The Journal of thoracic and cardiovascular surgery
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J. Thorac. Cardiovasc. Surg. · Jan 1994
Randomized Controlled Trial Clinical TrialAllopurinol pretreatment improves postoperative recovery and reduces lipid peroxidation in patients undergoing coronary artery bypass grafting.
In this prospective, randomized, double-blind, placebo-controlled study, the clinical, biochemical, and hemodynamic effects of xanthine oxidase inhibition in patients undergoing coronary artery bypass grafting were assessed. Allopurinol pretreatment significantly reduced the use of inotropic support after the operation (5 of 25 patients versus 13 of 25 patients, p < 0.01) and increased the rate of peripheral warming (11.4 +/- 0.85 hours versus 14.4 +/- 1 hours, p < 0.02). Twenty patients (9 in the allopurinol group and 11 in the placebo group) underwent invasive hemodynamic monitoring and intraoperative coronary sinus cannulation. ⋯ Products of lipid peroxidation (thiobarbituric acid reactive substances) increased significantly in only the placebo group, with increases being evident both in the systemic circulation (9.5 +/- 3.2 nmol/gm albumin, p < 0.007, and 24 +/- 5 nmol/gm albumin, p < 0.001, at 30 seconds and 2 minutes of reperfusion, respectively) and the coronary sinus (19.4 +/- 5.8 nmol/gm albumin, p < 0.004, and 28 +/- 4 nmol/gm albumin, p < 0.001, at 2 and 5 minutes of reperfusion, respectively. No significant difference was evident between the groups with respect to cardiac enzyme or vitamin E release. It is proposed that xanthine oxidase inhibition exerts its beneficial effects by reducing the level of free radical activity associated with reperfusion during coronary artery bypass grafting.
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J. Thorac. Cardiovasc. Surg. · Jan 1994
Supravalvular aortic stenosis. Long-term results of surgical treatment.
To determine long-term outcome after operation for supravalvular aortic stenosis, we reviewed the case histories of 80 patients who had repair of the localized form (group A) (n = 67) or diffuse form (group B) (n = 13) from 1956 to 1992, including 31 patients with the Williams-Beuren syndrome. Ages ranged from 7 months to 54 years (mean = 12.6 years). Forty-six patients had one or more associated cardiovascular anomalies; the most common was aortic valve stenosis (33.8%). ⋯ By Cox multivariate model, the only independent predictor of late death for all patients was associated aortic valve disease (p = 0.02), which was also a risk factor for late reoperation (p = 0.02). In group B, overall survival was better in patients who received an extended patch versus aortic root patch only (p = 0.02). We reached the following conclusions: (1) Associated aortic valve disease was strongly correlated with late death and need for reoperation. (2) Both the teardrop-shaped and pantaloon-shaped patch techniques provide excellent long-term relief of localized supravalvular gradients and preservation of aortic valve competence. (3) In diffuse supravalvular aortic stenosis, aortic enlargement should be extended into the ascending aorta or beyond as required to relieve the gradient; some patients may require a graft or conduit.(ABSTRACT TRUNCATED AT 400 WORDS)
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J. Thorac. Cardiovasc. Surg. · Jan 1994
High-dose steroids prevent placental dysfunction after fetal cardiac bypass.
Surgical treatment of certain congenital heart lesions in utero may have a therapeutic advantage over postnatal repair or palliation. For fetal heart surgery to be possible, a method to support the fetal circulation is necessary. Early experimental attempts at fetal cardiac bypass were unsuccessful because of increased placental vascular resistance during and after fetal cardiac bypass, which led to decreased placental flow, fetal asphyxia, and death. ⋯ Placental blood flow and placental vascular resistance were calculated at four times during the experiments: before sternotomy; after sternotomy; during bypass at 30 minutes; and 30 minutes after cessation of bypass. Similar to indomethacin, high-dose steroid administration during fetal cardiac bypass prevents the rise in placental vascular resistance and preserves placental blood flow during and after fetal cardiac bypass. This study suggests that the production of a placental vasoconstrictive prostaglandin is responsible for the increase in placental vascular resistance and decrease in placental blood flow observed after fetal cardiac bypass.