CVOL 68NOVEMBER

cAn Official Journalofthe tAmerican Heart cAssociation, Inc.

CLINICAL INVESTIGATION

Closed mitral valvotomy: early results and long-termfollow-up of 3724 consecutive patientsSTANLEY JOHN, M.S., M.S. (THOR.), F.A.C.C., F.A.C.S., F.A.M.S.,V. V. BASHI, M.S., M.CH. (THOR.), P. S. JAIRAJ, M.S., F.R.A.C.S., F.C.C.P.,S. MURALIDHARAN, M.S., M.CH. (THOR.), EDwIN RAVIKUMAR, M.S., M.CH. (THOR.),T. RAJARAJESWARI, M.B.B.S., S. KRISHNASWAMI, M.D., D.M., F.A.C.C.,I. P. SUKUMAR, D.M., F.R.C.P., F.A.C.C., F.A.M.S., AND

P. S. S. SUNDAR RAO, M.A., M.P.H., DR.P.H., F.S.S.

ABSTRACT Between 1956 and 1980 closed mitral valvotomies were performed in 3724 consecutivepatients (male:female ratio 1.1:1) with mitral stenoses. Their ages ranged from 6 to 69 years, with a

mean (SD) of 27.3 (9.3). Mitral stenosis in the younger age group is a unique condition and a greatmajority of these patients rapidly develop significant pulmonary hypertension and congestive cardiacfailure. In this study a large number of subjects belonged to functional class IV (41.5%). Hospitalmortality was 1.5% over the last 5 years. After valvotomy, 11 patients (0.3%) developed severe mitralregurgitation that made valve replacement necessary in the immediate postoperative period. Earlypostoperative embolism occurred in 0.4% of those who were in atrial fibrillation and had preoperativeanticoagulation whereas it occurred in 0.95% of those in sinus rhythm who had no anticoagulation.Late postoperative embolism occurred at a rate of 0.3 to 1.6 per 1000 patients per year over a 20 year

period. Rheumatic reactivity occurred at a rate of 1.3 to 2.2 per 1000 patients per year during the sameperiod. Rate of occurrence of restenosis varied from 4.2 to I 11.4 per 1000 patients per year between thefifth and fifteenth year of follow-up. Closed transventricular revalvotomy for restenosis was accom-

plished in 130 subjects with a 6.7% mortality. Excellent symptomatic improvement was evident in 86%of long-term survivors at the end of 15 years. Actuarial survival was 95%, 93.1%, 89.5%, and 84.2%at 6, 12, 18, and 24 years, respectively, after closed mitral valvotomy. Late deaths occurred in 4.3%.This study serves to highlight the excellent palliative effect of closed valvotomy for mitral stenosiswithout significant valvular calcification, substantial regurgitation, or significant associated valvularlesion.Circulation 68, No. 5, 891-896, 1983.

THE FIRST SUCCESSFUL closed mitral commissur-otomy was reported as early as 1923 by Cutler andLevine' and this ~was followed by a report by Souttar2 in1925. Three decades later this procedure was resur-

rected by Harken et al.,3 Bailey,4 and Baker et al.5 Atthe Department of Cardiothoracic Surgery of theChristian Medical College Hospital, Vellore, India,we have been carrying out closed mitral valvotomiessince 1956. This is a referral center and patients whounderwent closed mitral valvotomies over a 25 year

period serve as the basis for this report.

From the Departments of Cardiothoracic Surgery and Cardiology,Christian Medical College Hospital, Vellore, India.

Address for correspondence: Dr. Stanley John, Department of Car-diothoracic Surgery, C.M.C. Hospital, Vellore 632 004, India.

Received Jan. 5, 1983; revision accepted June 30, 1983.

Vol. 68, No. 5, November 1983

Material and methodsBetween 1956 and 1980 3724 subjects with mitral stenosis

underwent closed valvotomy. Their ages ranged from 6 to 69years, with a mean (SD) of 27.3 (9.3) years; 25% were less than20 years old and 40% were in their third decade. Male patientsconstituted 53.5% of the patient population.

