Biomedical subjects

A Fortier

Publications and source records attributed to A Fortier.

12 recordsLinked to original sources

PubMed2006

Left ventricular end-diastolic pressure is a predictor of mortality in cardiac surgery independently of left ventricular ejection fraction.

BACKGROUND: Several risk factors have been shown to increase mortality in cardiac surgery. However, the importance of left ventricular end-diastolic pressure (LVEDP) as an independent risk factor before cardiac surgery is unclear. Method. This observational study investigated 3024 consecutive adult patients who underwent cardiac surgical procedures at the Montreal Heart Institute from 1996 to 2000. The primary outcome was in-hospital mortality with 99 deaths (3.3%) among these patients. RESULTS: Of the 35 variables subjected to univariate analysis, 23 demonstrated a significant association with mortality. Stepwise multivariate logistic regression identified LVEDP as an independent predictor of mortality after cardiac surgery. The area under the receiver operating characteristic curve of the model predicting mortality was 0.85. CONCLUSIONS: Elevated LVEDP is an independent predictor of mortality in cardiac surgery. This variable is independent of left ventricular ejection fraction.

Aged↗

PubMed2005

Influence of diabetes and bilateral internal thoracic artery grafts on long-term outcome for multivessel coronary artery bypass grafting.

OBJECTIVE: Diabetes mellitus is a major independent risk factor for morbidity and mortality after coronary artery bypass grafting (CABG). The aim of this study was to assess the effect of bilateral (B) internal thoracic artery grafting (ITA) in diabetic patients with multivessel CABG. METHODS: Between 1985 and 1995, 4382 patients underwent primary isolated multivessel CABG with ITA grafting and concomitant saphenous vein grafting (SVG). Outcome of diabetic and nondiabetic patients undergoing single (S) ITA+SVG (n=419 and 2079) and BITA+SVG (n=214 and 1594) grafting was obtained at a mean follow-up of 11+/-3 years. RESULTS: Diabetic patients were older, included more women, and had more obesity, hypertension and peripheral vascular disease than nondiabetic patients. Deep sternal wound infection rate was 1.9% for diabetic patients vs 1.2% for nondiabetic patients (P=0.2) and 30-day mortality was 1.7 vs 1.8% (P=0.9). Cox regression analysis with interaction term and propensity scoring showed that BITA grafting decreased the risk of death (Hazard Ratio=0.72 [0.57-0.91, 95%CI]) and coronary reoperation (HR=0.38 [0.19-0.77]) in both diabetic and nondiabetic patients, with no significant interaction noted. BITA grafting decreased the risk of myocardial infarction at long-term follow-up in nondiabetic patients (HR=0.72 [0.60-0.86]) but not in diabetic patients. Ten-year freedom rate from myocardial infarction in diabetic patients was 80 and 76% for SITA and BITA grafting patients, respectively. However, survival following myocardial infarction was better for patients who underwent BITA grafting, in both diabetic and nondiabetic subgroups. CONCLUSIONS: BITA+SVG grafting in diabetic patients improves survival and decrease coronary reoperation compared with SITA+SVG at long-term follow-up. Survival following myocardial infarction is improved with BITA grafting.

Age Factors↗

PubMed2004

Single versus bilateral internal thoracic artery grafts with concomitant saphenous vein grafts for multivessel coronary artery bypass grafting: effects on mortality and event-free survival.

