Feasibility and applicability of coronary stent implantation with the direct brachial approach: Results of a single-center study

James Nolan, MD, Pbilllp Batin, MD, Colin Welsh, MRCP, Steven Lindsay, MRCP, James McLenachan, MD, Campbell Cowan, D Phil, and J o h n Perrins, MD Leeds, United Kingdom

Implantation of stents in selected patients improves outcome after coronary angioplasty. Newer antiplatelet regimes limit access site complications associated with stenting by the percutaneous femoral approach, but a substantial proportion of patients will require anticoagulant therapy for concomitant disease or will have peripheral vascular disease that prevents access from the leg. We investigated procedural success rates and outcome in consecutive patients undergoing elective stent implantation in our institution. In 73 patients who were receiving anticoagulation therapy and were stented by a direct approach to the left brachial artery, 98.6% of stents were successfully deployed, with a major vascular access site compli- cation rate of 1.4%. Equipment consumption, procedural success rate, and fluoroscopy time were similar in patients stented by the direct brachial or percutaneous femoral approach. Where the percutaneous femoral approach is precluded or patients arelanticoagulated, stent procedures can be successfully performed by the direct brachial approach with a low rate of access site comolications, even when larae-caliber guiding catheters are required. (Am Heart J 1997;134:939-44.)

Percutaneous tvansluminal coronary angioplas W (PTCA) is an increasingly common method of achieving myocardial revascularization for patients with sympto- matic ischemic heart disease. The number of PTCAs performed annually now exceeds the number of surgi- cal revascularization procedures in some developed countries. 1 Mthough PTCA is technically successful in the vast majority of patients with anatomically suitable lesions, abrupt vessel closure at or soon after the time of the procedure, which is associated with high rates of morbidity and mortality, will develop in 3% to 5% of patients. 2 Additionally, angiographic restenosis at the dilatation site, which is associated with recurrent symp- toms and a need for further revascularization proce- dures, will develop in 25% to 50% of patients. Since the first report of their use in the coronary circulation in 1987, 3 stents have emerged as the treatment of choice for acute or threatened vessel closure after PTCA. Additionally, two recent randomized trials have shown that elective placement of Palmaz-Schatz coronary

From the Department of Cardiology, The General Infirmary at Leeds. Received for publication Oct. 24, 1996; accepted July I, 199Z Reprint requests: James Nolan, MD, Department of Cardiology, D Floor, Yorkshire Heart Center, General Infirmary, Leeds LS1 3EX, United Kingdom. Copyright �9 1997 by Mosby- Year Book, Inc. 0002-8703/97/$5.00+0 411184911

stents (Johnson & Johnson Interventional Systems, Warren, N.J.) in selected patients reduces the rate of angiographic restenosis, clinical ischemic events, and need for revascularization compared with conventional balloon angioplasty. 4,5

A large proportion of interventional cardiologists use the perct, taneous femoral approach for stent implanta- tion procedures, but some patients cannot be treated by this access site because of peripheral vascular dis- ease or an excessive risk of major bleeding complica- tions associated with anticoagulant therapy. Recent case reports indicate that the direct approach to the brachial artery utilized by cardiologists for diagnostic catheterization can be modified to facilitate coronary stem implantation. 6,7 In view of the limitations imposed by reliance on the percutaneous femoral approach and tile potential advantages conferred by the direct brachial approach, we instituted a simulta- neous program of brachial and femoral procedures when we began coronary stenting in our institution. This report describes the results obtained in consecu- tive patients undergoing elective coronary stenting by the direct brachial approach in our unit in the 32- month period after the commencement of our stent program in January 1993 and compares the results with those obtained in consecutive patients who received elective stents by the percutaneous femoral approach during the same time period.

