HEART.
Wounds of the Heart and Pericar dium. — Practically all wounds of the heart are bullet and stab wounds. Lac erations by broken bones are included under rupture of the heart.
Fischer's statistics prove that the most important parts of the heart function ally, the ventricles, are much more liable to wounds than the auricles: 257 wounds of the ventricles, against only 31 of the auricles, which might be expected from the smaller size and less exposed posi tion of the latter. Editorial (Jour. Amer. Med. Assoc., June 13, '96).
–As a rule, a wound of the heart is immediately fatal: the wounded man drops dead incontinently. Yet in a few cases the fatal issue is postponed or averted, and foreign bodies have been found imbedded in the wall of the heart, though they produced no symptoms during life.
The few who escape immediate death are usually found in a condition of col lapse: the product of shock and hmmor rhage. But some persons, among whom the late Empress of Austria was a nota ble example, escape this shock and con tinue to walk, fight, or go about their various avocations for a few moments or even for a few days or weeks, at the end of which time the heart suddenly stops.
If the patient survives the immediate shock, examination of the chest reveals the external wound bleeding copiously if in direct communication with the wound in the heart. The area of car diac dullness is enlarged by an effusion of blood within the pericardium (Immo pericardium), or perhaps obliterated if the pericardium is filled with' air (pneu mopericardium) from an adjacent wound in the lung and pleura. in which case there is pneumohremothorax. Ausculta tion reveals a weak, irregular heart action and numerous atypical murmurs. A special sound heard with pneumo pericardium or pneumohamothorax in the vicinity of the heart is the "mill wheel sound." This is a succussion caused by, and synchronous with, the heart's action.
The immediate danger of death is now from hemorrhage, associated in juries, and from compression, actual smothering, of the heart by the blood in the pericardial sac. Escaping these dan
gers, fatal embolism, secondary hremor rhae, and infection are still possible; and. if the patient finally does survive, the heart may he permanently debili tated by pericardial adhesions, cicatrices about the valves, perforation of the in terventricular septum, etc.
Fischer, who chronicles 334 wounds of the heart, exclusive of rupture, and 42 of the pericardium alone, records •7 recoveries (14 per cent.) in the former class and 1S (42 per cent.) in the latter. While these figures are misleading as to the proportion of recoveries, they show that recovery is possible.
— The history and evi dence of a wound in the pnecordial re gion, together with marked irregularity of the heart's action and increase in the area of cardiac dullness, or rarely ob literation of it with "mill-wheel" succus sion, those, together with severe shock, usually constitute the diagnostic features of a wound of the heart.
Here, even more than in wounds of the lung, the use of the probe is bad surgery. It can reveal nothing that may not be discovered in some other way, and it may kill the patient.
—When instantaneous death follows a wound of the heart it is probably due to the shock inflicted on the automatic heart-muscle and its con tained ganglia, in response to which it stops instantly.
The aseptic healing of a wound in the heart requires a week. The blood effused in the pericardium may become infected or be absorbed, leaving an ad hesive pericarditis.
The bullet wounds of the modern rifle have a special pathology. If they so much as graze the heart they impart to its fluid contents such a rapid vibration as to burst the organ asunder.
— Up to within a few years the treatment of lesions of the heart has been similar to that of injuries of the lung, supporting and expectant; but the accumulated evidence in favor of paracentesis pericardit has at last em boldened the surgeon to attack the heart itself.