Left ventricular muscle volume in children and young adults

Abstract

A computer-assisted method of estimating left ventricular muscle volume and its clinical application in 193 children and young adults is described. Wall thickness was measured at the lower half of the left cardiac border in the angiographic posteroanterior projection of the left ventricle, where only three points are marked when the left ventricular contour is traced. The intra- and interobserver reproducibility of the wall thickness were both within 1 mm. The individual beat-to-beat variability was 0.6 mm, 10% of the mean thickness. In normal left ventricles, the ratio between ventricular muscle volume and end-diastolic volume, the muscle volume index (MVI), was independent of body surface area, being 1.01 + 0.14 (mean +/- SD, n = 28). MVI was normal in ventricles which were volume loaded secondary to a ventricular septal defect (n = 9) or ductus arteriosus (n = 11). It was significantly increased in aortic coarctation (1.66 +/- 0.44, n = 24, P less than 0.001) and in valvar aortic stenosis (1.34 +/- 0.31, n = 21, P less than 0.01). In tetralogy of Fallot (n = 34) MVI was normal. MVI was significantly reduced in the case of pressure and possibly volume-underloaded left ventricles of simple transposition of the great arteries (TGA) (0.53 +/- 0.15, n = 15) at the age of one year, compared to normal (P less than 0.001) and to the mean in TGA shortly after birth (P less than 0.05). However, it increased (P less than 0.001) to normal after banding of the pulmonary artery in TGA.

Angiographic Determination of Left and Right Ventricular Volumes and Left Ventricular Mass in Normal Infants and Children.

“…This finding represents that LV mass develops more rapidly than BSA during pediatric age group as observed in LVEDV and RVEDV. Similar results were presented by Nakano (1977) and Onnasch et al (1984). In contrast, Graham et al (1971) reported that there was a linear relationship between LV mass and BSA.…”

“…In contrast, Nakano (1977) documented that LV mass/LVEDV was nearly constant regardless of age. Onnasch et al (1984) also reported this parameter to be independent of BSA. Our results support these observations.…”

“…To the best of our knowledge, no normative value of LV volume calculated by the Simpson's rule method have been documented in the pediatric population. Although angiographic determination of LV mass was conventionally performed using the method published by Rackley et al (1964), limited studies concerning normative values of it have been reported during pediatric age group (Graham et al 1971;Nakano 1977;Onnasch et al 1984). The purpose of the present study is, therefore, to provide normative values of LV and RV volumes calculated with the Simpson's rule method, and LV mass through a wide range of body surface area (BSA) in a large number of infants and children.…”

Response of the right ventricle to progressive pressure loading in pigs

“…End-diastolic and end-systolic contours of these projections were manually marked with an x/y coder and stored in a computer (8,24). End-diastolic (EDV) and endsystolic (ESV) volumes were calculated with the multiple slices method, using correction factors appropriate for spatial orientation and cardiac phase (13,16).…”

Theoretical and empirical derivation of cardiovascular allometric relationships in children

“…Despite the physiological and clinical importance of the issue, the best means by which to adjust for the impact of body size on the size of cardiovascular structures remains controversial. Numerous studies (14,17,24,28,31,36,50,52,55,58,68,69) have addressed this issue but have reached different and therefore suspect conclusions. Nearly all have relied on simple regression analysis without a firm theoretical basis (1).…”