940 Nolon et aL

M e t h o d s Patient selection

Patients with angina uncontrolled by optimal medical ther-

apy associated with objective evidence of myocardial

ischemia (electrocardiographic ST-segment depression or a reversible perfusion defect at thallium scintigraphy) in asso-

ciation with typical symptoms were considered eligible for elective stenting. After diagnostic angiography, patients

unsuitable for stent implantation (prognostically important

coronary disease requiring coronary artery bypass grafting,

extreme target artery tortuosity, diffuse distal disease in target arteries, and target arteries <2.5 mm in diameter) were

excluded. In the remaining patients, those with stenotic

lesions of >700 were selected for elective stenting if their

lesion was in a high-risk site for restenosis (proximal left

anterior descending coronary artery or degenerated vein

graft) or if a suboptimal result with conventional balloon

angioplasty ~'as considered likely (American College of

Cardiology/American Heart Association task force type C

lesions). Patients were selected for elective stenting by the

brachial approach if (1) they had important symptomatic peripheral vascular disease, (2) they were already taking

anticoagulants, or (3) to facilitate early mobilization. During the study period all patients receiving coronary stents in our

institution w:ere treated with an intensive anticoagulant

regime. Patients selected for stenting by the brachial

approach were started on oral anticoagulants after the diag-

nostic angiogram, with the aim of achieving a target interna-

tional normalized ratio of 2.0 to 3.0 before their stent proce-

dure. Patients selected for stenting by the percutaneous

femoral approach received no oral anticoagulants before the

procedure but were managed with an intensive anticoagu-

lant protocol after stent implantation. All patients were pre- treated with aspirin.

Stent implantation protocol All procedures were carried out in a catheterization labo-

ratory equipped with a high-resolution digital cardiac imag-

ing system (Philips Medical Systems International). For pro- cedures performed from the leg, the femoral artery was

percutaneously punctured with a single-entry needle, and

an 8F valved introducer sheath was positioned with the modified Seldinger technique.

The left brachial approach required a change in the setup

of the catheterization laboratory, with the operator, assis- tanks, and ancillary equipment positioned to the left of the

patient and monitors moved to a position that allowed simul-

taneous catheter manipulation and visualization. After infil-

tration of local anesthetic, the brachial artery was identified and isolated by standard surgical dissection. A guide wire

was introduced to the brachial artery by a longitudinal arteri-

otomy, and an 8F valved introducer sheath was positioned over the guide wire and sutured to the skin. The properties

of standard, preshaped guiding catheters designed for trans-

femoral PTCA may be compromised when they are inserted

from the right arm, and adequate support for passage of

stent-loaded balloons may not be provided: 8 Tile use of the

left arm may improve performance characteristics (by

changing the catbeter's angle of entry and relative position within the aortic root) and increases the range of pre-

shaped guiding catheters that can be selected for brachial

PTCA. 9 \Ve therefore elected to perform all our arm proce-

dures with the left brachial approach. Our initial experience

indicated that left and right Judkins configuration guiding

catheters often performed suboptimally when inserted from the left arm and led to important modifications in our

approach to guiding catheter selection for these proce-

dures, t~ When approaching the right coronary artery or a

vein graft from the left arm, optimal coaxial alignment sta-

bility and support were usually provided by left Amplatz guiding catheters. The left Amplatz guiding catheters manu-

factured by different companies have slightly different con-

figurations, and we found that a catheter with a tight distal

loop (Pink Power, Schneider Europe) was usually prefer-

able. When approaching the left coronary artery from tile left arm, leftVoda or Amplatz guiding catheters usually pro-

vided optimal alignment and support, with the choice of

guiding catheter depending on the precise anatomic orien- tation of the left main stem.

After sheath positioning the stent deployment protocol was

similar in all patients. Ten thousand IU heparin was adminis-

tered into the side arm of the brachial or femoral sheath, and 5000 U boluses were repeated at 30-minute intervals.

Standard 8F guiding catheters were used, with an appropri-

ate curve chosen to maximize backup and .support during

tile stent deployment procedure. Before angiograpby 1 mg

intracoronary isosorbide dinitrate was given. Quantitative

coronary angiography in two orthogonal views was used to

measure the reference diameter of the adjacent nonstenosed coronary artery to facilitate selection of appropriate-sized

balloon catheters.

