Position of the apex beat in childhood, Schemes and Mind Maps of Cardiology

Download Position of the apex beat in childhood and more Schemes and Mind Maps Cardiology in PDF only on Docsity! Archives of Disease in Childhood, 1978, 53, 585-589 Position of the apex beat in childhood ASUQUO U. ANTIA, STEFAN R. MAXWELL, ALIGH GOUGH, AND 0. AYENI From the Department ofPaediatrics, University of the West Indies, Mona, Kingston, Jamaica, and Department ofPreventive and Social Medicine, University of Ibadan, Nigeria SUMMARY The position of the apex beat in relation to the midclavicular and nipple lines and the intercostal spaces was studied in 353 healthy Jamaican children from birth to 10 years. The traditional use of the midclavicular line as a reference point in relation to the apex beat is not an accurate index of normal heart size at all ages. For this purpose actual measurement of the apex beat, which ranges between 2 - 8 and 5 *4 cm from the midline, should be made. However, for a rough estimate of normal cardiac size the midclavicular line may be used. In contrast, the nipple line lies outside the apex beat at all ages; it should not be used in the clinical evaluation of normal cardiac size. From birth to age 3 years the apex beat is located in the 4th intercostal space and with increasing age gradually moves into the 5th space in most children. In clinical practice the intercostal space (ICS), the midclavicular line (MCL), and sometimes the nipple line (NPL) are used as reference points to assess the position of the apex beat (AB). While some authors (White, 1951; Dammann, 1959) state that the AB in normal children of all ages is in the fourth left intercostal space (4LICS), others (Julian, 1970; Julian and Turner, 1974) assert that irrespective of age the AB is usually in the fifth space (5LICS). With regard to the relationship of the AB to the mid- clavicular line (MCL), White (1951) states that in children of all ages it is normally beyond this line. In contrast, Julian (1970), and Julian and Turner (1974) have reported that the AB is at or within the MCL. These assertions may be correct as far as they concern adults as all the authors, except Dammann, are eminent cardiologists who deal primarily with adults. The only other reference to the normal AB in childhood is by Kaplan (1975), who states that the AB is in the 4LICS from birth to age 2 years and thereafter is in the 5LICS. It is also noteworthy that no standard textbooks on paediatric cardiology (Taussig, 1960; Nadas, 1963; Keith et al., 1967; Watson, 1968) attempt to define the position of AB in normal children. In view of the above seemingly contradictory statements the present study was undertaken to evaluate clinically the AB in relation to the MCL, NPL, ICS, and chest circumference in normal children of different ages. Received 9 January 1978 Subjects and methods The subjects consisted of healthy Jamaican children selected from among (a) newborn babies in the obstetric wards, and also those attending the infant welfare clinic, University College Hospital of the West Indies, Kingston, (b) children attending day- care nurseries, and (c) children attending the Mona Primary School and the Hope Valley experimental School in Kingston, Jamaica. The children were selected after appropriate clinical examination to exclude cardiorespiratory disorders and chest deformities. Any child with a cardiac murmur was excluded even if it was thought to be an innocent murmur. Similarly children with any degree of respiratory disorder were excluded. The AB, defined as 'the furthermost point of visible cardiac pulsation in the praecordium down- wards and to the left at which the finger is distinctly lifted' (Julian and Turner, 1974), was determined in the erect position in children aged between one and 3 years, in the supine position in the newborn babies, and in both the erect and supine positions in the others. The AB was evaluated in each child inde- pendently by 3 investigators. Before the study