TECHNINIQUES OF RENAL ARTERY STENTING Aravinda Nanjundappa, MD Professor of Medicine and Surgery West Virginia University Charleston, WV

Disclosure Statement of Financial Interest I, Aravinda Nanjundappa, DO NOT have a financial interest/arrangement or affiliation with one or more organizations that could be perceived as a real or apparent conflict of interest in the context of the subject of this presentation.

Indications for revascularization of RAS Hemodynamic RAS = > 50-70% stenosis + Peak gradient >20 mmHg or mean gradient >10 mmHg

SCAI consensus 2014: RAS maybe appropriate for significant renal artery stenosis Cardiac disturbance: severe HTN with Flash pulmonary edema or ACS Resistant HTN on diuretic and maximal dose of anti hypertensives Ischemic nephropathy: Bilateral severe renal artery stenosis or unilateral stenosis in solitary kidney with GFR <45

Patient Preparation Antiplatelet Hydration HCO3- (?) ASA and Clopidogrel at least 5-7 days Hydration HCO3- (?) N-acetylcysteine, if renal insufficiency 600 mg bid Visipaque® for high risk patient

Abdominal Angiography Renal arteries usually originate at the L1/L2 level So, position pigtail at about T12 Use digital subtraction angiography

Abdominal Aortography

Non-selective Abdominal Aortogram Exclude presence of accessory RA Demonstrate disease of the aorta (eg., AAA) Identify origin of the RA’s Facilitate placement of diagnostic catheter and guide catheter Avoid unnecessary “windshield wiping” in aorta

Cholesterol embolization

LAO 20° Lt Rt Lt

Angiography: Gold Standard AP View 20° LAO View LAO 10-20°

Common Femoral approach

Cobra JR 4 IMA AR 1 Lateral take-off

RC 2 HK 1 Contra 2 SOS Omni 2 Inferior take-off

Sos-Omni Engagement

Brachial approach Iliac or aortoiliac disease Downward take off RA’s

Selective Angiography 5/6 French Insist on backflow and no pressure damp before injecting Use 3 cc syringe on manifold- forces one to use less contrast Contrast Dilute by 50:50 2-6 cc per injection with good reflux

Don’t inject if pressure damp

Equipments 5/6 Fr diagnostic catheter 7-Fr, 55 cm RDC guide catheter JR4, IMA, 7-Fr, 55 cm RDC guide catheter 0.014-inch extrasupport wire IVUS (?) Predilate balloon ? Balloon expandable stent Directly stent?

Guiding Catheter IM RDC RDC 1

Medication Unfractionated Heparin - 50 units/kg (ACT 200-250 sec) No post procedure heparin

Techniques for guide engagement Direct engagement Telescoping technique Exchange technique No touch technique

Direct engagement

Telescoping technique Preload diagnostic through rotating hemostat valve and guide cath, advance over wire to renal

Exchange technique 0.018 guidewire (more supportive wire required to do the excahnge)

No touch technique

Renal Stenting Technique B C D E F Monitor pain during balloon inflation

Potential Mechanisms of deterioration in renal function post renal intervention Contrast Reperfusion injury Distal embolization Obstruction to flow and renal infarction (but, with normal renal function, up to 50% of nephron mass may be lost without change in Cr) Inflammatory response from cholesterol emboli Increased ESR Urinary eosinophils

Stent Size and Restenosis rates Reference Vessel Diameter, mm Restenosis Rate, %

Say NO!! To Hostile aorta and aneurysm

92 year old physician with uncontrolled HTN, CHF recurrent episodes 92 year old physician with uncontrolled HTN, CHF recurrent episodes. CT scan shows 90% stenosis of the left renal artery

Follow-up DAPT 1 month (? Data) Clinically driven follow up Duplex ultrasound or CTA – to detect restenosis MRA – limited to use due to metallic artifact