Background. The goal of this retrospective cohort study (REVATA) was to determine the site, source, and contributory factors of varicose vein recurrence after radiofrequency (RF) and laser ablation. Methods. Seven centers enrolled patients into the study over a 1-year period. All patients underwent previous thermal ablation of the great saphenous vein (GSV), small saphenous vein (SSV), or anterior accessory great saphenous vein (AAGSV). From a specific designed study tool, the etiology of recurrence was identified. Results. 2,380 patients were evaluated during this time frame. A total of 164 patients had varicose vein recurrence at a median of 3 years. GSV ablation was the initial treatment in 159 patients (RF: 33, laser: 126, 52 of these patients had either SSV or AAGSV ablation concurrently). Total or partial GSV recanalization occurred in 47 patients. New AAGSV reflux occurred in 40 patients, and new SSV reflux occurred in 24 patients. Perforator pathology was present in 64% of patients. Conclusion. Recurrence of varicose veins occurred at a median of 3 years after procedure. The four most important factors associated with recurrent veins included perforating veins, recanalized GSV, new AAGSV reflux, and new SSV reflux in decreasing frequency. Patients who underwent RF treatment had a statistically higher rate of recanalization than those treated with laser.
Heterotopic prosthetic ventricles were used to support the circulation in 29 candidates for heart transplantation who were expected to die before procurement of a donor heart. Twenty-one of these patients (average age, 36 years) underwent successful transplantation after 8 hours to 31 days of circulatory support. The other eight patients died because their condition could not be stabilized for transplantation, despite restoration of blood flow. Fourteen patients received biventricular support; 15 received only left ventricular support, with pharmacologic assistance of right heart function. Before transplantation, blood flow from the left prosthetic ventricle averaged 2.8 +/- 0.4 liters per minute per square meter of body-surface area, and from the right prosthesis 2.4 +/- 0.4 liters, as compared with an average flow of 1.6 +/- 0.5 liters per minute per square meter before implantation. Of the 21 patients who received heart transplants, 20 were discharged from the hospital after a median of 31 days. Nineteen patients were alive at 7 to 39 months, and 11 of the first 12 were alive at one year. We conclude that heterotopic placement of prosthetic ventricles as a bridge to transplantation provides an effective method of temporarily supporting cardiac function in critically ill patients without removing the natural heart. The early survival rate after transplantation is similar to that with elective cardiac transplantation.
Methylene blue is occasionally applied to the adventitia of blood vessels during coronary artery bypass and other vascular procedures to assist in the orientation of the vessel. Inherent in this method is the assumption that extravascular application of methylene blue is innocuous with regard to vascular function. In the first part of this study, the in vitro vascular reactivity of methylene blue-labeled saphenous veins was compared with that of veins that were not marked with methylene blue. The vasoactive agents tested were designed to examine multiple pathways. They included potassium chloride, prostaglandin F2 alpha, phenylephrine, serotonin, angiotensin II, BHT-933 (alpha 2-adrenergic agonist), sodium nitroprusside, acetylcholine, isoproterenol, and verapamil. Compared with unmarked veins, those marked with methylene blue demonstrated a significant impairment of both vasoconstrictor and vasodilator function. These observations were made on a relatively small number of patients and could therefore be attributed to inherent differences between patients or surgical procedures. In the second part of this study, these variables were eliminated by dividing a single vein from one patient into three segments for a 45-minute exposure to external only methylene blue, internal and external methylene blue, or no methylene blue. The segments were then evaluated for vasoreactivity in vitro. Externally applied methylene blue reduced vasoconstriction regardless of the agonist. Further, both endothelium-dependent and -independent vasodilation was diminished by external methylene blue exposure. In veins exposed to methylene blue both internally and externally the results were similar but the magnitude of impairment greater. It is concluded that surgical marking of blood vessels with methylene blue has the potential to adversely affect vascular reactivity and therefore the use of alternative dyes should be considered.
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