The efficacy of warfarin-induced anticoagulation in reducing radial artery occlusion (RAO) after transradial access is not known. The present case-control study compared the incidence of early (24 hours) and late (30 days) RAO in patients undergoing transradial diagnostic coronary angiography during therapeutic warfarin anticoagulation (group 1) with that of a matched (3:1) cohort of patients not receiving warfarin and receiving intraprocedural heparin (group 2). All patients underwent transradial diagnostic coronary angiography using a 5F hydrophilic introducer sheath. The patients in group 2 received an intravenous heparin bolus (50 IU/kg) immediately after sheath insertion. After sheath removal, hemostasis was obtained using the TR-band (Terumo Interventional Systems, Terumo Medical, Tokyo, Japan) and a plethysmography-guided patent hemostasis technique. We included 86 patients receiving warfarin with an international normalized ratio of 2 to 4 in group 1 and 250 matched patients in group 2. No significant differences were present in the demographic and procedural variables between the 2 groups. Early RAO occurred in 18.6% of the patients in group 1 compared with 9.6% of patients in group 2 (p = 0.024). The incidence of late RAO remained significantly higher in group 1 compared with group 2 (13.9% vs 5.2%, p = 0.01). All patients with RAO remained asymptomatic. In conclusion, patients receiving chronic oral anticoagulation with warfarin and undergoing transradial coronary angiography without parenteral anticoagulation had a higher incidence of early and late RAO compared with patients receiving standard intravenous heparin therapy.
The transradial approach (TRA) for coronary and peripheral vascular procedures has gained greater acceptance owing to increased patient comfort, lower access site bleeding complications, and lower cost. The TRA is especially well suited for patients receiving long-term oral anticoagulant therapy using warfarin, when the interruption of warfarin therapy is not optimal or desirable. Radial artery occlusion (RAO) is a consequence of TRA, with a reported incidence of 1% to 10%. Intraprocedural administration of parenteral anticoagulants, including unfractionated heparin, enoxaparin, and bivalirudin, have been found to significantly decrease the incidence of RAO. This appears to be a dose-dependent and systemically driven effect. Because of the efficacy of these parenteral anticoagulants in preventing RAO, it would be intuitive to expect a therapeutically anticoagulated state from warfarin therapy to have similar efficacy in preventing RAO after TRA. However, few data are available on the incidence of RAO in long-term anticoagulated patients undergoing TRA diagnostic coronary angiography. We sought to evaluate the incidence of RAO in patients receiving therapeutic systemic anticoagulation using warfarin, who were undergoing coronary angiography using TRA, and to compare its efficacy with that in a matched cohort of patients in the same period, who were not receiving long-term oral anticoagulation but treatment with standard intraprocedural unfractionated heparin.
Methods
We included patients referred for cardiac catheterization from our registry from January 2009 to December 2011 at 2 community hospitals in Pennsylvania, who were undergoing TRA diagnostic coronary angiography and receiving uninterrupted long-term oral systemic anticoagulation therapy with an international normalized ratio on the day of the procedure of 2.0 to 4.0 (group 1). A 3:1 matched cohort of patients who had undergone TRA diagnostic coronary angiography during the same period at the same institution, who were not receiving long-term systemic anticoagulation therapy, served as the control group (group 2). A larger cohort of patients not receiving warfarin was included because of the expected much lower incidence of RAO. All patients provided written informed consent for the procedure, and the institutional review board authorized the release of information after review. The demographic and procedural data were collected for all patients.
Radial artery access was obtained in a standard fashion, with sterile preparation and local anesthetic infiltration using 1% preservative-free lidocaine. A 20-gauge Teflon-sheathed angiocatheter-like needle was used to puncture the radial artery using a counter-puncture technique, and a 5F hydrophilic-coated introducer sheath (Radiofocus introducer, Terumo Medical, Tokyo, Japan) was placed over a 0.21-in. straight-tipped stainless steel guidewire into the radial artery lumen. A vasodilator “cocktail” consisting of 200 μg of nitroglycerin and 5 mg of diltaizem was administered intra-arterially in the introducer sheath to all patients in both groups. The patients in group 1 did not receive additional parenteral anticoagulation. All the patients in group 2 received 50 U/kg unfractionated heparin administered intravenously after placement of the introducer sheath in the radial artery. Warfarin therapy was not interrupted in any of the group I patients Coronary angiography was performed using 5F standard angiographic catheters.
