Nellix Endovascular System: Clinical Outcomes and Device Overview

Transcription

1 Nellix Endovascular System: Clinical Outcomes and Device Overview Jeffrey P. Carpenter, MD Professor and Chief, Department of Surgery CAUTION: Investigational device. This product is under clinical investigation outside of the United States. It has not been approved for clinical investigation or for marketing in the United States. MM0201 Rev. 01

2 Current State of EVAR Benefits vs. OSR in Multiple Trials Various Stent Graft Devices Available Proximal Infrarenal Fixation Proximal Suprarenal Fixation Anatomical Fixation Limitations Anatomies (e.g., Necks: <10mm, irregular, angulated) Complications Distal and lateral migration Endoleaks Occlusions Secondary Procedures

3 Case Control Studies RCTs EVAR Secondary Procedures Trial/Author Year N Follow-Up Years (Mean or Median) Secondary Procedures (% of Pts) EVAR EVAR DREAM OVER Carpenter Conrad Mehta , AbuRahma Dias Abbruzzese Pitoulias Kim Schermerhorn , Total 3.5 Years 18%

4 J Vasc Surg 2010;52: Number of Patients 1,768 Mean Follow-up [SD] 34 Months [30] % with Secondary Intervention 19.2% Type II Endoleak 40% Type I/III Endoleak 17% 7.7% of Pts Migration 14% Limb Occlusion 7.4% Other 22%

5 Pts Free from Sac Enlargement or Intervention Type II Endoleak Collateral Vessel Communication with Sac Lumbar, IMA, hypogastric, sacral, gonadal, or accessory renal artery 10-25% Incidence Post-EVAR 1,2,3 5-25% require intervention Predictors: o Patent IMA o Neck length o #Collaterals o Sac thrombus P< Rhee SJ, et al. AVS 2003;17; vanmarrewijk CJ, et al. EJVES 2004;27: Timaran C, et al. JVS 2004;39;

6 5-Year Costs Following EVAR ($US) Event No Yes Endoleak $5,706 $26,739 Secondary Intervention $3,668 $31,696 Efforts aimed at minimizing cost should emphasize technical and device modifications aimed at reducing endoleaks and the need for secondary procedures. Noll RE, et al. J Vasc Surg 2007;46:9-15.

7 Nellix Endovascular System Novel AAA Sac Sealing Technology Bilateral stents deployed to create blood flow lumens to distal anatomy Endobags filled with biostable polymer create seal Simple, predictable procedure Design Goals Treat wide range of AAA anatomies Reduce secondary procedures and follow-up surveillance Effectively prevent aneurysm rupture

8 Ovine Anterior Patch Model Preclinical Type II Endoleak Obliteration 31mm diameter aneurysm sac created Lumbar artery preservation

9 Nellix Device Design Stent Endobag Biostable Polymer Filled Endobags Around Stents

10 Sizing Matrix 14 Devices Device Lengths (mm) Aortic Neck Diameter (mm) Aortic Blood Lumen Diameter (mm) Common Iliac Artery Diameter (mm) 60, 80, 100, 120, 140, 160, , 80, 100, 120, 140, 160,

11 The Nellix Procedure Introduce catheters over.035 guidewires Balloon expand stents Fill Endobags with Polymer

12 Device Design and Displacement Forces 1 Baseline (Untreated) Proximal Bifurcation Mid Bifurcation Distal Bifurcation Total Displacement Force (N) Anterior Lateral Axial PA Segalova et al. Presented at the 2011 ASME Bioengineering Conference.

13 Hemodynamics after EVAR Modeling of the Effects of Nellix and Proximal Fixation EVAR Devices on Blood Flow Using Computational Methods 1 Pulsatile Flow Wall Shear Stress Patient Specific Geometry Pressure Drop Proximal Fixation Nellix Treated 1 Charles Taylor, PhD and Nathan Wilson, PhD - Cardiovascular Simulation Inc. 2008

14 Mean Wall Shear Stress 4.8 dynes/cm dynes/cm 2 Nellix Device Proximal Fixation Endograft 0 Mean Wall Shear Stress (dynes/cm 2 ) 10

15 Mean Pressure Drop Across Grafts Nellix Graft Infrarenal: mmhg Iliacs: mmhg Difference: 0.41 mmhg Proximal Fixation Endograft Infrarenal: mmhg Iliacs: mmhg Difference: 0.43 mmhg Infrarenal: mmhg Iliacs: mmhg Infrarenal: mmhg Iliacs: mmhg Difference: 0.57 mmhg Difference: 0.67 mmhg

16 Four International Centers Experienced in EVAR 1st Generation Nellix Device 34 Patients Enrolled 8/2008 to 1/2010 Independent CEC and DSMB Primary Endpoints at 30 Days: Safety: Complications vs. SVS surgical control Efficacy: Technical success + free from open repair Additional Endpoints: CE Trial Overview Clinical utility outcomes Long-term adverse events Independent Core Lab (M2S, Inc.) review of CT scans

17 Demographics and Risk Factors Demographic Result* (N=34) Male Gender 91% Age, years 71 ± 7.6 Total AAA Vol., ml 178 (68 363) AAA Sac Dia., cm 5.8 ( ) Blood Lumen Dia., cm 4.2 ( ) Neck Dia., mm 24 (18 31) Neck Length, mm 21 (5.0 50) Neck Angulation, 37 (9.1 72) Risk Factor Result* (N=34) CAD 56% CHF 17% COPD 39% Hypertension 68% PAOD 21% Prior CABG/PCI 56% Prior MI 26% Smoking 50% *Result shown as %, mean ± SD, or mean (range)

