Catheterization and Cardiovascular Interventions 54:346 –349 (2001)
Transradial Renal Angioplasty: Initial Experience John Shuck,*
MD,
Amid Khan, MD, Nick Cavros, MD, Stylianos Galanakis, and Vishal Patel, MD
MD,
We report our early experience of a new technique of renal angioplasty utilizing the radial approach. Certain anatomic considerations continue to make access from above via the arm the preferable approach in selected patients in renal artery stenosis. We have utilized the transradial technique for renal artery angioplasty and stenting successfully in four patients. The development of coronary guidewire (0.014ⴖ)-based peripheral balloons and stent delivery systems has miniaturized equipment sufficiently to make the transradial approach attractive. Present equipment allows for stenting of renal arteries of up to 7 mm with the use of 6 Fr guiding catheters. Present equipment length remains a limitation in taller patients. The transradial approach should be considered in those patients with renal artery or aortoiliac anatomy favoring an approach from the arm. Cathet Cardiovasc Intervent 2001;54:346 –349. © 2001 Wiley-Liss, Inc. Key words: transradial; renal angioplasty
INTRODUCTION
Transradial coronary angioplasty was first carried out by Campeau [1] in 1989. Transradial angioplasty and stenting is now an established procedure in interventional cardiology following the pioneering work by Kiemeneij et al. [2]. The transdradial approach has several advantages which have been discussed elsewhere. The technique has been made possible by advances in catheterbased technology, which have provided smaller-profile stents and balloons. Such technology has now provided balloons and stents for the peripheral circulation, which may be utilized through 6 Fr guiding catheters. Balloons up to 7 mm and stents deployable to nearly 8 mm are now available in systems based on coronary guidewire (0.014⬙) compatibility. This has in turn allowed for the use of the transradial technique as a substitute for the brachial approach in certain peripheral vascular interventional procedures. Renal angioplasty and stenting has become an accepted technique for the treatment of renovascular hypertension and more importantly ischemic nephropathy [3,4]. The technique has evolved from initial 8 Fr systems utilizing guiding catheters and stents hand-crimped onto balloons [5] to 6 Fr guide-compatible systems utilizing premounted stents. While the femoral approach predominates, certain anatomic features have always made access from above preferable in certain patients [6]. Marked inferior angulation of the renal artery, particularly in patients with calcified vessels, may make the femoral approach difficult (Fig. 1). In addition, many patients with renal arterial disease have severe aortoiliac © 2001 Wiley-Liss, Inc.
occlusive disease, making femoral access difficult or impossible. We have recently utilized the transradial approach for renal arterial intervention. This has been accomplished with standard commercially available equipment. We herein report our initial experience with this evolving technique. CASE REPORTS
We describe four cases of successful renal angioplasty via the transradial approach using FDA-approved devices. Baseline clinical characteristics of patients and diagnostic procedures performed prior to intervention with their results are listed in Table I. Procedure
All patients undergoing transradial renal angioplasty were screened for a strongly palpable radial pulse and a positive Allen’s test. A 6 Fr arterial sheath (Cook, Bloomington, IN) was placed percutaneously into the right radial artery. Nicardipine and nitroglycerine were infused for prevention of spasm and 5,000 unit of heparin were administered. A 6 Fr MultipurMain Line Health Heart Center, Lankenau Hospital, Wynnewood, Pennsylvania *Correspondence to: Dr. John Shuck, Main Line Health Heart Center, Lankenau Hospital, 100 Lancaster Avenue, Suite 358, MOBE, Wynnewood, PA 19096. E-mail:
[email protected] Received 26 March 2001; Revision accepted 22 July 2001
Transradial Renal Angioplasty
347
TABLE I. Baseline Patient Characteristics* Age, years Case 1
72
Case 2
55
Case 3
82
Case 4
79
Sex Comorbid status
Baseline serum creatinine (mg)
Diagnostic procedure prior to intervention
1.1
Renal angiography
1.1
Renal angiography
2.0
Renal angiography
3.0
MR angiography
Female hypertension, CHF, NIDDM, PVD Female refractory hypertension, previous MI, PVD Female hypertension, CHF, PVD, previous renal failure Female hypertension NIDDM, progressive renal failure
Renal artery involvement 90% Left renal artery ostial stenosis 99% Left renal artery ostial stenosis 90% right and 95% left renal artery ostial stenosis 95% left and 90% right renal artery ostial stenosis
*CHF ⫽ congestive heart failure; PVD ⫽ peripheral vascular disease; NIDDM ⫽ noninsulin-dependent diabetes mellitus.
