The clinical diagnosis of acute severe mitral insufficiency

Reviews

The Clinical Diagnosis of Acute Severe Mitral Insufficiency

JAMES A. RONAN, JR., MD R. BARRETT STEELMAN, MD ANTONIO C. DeLEON, Jr, MD T. JAMES WATERS, MD, FACC JOSEPH K. PERLOFF, MD, FACC W. PROCTOR HARVEY, MD, FACC Washington,

II. C.

The

clinical and hemodynamic data of 8 patients with acute severe mitral insufficiency are presented. The natural history, physical signs, electrocardiogram, X-ray films and findings at cardiac catheterization present a characteristic picture which is distinct from the chronic form of the disease. The murmur is loud, apical and holosystolic with a late systolic decrease. It frequently radiates towards the base, mimicking aortic stenosis, and it is accompanied by an atrial sound and a third heart sound. Physical findings of pulmonary hypertension are present. Left atriaf enlargement and atrial fibrilfation are conspicuous by their absence. The basic pathology lies in the suspensory apparatus of the valve rather than in the leaflets. Four patients had ruptured chordae tendineae. If careful attention is paid to all of the clinical features, an accurate diagnosis can usually be made on clinical grounds alone.

Acute severe mitral insufficiency has long been recognized but has only recently been identified as a distinctive clinical disorder. The hemodynamic and clinical manifestations differ from those of equivalent degrees of chronic severe mitral regurgitation. Despite a lively interest in the acute severe variety of the disease,1-0 a number of its features remain ill-defined. This is especially so regarding the natural history and physicai signs. Accordingly, clinical, hemodynamic and angiographic observations were made in 8 patients with isolated acute severe mitral incompetence. When the history, physical signs, electrocardiograms, and X-ray films were carefully analyzed, a relatively characteristic picture emerged. The purpose of the following report is to clarify this picture upon which a confident clinical diagnosis can generally be based.

Materials and Methods

From the Department of Medicine, Division Georgetown University of Cardiology, School of Medicine, Washington, D. C. This study was supported by grants from the U. S. Public Health Service, the Benjamin May Memorial Fund and the Special Cardiac Fund. Manuscript received January 21. 1970, accepted March 12, 1970. Address for reprints: James A. Ronan, Jr., MD, Division of Cardiology, Georgetown University Hospital, Washington, D. C. 20007.

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Seven patients were male and 1 was female. The ages of the men ranged from 40 to 70 years (average 58) ; the woman was 20 years old (Table I). Each patient was evaluated by at least 3 of us. Phonocardiograms were taken in 7 instances with a Sanborn model 350-1700B heart sound preamplifier and recorded on a photographic recorder. All patients underwent hemodynamic investigations by standard methods of right and left heart catheterization ; 7 of the 8 had left ventricular cineangiocardiograms obtained in the right anterior oblique projection. Left atria1 pressures were measured directly in 4 patients and by means of pulmonary capillary wedge pressure in 4. The cause of the mitra1 incompetence in 4 subjects was rupture of the chordae tendineae, which was surgically corrected at open operation (Dr. Charles A. Hufnagel). Two subjects had coronary artery disease

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TABLE I History and Physical Examination

Case no.

Age and Sex

Diagnosis

History of Murmur (mo)

Configuration of Murmur

Apical Thrill

Basal Thrill

Radiation to Base

Radiation to Axilla

pulse

RV Im-

Loud P-2

Audible Atrial Sound

Third Heart Sound

+

+

+

+

Ruptured known

chordae tendineae, uncause. Anterlor leaflet

45M

24

Holosystolic with late decrease

+

0

0

0

++

Ruptured known

chordae tendineae, uncause. Posterior leaflet

48M

12

Halosystolic with late decrease

+

0

+

0

0

Ruptured chordae tendineae with an enlarged posterior leaflet

64M

13

fiolosystolic with late decrease

+

0

+

0

+

0

0*

+

Ruptured chordae tendineae from endocarditis. Anterior leaflet

20F

2

Holosystolic with late decrease

+

0

+

0

+

+

$

+

Unknown

51M

6

Holosystolic with late decrease

+

0

+

0

+

+

0*

+

Coronary artery disease with “papillary muscle dysfunction”

56M

36

Holosystolic with late decrease

0

0

+

+

0

0

+

+

Unknown

59M

12

Holosystolic with late decrease

+

+

+

+

0

+

+

+

Coronary artery disease with “papillary muscle dysfunction” Totals

70M

5

Ended

0

0

0

0

0

+

+

+

l/8

618

218

418

518

618

818

before

S-2

Average

618

0

=12mo * Present on phonocardiogram. P-2 = pulmonary component

of second

heart

sound;

RV = right ventricular.

demonstrated

by selective coronary cineangiocardiography or at autopsy; in these 2 instances, papillary muscle dysfunction was probably responsible for the mitral incompetence. In.the 2 remaining subjects, the origin of the acute regurgitation was unknown.

