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Medical AI Inquiry: You was designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.  Labels: OBJECTIVE, METHODS, RESULTS. Meshes: Adult, Aged, Aged, 80 and over, Aorta, Blood Pressure, Cardiovascular Diseases, Compliance, Female, Humans, Infusions, Intravenous, Male, Middle Aged, Muscle, Skeletal, Nitroglycerin, Radial Artery, Vascular Resistance, Vasodilator Agents, Ventricular Function.
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Is benefit of glyceryl trinitrate on arterial stiffness directly due to effects on peripheral arteries? Context: To determine how the vasodilator glyceryl trinitrate (GTN) alters arterial stiffness and improves left ventricular afterload. Ascending aortic pressure waves were measured with fluid filled catheters of high fidelity in 50 patients undergoing cardiac surgery, before cardiopulmonary bypass, both before and after intravenous infusion of GTN. In all 50 patients, wave reflection was identifiable as a secondary boost to late systolic pressure, permitting the pressure wave to be separated into a primary component, attributable to left ventricular ejection and properties of the proximal aorta, and a secondary component, attributable to reflection of the primary wave from the peripheral vasculature. GTN infusion caused no change in amplitude of the primary wave (mean (SD) 0.0 (1.4) mm Hg, not significant) but substantial reduction (14.6 (9.6) mm Hg, p < 0.0001) in amplitude of the secondary reflected wave. Fall in mean pressure was attributable to a mix of arteriolar and venous dilatation, with relative contributions unable to be separated.
assistant
Favourable effects of GTN on arterial stiffness can be attributed to effects on peripheral muscular arteries, causing reduction in wave reflection. Results conform with previous invasive studies on vasodilator agents and their known effects on calibre and compliance of muscular arteries. Final Decision: yes