DISEASES OP HEART, BLOOD VESSELS, AND LYMPHATICS. 259 



blood passes, or preventing a proper coaptation of the valves, which 

 may produce most serious valvular disease. 



Symptoms. — These are frequently uncertain; they may, however, 

 be suspected when the action of the heart suddenly becomes embar- 

 rassed with irregular and confused pulsations, great difficulty of 

 breathing, and the usual signs dependent upon the imperfect ar- 

 terialization of the blood. 



Treaiment. — Stimulants, whisky, or carbonate of ammonia may 

 be of service. 



PALPITATION OF THE HEART. 



This is a tumultuous and usually irregular beating of the heart. 

 It may be due to a variety of causes, both functional and organic. 

 It may occur as a result of indigestion, fright, increased nervous- 

 ness, sudden excitement, excessive speeding, etc. (See "Thumps," 

 p. 225.) 



Symptoms. — The heart may act with such violence that each beat 

 may jar the whole body of the animal; very commonly it may be 

 heard at a short distance away from the animal. It can usually be 

 traced very readily to the exciting cause, which we may be able to 

 avoid or overcome in the future and thereby obviate subsequent 

 attacks. Eest, a mild stimulant, or a dose or two of tincture of digi- 

 talis or opium will generally give prompt relief. When it, is due to 

 organic impairment of the heart it must be regarded as a symptom, 

 not as a matter of primary specific treatment. 



SYNCOPE, OR FAINTING. 



Actual fainting rarely occurs among horses. It may, however, be 

 induced by a rapid and great loss of blood, pain of great intensity, a 

 mechanical interference with the circulation of the brain, etc. 



Sym,ptomjS. — Syncope is characterized by a decrease or temporary 

 suspension of the action of the heart and respiration, with partial or 

 total loss of consciousness. It generally occurs suddenly, though 

 there may be premonitory symptoms, as giddiness, or vertigo, dilated 

 pupil, staggering, blanching of the visible mucous membranes, a rap- 

 idly sinking pulse, and dropping to the ground. The pulse is feeble 

 or ceases to beat; the surface of the body turns cold; breathing is 

 scarcely to be perceived, and the animal may be entirely unconscious. 

 This state is uncertain in duration — ^generally it lasts only a few 

 minutes; the circulation becomes restored, breathing becomes more 

 distinct, and consciousness and muscular strength return. In cases 

 attended with much hemorrhage or organic disease of the heart, the 

 fainting fit may be fatal; otherwise it will prove but a transient 

 occurrence. In paralysis of the heart the symptoms may be exactly 

 similar to syncope. Syncope may be distinguished from apoplexy by 