After angiography, a 0.014-inch guide wire (High Torque Floppy Wire, Advanced Cardiovascular Systems, Santa Clara,

Calif.) was advanced across the lesion. An ACS High Torque

Floppy Extra Support 0.014-inch guide wire was used in preference to the conventional guide wire for lesions in tor-

tuous vessels. A rapid-exchange, low-profile compliant bal-

loon catheter was used to predilate the target lesion for 60 seconds at low pressure (4 to 6 atm). The predilating balloon

was then deflated and removed.

Palmaz-Schatz stents ranging in size from 8 to 18 mm were used where possible. If difficulty in balloon catheter

advancement was experienced during the predilatation maneuver, or if the artery was excessively tortuous proximal

to the target lesion, an alternative stent was chosen at the operator's discretion (Wiktor stent, Medtronic Inc.,

Minneapolis, Minn., or AVE Microstent, Applied Vascular

Engineering Inc., Richmond, British Columbia). For long

American Heart Journal November 1997

Nolan etal. 941

lesions in vein grafts, Wallstents (Medivent Inc., Englewood, N.J.) were chosen.

The predilating balloon was used to deliver an appropri- ate-length manually crimped, bare-mounted Palmaz-Schatz stent deployed in the stenosed area at moderate (8 to 12 arm) pressure. After delivery, Palmaz-Schatz stent deploy- ment was optimized by dilatation within the stent to a high pressure (16 to 18 atm) with a short noncompliant balloon. In the small proportion of patients in whom an alternative stent was deployed, the premounted stents were positioned within the coronary stenosis on their delivery catheters and deployed as per the manufacturer's instructions.

Management of vascular access sites after stent implantation

After stent implantation patients in the femoral access group were transferred to the cardiac ward with the arterial sheath in situ. When the activated partial thromboplastin time was less than twice normal, the arterial sheath was removed ana the puncture site manually compressed until lmmostasis was achieved. A pressure dressing was applied to the puncture site overnight, and the patient was kept on bed rest for 36 h6urs. If difficulty in achieving hemostasis was experienced, a Femo-stop (Radi Medical Systems Inc.) was applied overnight. Heparin was recommenced 4 hours after sheath remo'~'al and titrated to maintain an activated partial thromboplastin time between two and three times normal. Warfarin was administered on the night of the procedure. Heparin infusion was continued until a stable international normalized ratio of two to three times the control value was achieved. Mobilization was delayed for a minimum of 24 hours or until satisfactory hemostasis was achieved.

After stent implantation in the brachial access group, the sheath was removed at tile end of the procedure and the arte- riotomy site was repaired with a purse-string suture. After achieving arterial hemostasis, the skin incision was closed and a small pressure dressing applied for 3 hours. Patients were encouraged to ambulate immediately after returning to the ward but were advised to refrain from movements of tile elbow joint for the remainder of that day.

Data collection, definitions, and statistics Clinical, procedural, and follow-up data were entered into

an advanced relational database specifically designed to facili- tate retrieval and follow-up of data relating to intercentional cardiology procedures, n For the purpose of in-hospital fol- low-up, the following definitions were applied. Clinically sig- nificant in-hospital stem occlusion equated with angiographi- cally proven target artery occlusion at the site of stem implantation in association with chest pain and ST-segment change. Major vascular complication equated with access site complication requiring transfusion, vascular surgical intercen- tion, or ultrasound-guided compression. Major peripheral ,~"as- cular disease was defined as symptoms of claudieation in association with reduced or absent femoral pulses.