All patients received hemostasis, after removal of introducer sheath, using an inflatable band (TR band, Terumo Medical), applied at the access site, in accordance with the patent hemostasis protocol. The compression was maintained for 2 hours in all patients, with monitoring of patency of the radial artery every 15 minutes. After removal of the band, the patients were monitored for 30 minutes, a light noncompressive dressing was applied at the access site, and the patients were discharged using the standard protocol.
Radial artery patency was evaluated using a plethysmographic monitor to detect perfusion in the index finger. The plethysmographic monitor was placed on the index finger, and the radial and ulnar arteries were occluded manually at the level of the wrist joint. Maintaining occlusive compression of the ulnar artery, the radial artery was released, and the plethysmographic signal was observed. Return of the pulsatile plethysmographic signal was deemed consistent with radial artery patency. All patients with absence of radial artery patency were evaluated using duplex ultrasonography. RAO detected at 24 hours after the procedure was termed early RAO, and that detected at the 30-day follow-up examination was termed late RAO. Radial artery patency or occlusion data were recorded for all patients at 24 hours and 30 days after the index procedure. Hematomas were categorized using the Early dischArge after transradial Stenting of coronarY arteries (EASY) study hematoma scale.
Patients from group 2 were matched to patients from group 1 for age, gender, body mass index, and cardiovascular risk factors. Categorical variables are expressed as numbers and percentages and continuous variables as mean ± SD. Numerical variables were compared using Student’s t test and categorical variables using chi-square analysis. Statistical analysis was performed using the Statistical Package for Social Sciences, version 17.0 (SPSS, Chicago, Illinois). A p value <0.05 was considered significant.
Results
The data from 336 patients referred for cardiac catheterization who had undergone diagnostic coronary angiography were analyzed. Group 1 consisted of 86 patients who were treated with warfarin with an international normalized ratio on the day of the procedure of 2.0 to 4.0. Group 2 consisted of 250 consecutive patients who had undergone transradial coronary angiography in the same period at the same institution but who had not been receiving oral anticoagulant therapy. Three patients receiving warfarin therapy were excluded from the analysis because of systemic anticoagulation administered during the procedure for urgent or emergent percutaneous coronary intervention. The baseline characteristics and procedural variables are listed in Table 1 . No significant differences were observed between the 2 groups.
| Variable | Warfarin Group (n = 86) | Heparin Group (n = 250) | p Value |
|---|---|---|---|
| Age (yrs) | 72 ± 9 | 72 ± 11 | 0.928 |
| Men | 62 | 66 | 0.295 |
| Hypertension treated | 72 | 72 | 0.554 |
| Diabetes mellitus treated | 45 | 38 | 0.142 |
| Dyslipidemia treated | 62 | 53 | 0.12 |
| Current smoker | 35 | 42 | 0.44 |
| Body mass index (kg/m 2 ) | 25 ± 5 | 30 ± 5 | 0.243 |
| Serum creatinine (mg/dl) | 1.1 ± 0.3 | 1.1 ± 0.72 | 0.759 |
| Heparin dose (U) | 0 | 4,347 ± 873 | 0.0001 |
| International normalized ratio | 2.6 ± 0.4 | 1.3 ± 0.3 | 0.01 |
| Patients taking aspirin | 35 (41) | 118 (47) | 0.18 |
| Patients taking clopidogrel | 14 (16) | 49 (20) | 0.31 |
| Dual antiplatelet therapy | 4 (5) | 18 (7) | 0.3 |
| Procedure time (min) | 6 ± 2 | 6 ± 3 | 0.22 |
Stay updated, free articles. Join our Telegram channel
Full access? Get Clinical Tree
