl Ed. 2019;97:65-70.
ATTACHMENTS: