Showing papers by "Sunnybrook Health Sciences Centre published in 2003"

Bivalirudin and Provisional Glycoprotein IIb/IIIa Blockade Compared With Heparin and Planned Glycoprotein IIb/IIIa Blockade During Percutaneous Coronary Intervention: REPLACE-2 Randomized Trial

Abstract: ContextThe direct thrombin inhibitor bivalirudin has been associated with better efficacy and less bleeding than heparin during coronary balloon angioplasty but has not been widely tested during contemporary percutaneous coronary intervention (PCI).ObjectiveTo determine the efficacy of bivalirudin, with glycoprotein IIb/IIIa (Gp IIb/IIIa) inhibition on a provisional basis for complications during PCI, compared with heparin plus planned Gp IIb/IIIa blockade with regard to protection from periprocedural ischemic and hemorrhagic complications.Design, Setting, and ParticipantsThe Randomized Evaluation in PCI Linking Angiomax to Reduced Clinical Events (REPLACE)–2 trial, a randomized, double-blind, active-controlled trial conducted among 6010 patients undergoing urgent or elective PCI at 233 community or referral hospitals in 9 countries from October 2001 through August 2002.InterventionsPatients were randomly assigned to receive intravenous bivalirudin (0.75-mg/kg bolus plus 1.75 mg/kg per hour for the duration of PCI), with provisional Gp IIb/IIIa inhibition (n = 2999), or heparin (65-U/kg bolus) with planned Gp IIb/IIIa inhibition (abciximab or eptifibatide) (n = 3011). Both groups received daily aspirin and a thienopyridine for at least 30 days after PCI.Main Outcome MeasuresThe primary composite end point was 30-day incidence of death, myocardial infarction, urgent repeat revascularization, or in-hospital major bleeding; the secondary composite end point was 30-day incidence of death, myocardial infarction, or urgent repeat revascularization.ResultsProvisional Gp IIb/IIIa blockade was administered to 7.2% of patients in the bivalirudin group. By 30 days, the primary composite end point had occurred among 9.2% of patients in the bivalirudin group vs 10.0% of patients in the heparin-plus-Gp IIb/IIIa group (odds ratio, 0.92; 95% confidence interval, 0.77-1.09; P = .32). The secondary composite end point occurred in 7.6% of patients in the bivalirudin vs 7.1% of patients in the heparin-plus-Gp IIb/IIIa groups (odds ratio, 1.09; 95% confidence interval 0.90-1.32; P = .40). Prespecified statistical criteria for noninferiority to heparin plus Gp IIb/IIIa were satisfied for both end points. In-hospital major bleeding rates were significantly reduced by bivalirudin (2.4% vs 4.1%; P<.001).ConclusionsBivalirudin with provisional Gp IIb/IIIa blockade is statistically not inferior to heparin plus planned Gp IIb/IIIa blockade during contemporary PCI with regard to suppression of acute ischemic end points and is associated with less bleeding.

Cutaneous angiosarcoma as a delayed complication of radiation therapy for carcinoma of the breast

Abstract: Three cases of cutaneous angiosarcoma of the breast that arose in irradiated skin tissue in women who had previously undergone treatment for breast carcinoma are reported. A review of the literature identified 55 cases of cutaneous angiosarcoma following radiation therapy as part of the treatment of carcinoma of the breast. For all 58 assembled cases, the mean age at the time of adjuvant radiation therapy for breast carcinoma was 64 years (range 42-83). The mean time to subsequent diagnosis in irradiated skin was 75 months (range 12-192). The estimated 3-year overall survival for all 58 patients was only 20%, similar to that of patients with the general form of angiosarcoma. Postirradiation angiosarcoma of the breast has a variety of presentations; thus diagnosis is often delayed. Early diagnosis relies on a high index of suspicion and appropriate histopathologic studies, as the clinical and histopathologic findings may be confused with other conditions. Treatment should be aggressive and include local surgery with consideration of adjuvant systemic chemotherapy.

Vasoproliferative tumours of the retina.

Abstract: This paper describes three cases of vasoproliferative tumours of the retina including histopathology in one. The clinical presentation, differential diagnosis and treatment modalities are discussed with a brief review of the literature.

Cell preparations comprising cells of the T cell lineage and methods of making and using them

Abstract: The invention relates to cell preparations comprising cells of the T cell lineage, methods for preparing same, and uses of the cell preparations

Comparison of methods to identify outliers observed in health services small area variation studies.

Abstract: Small area variation analysis (SAV) is an established methodology in health services and epidemiological research. The goal is to demonstrate that rates differ across areas, and to explain these differences by differences in physician practice styles or patient characteristics. While the SAV statistics provide an overall variation estimate, they do not provide a statistical means to identify significant outliers. We compared the chi-square (chi2) test with three approaches in determining significant outliers in SAV. We used data from the Canadian Institute for Health Information (CIHI) for Ontario residents discharged between 1989 and 1991. Coronary artery bypass surgery, hysterectomy and hip replacement data were used to compare four statistics in determining outliers: the chi2 test, Swift's approximate bootstrap confidence interval (ABC), Carriere's T2 (T2) with simultaneous confidence intervals (SCI), and Gentleman's normalized scores (GNS). Both the ABC and SCI correct the skewness of the distribution of the adjusted rates. With large data, confidence intervals calculated by the normal or the ABC methods are indistinguishable. The T2 can be applied to also nonbinary events. For binary events, it is asymptotically the same as the chi2. The GNS ranks the rates, but the distribution of these ranks does not differ significantly from that of the adjusted rates. We concluded that when using large data with binary events, there is little advantage in using the ABC, SCI or GNS over the commonly known chi2. The chi2 remains a useful tool in small area variation analysis to 'screen' or flag potential differences beyond chance alone.

