Hemodynamic and anatomic factors affecting the frequency content of still's innocent murmur
1994; Elsevier BV; Volume: 74; Issue: 5 Linguagem: Inglês
10.1016/0002-9149(94)90917-2
ISSN1879-1913
AutoresRichard L. Donnerstein, Valerie S. Thomsen,
Tópico(s)Cardiovascular Health and Disease Prevention
ResumoS till’s innocent precordial murmur, also referred to as a vibratory or musical murmur, is found in many normal children and adolescents.’ The origin of this murmur has been attributed to vibrations of cardiac structures, turbulent blood flow, or minor pressure changes across normal valves.1-5 Still’s murmur has been associated with high aortic velocities4 and is accentuated by increased cardiac output. l4 This study evaluated the hemodynamic and anatomic factors associated with the frequency content of Still’s innocent murmur. Under a protocol approved by the institutional Human Subjects Committee, we evaluated 27 normal children (11 girls, 16 boys), aged 2.3 to 12.5 years (mean + SD 5.8 + 2.9) with no evidence of cardiac pathology and a Still’s murmur audible by auscultation. Aortic root diameter and left ventricular (LV) dimensions were measuredfrom parasternal M-mode recordings. Pulmonary artery diameter at the level of the valve annulus was measured from parasternal short-axis, 2-dimensional recordings. Ascending aortic velocities were measured by continuous-wave Doppler from the suprasternal notch and pulmonary velocities by pulsed Doppler from the parasternal short axis. Murmurs were detected, amplified, and analyzed using an MCG Spectra 3000 digital acoustic cardiography system (MCG International, New Haven, Connecticut). Murmurs were initially recorded on digital audio tape (model DTC-75ES, Sony Corporation, Tokyo, Japan) with the subject supine and resting quietly. Recorded murmurs later underwent 16-bit analog-to-digital conversion with real-time spec-
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