Presenting symptoms and signs. Sixty-five percent of pa-tients had symptoms for less than 3 years and only 4% hadcomplaints beyond 10 years. A history of rheumatic fever wasobtained in 47.2% of patients, 14. 1% of whom had more thantwo episodes. Major preoperative clinical features are listed intable 1; 41.5% belonged to functional class IV, 57.5% to classIII, and the remaining 1% to class II. Four hundred sixty-nine(12.5%) were in atrial fibrillation and the remainder were in

sinus rhythm. The preoperative embolic episodes in those withsinus rhythm was 3. 1% and it was 11.3% in subjects with atrialfibrillation. A poor nutritional status was a striking feature inmany. Over 40% of our patients under 20 years old were in thesecond- or third-degree stage of malnutrition (less than 70%based on weight for age by American standards). Auscultatory

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TABLE 1Major preoperative clinical features

Clinical features %

Effort dyspnea 99.0Palpitation 80.0Right heart failure 72.0Paroxysmal nocturnal dyspnea 40.0Haemoptysis 30.0Preoperative embolic episode 4.2Atrial fibrillation 12.5Opening snap 98.2

findings of a sharp opening snap was evident in 93.5% and aloud first heart sound in 96.5%. Fluoroscopic examination re-vealed mild-to-moderate calcification in 15.3%. The other asso-ciated valvular lesions encountered were mild mitral regurgita-tion in 12.8%, mild aortic regurgitation in 15.5%, and tricuspidregurgitation (which was functional in almost every instance) in40.5%. Functional tricuspid regurgitation was considered to bepresent when the typical clinical features of tricuspid valveincompetence were present along with right ventricular failureand pulmonary arterial hypertension and when these signs be-came less marked, with total disappearance of some, after mitralvalvotomy. Patients were not considered for mitral valvotomy ifsignificant mitral regurgitation and heavy calcification wereobserved before surgery.

Electrocardiographic evidence of left ventricular hypertrophyin mitral stenosis was seen in 8.5% of patients, presumably theresult of associated aortic valve disease or thin chest walls,which were common. The criteria for left ventricular hyper-trophy was an R wave in V5 or V6 and an S wave in VI more than35 mm in height (for adults) or over 45 mm in height (forchildren).6

Cardiothoracic ratio ranged from 50% to 80%, with a mean(SD) of 56.2 (5.6). Pulmonary venous hypertension as definedby Braunwald was evident in 75% of patients.7 Although cardi-ac catheterization and angiocardiographic examination on a rou-tine basis is not feasible, these procedures were performed in214 subjects (including many young subjects) to quantitate thedegree of pulmonary hypertension and in other patients theywere used to document the degree of associated valvular lesionwhen it was deemed mandatory because of tight mitral stenosis.

Surgical considerations. A left anterolateral thoracotomythrough the fifth intercostal space has been the method of choicefor all those in sinus rhythm. A posterolateral incision wasroutinely used in all subjects with atrial fibrillation; this allowedaccess through the body of the atrium when the appendage wasshriveled and fibrosed.8 This approach was always used in pa-tients with restenosis of the mitral valve when a closed revalvot-omy was carried out.

Instrumental dilatation of the mitral valve was achieved inalmost all instances with the Tubbs transventricular dilator.Early in our experience, finger fracture of the mitral valve wasdone in 219 subjects. Postoperative ventilatory assistance wascarried out for at least 24 hr in those who belonged to class IVand had complicating pulmonary hypertension. It was extraor-dinary that 83.7% of subjects had a valve orifice of 0.5 cm orless, the measurement being judged by digital assessment.Follow-up. All patients at the time of discharge were pre-

scribed long-term chemoprophylaxis and were advised to reportat the end of 1 year to the outpatient department. Once every 3weeks chemoprophylaxis was achieved by the use of intramus-cular injections of 1.2 million U benzathine benzylpenicillin inthose weighing more than 27 kg and of 600,000 U in thoseweighing less than 27 kg. In less than 2% of the patients daily

