Volume 66, Issue 2, Pages 203-205 (August 1974) Sudden, Severe Aortic Regurgitation: Reversal of the Abnormal Hemodynamics by Amyl Nitrite Inhalation  A.G. Adelman, M.D., E.D. Wigle, M.D., N. Ranganathan, M.B.B.S., W.G. Grant, M.D.  CHEST  Volume 66, Issue 2, Pages 203-205 (August 1974) DOI: 10.1378/chest.66.2.203 Copyright © 1974 The American College of Chest Physicians Terms and Conditions

FIGURE 1 Simultaneous left ventricular and aortic pressure recordings in sudden severe aortic regurgitation under control conditions (left) and following amyl nitrite inhalation (right). Note the equalization of left ventricular and aortic diastolic pressures at end-diastole in the control pressure recordings (left). The inhalation of amyl nitrite resulted in a reduction of left ventricular end-diastolic pressure (EDP) from 50 mm Hg to 27 mm Hg while aortic diastolic pressure was reduced from 50 mm Hg to 38 mm Hg. CHEST 1974 66, 203-205DOI: (10.1378/chest.66.2.203) Copyright © 1974 The American College of Chest Physicians Terms and Conditions

FIGURE 2 Simultaneous left ventricular and left atrial pressure recordings in sudden severe aortic regurgitation under control conditions (left) and following amyl nitrite inhalation (right). Note in the control situation (left) that left ventricular diastolic pressure exceeds left atrial pressure early in diastole, causing a reversed diastolic gradient across the mitral valve for the remainder of diastole. Following amyl nitrite inhalation there is a dramatic drop in left ventricular end-diastolic pressure (EDP) from 50 to 12 mm Hg and during the maximal amyl nitrite effect, left ventricular diastolic and left atrial pressures are equal, “a” = left atrial “a’ wave. CHEST 1974 66, 203-205DOI: (10.1378/chest.66.2.203) Copyright © 1974 The American College of Chest Physicians Terms and Conditions

FIGURE 3 Indicator dilution estimation of the degree of aortic regurgitation under control conditions (left) and following amyl nitrite inhalation (right). The dye curves were performed by injecting 2 ml of indocyanine green dye through the retrograde aortic catheter positioned 2 cm above the aortic valve during simultaneous sampling of blood from the left ventricle via the transseptal catheter. The time of injection of the green dye is indicated by the vertical arrow. The dye curves are inscribed from right to left, the initial downward deflection represents the regurgitant flow, while the second downward deflection in the dye curves indicates recirculating dye. Following inhalation of amyl nitrite there is a marked reduction in the degree of aortic regurgitation. The left ventricular end-diastolic pressure fell to 27 mm Hg and the aortic diastolic pressure to 34 mm Hg during the inscription of the dye curve. CHEST 1974 66, 203-205DOI: (10.1378/chest.66.2.203) Copyright © 1974 The American College of Chest Physicians Terms and Conditions