posture.
2.The doctor can sit or stand to the right of the patient at the time of percussion.
3.Respiration of the patient should be superficial.
4.The finger-pleximeter (3-rd finger of the left arm) must be densely applied to intercostals spaces to avoid lateral distribution of vibrations along the ribs.
5.Percussion is conducted from a clear sound to dulled or dull depending on the purpose of percussion (that is from lungs to heart).
6.The revealed border of the heart dullness is marked on outside edge of the finger-pleximeter inverted to a louder percussion sound.
7.The strength of percussion stroke depends on the purpose of percussion: at delimitation of relative dullness of heart the medium (quiet, or light) percussion is used, at delimitation of absolute dullness of heart - the quietest percussion.
8.The sequence of percussion:
-Delimitation of relative dullness of heart,
-Definition of a configuration of heart
-Definition of transverse length of relative cardiac dullness,
-Definition of size of heart vascular bundle,
-Delimitation of absolute dullness of heart.
Delimitation of relative dullness of heart
It is distinguished right, left and upper borders of relative dullness of the heart. Determining the borders of relative cardiac dullness, interspaces should be percussed in order to avoid lateral distribution of vibrations along the ribs. The percussion stroke should be of medium strength. The pleximeter-finger should be tightly pressed against the chest so that the percussion vibration might penetrate deeper regions.
In the beginning the right border of relative dullness of the heart is determined. Since the border of cardiac dullness depends on the position of the diaphragm, the lower border of the right lung is first determined in the midclavicular line; its normal position is at the level of the 6-th rib. The position of the lower border of the lung indicates the level of the diaphragm. The various height of position of diaphragm can be reflected in the dimensions of heart and by that on a position of heart in thorax. For this purpose the fingerpleximeter is applied at the level of 2-d intercostals space on midclavicular line, and percussion is performed strictly on intercostals spaces downwards by quiet percussion before change of a clear pulmonary sound on a dull sound. The mark is made on the edge of the fingerpleximeter inverted to a side of a clear pulmonary sound.
Further the right border of relative dullness of the heart can be defined immediately. The pleximeter-finger is moved on two interspace
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above the lower border of the right lung and placed parallelly to the right border of the heart being determined (normally, in the 4-th costal interspace). Percussion is continued by moving the pleximeter-finger gradually along the interspace toward the heart until the percussion sound dulls. The right border of the heart is marked by the external edge of the finger directed toward a clear resonant sound. Its normal position is 1 cm laterally of the right edge of the sternum (Table 4). In case of a change of height of standing of a diaphragm the rules of percussion for definition of the right border of relative dullness are not variated.
In order to definition of the right contour of the heart the finger - pleximeter is located in the 3-d and 2-d intercostals spaces at the level of midclavicular line parallel to a sternum (parallel to a finding border of heart in this intercostals space). Percussion with medium strength is continued by moving the pleximeter-finger gradually along the interspace toward the heart until the percussion sound dulls. Further the points received at a percussion in the 4-th, 3-d, 2-d intercostals space are connected among themselves to representation of a right contour of heart. The right contour of heart is formed at the 2-d to 3-d intercostals spaces by superior vena cava and ascending aortic arch, and at the 4-th intercostals space by right auricle.
Table 4
Normal position of relative heart dullness
Border/ Countour |
Position |
Anatomical structure |
|
|
|
Right - 4-th |
1 cm laterally of the right |
right atrium |
interspace |
edge of the sternum |
|
Right – 2-d and 3-d |
0.5 - 1cm laterally of the |
superior vena cava |
interspaces |
right edge of the sternum |
and an ascending |
|
|
aortic arch |
Left – 5-th interspace |
1-1.5 cm medially of the left |
left ventricle |
|
midclavicular line |
|
Left – 4-th interspace |
more medially than in 5-th |
left ventricle |
|
interspace |
|
Left – 3-th interspace |
on the middle between |
left auricle |
|
midclavicular and |
|
|
parasternal lines |
|
Left – 2-th interspace |
0.5 - 1cm laterally of the |
left part of an aorta |
|
left edge of the sternum |
arch and a |
|
|
pulmonary trunk |
Superior |
on the upper edge of 3-d rib |
cone of a pulmonary |
|
at the left parasternal line |
artery and left auricle |
The left border of the relative cardiac dullness is determined in the interspace, where the apex beat is present Therefore the apex beat is
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first determined by palpation, and the pleximeter-finger is then placed laterally of this point, parallel to the sought border, and the interspace is percussed toward the sternum. If the apex beat cannot be determined, the heart should be percussed in the 5-th interspace from the anterior axillary line toward the sternum. The normal left border of relative cardiac dullness is located 1-2 cm medially of left midclavicular line; it coincides with the apex beat.
Definition of the left contour of the heart begins with definition of localization of the apex beat. Further the left border of relative dullness of the heart is determined (in norm it settles down in the 5-th intercostal space on 1 sm medially from midclavicular line). Next the pleximeter-finger is raised on one intercostals space above, the pleximeter-finger position in the 4-th intercostals space is parallel to sternum at the level of anterior axillary line, and percussion is performed before change of a clear pulmonary sound on a dulled sound. The point is marked from the side of a clear note. Percussion in the 3-d intercostal space is performed by the same rules. Later the left border of heart vascular bundle in the 2-d intercostals is defined by percussion from midclavicular line to sternum before change of a clear pulmonary note on a dulled sound. The points received by means of percussion in the 5-th, 4-th, 3-d, 2-d intercostals spaces are connected and represents about the left contour of heart.
