e CRITICAL REVIEW The Murmurs of Mitral Regurgitation ECG Eduardo Moreyra, M.D., Bernard L. Segal, M.D., F.C.C.P., and Hideyo Shimada, M.D.

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1 e CRITICAL REVIEW The Murmurs of Mitral Regurgitation Eduardo Moreyra, M.D., Bernard L. Segal, M.D., F.C.C.P., and Hideyo Shimada, M.D.t n apical holosystolic murmur with radiation to A the axilla and back is the hallmark for the diagnosis of mitral regurgitation. l 2 In these patients, the presence of a third heart sound suggests that the incompetence is significant, and frequently this ventricular filling sound is followed by a short rumbling diastolic murmur owing to increased How across the mitral valve 2 3 (Fig 1). The purpose of this communication is to discuss other murmurs of mitral regurgitation which are less common. TIm EARLY SYSTOLIC MURMUR Patients with dominant mitral stenosis and mild or moderate mitral incompetence frequently have early decrescendo systolic murmurs which start with the first sound and terminate in midsystole (Fig 2). In our experience, selective left ventriculography in this type of patient demonstrates mild degree of mitral regurgitation. We have also noted the early systolic murmur in patients with solitary mitral stenosis (Fig 3). Surawicz et al have reported that these systolic murmurs occur in 48 percent of these patients," We do not have an appropriate explanation for the systolic munnur appearing in mitral stenosis alone. It has been suggested that in these patients minimal mitral incompetence is present but is not detected by left cine ventriculography. We conclude that often it is not possible by auscultation only, to differentiate solitary mitral stenosis from dominant mitral stenosis with mild mitral insufficiency. Fellow in Cardiology, Department of Medicine, Hahnemann Medical College and Hospital, Philadelphia, Pennsylvania. Assistant Head Cardiology Section, Associate Professor of Medicine, Hahnemann Medical College and Hospital, Philadelphia, Pennsylvania. ffellow in Cardiology, Department of Medicine, Hahnemann Medical College and Hospital, Philadelphia, Pennsylvania. TIm LATE SYSTOLIC MURMUR Most physicians now believe that the late apical systolic murmur sometimes preceded by a "nonejection click" is indicative of mild or moderate mitral regurgitation 6-8 (Fig 4,5). This murmur should not be confused with the holosystolic murmur composed of soft vibrations in early systole and a louder murmur at the end of the systole. Recently, several investigators have established the origin of the click and late systolic murmur to be in the mitral valve and subvalvular structures.6-8 Barlow et al 8 believe that a "non-ejection click denotes uneven distribution of tension in the chordal mechanism and that one or more chordae are ECG ---~ ,---- FIGURE 1. Multichannel phonocardiograms with simultaneous ECG and indirect carotid pulse (CAR) are taken from a patient with severe mitral regurgitation. High ( ), medium (MF) and low frequency (LF) filters are used. The apical systolic murmur (5M) is holosystolic, beginning with the first heart sound (51) and ending with the second sound (52)' A loud third heart sound (5 a) and short diastolic murmur (OM) are noted. 49

2 50 A MOREYRA ET AL FIGURE 2. Phonocardiograms taken from two patients with dominant mitral stenosis and mild mitral regurgitation. The systolic murmur (8M) of mitral rebux is early, beginning with the flrst heart sound (8 1 ) and ending in midsystole. An opening snap (08) and a diastolic murmur (DM) are noted. lengthened or are relatively longer than other 6 brosed chordae." In these conditions, sudden tensing of a chorda or the leaflet to which it is attached results in the click. Similarly, these authors suggest that the presence of late systolic murmurs are due to chordae which are lengthened (anatomically or functionally) or ruptured. In each case, the leaflet to which the affected chorda is attached prolapses abnormally into the left atrium during systole. In most of the cases reported, the posterior leaflet is involved and when the nonejection click is present, it is synchronous with maximal ballooning of the posterior mitral leaflet," This leaflet has chordae of the third order" which insert in the central portion of its ventricular surface'? and provide support to the leaflet. Any process leading to elongation or rupture of these chordae would permit the balloon , A!It "os : ,~. B.. s, Sa ~~ ~~LF~III."""""""'