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Abnormal heart sounds (Ss and S•) with acute Myocardial infarct
myocardial infarction: Prognostic significance of changes detected by phonocardiography and auscultation LAWRENCE U. HASPEL, D.O. Chicago, Ill.
Ventricular and atrial gallops should be looked for in any patient suspected of having myocardial infarction. They help to confirm the diagnosis, along with the history, electrocardiograms, and serum enzyme values. Ventricular and atrial gallops are pathologic third and fourth heart sounds which occur in diastole. Ventricular gallop is an accentuation of the third heart sound. It is a common finding that may be present in a great variety of heart diseases. Although it does not always appear with myocardial infarction, it may be one of the first detectable signs of a failing myocardium. When this gallop persists, it indicates a poor prognosis. It is a sign of cardiac decompensation. Atrial gallop is an accentuation of the fourth heart sound in late diastole. It represents a decrease in left ventricular compliance. This sign occurs in nearly all instances of acute myocardial infarction. Some illustrative phonocardiograms of patients suffering from acute myocardial infarction demonstrate the presence of pathologic ventricular and atrial gallops.
Although in most cases the diagnosis of acute myocardial infarction can be based on history, the electrocardiogram, and serum enzyme levels, the finding of abnormal heart sounds by auscultation and phonocardiography helps to confirm the diagnosis.
The purpose of this paper is to review the significance of these abnormal sounds (S 3 and S4 ) in terms of frequency of appearance, genesis, characteristics, and effect on prog- nosis.
The abnormal sounds to be discussed are referred to as gallops (ventricular and atrial) . Both the ventricular and the atrial gallop oc- cur in diastole and represent pathologic third and fourth heart sounds. The term gallop rhythms refers to the auscultatory finding of an audible three-sound sequence to each heart beat, instead of the normal two-sound (lub- dub) pattern of the first and second heart sounds.
The abnormal extra sound never occurs in systole, but is always a diastolic event. It is brief and of low frequency. In general, gallop rhythms produced by the left side of the heart are heard best at the cardiac apex; those pro- duced in the right side of the heart, along the lower • left sternal border. The three-sound sequence to each heart beat at rates above 100 per minute sounds on auscultation like a horse's gallop.
Ventricular gallop The ventricular gallop is an accentuation of the third heart sound and resembles the sound of the word "Kentucky." Harvey' made this comment:
The ventricular diastolic gallop often has clinical con- notations different from those of the atrial gallop. It is frequently one of the first signs that one can de- tect, indicating serious heart disease and/or cardiac decompensation. This gallop appears in the early part of diastole, later in timing than the opening snap but
Journal AOA/vol. 71, May 1972 771/49
Disease
Abnormal heart sounds with acute myocardial infarction
at the same time as the normal physiologic third heart sound found in youth. If searched for, the ventricular diastolic gallop is a common finding and can appear in a great variety of diseased states of the heart, includ- ing coronary hypertensive, primary myocardial (car- diomyopathies), rheumatic, congenital, and syphilitic disorders. The common denominator when a ventric- ular diastolic gallop is present, regardless of the cause of the heart disease, is cardiac decompensation.
The ventricular gallop is the pathologic counterpart of the physiologic third heart sound, having the same phonocardiographic characteristics. The normal third sound is pro- duced in the open left ventricle and atrium toward the end of the period of rapid empty- ing of the atrial contents into the ventricle.
Luisada2 stated:
The third sound occurs when intraventricular volume and "accommodation" of the ventricular wall reach a balance, and intramural tension begins to rise once more. A possible energy source is embodied in the blood volume present in the ventricles at the time of transition from active relaxation to passive distention. Once "active relaxation" has ceased, each ventricle must of necessity adjust to accommodate the volume of blood it contains. An increased intraventricular volume would increase the distending force and ac- centuate the third sound. This concept explains the accentuated third sound which is observed both in con- ditions with increased residual volume (heart failure) and in those with volume overload and high output.
The sound is usually inaudible in normal adults, but may become exaggerated and audible in patients with an abnormal state in which the volume of early filling is increased or there is incomplete emptying during the prior systole. On the phonocardiogram the third heart sound occurs between 0.12 and 0.18 sec- ond after the aortic component and corre- sponds to the end of the rapid filling wave of the apexcardiogram. Master and Friedman3 reported in 1942 that a third sound was dem- onstrated in 47 percent of patients with acute myocardial infarction. More recently Hill and associates4 reported a 65 percent incidence of ventricular gallop with acute infarction.
Harvey' commented:
The deliberate effort to search for gallop rhythm will be rewarded, because the ventricular diastolic gallop may be the first and only clinical sign of a failing myocardium. It may serve as the first indication for digitalization and restriction Of sodium in the diet.
It is believed that a ventricular gallop that persists despite treatment for congestive heart
Fig. 1. Development of S, and S4 gallops. (Adapted from Shale.)
failure has grave prognostic significance after myocardial infarctions. The atrial gallop, on the other hand, may persist forever.
Atrial gallop The atrial gallop is an accentuation of the fourth heart sound in late diastole and re- sembles the sound of the word "Tennessee." Harvey'. stated:
This gallop sound is related to atrial contraction and may occur with or without any clinical evidence of cardiac decompensation.