BACKGROUND: The issue of superiority of single internal thoracic artery grafting versus bilateral internal thoracic artery grafting remains unresolved. The aim of this study was to compare the long-term outcome of single and bilateral internal thoracic artery grafting with concomitant saphenous vein grafting for multivessel coronary artery bypass grafting. METHODS: Between March 1985 and April 1995, 6650 patients underwent primary isolated coronary artery bypass grafting with internal thoracic artery grafts, including 4382 patients with multivessel bypass grafting requiring at least 3 grafts. Outcomes of patients undergoing single internal thoracic artery plus saphenous vein grafting (n = 2547) and bilateral internal thoracic artery plus saphenous vein grafting (n = 1835) were obtained at a mean follow-up of 11 +/- 3 years. RESULTS: Patients with bilateral internal thoracic artery grafting were younger, were mostly male, and had less diabetes, hypertension, unstable angina, and recent myocardial infarction than patients undergoing single internal thoracic artery grafting. Thirty-day mortality was 2.3% for the group undergoing single internal thoracic artery grafting versus 1.2% for those undergoing bilateral internal thoracic artery grafting (P =.007). Survival probability at 10 years was 88% for the single-graft group compared with 93% for the bilateral-graft group (P <.001). Multivariate analysis with propensity scoring showed that bilateral internal thoracic artery grafting decreased the risk of death (hazard ratio, 0.74; 95% confidence interval, 0.60-0.90), myocardial infarction (hazard ratio, 0.79; 95% confidence interval, 0.67-0.93), and coronary reoperation (hazard ratio, 0.41; 95% confidence interval, 0.21-0.80) throughout the follow-up period. Other significant predictors of death were diabetes, prior myocardial infarction, need for intra-aortic balloon pump, chronic heart failure, and peripheral vascular disease. CONCLUSION: Patients undergoing bilateral internal thoracic plus saphenous vein grafting appear to have a significantly better long-term clinical outcome than patients undergoing single internal thoracic artery plus saphenous vein grafting for multivessel coronary artery bypass grafting.

Coronary Artery Bypass↗

PubMed1995

Liposomal vaccines.

Liposomes have been used therapeutically to deliver drugs to certain anatomical sites. The use of liposomes to deliver antigens, although not a new concept, has received less attention. At least two vaccines of nearly identical liposome base composition to our vaccines have been tested in humans. A malaria vaccine study showed that the liposomal preparation is quite safe: reaction profiles of volunteers receiving the vaccine demonstrated little reactivity and virtually no pyrogenicity (14). The concentration of MPLA in the vaccine was substantially higher (nearly 50,000 times) than the pyrogenic dose of free lipid A. The same vaccine, but different antigen (gp120, an HIV protein), was tested in volunteers and had the same lack of toxicity (27). In both studies, antibodies and cytotoxic cells specific for the respective antigens were produced. We have several subunit vaccines under development for infectious diseases (gram negative sepsis, fungal infections, protozoan infections), metabolic disorders (hypercholesterolemia, diabetic retinopathy, macular degeneration), and neoplastic diseases (multi-drug resistant cancer, primary and metastatic tumors, and angiogenic hyperproliferative disorders). In each case, one or more antigens were identified that might be useful in immunologic control of biologic proliferation (i.e., pathogen or tumor growth, rise in serum cholesterol, growth of blood vessels). We anticipate that at least one of these vaccines will be ready for testing in humans in the next calendar year.

ATP Binding Cassette Transporter, Subfamily B, Mem↗

PubMed1995

Quantitative comparison of prone and supine myocardial SPECT MIBI images.

The myocardial count distribution and the stress/rest ratio distribution were compared between prone and supine Tc-99m MIBI myocardial SPECT acquisitions. Ninety-nine male patients with a low stress supine inferior wall count underwent stress and rest acquisitions in the supine and prone positions successively. For each study, values depicting the inferior, anterior, septal, and lateral wall counts were extracted from a medioventricular normalized circumferential profile and underwent a statistical analysis (Student's paired t-test). On prone imaging, when compared to supine imaging, counts showed a highly significant mean relative increase of 11% +/- 1% in the inferior wall and of 7% +/- 1% in the septum. Conversely, these counts showed a significant mean relative decrease of 4% +/- 1% in the anterior wall and of 3% +/- 1% in the lateral wall. Moreover, the inferior wall stress/rest ratio showed a highly significant mean relative increase (6% +/- 2%). The prone position is probably preferable for interpreting the inferior wall and septum, where relative counts are enhanced, as with TI-201, and because the inferior stress-rest discrepancies are reduced in that position. But the anterior and lateral wall information is impaired in the prone position. The authors suggest, in case of a low stress supine inferior count, the combination of both positions, which is feasible with Tc-99m MIBI, in order to prevent a misleading interpretation.

