Strategy to prevent nerve injury and deep vein thrombosis in radiofrequency segmental thermal ablation of the saphenous veins using a new objective pain scale.

OBJECTIVE: We evaluated the benefit of local anesthesia including tumescent anesthesia and active walking soon after surgery in preventing nerve injury and deep vein thrombosis caused during endovenous ablation. METHODS: Endovenous ablation was performed in 1334 consecutive patients. Varicectomy was performed using the stab avulsion technique. After surgery, patients were encouraged to walk 100-200 m inside the ward for 3-5 times/h. The pain was evaluated objectively using the Okamura pain scale and subjectively using the numerical rating scale. RESULTS: Stab avulsion was performed at 11.8 ± 8.0 sites and the mean operative time was 33.9 ± 15.2 min. The mean Okamura pain scale and numerical rating scale scores were 1.6 ± 1.3 and 3.0 ± 2.0, respectively. Deep vein thrombosis and pulmonary embolism were absent. The incidence of nerve injury was 0.3%. CONCLUSIONS: Endovenous ablation should be performed with the patients under local anesthesia to prevent nerve injury and deep vein thrombosis.

Topical application of a biodegradable disc with amiodarone for atrial fibrillation.

BACKGROUND: Amiodarone is a potent anti-atrial fibrillation (AF) agent; however, its systemic administration induces serious side effects such as interstitial pneumonia. To avoid such effects, we developed a local sustained-release system for amiodarone. METHODS: A biodegradable, cross-linkable dextran disc was developed as a sustained-release carrier for amiodarone. Under general anesthesia, Japanese white rabbits underwent median sternotomy and the biodegradable disc with or without amiodarone (30 mg) was implanted onto the surface of the right atrium. Three days after implantation, we measured tissue amiodarone concentrations (n = 5), the AF threshold, and the atrial effective refractory period of the left atrium by using the Langendorff apparatus. The incidences of induced AF evoked by rapid pacing were measured and compared. RESULTS: The right atrial concentration of amiodarone was far higher than that in the lungs, ventricles, or other organs (p < 0.01). The blood concentration of amiodarone was below detectable levels. The amiodarone biodegradable disc significantly increased the AF threshold (amiodarone group, 6.9 ± 4.6 mA versus control group, 0.5 ± 0.6 mA; p < 0.01) and the effective refractory period (amiodarone group, 53.9 ± 8.9 milliseconds versus control group, 43.9 ± 9.5 milliseconds; p = 0.035) of the left atrium, indicating the electrophysiologic effect of the amiodarone biodegradable disc on the left atrium. Further, the amiodarone group was significantly less likely to experience AF, as compared with the control group (p < 0.01). CONCLUSIONS: This approach may be a less invasive and effective therapeutic option for preventing postoperative AF.

Radial artery angiographic string sign: clinical consequences and the role of pharmacologic therapy.

BACKGROUND: The radial artery is an increasingly important graft for coronary artery bypass surgery. Postoperative angiographic studies have shown that a proportion of radial grafts become diffusely narrowed but not occluded, or string signs. METHODS: Four hundred forty patients receiving a radial artery graft enrolled in a large clinical trial underwent postoperative angiography at 1 year. Angiograms were analyzed visually and quantitatively. A complete string sign was defined as diffuse narrowing along the full length of the graft, while a partial string sign was defined as segmental narrowing. Angiographic findings were correlated with medication compliance and clinical sequelae. RESULTS: Thirty-one patients (7.0 %) had radial artery graft string signs versus 4 patients (0.9%) with a saphenous vein graft string sign (p = 0.001). Complete string signs were present in 28 cases, and the mean diameter was 0.76 +/- 0.14 mm (mean +/- SD), whereas 3 cases had a partial string sign with a diameter of 0.89 +/- 0.14 mm. Fifteen radial arteries showed Thrombolysis in Myocardial Infarction Study (TIMI) 1 flow, 3 cases showed TIMI 2 flow, and 13 cases showed TIMI 3 flow. There was no difference in incidence of radial string sign between patients taking nifedipine versus diltiazem postoperatively. Multivariate analysis revealed the presence of radial artery string sign was closely related to the perioperative use of alpha-adrenergic agonists and target vessels stenosis less than 90%. Postoperative symptoms were associated with radial artery string signs with TIMI 1 flow (p = 0.0045). CONCLUSIONS: In the Radial Artery Patency Study, radial artery string sign was present in 7% of patients. Despite diffuse narrowing, 52% of grafts had TIMI 2 flow or better.