Routine Transradial Coronary Angiography in Unselected Patients
- Volume 17 - Issue 3 - March, 2005
- Posted on: 8/1/08
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Transfemoral coronary angiography is not always possible because of obstructive arterial disease, and following the procedure, hemostasis can be difficult to achieve. An alternative transradial procedure described by Campeau1 has been widely accepted both by operators and patients.2 Using 5 or 6 Fr catheters, it has even replaced the transfemoral approach as the routine method in some centers. The benefits of transradial angiography include immediate ambulation and a low risk of bleeding, hematoma, and pseudoaneurysm. However, it is technically more demanding, and thrombotic occlusion of the small radial artery occurs in 1–6% of the patients.2,3 Therefore, an abnormal modified Allen’s test, which indicates insufficient collateral capacity from the ulnar artery, is generally considered a contraindication to the transradial method. Relative contraindications are the need to visualize the contralateral internal mammary artery, and reduced renal function in order to keep the radial artery intact in the event of a subsequent need for a hemodialysis shunt.
We have performed transfemoral coronary angiography at Viborg Hospital since 1998. Patients in whom this approach was not possible had to be referred to Aarhus University Hospital in Skejby for a transbrachial or radial procedure. To avoid this, we decided to begin performing transradial angiography in 2001.
This paper describes the results obtained by a single operator during a learning phase of three months with selected patients, followed by a twelve-month period, with the intention to use the radial artery in all patients undergoing coronary angiography. Follow-up was performed 1.5–25 months after the procedure.
Material and Methods
Transradial coronary angiography was performed by one and the same operator (HB) during a 15-month period. The first three months constituted a learning period during which all 43 patients with stable angina pectoris referred to this operator were selected. Patients referred for all other indications underwent transfemoral angiography. In the following 12-month period, all 243 non-selected patients referred to the same operator were considered candidates for the transradial procedure. Only patients with an abnormal Allen’s test, those in whom there was a need to visualize the contralateral internal mammary artery, and those with renal disease were excluded. For 2 patients with suspected unstable angina who were not able to be stabilized and continued to experience chest pain on medical treatment, we chose the transfemoral route due to our experience with that technique and in order to minimize catheterization time. The results of 99 routine transfemoral angiographies in unselected patients were used as a comparison. These procedures were performed by the same operator in the 9-month period preceding transradial implementation.
After ensuring that there was acceptable ulnar blood supply to the entire hand (Allen’s test performed with pulse oxymeter), local subcutaneous anesthesia with 0.3–0.5 mL lidocaine 1% was administered. A small skin incision was made, and radial puncture was performed with a 21 gauge needle. A 0.021 inch soft-tipped straight wire was introduced. 5,000 U heparin was administered intravenously, followed by the insertion of a 6 Fr dilator and valved sheath.
To prevent spasm, 200 mg nitroglycerine and 5 mg verapamil were injected into the radial artery. Standard sheath length was 11 cm. During the learning phase, a few 6 Fr long sheaths (23 cm) were used, but were abandoned because of an increased tendency to spasm and pain at removal. A hydrophilic-coated 6 Fr, 13 cm sheath was used in 13 patients during the routine period. Coronary angiography and ventriculography were performed with 6 Fr catheters, introduced with ordinary J-shaped guidewires. If any obstruction was observed, the guidewire was replaced by a Road Runner (Terumo Medical Corp., Somerset, New Jersey) hydrophilic-coated, very soft-tipped one. If obstruction was still present, contrast was injected into the artery during fluoroscopy to visualize the cause. Standard catheter shapes were Judkins 3.5 for the left, and 4.0 for the right coronary artery, with other shapes used when needed. A pigtail catheter was used for ventriculography. Catheter time was measured from introduction to removal of the sheath. Furthermore, fluoroscopy time and contrast volume were recorded. At the end of the procedure, the arterial sheath was withdrawn and pressure over the puncture site was applied using a gauze dressing, a dorsally placed, padded metal splint, and a tourniquet. The patients were mobilized and the tourniquet was loosened after 1.5 hours and removed after 2 hours. Observation was continued for an additional 2 hours by the nursing staff before discharge.
Patients referred for a transradial procedure were seen at follow-up after 15 months (median; range: 1.5–25 months). They were questioned about complaints, the puncture site was examined, and sensitivity and motor functions of the arm and hand were evaluated. If a radial pulse could be palpated and the pulse oxymeter showed perfusion of the thumb during temporary occlusion of the ulnar artery, and no perfusion during temporary occlusion of both ulnar and radial arteries, the radial artery was considered open.
