Results in 291 Cases*
RIOR to the development
bypass, the only
procedure. in the
use of transventricular factors
of the operative
dilators.’ an evaluation
to be used
Case Material: The records of the 294 patients undergoing closed mitral commissurotomy at the Mayo Clinic between July 1, 1960, and July 1, 1964, were revie1ved.t July 1960 was chosen as the starting date for this series because it was about this time that we began to use the transventricular dilator in all patients except those whose valves opened freely with digital pressure. Three patients were found at exploration to have mitral insufficiency and minimal stenosis and were dropped from this study. Of the 291 patients studied, 258 had not undergone previous surgery to the mitral valve (primary cases) and 33 had had surgery (secondary cases). ‘The ratio of female to male patients was 3: 1. There were 119 patients in class II (New York Heart Association Classification), 152 in class III and 20 in class IV. Information regarding regurgitation, mobility of the valve leaflets and the opening obtained was recorded by the surgeon at the time of exploration. After opening the valve, he also estimated creation or increase of regurgitation by means of the exploring t Some of these patients were operated F. H. Ellis, Jr., or by Dr. D. C. McGoon.
upon by Dr.
* From Rochester,
the Section Minn.
VOLUME 17, JUNE 1966
finger after hemodynamics had become stable. A Tubbs or Gerbode transventricular dilator was used in 90 per cent of the patients. In those remaining, an optimal valve opening was easily obtained by use of the finger alone. During this period an attempt was made to select for operation those patients in whom the valve would be amenable to a closed procedure. Patients with heavily calcified, immobile valves were considered candidates for valve rciJl;icement,” as were those with associated significant mitral valve incompetence or disease of multiple valves. A previous commissurotomy or a history of embolic phenomena was not considered a contraindication to closed mitral commissurotomy. Evaluation of Results: The apparent initial effectiveness of the commissurotomy was judged from the operative report. In the recent portion of the series the dilator usually was opened to 4.0 cm., and thus most patients could be considered to have a maximal opening. In the earlier cases, this was not always done if the valve was immobile, and in that event the opening was judged as poor. In a few patients the development of incompetence caused the surgeon to stop short of a maximal opening. The physiologic result depends, of course, not only on the vigor of the operative manipulation but also on the mobility of the leaflets and the associated incompetence. Thus, the surgeon judged mobility and degree of incompetence before and immediately after commissurotomy. Late results in 278 patients are available. The information was obtained by examination or by questionnaire sent after Jan. 1, 1965. The follow-up ranged from six months to five years and averaged 2.5 years. The result was termed good when the patient, at last report, was at least one class better than before the operation, or if he was still significantly improved over his preoperative status, even though he was not as well at last evaluation as he was one year after operation. Most patients with good results were in class I or II, having either no symptoms or mild ones and working regularly. The result was considered poor when the patient (a) died after
M.D. and JOHN
1960-1961* Hospital Total Deaths Cases No. y0 Primary Secondary Total * Interval
70 13 83
1 2 3
TABLE I After Closed Mitral Commissurotomy
1961-1962* Hospital Deaths Total Cases No. y0
1.4 15.4 3.6
78 10 88
3 1 4
1962-1963* Hospital Total Deaths Cases No. y0
3.8 10.0 4.5
refers to July 1 of one year to July
56 7 63
0 1 1
July 1960 to July 1964 1963-1964* Hospital Total Deaths Cases No. ‘%
0.0 14.2 1.6
54 3 57
0 2 2
RESULTS Mortality (Table I): The over-all hospital death rate was 3.4 per cent: 1.5 for primary In the cases and 18.2 for secondary cases. last 150 primary cases there has been one death. Autopsy was performed in 8 of the 10 patients who died. Causes of death are tabulated in Table II. In the 4 patients who died because of a probably inadequate opening of the valve, the transventricular dilator had been used but probably with less vigor than would now be employed. All had nonpliable leaflets, and all died with pulmonary congestion within the first seven postoperative days. Autopsy was performed in 2 of the 3 patients who died presumably from surgically induced regurgitation, and in each, the anterior leaflet had been torn rather than the commissures opened.”
