542 PHYSICAL EXAMINATION OF THE CIRCULATORY ORGANS. 



CHAPTER XXV. 



PHYSICAL EXAMINATION OF THE CIRCULATORY ORGANS, THE 

 HEART CHIEFLY. 



In endeavouring, by observation and study of tbe condition 

 and action of tlie heart, to obtain some knowledge indicative 

 of general or special diseased states, we may, in addition to 

 the assistance derived from observation of the sounds properly 

 so-called both in health and disease, be further helped if we 

 give attention to the information afforded by simple ' inspec- 

 tion ' and ' palpation.' By these we may judge of the position 

 of the heart, the force or impulse of the pulsations, the changes 

 of these in the great vessels of the neck, the frequency of 

 the heart's action, and the regularity or constancy of its 

 movements. 



To succeed to any extent, and to be even moderately accurate 

 in our observations of cardiac action and sounds in the horse, 

 great care is needful to ensure that the animal to be examined 

 is not or has not lately been excited or disturbed, either by 

 exercise or in any way to cause excitement or increase of 

 cardiac function. 



I. Cardiac Impulse. 



To determine the impulse of the heart, the hand, or stetho- 

 scope or ear, must be placed directly over the cardiac space of 

 the thorax on the left side, and by either or both of these 

 modes the position, the force or impulse, character and rhythm 

 of the heart's action appreciated. Allowance must be made 

 for form of chest, extent to Avhich the walls are clothed with 

 soft tissue, and also for the breed of the animal. 



In considering the cardiac impulse the chief points for 

 examination are — (1) The 2^osition and area of occiqmtion ; 

 (2) Force and character ; (3) Rhythm. 



1. Position and Definition. — The impulse may suffer altera- 

 tion in position from causes directly connected with the heart- 

 structures, or from changes acting from without the proper 

 cardiac area. The chief of these are — {a) Displacement of the 

 organ forwards and upwards, from abdominal distension 

 operating through pressure upon the diaphragm ; {h) Displace- 



