CARDIAC THROMBOSIS.
BY BEVERLEY ROBINSON, M.D.
DEFINITION.—In general, this name is given to every deposit of coagulated blood or fibrin in one or more of the cardiac cavities. By its derivation ([Greek: thrombôsis], coagulation, from [Greek: thrombys], clot) it further implies the manner in which the coagulum is formed and all the morbid alterations connected with it.
SYNONYMS.—Heart-clot. Fr. Thrombose cardiaque; Ger. Blutgerinnungen im herzen; Lat. Thrombosis cordis; It. Trombo; Sp. Trumbo.
The definition offered is not wholly satisfactory, because, although it is accurate as far as it goes, it is not complete. It does not distinguish between concretions of different origin, etiology, mode of formation, and age. No separation is made between fibrinous deposits which increase from the beginning and layer by layer in the cavities of the heart, and those transported there from a distance and forming a nucleus for fresh deposits. To make the definition anything like exhaustive would require many references to the general history of THROMBOSIS AND EMBOLISM; we therefore direct our readers to that article for what relates to the common facts of these morbid processes, retaining for the present only those matters which relate specially to the heart.
Heart-clots may be formed—1, during life, when the patient enjoys, apparently, good health and strength; 2, toward the termination of life, when the general forces are evidently depressed, or at the final stage, when life ebbs low and the agony has appeared; 3, after death. These clots have therefore been divided into cadaveric clots, those of the agony, and ancient clots. To the clots of the agony exception is properly taken, for the reason that agony is a term employed with a somewhat badly-defined signification. At what period does it begin? Is it not frequently of different length? Does it always exist? The answers to these different questions render our objection proper, and show that we had better employ the word terminal for coagula of the second division.
Manifestly, the separate varieties of coagula have not an equal importance. The clots which are post-mortem productions are only interesting for their physical characters, which, fortunately, are well marked, and enable us at once to distinguish them from the two other varieties. The coagula in the first two divisions have an interest both clinical and pathological.
The ancient clots are invariably accompanied with signs and symptoms which should reveal their presence. As much might be affirmed for the terminal clots in the majority of instances and when the patient is not already in extremis. The pathological study of these varieties has great value, and especially in so far as it will the better enable us to distinguish the clots formed some time previous to death—be it of shorter or longer duration—from those which are but the result of the gradual stagnation of the blood-current in a weakened and wellnigh powerless organ. Amongst the clots which are formed in the venous system, some are transported, and pass immediately through the heart, to be arrested finally in some of the larger or smaller arterial trunks, whilst others remain in situ in the heart, and are constantly increased by successive additions or layers of new fibrin or cruor.