18 Preoperative Neck Anatomy (N=34) Short Neck (<10mm) Angulated Neck (>60 ) Large CIAA (>23mm) Any of the 3

19 Type II Endoleak Risk Factors (N=34) Multiple Lumbar Arteries (5+) Low Sac Thrombus Load (<25%) Patent IMA Any of the 3

20 Procedural / In-Hospital Outcomes Parameter Result * Device Implant Time (min) 70 (33-150) Fluoroscopy Time (min) 33 (13-71) Total Procedure Time (min) 127 (80-148) Estimated Blood Loss (ml) 165 (35-400) Polymer Fill Volume (ml) 73 (18-168) Time to Hospital Discharge (days) 3.8 (1-9) *Results shown as mean (range) 100% Procedural Technical Success One death on POD 3 (Multiorgan System Failure) determined by DSMB to not be device related

21 Primary Safety Results at 30 Days CEC Adjudicated Results Event Nellix (N=34) SVS Control (N=243) P-value Any Complication 1 (2.9%) 136 (56%) <.0001 Mortality 1 (2.9%) 7 (2.9%) --- Bowel Ischemia Myocardial Infarction 0 13 (5.3%) --- Paraplegia Blood Loss 1000mL (51%) --- Renal Failure 1 (2.9%) 7 (2.9%) --- Respiratory Failure 0 14 (5.8%) --- Stroke 0 3 (1.2%) --- *Results shown as number of patients with event (% of total)

22 Major Adverse Events to 2 Years CEC Adjudicated Results Event 0 30 Days (N=34) 31 Days to 1 Yr (N=33) >1 Yr (N=32) Pts with 1 MAE 1 (2.9%) 2 (6.1%) 1 (3.1%) Mortality 1 (2.9%) 1 (3.0%) 1 (3.1%) AAA-Related Mortality 1 (2.9%) 0 0 Bowel Ischemia Myocardial Infarction 0 1 (3.0%) 0 Renal Failure 1 (2.9%) 0 0 Respiratory Failure Secondary Procedure 1 (2.9%) 0 1 (3.1%) *Results shown as number of patients with event (% of total)

23 Secondary Interventions 34 Patients with up to 2 Year Follow-up 2/34 (5.9%) with Intervention Exploratory laparotomy for renal insufficiency on day 3 (no conversion) Embolization and stent insertion for distal Type I endoleak at 15 months Inadequate Device Length* *Commercially available AneuRx extension used intraop; Nellix extenders not available at this time.

24 Diameter (mm) Aneurysm Sac Stability 65 N=34 N=33 N=33 N=32 N= Pre-Op 1 Month 6 Months 1 Year 2 Years ± ± ± ± ± 9.0

25 Core Lab Evaluations to 2 Years 0% Aneurysm Rupture 0% Migration 0% Conversion to Open Repair 0% Stent Fracture 0% Endobag Failure 0% Type II, III, or IV Endoleak 0% Sac Expansion 0% Limb Occlusion

26 Nellix Pre and Post Implant Anterior Slide 27

27 Case Overview 6.0cm AAA with 10mm Length Neck and 3.5cm RCIAA Pre-Operative Post-Operative R hypogastric artery preserved with Nellix extender 1-Year

28 Elimination of Potential Type II Endoleak Pre-treatment large IMA Post-Nellix IMA trunk occluded Note marginal and superior rectal branches (arrows) ( neck ) Aorta 22 Max Sac Lumen 24 L iliac R iliac 13

29 Case Overview Large 7.6cm AAA with Low Thrombus Load Pre-Op 1 Yr Post-Op

30 Case Overview 5.4cm AAA with 5mm Length Neck and Bilateral CIAA >2.5cm Pre-Op 1 Month 1 Year No change in implant stability or sac diameter over time

31 Summary The initial safety and effectiveness of the Nellix sac sealing technology is very encouraging No Type II endoleak despite presence of risk factors Absence of rupture, conversion, stent occlusion, migration Low rate of secondary interventions Simplified surveillance (e.g., ultrasound) may be justified leading to reduced costs post EVAR Longer follow-up and increased experience needed

32 Current and Future EVAR Devices Profile Neck Neck Iliac Company Device (OD) Length Diameter Diameter Endologix AFX 19F 15mm 32mm 23mm Medtronic Endurant 18F - 20F 10mm 32mm 25mm Cook Zenith LP 16F - 18F 15mm 32mm 20mm Gore C3 18F - 20F 15mm 29mm 18.5mm Trivascular Ovation 14F - 15F 7mm 30mm 20mm Endologix Nellix* 17F 5mm 36mm 35mm JNJ Incraft 14F 15mm 31mm 22mm Terumo Anaconda 21F - 23F 15mm 31mm 21mm *Expected profile and indications for commercial device Nellix is expected to treat more AAA anatomies than other EVAR devices and is the only device that completely seals the aneurysm sac

33 Forward Looking Final device design enhancements and testing in process CE Mark anticipated with initial European introduction in 2012 US IDE anticipated to initiate 2012