sulfadiazine was used for chemoprophylaxis since penicillincould not be given due to problems of sensitization. Over 90%of the patients adhered to this regimen. Routine check-upincluded physical, x-ray, electrocardiographic, and echocardio-graphic examinations in the recent past. Following this, patientswere asked to come for periodic review at the end of 2 years andsubsequently at 5 year intervals. However, if symptoms re-curred, they were asked to report to us immediately. The assis-tance of referral physicians was also sought in getting the re-quired data. Those patients who failed to come in were sent aprinted questionnaire to be filled out and returned. Vigorousattempts were also made to locate the nonresponders with thehelp of a social worker who made personal visits. The follow-upperiod ranged from 1 to 24 years and the success offollow-up atvarious time intervals is depicted in table 2. In view of the factthat the patients treated hailed from remote corners of the coun-try and even from abroad, it was not possible to have a 100%response. However, it is remarkable that, as shown in this table,we were able to achieve over 70% follow-up at the end of 15years. A comparison between nonresponders at each follow-upperiod with those who responded revealed that the various clini-cal and other features were not significantly different.

Means, SDs, proportions, and their SEs were computed whennecessary. The incidence of various events and mortality were

expressed per 1000 patients per year. Actuarial survival rateswere computed by the method of Cutler and Ederer.9

ResultsThe hospital mortality (defined as death occurring

within 30 days after surgery) was 4.2% in class IV and3.6% in class III subjects, averaging 3.8% for thegroup as a whole. The list of causes of death given intable 3 indicates that the most common of these were

refractory cardiac failure and tachyarrhythmias or

bradyarrhythmias.A satisfactory surgical result was achieved in 98%

of patients. This was considered adequate or nearlynormal in our experience when the orifice admitted 11/2to 2 fingers or more. In 74 patients (2%) it was pre-

sumed that the valvotomy was incomplete. The com-

mon adverse features sometimes responsible for an

inadequate valvotomy were tough fibrotic valves, ex-

tensive subvalvar fusion, and dense calcification inad-vertently encountered at surgery. The outcome of val-votomy in each group, i.e., those with and withoutsharp opening snaps, loud first heart sounds, and calci-fication, is given in table 4. Nevertheless, the presence

TABLE 2Number and percent of patients available for follow-up at varioustime intervals

Years of Patients No. followedfollow-up at risk up %

1 3580 3561 99.55 2751 2587 94.010 1736 1422 81.915 892 639 72.020 or more 252 175 69.4

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PATHOPHYSIOLOGY AND NATURAL HISTORY-VALVULAR HEART DISEASE

TABLE 3Causes of hospital deaths

Cause No.

Refractory cardiac failure 66Arrhythmias 42Embolism 15Septicemia 7Renal failure 6Respiratory infection 3Gastrointestinal bleeding IPenicillin anaphylaxis I

of certain adverse features need not negate a successfulvalvotomy.A mild degree of postoperative mitral regurgitation

resulted in 18%, which we believe was not hemodyna-mically significant. Eleven subjects (incidence of0.3%) developed severe mitral regurgitation. Of these,seven underwent emergency valve replacement in theearly postoperative period and this resulted in onedeath. Four died without surgery. In the 12.8% ofpatients in whom a mild degree of regurgitation wasnoted before surgery, a successful valvotomy resultedin its disappearance in 47%. In only 8% did it increaseto regurgitation of a moderate degree.

Over the past decade, patients with mitral stenosisand complicating atrial fibrillation underwent a 3 weekanticoagulant regimen before surgery. In this group of265 patients the incidence of postoperative embolismwas 0.4%. Early in this series, in 204 subjects withatrial fibrillation who did not undergo the anticoagu-lant regimen, the occurrence of postoperative embo-lism was 6.2%. In patients who were in sinus rhythmthe overall incidence of postoperative embolism wasonly 0.95%.

Eighty patients had concomitant closed transventric-ular mitral and aortic valvotomies while four had triplevalvotomies (tricuspid valve included). In the presenceof associated tricuspid stenosis, closed combined mi-tral and tricuspid valvotomies were accomplished inthree patients. This will be the subject of a later report.

