Valsalva Maneuver

VALSALVA MANEUVER (Valsalva), forced exhalation with the glottis closed after a very deep inspiration. The Valsalva maneuver demonstrates the effect of increased intrathoracic pressure on heart function. Valsalva proposed his experiment for studying the middle ear, in which exhalation was performed not with the glottis closed but with the nose and mouth closed by hand; when the eardrum is perforated and pus is present in the middle ear, it flows out through the opening in the eardrum. During deep inspiration, the blood flow to the heart increases, pressure in the aorta rises, and the pulse becomes slower; during exhalation with the glottis closed, due to increased intrathoracic pressure, venous return to the heart ceases, the neck veins become engorged, blood is squeezed from the pulmonary capillaries into the left heart, from which it is quickly expelled; the degree of filling of the heart cavities greatly decreases, the pulse becomes more frequent, becomes small or disappears altogether; after opening the glottis, return to normal. Changes in the cardiovascular system during the Valsalva maneuver have been studied comprehensively (X-ray, sphygmography, auscultation, etc.), and attempts have been made to use this maneuver for functional diagnosis of the heart.