Radiosensibilité et séquelles neurologiques tardives suite à la radiochirurgie de malformation artérioveineuse : la SF2 comme nouveau facteur prédictif

Abstract: Resume Objectif de l’etude. – Identifier la SF2 comme facteur pronostique des sequelles neurologiques dans le traitement des malformations arterioveineuses par la radiochirurgie. Patients et Methodes. – Cinq patients atteints de malformation arterioveineuse cerebrale (AVM), traites par radiochirurgie dans trois centres canadiens et ayant souffert de radionecrose cliniquement significative ont ete identifies. Leurs fibroblastes ont ete cultives, de meme que ceux de deux patients sans radionecrose apres une irradiation pour malformation arterioveineuse cerebrale et de cinq patients atteints de cancer sans complications et de cinq patients souffrant de complications apres une irradiation pour cancer. La radiosensibilite des fibroblastes de chaque patient a ete mesuree pour estimer la fraction de cellules survivantes a 2 Gy (SF2). Resultats . – Les patients avec sequelles avaient une SF2 differente de celle des 2 patients controles ainsi que de cinq patients cancereux controles sans radionecrose ( p = 0,005). Conclusion. – La radiochirurgie est un traitement electif des malformations arterioveineuses cerebrales et l’identification d’un sous-groupe de patients intrinsequement radiosensibles peut permettre d’eviter des sequelles neurologiques secondaires a la radiochirurgie, et ainsi ameliorer les resultats therapeutiques. La SF2 des fibroblastes constitue ainsi un nouveau modele predictif. Cette observation doit cependant etre confirmee dans un plus grand groupe de patients.

Graves' exophthalmos: Volumetric assessment of orbital expansion.

Abstract: The ophthalmopathy associated with Graves’ disease was first described in 1835 by an Irish physician, Robert J Graves. Its pathogenesis, however, remains uncertain. It is currently thought to be characterized by a chronic autoimmune process resulting in an infiltrative fibroblastic reaction involving all the periorbital soft tissues of both orbits. A commonly accepted hypothesis is that T cell lymphocytes react against thyroid follicular cells with shared antigenic epitopes in the retro-orbital space, initiating an inflammatory cytokine release (1). This in turn stimulates the synthesis of hydrophilic glycosaminoglycans (hyaluronic acid) by retro-orbital fibroblasts, and triggers the recruitment of new adipocytes from orbital adipose precursor cells. Ultimately, orbital soft tissue volume and osmotic load increase, leading to edema and fibrosis of involved tissues (2). The nature of the primary antigen(s) that is recognized by immunocompetent cells and autoantibodies has not been definitively determined. Potential antigens include the thyroid-stimulating hormone receptor protein and various extraocular muscle antigens (3). The ocular manifestations of Graves’ ophthalmopathy are variable, and occur concurrently with hyperthyroidism only 40% of the time. In fact, 20% of individuals with ophthalmopathy are noted to be euthyroid at time of presentation (4). Physical findings have been classified as infiltrative and noninfiltrative. The infiltrative changes are characterized by a lymphocytic infiltration of retro-orbital tissue and typically result in proptosis, extraocular muscle dysfunction and subsequent diplopia. In advanced cases, glaucoma from decreased episcleral venous outflow, or blindness secondary to compression neuropathy of the optic nerve may develop. The noninfiltrative changes are due to sympathetic hypertonia leading to spastic retraction of the eyelids, increase in palpebral fissure height, and subsequent risk of exposure keratopathy. These manifestations typically occur within 18 months of developing thyroid dysfunction. However, they may also precede or coincide with the systemic complications of dysthyroidism (5). The treatment of Graves’ ophthalmopathy primarily consists of nonsurgical therapy in the form of medications, such as steroids or immunosuppressants, or in selected cases, radio-therapy. Surgical therapy, often via multiple-staged procedures, is reserved for a minority (5%) of patients with severe exophthalmos. Indications for surgery may be cosmetic (ie, proptosis refractory to medical treatment) or functional. Functional indications for decompression include decreasing visual acuity, visual field defects, abnormal visual-evoked potentials, disc edema, as well as corneal exposure with keratitis refractory to medical management. In severe cases, the different aspects of Graves’ ophthalmopathy can be addressed by a combination of surgical techniques, including methods aimed at decreasing the soft tissue contents of the orbits or expanding the orbital bony volume. These include orbital lipectomy, two- and three-wall orbitotomies, and orbitozygomatic osteotomies (6–10). Ancillary measures such as lateral tarsorrhaphy and lid lengthening procedures are also often employed to decrease the risk of corneal exposure (11,12). To date, few studies have quantitatively examined the physical consequences of bony orbital expansion with respect to changes in ocular globe projection, and changes in the volume and distribution of orbital soft tissue contents. The present study is an initial investigation of the volumetric and morphological consequences of orbital osteotomy and expansion in patients with severe Graves’ exophthalmos.

Rectovaginal Fistulas and Intraoperative Bowel Injury

Abstract: A rectovaginal fistula is an abnormal epithelium-lined communication between the rectum and vagina. There is nothing more physically and psychologically disabling than the aura of the incontinence of gas and fecal matter. There still remains controversy as to the best primary surgical corrective technique but an even more challenging decision is the approach to the patient who has failed corrective surgery. What is the role of a defunctioning stoma and when should more advanced surgical techniques be used? This section of the chapter outlines a practical and scientific approach to answer these difficult and controversial questions.