started each investigator had examined several normal children of different ages to ensure there was close agreement on the methodology. In adopting this procedure the investigators were satisfied that observer errors were eliminated or were of little significance. Furthermore, measurement from the midline of the AB, as well as all other measurements undertaken by S.R.M. and A.G. were confirmed by A.U.A. 585 586 Antia, Maxwell, Gough, and Ayeni The midline was established by joining a central point in the suprasternal fossa to the xiphisternal angle, and the distance of the AB and of the nipple was measured from this midline. The extreme medial and lateral ends of the left clavicle were identified and the corresponding points on the skin marked with ink. The length of the clavicle represented by those points marked on the skin was similarly measured. Half of the clavicular length was taken as corresponding to the MCL. During measurements in both the erect and supine positions, the upper arms were lightly pressed against the chest wall so as not to stretch the skin. The chest circumference in full inspiration was measured at the level of the nipples. All measurements were recorded on the centimetre scale to the nearest millimetre. Table 2 Mean apex beat distances from the midline in supine and erect positions for both sexes and according to age Age Supine Erect Student's (years) t-value P n x SD n x SD N 20 2.8 0.4 1- - - - 11 3.8 0-4 - 2- - - - 17 4.1 0-7 - - 3- - - - 12 4.7 0.3 - - 4- 14 4.6 0.5 14 4.6 0.4 0.00 >0-9 5- 37 4.9 0.7 37 5.0 0.8 0.57 >0-5 6- 48 5.0 0-8 48 5.1 0.5 0.73 >0-4 7- 48 5.0 0.7 48 5.2 0.7 1.40 >0. 1 8- 52 5.3 0.8 52 5.4 0.6 0.72 >0-4 9- 48 5.3 0-7 48 5-5 0.5 1.61 >0. 1 10- 46 5-3 0-7 46 5-7 0-6 2-94 <0-01* i = mean; SD = standard deviation; n = number of subjects; N = neonate. 60 Results Out of 1000 children examined clinically, 353 (167 boys and 186 girls) were selected for the study; their ages ranged from birth to 10 years. 337 of the subjects were of Negro descent, 10 were Chinese, and 6 Indian. Table 1 gives the man distances, in erect position, of the AB, MCL, and NPL from the midline. The mean AB distances ranged between 3 * 8 and 5 *7 cm for both sexes and increased with increasing age. In the age group 1 to 3 years, the mean distance of the MCL was significantly less (P<0 05) than that of the AB. By contrast, the mean distance of the MCL at ages 4, 9, and 10, was greater (P<0 05) than that of the AB. The mean distance of the NPL at all ages was consistently greater than that of the AB and MCL, the difference being highly significant (P<0-001). Fig. 1 shows the mean (±2SE) apical distance in the erect position for children aged between 4 and 10 years. The progressive increase in the mean values with increasing age is evident. Table 2 shows the mean apical distances in the erect and supine positions. It will be observed that E 5.5 v Vi ._ a § 45- 4L0 45 6 78 10 Age (years) Fig. 1 Mean 2SE of the apical distance from the midline in erect position according to age. Note the progressive increase in the mean values with increasing age. Table 1 Mean apex beat (AB), midclavicular line (MCL), and nipple line (NPL) distances for both sexes from the midline in erect position according to age Age (years) No. of children Mean distance (cm) ± SD Student's t-values AB MCL NPL AB v. MCL AB v. NPL MCL v. NPL 1- 11 3-8+ 04 3-4 0-3 5-2 + 0-4 2-65* 8.21** 11.94** 2- 17 4.1 i 0.7 3-7 + 0-6 5-6 ± 0.5 1.79 7-19** 10-03** 3- 12 4-7 + 0.3 4-2 + 0.3 5-6 ± 0.5 4.08** 5.35** 8-32** 4- 14 4.6 i 0-4 4.9 i 0.3 6.6 + 0.6 2-24** 10-38** 9.48** 5- 37 5-0 + 0-8 5-1 0.3 6-4 + 0-4 0.71 9.52** 15-82** 6- 48 5-1 ± 0.5 5.2 + 0-4 6.6 ± 0.5 1.08 14.70** 15-lS** 7- 48 5-2 +07 5-3 +0.7 6-6 + -5 0.86 11-28** 14-07** 8- 52 54 +06 54 +04 6-8 +0-6 0.00 11.90** 14.00** 9- 48 5.5 + 0-5 58 + 0-4 7.1 + 0.6 3-25* 14-19** 12-49** 10- 46 5-7 + 0-6 6-0 + 0-4 7-3 + 0-6 2-82* 12-79** 12-23** *Significant difference (P<0.05); **highly significant difference (P<0-001).