~ 1EC8 ~ ~ APU APIIC FicuBE 3. Phonocardiograms taken from two patients with solitary mitral stenosis. The early systolic munnur (SM) is noted. No mitral reflux was demonstrated by left cine ventriculography in these patients. ing of the posterior leaflet as shown experimentally by Stannard et aj.7 Once this process has started, it is probably progressive, producing stretching of the leaflet which becomes voluminous and puts greater strain on the chordae of the 6rst and second order. With progressive stretching of these chordae, mitral regurgitation develops.s and it is a self-perpetuating mechanism which may lead to more serious degrees of incompetence." This concept proposed by Barlow et al may explain how several etiologic factors (rheumatic valvulitis, myocardial and papillary muscle dysfunction, trauma leading to rupture of a chorda tendinea, bacterial endocarditis, Marfan's syndrome, idiopathic subaortic stenosis, mitral valve surgery, etc) involving the leaflets, chordae, papillary muscles or their combination could lead to ballooning of the posterior mitral leaflet and mitral regurgitation confined to late systole. Congenital weakness of the valve could explain. in some patients, the aneurysmal deformity of the posterior leaflet and the prolapse of this leaflet into the left atrium during systole Patients with the Marfan syndrome and prolapse of the posterior mitral leaflet have been reported.e.s In our experience, 50 patients with the late systolic murmur had a modest degree of mitral regurgitation (grade 1 or 2 out of 4) with the exception of one patient who had severe mitral incompetence (Fig 5). Subacute bacterial endocarditis,8.12 arrhythmias T 8 and even sudden deaths have been reported in patients with the late systolic murmur. These patients should be carefully followed and prophylactic antibiotics administered when indicated. MID-SYSTOUC MURMUR A mid-systolic murmur, diamond-shaped, has been described by Burch et aj13 and Phillips et aj14 DIS. CHEST, VOL. 55, NO. I, JANUARY 1969

3 MURMURS OF MITRAL REGURGITATION ~ ~-~ +\~~~~~*IJ L.F - t--j,.~vj~vrj~vj ~L ML 9Y MII+ APEX in the patient with mechanical dysfunction of the papillary muscles due to myocardial infarction or ischemia. In this condition, the ischemic papillary muscle fails to shorten during ventricular ejection resulting in mitral incompetence. This murmur hegins after isovolumetric contraction and is well heard at the apex with radiation to the left axilla and sometimes to the aortic area. 14 The crescendo-decrescendo characteristic of this murmur is probably related to the tendency of the valve to increase its incompetence in midsystole reflecting the changes in left ventricular pressure." Scarring of a papillary muscle may also be expected to produce a holosystolic murmur if the ~ '_, '. '.. i H' ~ ~'.'l "~. - t'. MF S'CSMSz S,CSMSt ~_~i~~- '~~~'l\~~~~'~r----\\v--'r ECG --.I\.,-- -.!I..r---...JI..,-.J~ mitral incompetence begins with the first heart sound (during isovolumetric contraction of the left ventricle). A similar situation would occur if a normally contracting papillary muscle is implanted in an area of ventricular aneurysm.p The murmur of papillary muscle dysfunction may become louder during transient episodes of papillary muscle ischernia.v' Chordal rupture leads to different degrees of mitral incompetence; the apical murmur is usually FIGtJRB 4. The late systolic murmur (SM) begins in midsystole and ends with the second heart sound (S2)' A nonejection click (C) in midsysto}e introduces this murmur. Mild mitral regurgitation (grade 1) was demonstrated by cine ventriculography , ,..- s' II It.' I ~...---t.j;, ~ MF 51! 51 S, Sa s, Sa ~~~v,-r~~r-t~- LF ~\r'-';' ~""tl ~~ ECG WI 3+ I.e. -44Y. APEX FIGURE 5. The late systolic murmur (SM) follows a nonejection click (C) and ends with the second heart sound (S2)' This was the only example of our series of 50 patients with late systolic murmurs who had severe mitral regurgitation (grade 3) demonstrated by left ventricular cineangiography. FIGURE 6. Phonocardiograms taken from a patient with congestive failure due to cardiomyopathy. Mitral regurgitation ( grade 2) was demonstrated by cineangiography. Systolic murmurs are absent, Note the pulsus altemans in the carotid recording and the alternating intensity of the third heart sound (Sa)'