Table h Stent selection and vascular access site in 213 elec- tive procedures

Palmaz-Schatz stent 243 (91.7%) AVE Micrastent 9 (3.4%) Wiktor stent 8 (3.0%) Schneider Wallstent 5 (1.9%) Single-stent procedure 196 (92.0%) Muttiple-stent procedure 17 (8,0%} Femoral approach 140 (66.0%) Brachial approach 73 (34.0%)

Table IhPatientcharac~ristics

Femoral Brachial

Age {yr) 58 + 10 59 _ 9 (range 39-78) (range 40-78)

Target artery (%) LAD 48 (34%) 24 (32%) tcx 18 (13%) 8 {I]%) RCA 56 {40%) 29 (40%) SVG 18 (13%) 12 {17%)

Peripheral vascular disease 0 (0%) 25 (34.2%) Cerebrovascular disease 6 (4.3%} 7 (9.6%) Diabetes mellitus 6 (4.3%) 9 (12.5%) Hyperlipidemia 84 (60.0%) 48 (65.8%} Hypertension 32 {22.8%} 37 (50.7%) Pretreatment with oral anticoagulants 0 (0%) 73 ( 100%}

LAD, [eft anterior descending coronary artery; LCX, left circumflex coronary arlery; RCA, right coronary artery; SVG, saphenous vein graft

Results During the 32-month period of this study, 938

PTCA procedures were performed in our institution.

In 213 procedures single or multiple stents were

implanted (Table I), and these cases form the basis

of this report. Seventy-three procedures were carried

out by the brachial approach because of major

peripheral vascular disease ( n = 25), a requirement

for oral anticoagulation because of valvular heart dis-

ease or atrial fibrillation ( n = 16), or the need to

facilitate early mobilization ( n = 32). All the brachial

patients had been receiving oral anticoagulant thera-

py before the procedure (mean international normal-

ized ratio 2.3 + 1), which was cont inued uninterrupt-

ed throughout their hospital stay. The remaining 140

procedures were carried out by the percutaneous

femoral approach.

Table II details patient characteristics for the two

groups. Diabetes mellitus, cerebrovascular disease,

hyperlipidemia, and hyper tension were more com-

mon in the bmchial group. In the femoral group, no

patient received oral anticoagulants before the proce-

dure, and all patients were free of significant periph-

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942 Nolan etal.

Table III. Procedural data grouped according to approach

Femoral Brachial approach approach

Number of guiding catheters 1.1 _+ 0.4 1.1 + 0.5 Guiding catheter configuration

Judkins 103 (73%) 8 (11%) Amplatz 4 {3%) 41 [56%) Voda 19 (14%} 24 (33%) Bypass 12 (9%) 0 (0%} Other 2 {1%) 0 {0%)

Maximum balloon size (ram) 3.7 + 0.5 3.7 _+ 0.5 Number of balloons 2.1 _+ 0.8 2.3 + 0.7 Fluoroscopy time (rain) 21 4- 12 18 4- 8

(range 7-90) (range 8-42)

Table IV. Major complications

Femoral Brachiol

No. of patients.with complications 12 (B.6%) 4 (5.5%) Stent occlusion 2 {1.4%) 2 (2.7%) Maior vascular complication 7 (5%) 1 ll.4%) Failure to deploy stent 2 (1.4%) 1 (1.4%) Death ! 2 (1.4%) 1 ( 1.4%)

eral vascular disease. The distribution of target arteries treated was similar in both groups.

Table III details procedural infommtion. The mean number of guiding catheters required was similar for both access sites. For the femoral approach, Judkins or bypass guiding catheters were initially selected arid provided adequate inmbati0n and backup in 82% of cases. In 17 femoral cases, Amplatz or Voda guiding catheters were initially selected to provide extra backup for procedures in tortuous coronary arteries. In two femoral cases, an ini- tially selected guiding catheter failed to inmbate the target vessel adequately. In these two cases a total of 12 differ- ent guiding catheters were tried before an appropriate configuration was obtained. For tim brachial approach, Amplatz or Voda guiding catheters were initially selected and provided adequate intubation and backup in 89% of eases. Tile remaining eight cases required a change to a right Judkins configuration because of problems with intubating the native right coronary ostium with an Amplatz guiding catheter. The maximum balloon size and number of balloons required was identical for both access sites. There was no significant difference in mean fluo- roscopy thne between the two groups.

