Gallop Sounds Research Articles

Experimentally Produced Gallop Rhythm. A Preliminary Report

Summary.In order to illustrate the question of the appearance and significance of the gallop rhythm and the third sound gallop, in particular, experimental tests were initiated. Fleisher and Loeb's method was employed for producing myocarditis in rabbits. In about 1/3 of the 30 animals surviving an injection, the gallop rhythm was registrable by means of the phonocardiogram. A closer analysis showed, that this was a case of the third sound gallop (i.e. protodiastolic gallop or rapid filling gallop). In all these instances considerable changes were ascertained in the electrocardiogram and often a marked dilatation of the heart. The patho‐anatomical examination, as a rule, revealed a certain degree of hypertrophy and more or less extensive fibrosis in the myocardium.

THE ORIGIN OF HEART SOUNDS AND THEIR VARIATIONS IN MYOCARDIAL DISEASE

During every generation since Rouanet advanced the theory that all heart sounds are purely valvular, a few outstanding cardiac specialists have supported that view.1Many physiologists and most writers of medical textbooks have accepted the compromise that the first sound and the gallop sounds are partly muscular in origin, and not a few men distinguish the muscular from the valvular element in describing their auscultatory observations. An attempt to distinguish the muscular and valvular elements in experiments on dogs ended in demonstrating that the first sound was purely valvular,2since vigorous contractions occurred with no audible vibration when venous filling was cut off or the auriculoventricular groove compressed with a ligature which closed off the arterial outlets as well. A study of our records of human heart sounds and those reported by Lewis,3Wolferth and Margolies4and Houssay5has strengthened the conviction that the three

Gallop rhythm and the physiological third heart sound: I. Characteristics of the sounds, classification, comparative incidence of the various types and differential diagnosis

1. 1. The only available criterion for distinguishing between physiological third heart sounds and gallop rhythm is the status of cardiac function. Both types of sound are accentuated by the same procedures. They have similar time relations, quality and intensity. Their positions of maximum audibility are identical except that right-sided physiological third heart sounds are unknown. 2. 2. Gallop and physiological third heart sounds invariably fall in either the protodiastolic or the auriculosystolic time zone. 3. 3. When these two time zones become superimposed, either as a result of tachycardia, minor grade heart block, sinus arrhythmia or auricular extrasystoles, gallop sounds may either appear for the first time, or, if already present, become markedly accentuated. This effect is so pronounced as to constitute a summation phenomenon. 4. 4. The hypothesis of summation is in accord with all known facts regarding gallop rhythm. Moreover, it offers a reasonable explanation for some of the variations in gallop sounds hitherto unaccounted for. 5. 5. A classification of physiological third heart sounds and gallop rhythm, based on Potain's classification of gallop rhythm, but altered to correspond with objective phenomena, is proposed. The erroneous concept of mesodiastolic gallop is discarded, and summation gallop is recognized. The classification abolishes the practical difficulties, heretofore encountered so frequently, in placing cases into proper categories. 6. 6. There appears to be no great disparity in the incidence of presystolic or protodiastolic gallop. Summation gallop is little if any less frequent. In can be produced in cases with either of the other types of gallop, or in cases with a predisposition to gallop, by the simple expedient of accelerating the cardiac rate enough to bring about superimposition of protodiastolic and presystolic events. 7. 7. Potain's conception of right-sided gallop rhythm, disputed by certain observers, has been confirmed by our investigations. It tends to occur in cases exhibiting predominantly right-sided heart failure. 8. 8. In the differential diagnosis of gallop rhythm and the physiological third heart sound, errors have been encountered involving one or another of the following: (1) the opening snap of mitral stenosis; (2) mid-diastolic murmur; (3) presystolic murmur; (4) reduplicated first heart sound; (5) reduplicated second heart sound. Other possible sources of error are (a) pericardial friction sound; (b) mid-systolic click; and (c) the so-called systolic gallop rhythm. In the great majority of cases differentiation is possible by clinical methods alone. In occasional cases, however, accurate timing requiring graphic methods is necessary.

Observations on Heart Sounds with Particular Reference to Gallop Rhythm and Sounds of Auricular Origin.

Observations on Heart Sounds with Particular Reference to Gallop Rhythm and Sounds of Auricular Origin.

Observations on Heart Sounds with Particular Reference to Gallop Rhythm and Sounds of Auricular Origin

The study of a large number of phonocardiograms from a series of patients with heart disease and from normal subjects suggests the tentative conclusions enumerated below. Two Einthoven galvanometers coupled in tandem were used to record the electrocardiogram and the heart sounds simultaneously and the electric stethoscope manufactured by the Western Electric Company was used to convert the sounds into electrical variations.From the graphic standpoint gallop rhythm may be defined as a condition in which 3 sounds occur during each cardiac cycle; 3 or perhaps 4 varieties may be distinguished.(a) Protodiastolic gallop rhythm in which the extra sound follows the second heart sound by a constant interval and occupies the same position in the cardiac cycle as the normal third heart sound.(b) Presystolic gallop rhythm in which the extra sound precedes the first heart sound by a constant interval, and is almost certainly of auricular origin. The onset of the extra sound falls within the P-R interval of the electro...

The opening snap ( Claquement d'ouverture de la mitrale) in mitral stenosis, its characteristics, mechanism of production and diagnostic importance

1. 1. The opening snap ( claquement d'ouverture de la mitrale) can be heard and recorded in more than half the cases of mitral stenosis. It has not been observed in the absence of mitral stenosis. It is one of the most important diagnostic signs of this valvular lesion. 2. 2. The chief characteristics of the opening snap are the following: (a) The sound is a sharp snap or click. (b) It has been found to occur from 0.03 to 0.19 second after the beginning of the second sound, the ordinary range being 0.06 to 0.11 second. (c) It is usually loudest in the fourth left interspace, occasionally in the third, slightly above and to the right of the area in which the diastolic murmur is best heard. (d) It precedes the onset of the murmur by a short interval. (e) It is usually best elicited with the patient in the recumbent position. (f) In some cases it can be brought out by exercise and by increase of the cardiac rate. (g) It tends to be louder when the rate is rapid. 3. 3. The interval between the second heart sound and the opening snap is influenced by the cardiac rate, tending to become shorter as the rate increases. Variations in the duration of this interval occur during auricular fibrillation and sinus arrhythmia depending on the length of the preceding heart cycle. 4. 4. The opening snap is easily differentiated from reduplication of the second sound, protodiastolic gallop sounds, the physiological third heart sound and systolic clicking sounds. 5. 5. The time relations of the opening snap, as observed from comparisons of sound tracings with electrocardiograms, apex cardiograms, jugular phlebograms, auricular and ventricular roentgen kymograms, exclude auricular contraction, ventricular rotation or filling, or shock-like waves transmitted from the aortic to the mitral valve, as factors in its production. All the evidence thus far available is in accord with the hypothesis that the sound is produced by the sudden limitation of the opening movement of a stenosed mitral valve which occurs in early diastole as soon as the left ventricle relaxes sufficiently to permit the pressure of the auricular blood column to become effective.