4 52.. lie ~H,~IV-1I\\o,."'--"'-~~I~.-.JU.-~ LF Eee '-"""""" '-/"""" FIGURE 7. Phonocardiograms taken from a patient with cardiomyopathy and congestive heart failure. Mild mitral regurgitation (grade 1) was demonstrated by left ventricular cineangiography. A systolic murmur is not present, but a short diastolic rumbling murmur (DM) is clearly demonstrated in this record, holosystolic. This murmur frequently radiates to the basal areas of the precordium and even to the neck vessels, where it assumes a crescendo-decrescendo configuration and is sometimes confused with the murmur of aortic stenosis.lll.1 6 The propagation of the murmur to the base of the heart should suggest rupture of a chorda attached to the posterior mitral leaflet. If the ruptured chorda belongs to the anterior mitral leaflet, the radiation of the murmur is generally toward the back.'t The transmission of the apical murmur to the base of the heart and neck vessels is due to the regurgitant jet directed to the interatrial septum and adjacent root of the aorta. I S In the cases with ruptured chordae of the anterior mitral leaflet, the jet is directed toward the posterior wall of the left atrium adjacent to the spine. This favors propagation of the murmur to the cervical and lumbar spine l 9 and even to the vertex of the head. 2O A thrill palpated over the middle thoracic spine and slightly to the left of it has been described in patients with ruptured chordae tendineae of the anterior mitral leaflet.s! SILENT MITRAL REcuRGlTATION Silent mitral incompetence has rarely been reported in rheumatic heart disease. 22 2s When present, it is usually associated with mitral stenosis. In the last year, we have studied three patients with congestive cardiomyopathy and no systolic murmur. Two of these patients had ventricular gallops (Fig. 6) and the third patient had a third heart MOREYRA ET AL sound followed by a short and loud rumbling murmur at the apex (Fig. 7). The first two patients had moderate mitral regurgitation (grade 2 out of 4), and the third had only mild mitral incompetence. These three patients demonstrated severe congestive failure which may be responsible for attenuation of the murmur. Although intracardiac phonocardiograms were not obtained, it is possible that the systolic murmur was present in the left atrium and absent on the surface of the chest. The How murmur in the third patient is even more difficult to explain in view of the modest degree of mitral regurgitation and the absence of a systolic murmur. SUMMARY Not all murmurs of mitral regurgitation are holosystolic. Occasionally, the patient with mitral reflux will demonstrate an early systolic murmur, a late systolic murmur or a mid-systolic murmur. Rarely, a systolic murmur is absent. We have also described a patient with silent mitral regurgitation and a short diastolic rumbling murmur. fu:ferences 1 LEATHAM, A.: Auscultation of the heart. Lancet, 2: 703, SEGAL, B. L., AND KALMAN, P.: Bedside diagnosis of heart disease--analysis of murmurs, Progr. CardiovaBc. Dis., 6:581, HUMPHRIES, J. 0.: Diagnosis of pure mitral regurgitation. The Theory and Practice of Auscultation, Edited by B. L. Segal. F. A. Davis Co., Philadelphia, SURAWICZ, B., MERCER, C., CHLEBus, H., REEVES, J. T., AND SPENCER, F. C.: Role of the phonocardiogram in evaluation of the severity of mitral stenosis and detection of associated valvular lesions, Circulation, 34:795, LEIGHTON, R. F., PAGE, W. L., GooDWIN, R. S., MOLNAR, W., WOOLEY. C. F., AND RYAN, J. M.: Mild mitral regurgitation-its characterization by intracardiac phonocardiography and pharmacologic responses, Amer. ]. Med., 41:168, CRILEY, J. M., LEWIS, K. B., HUMPHRIES, J. 0., AND Ross, R. S.: Prolapse of the mitral valve. Clinical and cineangiographic findings, Brit. Heart t.. 28:488, STANNARD, Moo SLOMAN, J. G., HARE, W. S. C., AND GoBLE, A. J.: Prolapse of the posterior leaflet of the mitral valve. A clinical, familial and cineangiographic study, Brit. Heart ].,29:71, BARLOW, J. B., BOSMAN, C. K., POCOCK, W. A., AND MARCHAND, P.: Late systolic murmurs and non-ejection ("mid-late; systolic clicks. An analysis of 90 patients, Brit. Heart ].,30: CHIECHI, M. A., LEES, W. M., AND THOMPSON, R.: Functional anatomy of the normal mitral valve, ]. Thorac. Surg., 32:378, ]0 Do PLESSIS, L. A., AND MARCHAND, P.: The anatomy of the mitral valve and its associated structures, Thorax, 19:2'21, 1964.