Table IV details the complications that occurred in our patients. Stents were successfully deployed in 138 of the femoral procedures (98.6~ procedural success

rate). In the m,o remaining patients, undeployed stents

were retrieved from the coronary artery and conven-

tional balloon angioplasty was performed. Stents were successfully deployed in 72 of the brachial

patients (98.6% procedural success rate). In tim

remaining patient, a Wiktor stent was displaced from its balloon in the left main stem. The stent was

recrossed with a 1.5 mm balloon, successfully

retrieved from the coronary artery, and conventional balloon angioplasty was performed.

In-hospital stent occlusion occurred in ~ ' o (1.4%) of tim femoral patients. In one patient subacute stent throm-

bosis led to a limited myocardial infarction despite early

restoration of vessel patency by conventional PTCA; the

patient made an otherwise uneventful recovery. In the other patient acute occlusion of a WiMor stent occurred

in a large, dominant right coronary artery immediately

after the procedure, before the patient had left tim catheterization suite. Despite initial restoration of flow, it

proved impossible to control an extensive distal dissec- tion despite deployment of m'o further Palmaz-Schatz

stents. Inferior ST elevation and hypotension developed in this patient, who underwent urgent coronary artery

bypass grafting. Despite dais, intractable ventricular

arrhytimaias and hemodynamic compromise from right ventricular infarction developed, and tile patient died in

tile immediate postoperative period. A second death

occurred in tim femoral group after a rescue PTCA per-

formed for continuing angina and cardiogenic shock after an extensive myocardial infarct. Despite successful

revascularization the patient died 2 days later from intractable pump failure. In*hospital stent occlusion

occurred in two (2.7%) of the brachial patients. In one

patient subacute stent thrombosis led to a limited myocardial infarction despite early restoration of vessel

patency by conventional PTCA; the patient made an oth* erwise uneventful recovery. In the other patient subacute

stent thrombosis in a proximal left anterior descending

stent led to eardiogenic shock and death before further intervention was possible.

Major vascular complications occurred in 5% of the femoral group (95% confidence intervals 2.02% to

10.1%). One patient required transfusion for blood loss associated witi1 a large hematoma, and six patients required vascular surgical intervention or

ultrasound-guided compression for femoral artery aneurysms or pseudoaneurysms. Major vascular com-

plications occurred in only one patient (1.4%, 95% confidence interval 0.1% to 7.4%) in the brachial

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Nolan etal. 943

group, in whom ischemia of the hand required surgi- cal evacuation of a large hemat0ma.

Discussion This report details our early experience with elective

stent implantation and compares results in anticoagu- lated patients treated by the direct brachial approach with those obtained with the percutaneous femoral approach in conjunction with an intensive postproce- dural anticoagulant regime. Our strategy of electively stenting all lesions at high risk for restenosis and all lesions a t high angiographic risk for a suboptimal rest, lt with conventional balloon angioplasty can be implemented with a low rate of procedure-associated cardiac complications. By limiting the potential for subsequent clinical restenosis and reducing the need for bailout I stenting with its associated increased risk of major complications, t2,13 this strategy may help maxi- mize the potential clinical gains from a stent implanta- tion program in financially limited health care systems.

This report confirms the promising results of early case reports and small series describing stent implan- tation by the direct brachial approach. 6,7,9,t4 Although the number of patients enrolled in this study is too small to allow reliable statistical infer- ences to be drawn, the results are promising and suggest that elective coronary stents can be implant- ed by the direct brachial approach with a compara- ble success rate to that achieved with a percutaneous femoral approach.

