Andrew D. Blann

Hemodynamic, hemostatic, and endothelial reactions to psychological and physical stress in coronary artery disease patients.

Episodes of psychological and physical stress may elicit thrombotic cardiac events, such as myocardial infarction. These events are triggered when there are concurrent hemodynamic, hemostatic, and endothelial abnormalities. Hemodynamic, hemostatic, and endothelial reactions of 72 (15 women, 57 men) coronary artery disease patients to psychological and physical stress were examined. Blood pressure, electrocardiography, and impedance cardiography were recorded during rest, mental arithmetic, and exercise. Blood was collected, via catheter, at rest and after each task. Mental arithmetic elicited increases in blood pressure, heart rate, cardiac output, and cardiac contractility, but no consistent changes in hemostatic and endothelial markers. In contrast, exercise, in addition to increasing blood pressure, heart rate, cardiac output, cardiac contractility, and lowering peripheral resistance, elicited increases in plasma viscosity, hematocrit, platelets, and tissue plasminogen activator together with a decrease in plasminogen activator inhibitor. This pattern of hemodynamic, hemostatic, and endothelial reactions suggests that acute psychological and physical stress influence the thrombotic system differently in these high risk patients. Future research is needed to investigate how these stress responses are prospectively related to acute cardiac events.

Atrial Fibrillation and Thromboembolism in Patients With Chronic Kidney Disease

A bidirectional relationship exists between atrial fibrillation (AF) and chronic renal disease. Patients with AF have a higher incidence of renal dysfunction, and the latter predisposes to incident AF. The coexistence of both conditions results in a higher risk for thromboembolic-related adverse events but a paradoxical increased hemorrhagic risk. Oral anticoagulants (both vitamin K antagonists [VKAs] and non-VKA oral anticoagulants [NOACs]) have been demonstrated to be effective inxa0mild to moderate renal dysfunction. Patients with severe renal impairment were excluded from the non-VKA oral anticoagulant trials, so limited data are available. In end-stage renal failure, the net clinical benefit of VKAs in dialysis-dependent patients remains uncertain, although some evidence suggests that such patients may do well with high-quality anticoagulation control. Risk stratification and careful follow-up of such patients are necessary to ensure a net clinical benefit from thromboprophylaxis.

A procoagulant state and endothelial dysfunction in obese children

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