Results History : The natural histories are summarized in Table I. None of the patients had known cardiac murmurs before the development of the acute mitral incompetence. The onset of the murmur ranged from 2 weeks to 3 years before investigation (average 12 months). Only 2 subjects had had murmurs longer than 13 months. Symptoms of congestive heart failure closely coincided with the onset of the murmur. Dyspnea and evidence of left heart failure were always present, but in 2 patients ankle edema, recent weight gain and hepatomegaly indicated right heart failure at an early time in their course. Progressive clinical deterioration was not necessarily a feature ; on the contrary, the condition of all 8 patients initially improved considerably on medical management. Five patients eventually required surgical repair of the mitral valve within 2 to 24 months after their initial symptoms (average 9 months). However, 3 subjects remained in improved condition for 6, 12 and 36 months and are being followed up medically.

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Physical examination : The jugular venous pulse showed an abnormally tall a wave in 4 patients and a mild elevation of mean venous pressure in 3. On precordial palpation there was a prominent left ventricular impulse in 6 of the 8 subjects. A conspicuous right ventricular impulse was present in 4 cases. In no instance could we detect anterior left parasternal movement related to systolic expansion of the left atrium. There was an TABLE II Hemodynamic Data LV Pressure

Mean

Systolic

EndDiastolic

PA Systolic Pressure (mm Hg)

LA Pressure Case no.

(mm Hg)

(mm hg) V Wave

Cardiac Index (liters/mitt per m*)

1 2 3 4 5 6 7 8

70 33 58 34 48 50 40 (3;:5)

30 13 25 18 23 18 20 32

100 135 123 80 130 115 120 97

25 20 20 19 21 15 13 24

65 35 80 33 60 65 45 65

1.7 2.3 1.3 2.7 2.6 4.0 1.8 2.0

Mean

48

22

113

20

56

2.3

LA = left atrial;

LV = left ventricular;

PA = pulmonary

arterial.

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Figure 1. Two

phonocardiograms in the same patient with a ruptured chordae tendineae (Case 4). Left, findings at medium frequency (ZOO Hz); right, lower frequency findings (100 Hz). The murmur is holosystolic but reaches a peak in early systole and diminishes in late systole. Diastolic filling sounds (VDG and ADG) are well seen on lower frequency tracing. A = aortic valve closure sound; ADG = atrial diastolic gallop; P II pulmonic valve closure sound; S, = first heart sound: S2 = second heart sound; 2nd L.I.C.S. = second left intercostal space; VDG = ventricular diastolic gallop.

Figure 2.

Phonocardiograms of the 4 patients with ruptured chordae tendineae (from left to right, Cases 3, 4, 2 and 1). The murmurs all extend to the aortic closure sound (A). In all cases the intensity of the murmur in late systole is much less than in early or mid-systole. Tracings are taken at medium frequency (200 Hz) so that the lower pitched filling sounds are not recorded. A = aortic valve closure sound.

apical systolic thrill in 6 patients and a basal thrill in 1 (Case 7). An apical systolic murmur with a late systohc decrease was consistently present (Fig. 1 and 2). Although phonocardiograms showed the murmur to be holosystolic, the late systolic vibrations were often relatively inconspicuous and occasionally not appreciated with a stethoscope. Under these circumstances, the auscultatorg impression was that of an early and mid svstolic crescendo-decrescendo murmur finishing before the second heart sound. Such was the case in the single patient (Case 8) in whom a phonocardiogram was not taken. In this same patient, the murmur was relatively soft (grade Z/6). As a rule, however, the murmur was loud and rough, grade 4/6. In 6 of the 8 patients there was prominent radiation to the base; only 2 had radiation to the left axilla. In 6 of the subjects, there was evidence of pulmonary hypertension, as manifested by a large jugular venous a wave, a right ventricular impulse or a loud pulmonary closure sound, singly or in combination. Five of these patients had definitely increased pulmonary closure sounds. The 2 subjects without signs of pulmonary hypertension had large chests with increased anteroposterior thoracic dimensions which probably masked the findings. Third heart sounds were heard and reported in all 8 patients, and atria1 sounds were heard in 6. Atria1 sounds were recorded in the 2 patients in whom these events were not heard.