The percutaneous femoral approach was associated with a major vascular complication rate of 5% in this study, undoubtedly related to the intensive anticoagu- lant regime used in the early phase of our stent implantation program. Closure of the arterial access site under direct vision facilitates hemostasis, and this limit- ed the major vascular complication rate to 1.4% in our brachial patients despite pretreatment with therapeutic levels of oral anticoagulants. In current clinical prac- tice, the combination of aspirin and ticlopidine without concurrent intensive anticoagulation is effective in pre- venting stent thrombosis and has greatly reduced bleeding complications associated with percutaneous access sites. 15 For many opera!ors, the percutaneous femoral route remains the chosen access site for the majority of stent implantation procedures. In patients with major peripheral vascular disease, however, access through the femoral artery may not be possible. In patients already receiving oral anticoagulants for other reasons (such as valvular heart disease or atrial

fibrillation), the risk of bleeding complications associat- ed with the percutaneous femoral approach may remain high. The results of our study indicate that elec- tive stents can be safely implanted in these circum- stances with the direct brachial approach with a low risk of major vascular complications.

Small-caliber (6F) guiding catheters with a large internal lumen have been developed in an attempt to limit vascular access site complications. These small- caliber guiding catheters facilitate the use of alterna- tive percutaneous vascular access site for coronary stenting. The radial artery is superficial and hemostasis can therefore be easily achieved by local compression. Recent reports indicate that the transradial approach is associated with success and complication rates for coronary stenting in anticoagulated patients compara- ble to our own results) 6 Although most PTCA and stent equipment is not 6F compatible, larger diameter catheters are required for some procedures. When an arm approach is necessary for atherectomy or the use of a larger-sized rotablator device, the direct brachial approach facilitates the introduction of appropriate- diameter guiding catheters. The direct left brachial approach with an arteriotomy and the percutaneous transradial approach are therefore complimentary and successful alternatives to a percutaneous transfemoml approach for coronary stenting; the particular approach chosen by an operator will depend on indi- vidual experience, personal preference, and equip- ment requirements.

Several important technical factors are relevant to the use of the direct brachial approach. The use of the left arm helps to optimize guiding catheter perfor- mance and may therefore be preferable to a right brachial approach. A left arm approach may not, how- ever, be feasible in some catheterization laboratories specifically designed for the femoral or right brachial approach where the physical limitations of the labora- tory setup may prevent the operators and monitors being moved to an appropriate position.

For experienced operators, there is no increase in radiation exposure, as confirmed by the similar fluo- roscopy times in our two groups. The use of an intro- ducer sheath inserted into the bmchial artery under direct vision minimizes the risk of subsequent arterial trauma during catheter exchanges and facilitates local hemostasis during the procedure. Excellent coaxial coronary intubation with good guiding catheter back- up and support is usually provided by the use of left Amplatz configuration guiding catheters for vein grafts

American Heart Journal Volume 134. Number& Parl 1

9 4 4 Nolan el al.

and right coronary lesions. When an Amplatz configu- ration guiding catheter is unsuitable for a native right coronary lesion, a right Judkins guiding catheter is usually appropriate and adequate. For left coronary lesions, Voda or Amplatz configuration guiding catheters are usually preferable to Judkins catheters.

In summary, we have demonstrated that a strategy of elective coronary stenting in angiographically unfavor- able coronary lesions is associated with a high degree of procedural success and a low overall complication rate. Coronary artery stenting is expensive, and many patients with ischemic heart disease will do well with conven- tional balloon angioplasty. Our strategy of electively stenting selected high-risk patients targets limited resources to those patients most likely to obtain clinical benefit from the procedure. The direct brachial approach allows percutaneous revascularization procedures to be safely and!successfully carried out in patients with severe peripheral vascular disease, even when large-caliber guiding ca!heters are required in anticoagulated patients.

We tha{lk airs. E. Batin, who compiled our stellt data- base; Dr. R. Stables, who provided advice on the use o f the Mine,va database and helped analyze the data; and airs. S. Rutter, who t)ped the manuscript.

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