The normal fourth heart sound is produced by vibration of the blood column in the open atrium and ventricle during atrial contraction. Shah and associates5 in 1968 proposed an out- line (Fig. 1) of the mechanisms involved in the production of atrial and ventricular gallop.
The atrial gallop usually occurs close to the first heart sound and follows the "a" wave of the apexcardiogram. Harvey' said:
If one searches carefully for an atrial sound or gallop, it is most commonly heard in those having coronary artery disease, and at times this may be one of the first clues from the physical examination as to the presence of underlying heart disease. . . . The atrial gallop sound associated with myocardial infarc- tion may be prominent or faint. The sound is often louder during the episode of acute coronary pain, or during the initial phases of myocardial infarction. Subsequently, usually with improvement, the gallop is fainter, but if carefully searched for, can generally be heard.
Hill and associates4 reported that 98 percent of patients with acute myocardial infarction had atrial gallop. Since almost all patients
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Fig. 2. Simultaneous recording of EKG, low frequency phonoca'rdiogram, and apexcardiogram with S3 and S gallops in patient with acute inferior infarct.
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Fig. 3. Simultaneous recording of EKG and low frequency phonocardiogram with Ss and S4 gallops in patient with acute inferior infarct.
Journal AOA/vol. 71, May 1972 773/51
4
EKG
Fig. 4. Simultaneous recording of EKG, low frequency phonocardiogram, and apexcardiogram with S, gallop in a patient with acute anterior septal infarct.
with acute myocardial infarction had an atrial diastolic gallop, they concluded that when this sound is absent in a patient with chest pain and sinus rhythm the probability of a diag- nosis of acute myocardial infarction is les- sened.
Figures 2-4 are phonocardiograms of sev- eral patients who suffered acute myocardial infarction. They illustrate the presence of pathologic ventricular and atrial gallops. The phonocardiograms were taken with a Sanborn recorder utilizing a Krohn-hite band-pass fil- tration system.
Figure 2 shows the phonocardiogram and apexcardiogram of a 58-year-old Negro man
who was hospitalized with acute chest pain of 8 hours' duration. The electrocardiogram and serum enzyme levels confirmed the diagnosis of infarction of the inferior wall. The phono- cardiogram shows both ventricular and atrial gallop. Digitalization was begun, and the pa- tient's ventricular and atrial gallops persisted. Eventually, ventricular fibrillation developed, and the patient died.
Figure 3 is the phonocardiogram of a 58- year-old Caucasian man who was hospitalized with chest pain and shortness of breath. Serum enzyme elevation and the electrocardiogram confirmed a diagnosis of inferior wall infarc- tion. The phonocardiogram of this patient
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showed marked improvement in his shortness of breath. The ventricular gallop disappeared several days after digitalization. However, the atrial gallop persisted and was present at the time of discharge from the hospital.
Figure 4 is the phonocardiogram of a 60- year-old Caucasian man who was hospitalized with severe pain in the left shoulder and arm and accompanying nausea and emesis 24 hours prior to admission. The electrocardiogram and serum enzyme elevations confirmed the diag- nosis of anterior septal infarction. The phono- cardiogram of this patient revealed a prom- inent atrial gallop, which persisted and was present at the time of discharge 4 weeks after- ward.
Summary The genesis and importance of gallop rhythm in the diagnosis, treatment, and prognosis of patients suffering acute myocardial infarction have been considered.
Ventricular gallop appears less frequently than atrial gallop with myocardial infarction but is an early indication of cardiac decompen- sation. If it persists, the prognosis is poor. Atrial gallop occurs in almost all cases of acute myocardial infarction and may persist for a lifetime. It represents a decrease in compliance of the left ventricle.
Both ventricular and atrial gallop should be sought vigorously in any patient suspected of myocardial infarction, since they both help to
confirm the diagnosis and provide early signs of cardiac decompensation.
1. Harvey, W.P.: Gallop sounds, clicks, snaps, and other sounds. In the heart, arteries and veins. Ed. 2. Edited by J.W. Hurst and R.B. Logue. McGraw-Hill Book Co., New York, 1970 2. Luisada, A.A.: Phonocardiography. A dynamic interpretation of the normal and abnormal precordial vibrations. In Clinical cardiopulmonary physiology. Ed. 3. Edited by B.L. Gordon, R.A. Carleton, and L.P. Faber. Grune and Stratton, New York, 1969 3. Master, A.M., and Friedman, R.A.: Phonocardiographic study of the heart sounds in acute coronary occlusion. Am Heart J 24:196-208, Aug 42 4. Hill, J.C., et al.: The diagnostic value of the atrial gallop in acute myocardial infarction. Am Heart J 78:194-201, Aug 69 5. Shah, P.M., et al.: Determinants of atrial (S 4 ) and ventricular (S3) gallop sounds in primary myocardial disease. N Engl J Med 278:753-8, 4 Apr 68
Dr. Haspel was the recipient of a 1970-71 National Osteopathic Foundation grant through the cooperation of the Smith Kline and French Foundation.
This paper was written while Dr. Haspel was serving a fellowship in cardiology at Mt. Sinai Medical Center, Chicago Medical School. He is now on the staff of Chicago Osteopathic Hos- pital.
Dr. Haspel, 1700 E. 56th St., Chicago 60637.
Journal AOA/vol. 71. May 1972 775/53