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Radiography : The cardiac X-ray films (Fig. 3 and 4) showed moderate left ventricular enlargement in ‘7 instances. The 1 patient without enlargement of the left ventricle had ruptured chordae tendineae of 2 months’ duration (Case 4). It was noteworthy that the left atrium was either normal or at best mildly enlarged in 7 of the 8 patients ; in only 1 instance was the dilatation conspicuous (Case 3). : Sinus rhythm was the rule Electrocardiogram without exception. Six patients had P wave durations of at least 0.12 second (3 had diphasic P waves in lead V, in which the negative component was at least 1 mm deep). The only electrocardiogram that exhibited broad bifid “p mitrale” P waves was from the patient who had left atria1 dilatation on X-ray film (Case 3) and a 13 month history of a murmur. Voltage criteria for left ventricular hypertrophy were present in only 2 instances.? Nonspecific S-T segment and T wave abnormalities were consistently found, but all patients were receiving digitalis. Cardiac catheterization: Hemodynamic data are summarized in Table II. Left atria1 a waves averaged 21 mm Hg (range 16 to 30). V waves averaged 48 mm Hg (range 33 to 70), and the mean left atria1 pressure averaged 22 mm Hg (range 10 to 32) (Fig. 5). Left ventricular systolic pressure averaged 113 mm Hg (range 97 to 135). End-diastolic pressure in the left ventricle averaged 20 mm Hg (range 13 to 25 ). The average pulmonary

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Figure 3. Cardiac X-ray films of 4 patients with acute severe mitral regurgitation due to ruptured chordae tendineae (from left to right, Cases 1, 2, 3 and 4). Left ventricular enlargement is prominent in Cases 1, 2 and 3. The only patient demonstrating prominent left atrial enlargement was Patient 3.

Figure 4. Cardiac X-ray films of 4 patients with acute severe mitral regurgitation (from left to right, Cases 5, 6, 7 and 8). Patients 6 and 8 had coronary artery disease proved at coronary arteriography and at autopsy. In Cases 5 and 7 the origin is unknown. Left ventricular enlargement with little or no left atrial enlargement is the rule.

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Figure 5. The tracing reflects high pressures very time when left ventricular pressure.

tall V wave of the pulmonary capillary wedge the high left atrial pressure. Note that the in the atrium are limited to late systole, the the murmur is diminishing (Case 6). L.V. = pressure; PCW = pulmonary capillary wedge

arterial systolic pressure was 56 mm Hg (range 33 to 80). Cardiac index averaged 2.3 liters/min per mB (range 1.3 to 4, indicator-dilution technique). The left ventricular angiocardiograms in the 7 patients so studied showed marked mitral regurgitation.

Discussion Chronic mitral regurgitation: The clinical manifestations of chronic and acute mitral incompetence differ considerably. Chronic mitral regurgitation is common both in women and men and frequently begins after an episode of rheumatic fever.R It may start in adolescence or young adulthood, but the murmur is characteristically present for many years before heart failure occurs0 Normal sinus rhythm is frequently replaced by atria1 fibrillation as time goes on. The classic murmur is holosystolic with conspicuous vibrations going up to and occasionally just beyond the aortic component of the second heart sound.“,“’ The murmur is relatively pure and blowing and generally radiates

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Figure 6. Left panel shows a typical left atrial pressure pulse compared to the brachial artery pressure in ruptured chordae tendineae. Right panel shows an intracardiac phonocardiogram (top line) compared to the chest wall apex phonocardiogram (second line). Although the murmur diminishes in late systole on the chest wall, it is easily heard at that time within the left atrium (Case 1). B.A. = brachial arterial pressure; L.A. zz left atrial pressure; LA. i-c = left atrial intracardiac phonocardiogram.

the axilla. A third heart sound is almost always present, but atria1 sounds are exceptional. The chest radiograph typically shows conspicuous enlargement of the left atrium, and the electrocardiogram exhibits “p mitrale” or atria1 fibrillation. Left ventricular enlargement may be present on X-ray examination and left ventricular hypertrophy on the electrocardiogram. Clinical signs of pulmonary hypertension are generally relatively unimpressive!’ since elevations in the level of pulmonary arterial pressure tend to be mild or moderate.x In the few cases in which marked pulmonary hypertension develops, the left atrium is always appreciably enlarged.R Acute mitral regurgitation: The clinical picture of acute severe mitral incompetence is in distinct contrast (Table III), Older men predominate and cardiac failure begins with or shortly after the onset of the murmur. Sinus rhythm is the rule. The characteristic murmur is an apical systolic murmur with a late systolic decrease. The murmur is usually loud and rough and commonly radiates toward the base rather than the axilla. The basal to