Adult↗

PubMed1994

Randomised comparison of amoxycillin and erythromycin in treatment of genital chlamydial infection in pregnancy.

Erythromycin, the standard treatment for chlamydial infection in pregnant women, commonly causes side-effects, which limits its efficacy. In a randomised, double-blind study, we compared amoxycillin with erythromycin in this setting. 210 pregnant women with Chlamydia trachomatis infection were randomly assigned 7 days' treatment with amoxycillin (500 mg three times daily) or erythromycin (500 mg four times daily). Control cultures were obtained 21 days after treatment, during late pregnancy, and from the infant within a week of birth. Treatment was judged a failure if any post-treatment culture was positive or if the patient had to stop therapy because of severe side-effects. 11 women (5.2%) were lost to follow-up. 1 (of 100) amoxycillin-treated women had to stop treatment because of severe side-effects compared with 12 (of 99) erythromycin-treated women (p = 0.002). 1 woman in the amoxycillin group had a positive culture at the third-trimester examination. No positive post-treatment culture was found in the erythromycin group. Severe gastrointestinal side-effects were more common in women who received erythromycin (31 vs 6%, p < 0.001). The overall failure rate was therefore 2% in the amoxycillin group and 12% in the erythromycin group (p = 0.005). These results suggest that amoxycillin is an acceptable alternative to erythromycin for C trachomatis infection in pregnant women.

Adult↗

PubMed1994

Reduced virulence of rifampicin-resistant mutants of Francisella tularensis.

Rifampicin-resistant mutants of a live vaccine strain (LVS) of Francisella tularensis were produced and screened for virulence in mice; 4 avirulent clones with intraperitoneal (ip) LD50s > 10(6) cfu, compared with 10(2) cfu for LVS, were characterized. Growth characteristics at 37 degrees C, surface envelope proteins, and lipopolysaccharide profiles of resistant mutants were identical to those of LVS. Polymerase activity of the mutants was more resistant than the enzyme from LVS to the inhibitory action of rifampicin. Growth rates for mutants and LVS were similar during the first 5 h at 42 degrees C, but viability of the mutants decreased to < 0.01% at 24 h. LVS and mutants differed in their ability to grow in vitro in host macrophages: LVS increased 580-fold over 72 h; mutants increased 33-fold. After ip inoculation of the organisms into mice, increasing numbers of LVS from peritoneal cells were isolated; mutants decreased over 4 days.

Animals↗

PubMed1992

Visualization of myocardial infarction 6 h after injection of 111In-antimyosin antibodies using a blood pool subtraction technique.

111In-antimyosin antibodies are capable of visualizing myocardial infarction (MI). Because of slow blood clearance, images are usually recorded 24 or 48 h postinjection. In this pilot study, a blood pool subtraction technique, which makes it possible to visualize MI 6 h postinjection, is validated. Twenty-five patients with proven MI (16 anterior, 9 inferior) were imaged a few minutes, 6 and 24 h after an injection of 111 MBq 111In-labelled antimyosin antibodies. Three planar views are obtained each time. Using software which performs the geometric registration, the grey level normalization and the subtraction of images, the blood pool image (obtained a few minutes postinjection) is subtracted from the 6 h image. The resulting image is the blood pool corrected 6 h image. The 24 h images and the blood pool corrected 6 h images were interpreted blindly and the number of correct, incorrect and impossible MI localizations was counted. The number of correct localizations is 19/25 for the standard 24 h images and 22/25 for the blood pool corrected 6 h images. Then, with this blood pool subtraction method, it is possible to visualize MI 6 h postinjection. This has to be taken into account when discussing the role of antimyosin scintigraphy in the management of patients with MI.

