CRT 2010 Renal Embolic Protection Devices Desirable but

CRT 2010 Renal Embolic Protection Devices: Desirable, but How Effective? MICHAEL H. WHOLEY, MD, MBA CENTRAL CARDIOVASCULAR INSTITUTE UNIV. OF TEXAS AT SAN ANTONIO 2/22/2010 1: 55 to 2: 05

DISCLOSURES Michael H. Wholey, MD I have no real or apparent conflicts of interest to report. I intend to reference unlabeled/ unapproved uses of drugs or devices in my presentation. I intend to reference carotid stenting and filter devices.

Are Embolic Related Complications from Renal Artery Stenting A Serious Problem ? Procedure-Related Complications Rate of Worsening Renal Function and/or Hypertension following Stents

Renal stent case: JR • Right renal stent undersized • 95% left renal artery stenosis

Renal stent case: JR Note: Upper pole present • Tried 0. 014” but not enough support • Lesion crossed with 0. 018” wire and vertebral soft touch catheter through 8 Fr guide catheter • Dilated with 4 mm PTA

Renal stent case: JR Loss of upper pole branch

Renal stent case: JR • One month follow up: on plavix, restoration of upper pole branch

What is the Rate of Embolic. Related Complications From Renal Artery Stenting? No. of Pts. No of Ather. Emb Boisclair 1997 33 4 (12%) Van De Ven 1995 24 2 (8%) Wilms 1991 11 2 (18%)

Cholesterol Emboli: Cause of Renal Failure n n n Rapid or insidious progression of renal failure In older patients with generalized arterial disease, cholesterol emboli can create a similar clinical picture as bilateral renal artery stenosis causing progressive renal insufficiency or worsening hypertension Diagnosis by biopsy n Vidt DG, Annu Rev Med 1997; 48: 375 -85

Are Embolic Related Complications from Renal Artery Stenting A Serious Problem ? Procedure-Related Complications Rate of Worsening Renal Function and/or Hypertension following Stents

GOALS OF RENAL ARTERY STENTING CURE RENOVASCULAR HYPERTENSION n RECAPTURE OR PRESERVE RENAL FUNCTION n INCIDENTAL STENOSIS: PREVENT ISCHEMIC NEPHROPATHY n How Have We Done in Achieving These Objectives ?

RESULTS OF RENAL STENTING IN TREATING RAS HTN

RESULTS OF RENAL STENTING IN RAS RENAL DYSFUNCTION

Are Poor Post Procedural Results Due to Embolic Debris ?

What’s Wrong With Renal Artery Stenting? Angioplast y Distal protection Stent post dilatation Debris release Distal protection Covered Stents Plaque fracture Debris release Plaque strainer Cheese Grater effect

n Causes for Embolic Debris: Efforts to Improve Technology Guidewire: 0. 014’ Platform replacing 0. 035” n Coronary or Carotid Approach n Minimizing time and maneuvers within renal artery n

n Causes for Embolic Debris: Efforts to Improve Technology Guidewire: n n 0. 014’ Platform replacing 0. 035” Avoid Manipulation Primary Stenting n Avoid Post Dilatation (if possible) n “No-Touch” and “Limited No-Touch” Technique n

No Touch Technique • With the guide tip not engaging the renal artery, cross with the 0. 014” wire past the lesion • Pull the extra wire out, then advance balloon and stent to deploy

No Touch Technique

Avoid Engaging Guide/Sheath into Renal Artery Origin

Dissection from catheter

Still, There is a Need for Embolic Protection

Distal Protection: Renal Stenting n Filters: Angioguard n Others (EPI, Accunet, Spider) n n Occlusion Percu. Surge n Fibernet n

Renal Artery Stent Balloon Occlusion n Percu. Surge Device is inflated distal to lesion n Stent deployed proximally n Embolic material is trapped inside vessel and aspirated

