International Journal of Cardiology. 18 (1988) 351-356 zyxwvutsrqponmlkjihgfedcbaZYXWVUTSRQPONMLKJIHG Elsevier 351 zyxwvutsrqponmlk IJC 00646 Valsalva maneuver: a test of the functional state of cardiac innervation in Chagasic myocarditis Abdel J. Fuenmayor, Leonardo Rodriguez, Argenis Torres, Jest Donis, Maria Navas, Abdel M. Fuenmayor and Diego Dhvila Departmento de Fisiologia y Centro de Investigaciones Cardiovasculares, Universidad de Los Andes, M&ida, Venezuela (Received 24 April 1987; revision accepted 3 September 1987) Fuenmayor AJ, Rodriguez L, Torres A, Donis J, Navas M, Fuenmayor AM, Dgvila D. Valsalva maneuver: a test of the functional state of cardiac innervation in Chagasic myocarditis. Int J Cardiol 1988;18:351-355. zyxwvutsrqponmlkjihgfedcbaZYXWVUTSRQPONML The ratio between maximal and minimal R-R intervals measured during the Valsalva maneuver is an adequate means of studying the functional state of the cardiac parasympathetic nervous system. We studied the changes in heart rate evoked during the Valsalva maneuver in 49 asymptomatic Chagasic patients with different degrees of myocardial involvement. The Chagasic patients were divided in three groups. Twelve patients had no evidence of heart disease except for an abnormal myocardial biopsy. Sixteen patients had a normal electrocardiogram hut revealed evidence of localized myocardial damage as shown by left ventricular cineangiogra- phy. Twenty-one patients had abnormal electrocardiograms and revealed multiple areas of abnormal left ventricular wall motion. The Valsalva ratio (mean f standard error) was 1.62 f 0.12 for controls, 1.52 f 0.10 for those with an abnormal biopsy, 1.48 f 0.06 for those with localized myocardial damage, and 1.31 f 0.04 for those with an abnormal electrocardiogram. There were no statistically significant dif- ferences between the control group (normal sero-negative subjects) and those patients with normal electrocardiograms. Results in those with an abnormal electrocardio- gram, however, were statistically different zyxwvutsrqponmlkjihgfedcbaZYXWVUTSRQPONMLKJIHG (P < 0.05) from the other groups. These results are in discordance with the commonly accepted hypothesis that cardiac parasympathetic denervation causes a dilated myocardiopathy in patients with chronic Chagasic myocarditis. Key words: Chagas; Valsalva maneuver; Parasympathetic denervation Correspondence to: Abdel J. Fuemnayor, Apartado Postal 154, M&da, 5101. Venezuela. 0167-5273/88/$03.50 0 1988 Elsevier Science Publishers B.V. (Biomedical Division)