Antibodies, Monoclonal↗

PubMed1986

Comparison of phase analysis with factor analysis in equilibrium gated radionuclide angiography.

This study is the intercomparison of phase analysis (PA), factor analysis of dynamic structures (FADS) and Karhunen-Loeve analysis (KLA) in the diagnosis of regional wall motion abnormalities, RWMA, of the LV. One hundred and twenty eight patients with proven or suspected CAD have been investigated by both X-ray angiography and radionuclide equilibrium angiography performed in the LOA view. FADS and KLA are performed twice, once on the whole-image (WI-FADS, WI-KLA), and once on the LV ROI (LV-FADS, LV-KLA) as suggested by Pavel. Resulting images and factors are interpreted by a well trained observer. In an attempt to quantify LV-FADS images, two numeric parameters, P1 and P2, are defined. They measure the relative weight of the so-called ventricular factor for 2 and 3 factor analysis, respectively. A ROC curve is calculated for each method, taking X-ray angiography as the gold-standard. The areas under the ROC curves are estimated by the maximum likelihood method and are compared using a test described by Hanley which takes into account the correlation between the responses. The areas are: 0.90 for PA, 0.84 for WI-FADS, 0.86 for LV-FADS, 0.83 for WI-KLA, 0.86 for LV-KLA, 0.65 for P1 and 0.72 for P2. The observed differences are significant (at 5% level) between PA and WI-FADS and between FA and WI-KLA; whereas they are not between PA and LV-FADS, between PA and LV-KLA and between LV-FADS and LV-KLA. The diagnostic value of the two numeric parameters is poor.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1986

The objective evaluation of the phase image: a comparison of different automated methods.

One hundred and twenty eight patients with suspected or proven CAD were investigated using both X-ray ventriculography and equilibrium gated radionuclide angiography. In order to diagnose regional wall motion abnormalities, the parametric images obtained by Fourier analysis of the radionuclide images were analysed by different automated methods based on the measurement of the homogeneity of the phase values within the LV ROI. The effect of a diastolic frames exclusion, smoothing the original data, weighting the phase histogram, using Bacharach's error corrected phase distribution functions, using different descriptors of the spread of the phase histograms or distribution functions were tested. Using the results of the X-ray examination as the gold standard, ROC curves were plotted for each method. The ROC curves were modelled by a binormal model using the maximum likelihood method. Statistical tests were applied on the area under the ROC curves. The results show that the diagnostic value of the automated methods depends mainly on the way the histograms or distribution functions are described and to a lesser extent on the type of histograms or distribution functions used. The best result is obtained after smoothing, diastolic frames exclusion, weighting the phase histogram by the amplitude and describing it by its standard deviation. Nevertheless, this result is not significantly different from the result obtained by visual analysis of the phase and amplitude images.

Adult↗

PubMed1977

Epinephrine-induced cystoid macular edema in aphakic eyes.

A population of glaucomatous aphakic eyes being treated with topical epinephrine compounds was studied in order to determine the incidence of cystoid macular edema that had been induced by this medication. Eyes were considered responders only if fluorescein angiography demonstrated that macular edema was eliminated with discontinuation of epinephrine and recurred with reapplication of epinephrine. Reversible maculopathy occurred in six of 47 eyes. Topical epinephrine caused macular edema in an appreciable percentage of aphakic eyes, and we recommend that other medications be used to control glaucoma in aphakic patients when possible. If epinephrine compounds are required, periodic angiography is advisable.

Cataract Extraction↗

PubMedDate not supplied

[Peritoneal puncture dialysis in the monitoring and treatment of hemoperitoneum of traumatic origin?].

The great diversity of injuries after abdominal wound, need an adapted treatment. When laparotomy is indicated in uncontrollable hemorrhage, peritoneal lavage associated with C.T. scan seems to be interesting in the management of hemoperitoneum with a moderate injury severity score and stable arterial and venous pressures. Three patients were recently managed non operatively with good results. The authors draw up these three cases with inclusion criterias and limits of the method.

Abdominal Injuries↗