Statistical analysis. Continuous variables are presented as median (1st–3rd quartiles), and categorical values as percentages. The Mann-Whitney test was used for comparison of median values, and the Fisher exact test for categorical values.
Patient demographics are shown in Table 1. During the learning period, the 43 patients who were referred with stable angina pectoris were selected for a transradial approach. The success rate was 41/43 (95%). Of the two failures, one was due to radial artery spasm, and the other to the inability to cannulate the artery. No complications occurred.
In the routine period, 243 patients were referred for coronary angiography, 5.4% because of valvular disease. The other indications are shown in Table 2. Patients with unstable angina were stabilized with nitroglycerine infusion, aspirin, dalteparine and clopidogrel, and were free of symptoms and nitroglycerine for at least 24 hours before the examination. A primary transfemoral procedure was selected in 22 of the patients (9%). Thirteen patients had an abnormal Allen’s test (5.3%). Four had undergone a previous bypass operation with a left internal mammary artery (LIMA) graft, and surgeons ordered selective contrast injections into the right. Three patients had kidney disease and two had persistent unstable angina. The remaining 221 patients were selected for a transradial procedure. The success rate was 200/221 (90.5%), 91.0% for men and 86.5% for women, which were not different (p > 0.05). The reasons for failure were: inability to cannulate the radial artery (11 patients), radial artery spasm (6 patients), unsatisfactory catheter position (2 patients), and complications (2 patients). The complication rate was 6/221 (2.7%). Perforation of the brachial artery occurred in four patients, causing failure of the procedure in one. None of the perforations required treatment. Anaphylactic shock due to an unknown contrast allergy occurred in one patient and resulted in failure of the procedure. The patient was treated successfully. Finally, one patient developed myocardial infarction more than 24 hours after the procedure. No other types of complications occurred. In 14 patients (6.3%), the left radial artery was chosen because of a LIMA graft (5 patients), an abnormal right-sided Allen’s test (7 patients), and for undetermined reasons (2 patients).
The angiographies were evaluated when deciding the proper treatment at the reference center, and the image quality was found acceptable in all of the patients. Six patients underwent a successful repeat angiography through the same radial artery, 1 in the learning period, and 5 in the routine period. Out of 10 patients with a previous bypass operation, 9 had a successful angiography. One failed because of an inability to puncture the radial artery.
Catheter and X-ray times and contrast volume during the three periods are presented in Table 3. There were no differences in contrast volume. Catheter and X-ray times were significantly shorter in the routine period than in the learning period, but longer than in the preceding transfemoral period.
Follow-up. Of the 43 patients who underwent a transradial procedure during the learning phase, 3 had died and 1 did not show up. Four out of 39 patients (10.3%) had an occluded radial artery. Otherwise, no abnormalities were found and none of the patients had any complaints.
Of the 221 patients studied in the routine period, 13 had died (5.9%) and 16 did not respond to the follow-up request. Nine of the 192 patients who were seen at follow-up had an occluded radial artery (4.7%). This result is not significantly different from that of the learning phase (p = 0.25). None of the patients with an occluded artery had diabetes, and none had any complaints. The examination revealed no other pathological findings. In the group of 183 patients with with a non-occluded artery, 5 had experienced short-lasting pain/paresthesia in the arm or hand. One of these patients had a small probable pseudoaneurysm at the puncture site which did not require treatment. Another patient without any complaints had developed a small brachial artery aneurysm (see below). The others had no trophic or functional disturbances of the arm or hand. Five of the 6 patients who had undergone repeat angiography through the same radial artery were seen at follow-up. None of the arteries were occluded, but in one patient, a small aneurysm with no need of treatment was found on the brachial artery in the cubital fossa. Of the 4 patients who had perforation of the radial/brachial arteries, no one had complaints, but 1 had an occluded artery. No further abnormalities were found at follow-up in this group.
Two of 13 patients (15.4%) examined with a hydrophilic-coated sheath, and 7 out of 179 patients (3.9%) examined with a non-coated sheath had an occluded radial artery. The difference is not statistically significant (p = 0.11).
Six out of 178 successful procedures (3.4%), and 3 out of 14 unsuccessful procedures (21.4%), resulted in occlusion of the radial artery. These figures are significantly different (p = 0.02). In the group with a successful procedure, there was no relationship between catheter time and occlusion of the radial artery at follow-up.