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Introduction: Challenges remain in predicting mortality and severe myocardial dysfunction in patients undergoing primary percutaneous coronary intervention (PPCI) for ST elevation myocardial infarction (STEMI).

Areas covered: Cardiogenic shock is associated with a high mortality rate. Less well characterized are patients who are not in cardiogenic shock but will die from pump failure as a result of a STEMI. There is a long history of using hemodynamics to risk stratify patients with acute MI with the Killip class being shown to provide prognostic information in the prereperfusion, thrombolytic and PPCI eras. Recent studies have identified low systolic blood pressure (SBP), elevated heart rate, elevated left ventricular end diastolic pressure (LVEDP), and low SBP/LVEDP ratio as hemodynamic parameters associated with early mortality in patients undergoing PPCI. Although infrequently used, prognostic information can be obtained from right heart catheterization in the setting of STEMI with the best-studied parameters being cardiac power, pulmonary capillary wedge pressure (PCWP), cardiac output, right atrial pressure/PCWP ratio, and pulmonary artery pulsatility index.

Expert commentary: Hemodynamic parameters measured at the time of PPCI provide important prognostic information. Whether hemodynamics can be used to determine which patients benefit from early initiation of mechanical support remains to be determined.  相似文献   

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PURPOSE: To examine the feasibility of a direct videoscopic approach to the descending thoracic aorta for endograft delivery to the aortic arch. METHODS: A double purse-string suture was placed on the aorta of 3 pigs via a thoracoscopic approach. Subsequently, the aorta was cannulated in the center of the purse-string. A 22-F delivery catheter was advanced under fluoroscopic control over a guidewire via a trocar into the proximal aorta. After deployment of a tubular endograft, the catheter was withdrawn from the aorta while simultaneously tightening the purse-string suture, without aortic cross clamping. The outcome was evaluated by post implant angiography and autopsy results. RESULTS: The procedure was successfully completed in all animals, with a mean total procedure time of 126 minutes (range 118-137). Mean endograft implantation time from needle puncture to catheter extraction was 27 minutes (range 21-37). Hemostasis was obtained in all animals after withdrawal of the delivery catheter and tightening the purse-string suture. The mean blood loss was 143 mL (range 80-220). Autopsy proved all purse-string sutures to be adequately placed and all endografts deployed in the correct position. CONCLUSION: A direct videoscopic approach to the descending thoracic aorta proved a feasible technique for endograft delivery to the aortic arch in a porcine model.  相似文献   
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Described here is a case of multiple myeloma in a patient with sickle cell anemia. Viscometric studies were made by comparing the patient's whole blood, plasma and washed red blood cells with those of a normal control subject and a patient with sickle cell anemia. Results showed that the increased viscosity of the patient's whole blood as compared with that of the control patient with sickle cell anemia was mainly due to erythrocytic Interaction with the circulating abnormal immunoglobulin. It is postulated that the increased frequency of vaso-occlusive crisis that occurred in our patient in the months before the diagnosis and treatment of multiple myeloma, was due to this cell-protein interaction with the resulting enhancement of whole blood viscosity and the sickling phenomena.  相似文献   
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The in vitro steroidogenic capacity of the gonadal tissue in the protandrous Rhabdosargus sarba was studied. Testicular and ovarian tissues from various sexual phases were used either separately or combined. With progesterone as precursor, high yield of 5 beta-reduced metabolites, and no 11-ketotestosterone or 11 beta-hydroxytestosterone were found. The production of 5 beta-pregnan-3 alpha-ol-20-one and 5 beta-pregnane-3,20-dione was very high in incubations with testicular tissue from intersexes or males and was low in those with ovarian tissue only. The production of 17 alpha-hydroxyprogesterone was high in the female but was low in other sexual phases. With testosterone as precursor, 11-ketotestoterone and 11 beta-hydroxytestosterone were identified. The latter was the most abundant and prominent polar steroid in all incubations. 5 beta-Reductase activity was high in the male and relatively low in the female. 5 alpha-Reduced products, however, were absent. There was an increase in the production of androstenedione as the animal underwent sex reversal. The significance of this change in steroidogenesis in this protandrous fish is at present under investigation. Experimental results also indicated that in the intersexual gonad there may be interaction between the testicular component and the ovarian component in steroidgenesis.  相似文献   
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BackgroundTools for advance care planning (ACP) are advocated to help ensure patient values guide healthcare decisions. Evaluation of the effect of tools introduced to patients in clinical settings is needed.ObjectiveTo evaluate the effect of the Canadian Speak Up Campaign tools on engagement in advance care planning (ACP), with patients attending outpatient clinics.Patient involvement: Patients were not involved in the problem definition or solution selection in this study but members of the public were involved in development of tools. The measurement of impacts involved patients.MethodsThis was a prospective pre-post study in 15 primary care and two outpatient cancer clinics. The outcome was scores on an Advance Care Planning Engagement Survey measuring Behavior Change Process on 5-point scales and Actions (0?21-point scale) administered before and six weeks after using a tool, with reminders at two or four weeks.Results177 of 220 patients (81%) completed the study (mean 68 years of age, 16% had cancer). Mean Behavior Change Process scores were 2.9 at baseline and 3.5 at follow-up (mean change 0.6, 95% confidence interval 0.5 to 0.7; large effect size of 0.8). Mean Action Measure score was 3.7 at baseline and 4.8 at follow-up (mean change 1.1, 95% confidence interval 0.6–1.5; small effect size of 0.2).Practical valuePublicly available ACP tools may have utility in clinical settings to initiate ACP among patients. More time and motivation may be required to stimulate changes in patient behaviors related to ACP.  相似文献   
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ObjectiveBilateral oophorectomy leads to reduced bone mineral density (BMD), and reduced BMD is associated with increased marrow fat and reduced marrow perfusion. Purpose of this study was to investigate how soon these changes occur following surgical oophorectomy.ResultsReduced BMD, increased marrow FF, and reduced marrow perfusion occurred synchronously post-oophorectomy. There was a sharp decrease of 12.5 ± 7.2% in BMD (n = 6), a sharp increase of 92.2 ± 46.3% (n = 6) in FF, a sharp decrease of 23.6 ± 3.9% in maximum contrast enhancement (n = 5), and of 45.4 ± 7.7% for enhancement slope (n = 5) during the initial 3 months post surgery. BMD and marrow perfusion continued to decrease, and marrow FF continued to increase at a slower rate during the following 18 months. Friedman test showed a significant trend for these changes (p < 0.05).ConclusionBilateral oophorectomy leads to a rapid decrease in lumbar BMD, an increase in marrow fat content, and a decrease in marrow blood perfusion.  相似文献   
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