The Canadian journal of cardiology
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Descending thoracic aortic surgery is linked to a high morbidity and mortality. Thoracic endovascular stent grafts were designed to decrease perioperative risks, especially in patients with severe comorbidities. However, procedure-related complications and clinical outcomes remain ill-defined. ⋯ Thoracic endovascular stent grafts show excellent early results in well-selected cases. Extra-anatomical bypass or novel vascular access procedures increase the applicability of thoracic endovascular stent grafts. Meticulous follow-up is essential to identify and treat stent graft-related complications. Data on long-term outcomes are required before applying thoracic endovascular stent grafts to patients with a lower operative risk.
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Comparative Study
Ventricular interaction during mechanical ventilation in closed-chest anesthetized dogs.
The cardiac effects of positive pressure ventilation and positive end-expiratory pressure are incompletely understood. External constraint due to increased intrathoracic pressure decreases left ventricular end-diastolic volume; the effects on venous return and ventricular interaction are less clear. Phasic changes in inferior vena caval flow, end-diastolic ventricular dimensions and output were measured in seven anesthetized, ventilated normal dogs. ⋯ In conclusion, positive pressure ventilation reduced right ventricular end-diastolic volume during inspiration and increased the transseptal pressure gradient, which shifted the septum rightward, increasing left ventricular end-diastolic volume and output. The reverse occurred during expiration. Positive end-expiratory pressure constrained left ventricular filling and decreased left ventricular end-diastolic volume further by a leftward septal shift.
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Early mortality following ST elevation myocardial infarction (MI) is declining in trial and nontrial settings. Absolute rates in nontrial settings remain significantly higher than those seen in randomized controlled trials. It is unclear if this mortality difference is due to different patient characteristics or to less frequent use of reperfusion strategies. ⋯ Mortality in ST elevation MI is disproportionately higher among patients who receive no reperfusion therapy. Many of these patients have clinical characteristics that may affect the physician's decision to provide reperfusion therapy. Improving overall survival among patients with ST elevation MI will be contingent on optimizing the number of patients receiving reperfusion therapy.