The functional status of patients at each stage offollow-up is illustrated in figure 1. In the 639 subjectswho were followed up for 15 years, clinical status datarevealed that 86% maintained an excellent or goodcondition. It is noteworthy that of 119 subjects whowere seen beyond 20 years, 27 were in functional classI and 53 in functional class II. Actuarial analysis by themethod of Cutler and Ederer9 indicates a good long-term survival, with 94.0%, 89.4%, 85.0%, and 78.3%alive at 6, 12, 18, and 24 years, respectively, withouthaving to undergo a second procedure (figure 2).

Vol. 68, No. 5, November 1983

The incidence of various events at different stages offollow-up is given in table 5. The occurrence of reste-nosis varied from 4.2 to 11.4 per 1000 patients per yearbetween the fifth and fifteenth year of follow-up. Theincidence of rheumatic reactivity was low and its oc-currence showed a progressive decline after the tenthyear. It is apparent from this study that besides theincidence of restenosis, incidence of other importantevents, such as rheumatic reactivity, embolic phenom-ena, and mitral regurgitation, did not show a positivecorrelation with time.One hundred and seventy-two patients underwent a

second operation on the mitral valve. Sixty-eight sub-jects who did not heed the advice to undergo anotheroperation died without having had it. It is relevant tomention that in 130 of these (ranging in age 13 to 59years; mean + SD, 31.9 + 8.8) closed transventricu-lar revalvotomies were carried out with an operativemortality of 6.7%. In 26 patients, mitral valve replace-ment was accomplished. The remainder are awaitingsurgery (table 6). Late deaths occurred in 4.3%, themost common cause being progressive cardiac failure.

DiscussionThere is a growing body of surgeons who support

open commissurotomy as the preferred surgical ap-proach for mitral stenosis. 11-4 The operative mortalityfor this procedure ranges from 1.5% to 10%.12 15 Atthis center, open valvotomy is the method of choice inthose with Lutembacher's syndrome,'6 massive leftatrial thrombus,17 and restenosis with atrial fibrillation.Houseman et al. 14 mentioned 16% occurrence of reste-nosis after an open procedure. Brewer'8 stated that an"open" operation frequently did not give a better re-sult than a "closed" procedure. The one deterrent toopen valvotomy that stands out is the fact that thenumber of valves that tend to be replaced varies from afigure as high as 44%11 to 28%.13 The tactile impres-sion in assessing function of the valve after closedTABLE 4Preoperative findings

AdequatePreoperative No. of valvotomy

findings cases (%)

Calcium + 574 94.0No calcium 3150 97.8Loud first heart soundYes 3585 98.1No 139 97.9

Sharp opening snapYes 3471 98.2No 242 95.7

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U'7~ 0 CLASS IV

> 60

'n 50

zw 40

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20

10

PRE OP 1 5 10 15 2(3724) ________________________

POST OP YEARS

No OFCASES FOLLOWED (3561) (2587) (1422) (639) (1 7

FIGURE 1. Functional status of patients at different stages of follow-up.

0O

75

mitral valvotomy is superior to that obtained during theopen procedure.The present study shows that in terms of safety,

efficacy, excellent long-term results, and low-cost ef-fectiveness, closed valvotomy remains the treatmentof choice as a palliative operation for mitral stenosis. Alarge number of subjects in the Vellore study were intheir third decade while other authors1' 19 have report-ed that a significant proportion of their subjects were inthe fifth decade of life. Furthermore, there is a prepon-

derance of men in our study as compared with otherlarge series.10' 19-24 Profound disability and chroniccongestive failure were observed in many patients andseveral were moribund at the time of surgery. A higherincidence of atrial fibrillation (63%), together with a

greater occurrence of postoperative embolism, have

90-

80-

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been recorded by other authors20' 25-28 as compared withthe 12.5% incidence of atrial fibrillation and low inci-

dence of postoperative embolism we observed. Var-ious authors0'° 9 25. 29, 30 have quoted mortality figuresranging from 1% to 8.7%. Ellis et al. ,3 in their reviewof 1000 patients, noted a mortality of 19% in class IVpatients. In this study the hospital mortality among1545 class IV patients was only 4.2%. The low inci-dence of severe postoperative mitral regurgitation(0.3%) is at variance with reports of others.32Even in those subjects with mild-to-moderate calci-

fication a favorable result was achieved in 94%.