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radiation of the murmur together with the decrease in late systolic vibrations often results in a mistaken diagnosis of aortic stenosis.11-15 Third heart sounds are present but, in addition, atrial sounds and presystolic distension of the left ventricle are almost uniformly present as well. Clinical signs of pulmonary hypertension are frequent, as evidenced by a prominent jugular venous a wave, a right ventricular impulse and/or a loud sound of pulmonary valve closure. The chest radiograph typically shows little or no left atria1 enlargement, and the electrocardiogram exhibits sinus rhythm without “p mitrale.” It is precisely because the left atrium does not significantly dilate that most of the unique features of acute severe mitral incompetence develop. The powerful regurgitant jet into a small undistended left atrium results in extraordinarily high V waves and rather marked pulmonary hypertension. Presystolic distension of the left ventricle and the accompanying atria1 sound are peculiar to this form of mitral incompetence and are due to forceful contractions of the small but relatively thick wall of the left atrium.’ The systolic murmur and its radiation: A hallmark of acute severe mitral incompetence is the characteristic apical systolic murmur that diminishes considerably before the second heart sound. The mechanism responsible for the configuration of this murmur was proposed by Sutton and Craige,” and our observations support their views. The left atria1 pressure (V) wave rises to such heights in late systole (Fig. 6) that regurgitation diminishes in late systole and the murmur correspondingly decreases. Occasionally, the left atria1 V wave reaches the left ventricular pressure in late systole, as in the case of Sutton and Craige; under these circumstances the murmur ends before the second heart sound. In 1 of our patients, the auscultatory impression was that of a crescendodecrescendo systolic murmur that ended before aortic closure. In the 7 other patients, phonocardiograms showed that the murmur diminished in late systole but was truly holosystolic with soft vibrations going up to the second heart sound. Unusual patterns of murmur radiation have been reported in the past with “jet lesions” of mitral incompetence.11v14J5 It has been proposed that the direction of the jet depends to some extent upon which mitral leaflet is incompetent.1° According to this view, a posterior leaflet insufficiency may direct the jet forward and medially toward the atria1 septum and aortic root; the accompanying murmur would be heard well at the base of the heart and even into the neck. Anterior leaflet insufficiency may direct the jet laterally and posteriorly against the free wall of the left atrium ; the murmur would then be heard in the axilla and back. Two of our patients had posterior leaflet incompetence due to ruptured chordae tendineae

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TABLE

MITRAL

INSUFFICIENCY

III

Comparison

of Acute and Chronic Severe Mitral Chronic

Sex Age at onset History of murmur Natural history

Rhythm

Murmur

Third heart sound Atrial sound Left atrial size Pulmonary hypertension

Both men and women Adolescence and young adulthood Many years Heart failure occurs after long history of of murmur Atrial fibrillation (usual): sinus rhythm (less common) Holosystolic blowing apical murmur radiating toward axilla

Insufficiency Acute

Predominantly

in men

UsuaHy over 45 years old Recent onset Heart failure begins with onset of murmur Sinus rhythm

(usual)

Holosystolic, loud, rough murmur decreasing in late systole. Often radiating to base; confused with aortic stenosis

Present Absent Appreciably enlarged, sometimes huge

Present Present Normal or mildly enlarged

Mild-to-moderate

Mild-to-severe

which were proved at surgery. In both, the murmur radiated to the base. In 3 other patients, the defect was in the anterior leaflet; none of them had radiation to the back or axilla, but in 1 there was radiation to the base. In 3 patients, a thrill could be felt along the shaft of the transseptal catheter as it engaged the atria1 septum. One of these patients had posterior leaflet incompetence, but in 2 the anterior leaflet was incompetent. These observations do not confirm a predictable relationship between the direction of radiation of the regurgitant murmur and a particular leaflet. Clinical course: The severe degree of mitral incompetence was tolerated surprisingly well. Progressive, intractable heart failure did not necessarily result from the acute incompetence. All 8 patients initially experienced various degrees of improvement on medical management. Three are still being managed medically 6, 12 and 36 months after their illnesses began. Five came to surgery because of recurrent heart failure after initial improvement that lasted from 2 to 24 months. It has been suggested that the pericardium might temporarily protect against pulmonary edema in acute severe mitral incompetence by restricting systemic venous return. Hemodynamic data collected within 3 months of onset of the disease have shown that the diastolic pressures in all 4 cardiac chambers tend to approximate each other, much like the findings in constrictive pericarditis.” In none of our cases was this so. Even