Fig. 1. Case 1 demonstrating left renal artery ostial stenosis (arrow). Note the inferior angulation of the artery and natural alignment of the multipurpose catheter from above.
Fig. 2. Case 1 postangioplasty and final stent deployment. The 4.5 ⴛ 18 mm Herculink stent (arrow) was dilated with a Viatrac 5.5 ⴛ 20 mm balloon to 14 atm for a final lumen of 6 mm.
pose guiding catheter (Cordis, Miami, FL) of 100 cm length was utilized for selective left renal arteriography in all patients. The internal diameter of this guide is 0.067⬙. The stenosis was crossed with a 0.014⬙ coronary guidewire and initial balloon angioplasty was performed. The various guidewires, balloons, and stents used in the four patients are listed in Table II. Stenting was performed utilizing Herculink stents (Guidant, Santa Clara, CA). Various inflation pressures utilized for balloon and for stent deployment are also listed in Table II. Final dilatation was performed with a Viatrac Balloon (Guidant). Final angiography and gradient determination were performed to confirm procedural success with no residual angiographic stenosis and resolution of the pressure gradient across the lesion (Fig. 2). The catheter and sheath were removed immediately with hemostasis obtained by local pres-
sure only. There were no complications; patients were allowed to ambulate within 1 hr postprocedure. The following day, there was no hematoma over the radial access site and the pulses were intact in all patients. DISCUSSION
Renal artery angioplasty and stenting for renovascular disease has recently been reviewed [7]. The use of stenting following angioplasty has greatly reduced restenosis rates and should always be performed in patients with atherosclerotic ostial renal arterial disease [8] (Fig. 3). Precise placement of the stent is felt to be critical to minimize the chances of restenosis. Optimally, 1 to 2 mm of the stent should protrude into the aorta to minimize encroachment of aortic atherosclerotic plaque over the ostium of the renal artery (Fig. 4).
348
Shuck et al.
Fig. 3. Case 4 demonstrating severe right renal artery ostial stenosis (arrow). The aorta is severely atheromatous and distal renal vessel filling is markedly attenuated. Again, note the natural coaxial alignment of the multipurpose guiding catheter.
Fig. 4. Case 4 postangioplasty and final stent deployment. The 4.5 ⴛ 18 mm Herculink stent (arrow) was dilated with a Viatrac 6.0 ⴛ 20 mm balloon to 14 atm for a final lumen of 6.5 mm. Note the improved filling of the distal renal vessels postrevascularization.
In inferiorly angulated renal arteries, precise placement of the stent during deployment can be difficult from the femoral approach. This is particularly the case in heavily calcified vessels. Approaching such a vessel from
above allows for a much more natural orientation of balloon and stent with the vessel, thus allowing for a more precise positioning of the stent. Approaching the vessel from above has traditionally relied on brachial access. This report demonstrates the feasibility and technique of radial access. Several aspects of our technique warrant discussion. We have routinely predilated lesions before stent placement; however, primary stenting can be performed. If predilatation is performed, the initial balloon should not exceed the stent delivery balloon size, the better to allow the stent to grip the lesion at deployment. We have been able to deploy the premounted Herculink stent on 5.0 mm balloons through 6 Fr guiding catheters of 0.067⬙ internal diameter. Larger-lumen 6 Fr guiding catheters are available with internal diameters of 0.070⬙ (Medtronic, Minneapolis, MN). Larger balloon stent sizes may require a larger guide. For final stent deployment, we have utilized Viatrac balloons up to 7 mm in size. Difficulty in removal of the balloon after inflation may be encountered but can be prevented by using very dilute contrast and allowing at least 1 min of deflation before attempting to withdraw the balloon into the guide. A major limitation of the transradial technique for renal arterial intervention is the length of presently available stent delivery equipment. All of our patients were less than 65⬙ in height. This allowed for the use of more standard 100 cm guiding catheters with the 135 cm working length of the Herculink stent delivery system. Guides of 110 cm and 125 cm are available; however, caution is indicated, as over 10 cm of working length is lost with the use of the Tuohy-Borst adapter. Thus guides of 125 cm must be shortened to allow for exit of the balloon stent from the guide tip. Fortunately, most renal interventions are performed within a few centimeters of the renal artery ostium. Longer guides can be shortened by removing the hub of the catheter and adapting the diaphragm portion of a sheath 1 Fr size smaller. This also obviates the need for a Tuohy-Borst adapter for pressure monitoring and contrast injection. Radial artery access for renal artery intervention may utilize either the right or left radial artery. We have utilized the right radial approach as this offered the greatest ease of use in our catheterization laboratory. In most patients, the left-sided approach offers a shorter distance to the descending thoracic aorta. With access from either side, severe tortuosity and angulation of the innominate or subclavian artery may be encountered, particularly in elderly hypertensive patients. These difficulties can be overcome with the use of stiffer guidewires. In summary, we believe transradial renal angioplasty and stenting to be a promising technique in selected patients. Present equipment allows for stenting of vessels up to 7 mm with the use of 6 Fr guiding catheters.