5 MURMURS OF MITRAL REGURGITATION 11 LUCARDIE, S. M., AND DuJuu:R, D.: The late systolic murmur, Arch. KreislauDorsch, 53:174, LINHART, J. W., AND TAYLOR, W. J.: The late apical systolic murmur. Clinical, hemodynamic and anglographic observations, Amer. I. Cardiol., 18:164, BURCH, G. E., DE PASQUALE, N. P., AND PmLLIPS, J. H.: Clinical manifestations of papillary muscle dysfunction, Arch. Intern. Med., 112:158, PmLLIPS, J. H., BURCH, G. E., AND DE PASQUALE, N. P.: The syndrome of papillary muscle dysfunction. Its clinical recognition, Ann. Intern. Med., 59:508, SHAPIRO, H. A., AND WEISS, D. R: Mitral insufficiency due to ruptured chordae tendineae stimulating aortic stenosis, New Eng. I. Med., 261:272, MILLER, R, AND PEARsoN, R J.: Mitral insufficiency simulating aortic stenosis. Report of an unusual manifestation of Marfan's syndrome, New Eng. I. Med., 260:1210, CmLnRESS, R. H., MAROON, J. C., AND GENOVESE, P. D.: Mitral insufficiency secondary to ruptured chordae tendineae, Ann. Intern. Med., 65:232, OSMUNDSON, P. J., CALLAHAN, J. A., AND EOWAJlD8, J. K: Mitral insufficiency from ruptured chordae tmtdineae simulating aortic stenosis, Proc. Staff Meetit1g, MallO Clinic, 33:235, PERLaFF, J. Ie., AND HARVEY, W. P.: Auscultatory and phonocardiographic manifestations of pure mitral regurgitation, Prog. Cardi0008. DII., 5:172, STEINMETL, G. P., ANDERSON, A. M., CoBB, L. A., BRUCE, R. A. AND MERENDINO, Ie. A.: Posteromedial annuloplasty for acquired mitral insufficiency-methods and results, Progr. Cardiovasc. Dis., 5:280, GIULIANI, E. R: Mitral valve incompetence due to flail anterior leaflet. A new physical sign, Amer. I. Cardiol., 20:784, ARAVANIS, C.: Silent mitral insufficiency, Amer. Hem't I., 70:620, Lrsors, W., SEGAL, B. L., KAsPAR, A. J., KASPARIAN, H., AND NOVA(%, P.: Silent rheumatic valvular heart disease. Dis. Chest, 49:362, Reprint requests: Dr. Segal, 230 North Broad, Philadelphia Each year the College offers undergraduate medical students throughout the world the opportunity to submit manuscripts on any phase of the diagnosis and treatment of cardiovascular or pulmonary disease, in open competition. Medical students wishing to enter the 1969 AHred A. Richman Essay Contest of the American College of Chest Physicians should observe the following rules: 1) Complete application form in duplicate, have original copy signed by the dean of the medical school, and return original copy at once to the American College of Chest Physicians, 112 East Chestnut Street, Chicago, Illinois ) Five copies of the manuscript, typewritten in English (double spaced) must be submitted to the American College of Chest Physicians offices in Chicago not later than April 15, ) The length of manuscripts is optional; words suggested. 4) The only means of identification of the author shall be a motto or other device on the title page. AMERICAN COLLEGE OF CHEST PHYSICIANS 1969 ALFRED A. RICHMAN ESSAY CONTEST A sealed envelope bearing the same motto on the 'outside and enclosing the name and address of the author must accompany the essay. (Motto may be a word or brief phrase which has a signibcant meaning to the author.) The First Prize will be $500; Second Prize wid be $300; Third Prize will be $200. Each winner wid also receive a certificate of merit. A trophy, inscn1>ed with the name of the First Prize winner and the name of his school will be awarded to the winner's school. The winning contn"butions wid be selected by a committee of chest specialists at the 35th Annual Meeting of the American College of Chest Physicians to be held in Chicago, Illinois in October, All manuscripts become the property of the American College of Chest Physicians and may be considered for publication in the College journal. It is suggested that applicants study the format of the College journal, DISEASES OF THE CHEST, to guide them in preparing the essay. A copy wid be sent on request.