The left contour of the heart is formed in the 2-d intercostals space by the left part of the aorta arch and the pulmonary trunk, at the 3-d intercostals space - the left auricle, and lower - left ventricle.
The superior border of relative cardiac dullness is determined on a left parasternal line (1-2 cm to the left of left sternal line). To that end the pleximeter-finger is placed at the 1 -t intercostals space perpendicularly to the sternum, and then moved downward until dullness appears. The normal superior border of the relative cardiac dullness is located in the 3-d intercostals space.
For more accurate determination of the superior border the immediate percussion (Obraztcov method) is performed on two overlying ribs above a dulled sound (first – the 2-d control rib, then – the 3-d test rib). If the percussion by ribs yields an identical note, the border is placed on the inferior edge of the lower (the 3-d) rib. If the dull percussion sound is found above the lower rib, the superior border is defined on the upper edge of this rib.
The normal superior border of relative cardiac dullness is located at the level of the upper edge of the 3-d rib and is formed by a cone of a pulmonary artery and the left auricle.
The enlargement of relative dullness of the heart is observed under the following conditions:
- elevated position of diaphragm (in hypersthenic constitution,
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meteorism ascites, pregnancy);
-in hypertrophy and dilatation of the right auricle and the right ventricle (in stenosis and incompetence of tricuspid valve, stenosis of ostium of the pulmonary artery, sclerosis of the pulmonary artery, development of the pulmonary heart, mitral stenosis) the borders of heart are displaced to the right;
-as a result of the hypertrophy and dilatation of the left ventricle (in arterial hypertension, stenosis of ostium of aorta, incompetence of the aortal valves, aneurysm of the left ventricle) the borders of heart are displaced to the left;
-as a result of the hypertrophy of the left auricle (mitral stenosis and incompetence of the mitral valve) the borders of heart are displaced upwards;
-as a result of combined heart valves diseases the enlarging of the dimensions of heart is observed in all directions.
The restriction of the relative dullness of heart is observed:
-as a result of phrenoptosis (descent position of a diaphragm in asthenic constitution, at the general enteroptosis);
-as a result of pulmonary pathology (pulmonary emphysema).
Determination of a configuration of heart
The shape of the heart can be determined by percussion of the borders of the vascular bundle in the 2-th intercostal space on the right and left, and of relative cardiac dullness in the 4-th or 3-rd interspace on the right, and in the 5-th, 4-th, or 3-rd interspaces on the left. The pleximeter-finger is moved parallel to the borders of expected dullness and the elicited points of dullness are marked on the patient's skin. The points are connected later by a line to mark the contours of the relative cardiac dullness. Normally, an obtuse angle is formed by the lines of the left heart contour between the vascular bundle and the left ventricle. The narrowing of contours of relative cardiac dullness is normally placed at the 3-d intercostal space and named «waist of heart». The heart is of normal configuration in such cases. In pathological conditions, when the chambers of the heart are dilated, mitral and aortal configurations are distinguished.
The angle formed by the vascular bundle and the left contour of heart becomes more significant when the left ventricle is enlarged. Since it is more pronounced in aortic incompetence and aortic stenosis, this configuration of heart is known as "aortic configuration ". The left atrium is enlarged and the pressure in the pulmonary artery increases in mitral incompetence and mitral stenosis. In this connection «waist of heart» becomes smooth. This configuration of the heart is known as "mitral configuration".
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Percussion shows considerable enlargement of the cardiac dullness in all directions in pericarditis with effusion. Absolute and relative dullness are almost indistinguishable. The area of dullness resembles a trapezium or a triangle. This configuration of the heart is known as "trapezoidal configuration".
"Spherical configuration", or "cor bovinum", is characterized by the enlargement of heart in all directions as a result of combined heart valves diseases, congenital heart disease, dilated cardiomyopathy, diffuse cardiosclerosis.
Determination of transverse length of relative cardiac dullness
Once the area of relative cardiac dullness of the heart has been established, its transverse length is measured by a measuring tape, from the extreme points of the relative dullness to the anterior median line. The normal distance from the right border of relative cardiac dullness (usually in the 4-th intercostals space) to the anterior median line is 3 or 4 cm, while the distance from the left border of relative cardiac dullness (usually in the 5-th intercostals space) to the same line is 8 or 9 cm. The sum of these lengths is the transverse length of relative cardiac dullness (normally 11-13 cm).
Determination of size (width) of a vascular bundle
The vascular bundle of heart is formed: on the right - by cava vein and an ascending part of an aortic arch, on the left -by a pulmonary artery and a part of an aortic arch. The vascular bundle of heart can be determined by percussion of the borders of relative heart dullness in the 2-nd intercostal space on the right and left. The borders of the vascular bundle are determined by quiet (light) percussion in the second intercostal space, to the right and left from the midclavicular line, toward the sternum. When the percussion sound dulls, a mark should be made by the outer edge of the finger. The right and left borders of vascular dullness are normally found along the edges of the sternum; the transverse length of dullness is 5—6 cm.
Delimitation of absolute (superficial) cardiac dullness
The part of anterior wall of the right ventricle heart is not covered normally by the lungs. Percussion of the anterior wall of heart not covered by the lungs area produces the dull sound and reveals the absolute cardiac dullness of the heart. To determine absolute dullness of the heart, the quietest (lightest) percussion strokes are needed. The right border of absolute cardiac dullness is first elicited. The pleximeter-finger is placed on the right border of relative (deep) cardiac dullness, parallel to the sternum, and then moved medially, to the left, to dullness (change a dulled note on dull). The border is marked by the outer edge of the finger directed toward resonance. In normal subjects this border passes along the left edge of the sternum (Table 5).
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