Percu. Surge Case Max Amor, MD, Nancy, France

Goal of Embolic Protection Devices

RESIST (Embolic Protection and Platelet Inhibition During Renal Artery Stenting) n studied the relationship between embolic protection and the GP IIb/IIIa inhibitor Abciximab used during renal artery stenting. Courtesy Eric Dippel,

RESIST (Embolic Protection and Platelet Inhibition During Renal Artery Stenting) n n Studied the relationship between embolic protection and the GP IIb/IIIa inhibitor abciximab used during renal artery stenting. Overall, this study demonstrated an unexpected positive interaction in protecting renal function when using both an EPD and abciximab in RAS. This benefit was not seen with using an EPD alone or abciximab alone. This was a small study and it will need to be demonstrated whether or not these results can be repeated. n Cooper CJ, Haller ST, Colyer W, et al. Embolic protection and platelet inhibition during renal artery stenting. Circulation 2008; 117: 2752– 276

Holden: New Zealand Experience Jan 1999 to July 2006, 124 RAS were treated in 105 patients with poorly controlled hypertension (72 males and 33 females), mean age was 64, with renal stenting with distal protection n Devices n n Occlusion balloon (Percusurge): 46 procedures n Filters: 76 procedures - EPI (Boston Scientific): 59 - Angioguard (Cordis): 7 - Emboshield (Abbott Vascular, ): 6 - Fiber. Net (Lumen Biomedical, ): 4 Accunet (Guidant, ): 2

Holden: New Zealand Experience n Results n 100% Tech Success n 2 pts developed an arterial spasm (one with Percusurge, one with EPI filter) n No dissection

Angioguard Filter Case

Holden: New Zealand Experience n Particulate Analysis n With the Percusurge technique , 100% aspiration visible debris in all patients n n n The aspirated particles: Their number varied from 13 to 208 per procedure and diameter ranged from 38 to 6206 µm (mena 201. The particles were atheromatous plaques, cholesterol crystals, necrotic cores, fibrin, fresh thrombi, organized thrombi, platelets, and macrophage foam cells, thrombogenic lipoid We removed, with filters, visible debris in 80% of the cases. n Two filters were totally blocked by large particles, with flow being totally interrupted, and 2 other filters were almost totally blocked with ® visible debris were low flow. The flow.   • With the new filter Fiber. Net removed in all cases. Of the particles, 70% were less than 100 microns. Average area for Fiber. Net® debris captured: 117. 1 mm 2

Holden: New Zealand Experience n Results n Hypertension n During the 18 mos follow up, no difference with other published series of patients treated without protection. n No. of medications also declined (2. 8 vs. 1. 2). n n Nineteen patients were cured (18%), 61 improved (59%), and 25 remained unchanged (22%) Renal Dysfunction n At 3 years (37 patients), 93% of the patients remained stabilized (n = 26) or improved (n = 9). 20 pts have RF deterioration

Complexities with Renal Protection ? n Are we making a simple, quick procedure more complex with potential problems? n Anatomical Issues: n Early branching of key vessels n Larger profile of filter crossing lesion n Dissection/Damage to vessel n Not being able to recover filter n Filter getting stuck on stent n Cost/CMS Reimbursement

Embolic Filter Issues: • Which Vessel do you protect ?

Embolic Filter Issues: Does the System Provide Enough Support ?

Distal Protection

Distal Renal Artery Disease: Is it the real Culprit in Htn and CRF ? n Main Renal Artery n Divisions (Ant/Post) n Segmental n Branches Intralobular Questions: 1. Is it too late to treat the main ostium with stenting ? 2. Or, with the presence of distal disease, should we be much more aggressive in treating lesions >50% 3. We need to be much aggressive in diagnosing early renal Htn and treating medcially

Distal Renal Disease n How Common is it?

Conclusions n Is renal stenting with distal protection the answer? Maybe. Is solution renal protection versus improved techniques? n Real problem, is whether renal stents will grow following certain trials (ASTRAL). n

The End