Olinger et al.30 carried out closed valvotomies in 23

patients with calcific mitral stenosis. It is pertinent that

the use of a transventricular dilator in this procedure is

imperative and these authors believe that the occur-

2965

671

-1

Survivors after CMV

--- Survivors after CMV without

Isecond procedure

FIGURE 2. Actuarial survival curve after closed

mitral valvotomy.

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YEARS AFTER CM V

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CIRCULATION

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PATHOPHYSIOLOGY AND NATURAL HISTORY-VALVULAR HEART DISEASE

TABLE 5Incidence of various events (per 1000 patients/year) at different periods of follow-up

Years No. of Mitralof cases Mitral Rheumatic regurgi- Systemic Late

follow-up followed restenosis reactivity tation embolism deaths

1 3,564 0.0 1.6 4.2 0.3 1.75 2,643 4.2 2.2 5.5 0.2 3.410 1,473 8.1 1.7 3.5 0.3 3.515 670 11.4 1.8 4.7 0.6 3.420 or more 186 5.6 1.3 1.9 1.6 3.8

rence of significant regurgitation when this dilator is inuse is a dangerous hazard. In a finger fracture valvoto-my the force to open the valve is unidirectional and thismaneuver could result in the dislodgement of calcificemboli.

During the last decade the routine use of anticoagu-lants in subjects with mitral stenosis and atrial fibrilla-tion has resulted in a postoperative thromboembolicoccurrence rate of 0.4%, as contrasted with a figure of10% to 22% significant emboli observed by other au-thors. 11, 3336

The incidence of restenosis herein was low com-pared with figures varying from 50% to 10%.37' 38 Re-stenosis is not the result of an inadequate valvotomy,but of the inexorable progress of the fibrotic process;our results with this entity have been reported earli-er.39 41 It should be noted that a great majority of pa-tients in our series were in a younger age group ascompared with subjects in other studies and they there-fore had more pliable valves and were, in our opinion,excellent subjects for closed mitral valvotomy. Thefollow-up data in our study indicates that the peak timefor incidence of restenosis is about year 12, with agradual decline in its incidence thereafter. Schoe-vaerdts et al.42 stated that the tenth postoperative year

TABLE 6Details of reoperation

Performed Performedat at

this otherReoperation center centers Total

Closed revalvotomy 130 6 136Mitral valve replacement 26 2 28Open mitral valvotomy 5 - 5Open mitral and aortic

valvotomy 1 1Mitral and aortic valve

replacement 1 1Open mitral valvotomy and

aortic valve replacement 1Total 164 8 172

is the critical period when the need for reoperation isthe greatest, irrespective of whether the procedure wasopen or closed. Salerno et al.43 reported a 9.5% opera-tive mortality in those having a second closed valvoto-my, whereas it was 6.7% in our study.

Symptomatic improvement was sustained and actu-arial analysis revealed that 78.3% of patients werealive at the end of 24 years. In light of the excellentsymptomatic benefit - both early and long-term -obtainable with the transventricular dilator techniques,it seems logical to continue the use of mitral valvotomyin most cases of isolated mitral stenosis.

Our appreciation in a large measure goes to Mr. V. Nagarajanfor secretarial help. We also express our grateful thanks to thestaff of Medical Records Department and Biostatistics Depart-ment for their help and cooperation. Many others have givenmuch of their time and effort in compiling the data.

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stenosis: experimental observations and clinical notes concerningan operated case with recovery. Bost Med Surg J 188: 1023, 1923

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Krishnaswami, I P Sukumar and P S RaoS John, V V Bashi, P S Jairaj, S Muralidharan, E Ravikumar, T Rajarajeswari, S

patients.Closed mitral valvotomy: early results and long-term follow-up of 3724 consecutive

Print ISSN: 0009-7322. Online ISSN: 1524-4539 Copyright © 1983 American Heart Association, Inc. All rights reserved.

is published by the American Heart Association, 7272 Greenville Avenue, Dallas, TX 75231Circulation doi: 10.1161/01.CIR.68.5.891

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