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the 2 subjects who had ruptured chordae tendineae just 1 and 2 months before evaluation did not demonstrate it. Anatomic basis of regurgitation: Mitral regurgitation may be due to a defect in any one of the component parts of the mitral valve apparatus. These parts consist of the leaflets themselves, the fibrous valve ring and the suspensory apparatus of the valve, namely, the chordae tendineae, the papillary muscles and that portion of the left ventricle from which the papillary muscles arise. Insufficiency originating in the leaflets themselves is usually caused by rheumatic fever early in life and is generally a slowly progressive process with scarring and retraction of the valve tissue over many years. Mitral regurgitation caused by “dilatation of the ring” is probably uncommon since the ring is a tough fibrous structure that is not easily stretched. The mitral insufficiency associated with ventricular enlargement is usually due to the in-

creased longitudinal or lateral dimension of the ventricle with malfunction of the papilIary muscle-chordal support; stretching of the mitral ring probably plays relatively little part.lR Mitral regurgitation that begins after age 40-“maturity onset” mitral regurgitation-is far more likely to be due to a defect in the slcspenso?y apparatus of the valve than to an abnormality in the valve substance or valve ring. This variety of disease is the type represented by the 8 patients in this report. These disorders can be due to ruptured chordae tendineae (spontaneous rupture, endocarditis, trauma or avulsion from the papillary muscle head) or to disease of the papillary muscle’” (papillary muscle dysfunction, ruptured papillary muscle or ventricular dysfunction at the base of the papillary muscle attachment). Diseases of the suspensory apparatus typically began in adulthood; they are of sudden onset and represent the most common cause of “maturity onset” mitral insufficiency.

References E, Morrow AG: Acute severe 1. Roberts WC, Braunwald mitral regurgitation secondary to ruptured chordae tendineae. Circulation 33:58-70, 1966 Raftery EB, Oakley CM, Goodwin JF: Acute subvalvular mitral incompetence. Lancet 2:360-365, 1966 Clinical signs of severe acute Sutton GC, Craige E: mitral regurgitation. Amer J Cardiol 20:141-144, 1967 Auger P, Wigle ED: Sudden, severe mitral insufficiency. Canad Med Ass J 96:1493-1503, 1967 Selzer A, Kelly JJ Jr, Vannitamby M, et al: The syndrome of mitral insufficiency due to isolated rupture of the chordae tendineae. Amer J Med 43:822-836. 1967 EB: Acute mitral in6. Raphael MJ, Steiner RE, Raftety competence. Clin Radio1 18:126-136, 1967 The ventricular complex in left 7. Sokolow M, Lyon TP: ventricular hypertrophy as obtained by unipolar preAmer Heart J 37:161-186, cordial and limb leads. 1949 E, Morrow AG: Clinical and hemoa. Ross J Jr, Braunwald dynamic observations in pure mitral insufficiency. Amer J-Cardiol 2:11-23, 1958 Brit Heart 9. Brieden W. Leatham A: Mitral incomoetence. J 15:55-73, 1953 Auscultation of the heart. Lancet 2:75710. Leatham A: 765, 1958

11. Osmundson PJ, Callahan JA, Edwards JE: Mitral insufficiency from ruptured chordae tendineae simulating aortic stenosis. Staff Meeting Mayo Clin 33:235-246, 1958 JR: Mitral insufficiency due to rupture of 12. Thomas chordae tendineae simulating aortic stenosis. Amer Heart J 71:112-117, 1966 13. Sleeper JC, Orgain ES, McIntosh HD: Mitral insufficiency simulating aortic stenosis. Circulation 26:428-433, 1962 14. Miller R Jr, Pearson RJ Jr: Mitral insufficiency simulating aortic stenosis. New Eng J Med 260:1210-1213, 1959 15. Shapiro HA, Weiss DR: Mitral insufficiency due to ruptured chordae tendineae simulating aortic stenosis. New Eng J Med 261:272-276, 1959 JE, Burchell HB: 16. Edwards Endocardial and intimal lesions (jet impact) as possible sites of origin of murmurs. Circulation l&946-960, 1958 HJ: 17. Bartle SH, Hermann Acute mitral regurgitation in man. Circulation 36:839-851, 1967 of mitral insufficiency. ia. Levy MJ, Edwards JE: Anatomy Progr Cardiovasc Dis 5:119-144, 1962 19. Burch GE, DePasquale NP, Phillips JH: Clinical manifestations of papillary muscle dysfunction. Arch Intern Med (Chicago) 112:112-117, 1963

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