Transradial Renal Angioplasty
349
TABLE II. Devices Used in Transradial Renal Angioplasty Guiding catheter Case 1
Case 2
Case 3
Case 4
6 French multipurpose catheter; length, 100 cm 6 French multipurpose catheter; length, 100 cm 6 French multipurpose catheter; length, 100 cm 6 French multipurpose catheter; length, 100 cm
Guidewire
Balloon for predilatation
Stent
Balloon for final dilatation
0.014⬙ All-Star
Viatrac 4 ⫻ 20 mm
Herculink 4.5 ⫻ 20 mm, deployed at 14 atm
Viatrac 5.5 ⫻ 20 mm, inflated to 14 atm
0.014⬙ BMW
Cross-sail 4.0 ⫻ 15 mm (Guidant)
Herculink 4.5 ⫻ 18 mm, deployed at 15 atm
Viatrac 6.0 ⫻ 20 mm, inflated to 10 atm
0.014⬙ BMW (right); 0.014⬙ choice PT (left) 0.014⬙ Choice PT coronary guidewire (left and right)
Viatrac 4.0 ⫻ 20 mm (right and left)
Herculink 5.0 ⫻ 18 mm (right and left), deployed at 15 atm
Cross-sail 4.0 ⫻ 20 mm (left and right)
Herculink 4.5 ⫻ 18 mm (left and right), both deployed at 15 atm
Viatrac 5.5 ⫻ 20 mm (right); Viatrac 6.0 ⫻ 20 mm (left), inflated to 15 atm Viatrac 6.0 ⫻ 20 mm (right); Viatrac 6.5 ⫻ 20 mm (left), inflated to 14 atm
Equipment length remains a limitation in taller patients. The transradial approach should be considered in those patients with renal artery or aortoiliac anatomy favoring an approach from above.
4.
5.
REFERENCES 1. Campeau L. Percutaneous radial artery approach for coronary angiography. Cathet Cardiovasc Diagn 1989;16;3–7. 2. Kiemeneij F, Laarman GJ, de Melker E. Transradial artery coronary angioplasty. Am Heart J 1995;129:1–7. 3. Canzanello VJ, Millan VG, Spiegel JE, et al. Percutaneous transluminal renal angioplasty in management of atherosclerotic reno-
6.
7. 8.
vascular hypertension: results in 100 patients. Hypertension 1989; 13:163–172. Dorros G, Jaff M, Mathiak L, et al. Four-year follow-up of PalmazSchatz stent revascularization as treatment for atherosclerotic renal artery stenosis. Circulation 1998;98:642– 647. White CJ, Ramee SR, Collins TJ, et al. Guiding catheter-assisted renal artery angioplasty. Cathet Cardiovasc Diagn 1991;23:10 –13. Kaukanen ET, Mannien HI, Matis PJ, et al. Brachial artery access for percutaneous renal artery interventions. Cardiovasc Intervent Radiol 1997;20:353–358. Safian RD, Textor SC. Renal artery stenosis. N Engl J Med 2001; 344:443– 449. White CJ, Ramee SR, Collins TJ, Jenkins JS, Escober A, Shaw D. Renal artery stent placement: utility in lesions difficult to treat with balloon angioplasty. J Am Coll Cardiol 1997;30:1445–1450.