258 33 291
4 6 10
1.5 18.2 3.4
One of the two died in spite of insertion of a mitral valve prosthesis at the same thoracotomy. The patient with severe coronary artery disease had intractable ventricular fibrillation during surgery, and at autopsy a myocardial infarction of recent origin was found. The one fatal arterial embolism involved the superior mesenteric artery and probably occurred during surgery. Ajparent Efectiueness of Commissurotomy: In 21 of the 291 cases (7y0), a poor opening probably had been obtained. In 48 patients of the series, it was known preoperatively that calcification of the mitral valve was present. Of the 48, 22 patients had no opening snap;4 in 8 of the 22 the valve was not opened satisfactorily. Twenty-six patients with a calcified valve exhibited an opening snap, and in only 1 of them was the opening considered by the surgeon to be unsatisfactory. Additionally, 41 patients were found at surgery to have some calcification of the valve, although it had not been identified before operation. In only 2 of these did surgery indicate a poor opening of the valve. Enough data were gathered from the operitive notes on 267 patients to allow an estimate of mobility of the leaflets (Table III). A
Causes of Hospital Mortality After Closed Mitral Commissurotomy
Probable inadequate opening Surgically induced regurgitation Hemorrhage Severe associated coronary artery disease Arterial embolus
0.0 66.6 3.5
1 of following year.
leaving the hospital, (b) underwent subsequent surgery to the mitral valve, (c) failed to show improvement at any time after commissurotomy, or (d) showed an initial improvement but subsequently deteriorated so that at the time of the last examination he was not improved or his condition was worse than it was preoperatively.
TABLE m Mobility
Total Hospital Deaths No. y0
Valve Leaflets as Determined Operation
Primary Cases No. ‘$& Good Fair Immobile Total
152 57 29 238
63.8 24.0 12.2 100.0
Secondary Cases No. % 12 11 6 29
41.4 38.0 20.6 100.0
164 68 35 267
61.4 25.5 13.1 100.0
TABLE v Late Results After Closed Mitral Commissurotomy (July 1960 to January 1965)
Increase in Incompetence After Closed Mitral Commissurotomy Increase in Incompetence After Commissurotomy None or Moderate Total or Severe Cases Mild
None or minimal
than did those in the primary
233 (91%) 29 (100%) 262 (92%)
(9%) O(O%) 24 (8%)
in Mitral Incompetence: The incompetence of the mitral valve was estimated before and after its opening in 286 of the patients Of these, 257 had little or no (Table IV). incompetence before the commissurotomy, and or severe inonly 24 (9%) had a moderate Three in incompetence afterward. crease patients appeared to have died from induced incompetence. In the 29 patients with moderate mitral regurgitation before the valve was manipulated surgically, the incompetence probably was not significantly increased by operation. Of the patients comprising the secondary group, incompetence after surgery was moderate or severely increased in 7 per cent. Arterial Emboli: Seven patients (2.4yc of the 291) showed evidence of postoperative arterial embolism. In 4 of them, no thrombus was noted in the atria1 appendage or atrium at surgery. Embolization seemed to have occurred during surgery in 4 patients and postoperatively (fifth, twelfth and thirteenth day, respectively) in 3 patients. Of the 291 patients, 52 (18%) had a history of preoperative arterial embolism. Only 25 per cent of these had thrombi in the left atrium or appendage at surgery, and 6 per cent (3 patients) had arterial embolism after surgery. traced, Late Results: Of the 278 patients results of surgery were good in 239 (86%) (Table v). Of these 239 patients, 21 (9%) have shown some deterioration after good initial improvement but were still significantly improved over their preoperative condition when last seen. Results of surgery were poor in 39 patients (14yc) (Table VI). This group includes (a) Increase
Type of Case All cases Poor opening achieved at surgery Severe incompetence at end of surgery Immobile valve (with or without calcification) Calcified valve+ and opening snap Calcified valve? and no opening snap
Result Good Poor No. ‘% No. %
* Excludes patients who died in hospital after surgery. t Includes only those in whom calcification was identified before operation by means of cardiac fluoroscopy.
5 who showed an initial improvement but then deteriorated and at last examination were not improved over their preoperative status: (b) 8 patients who obtained no benefit from the surgical procedure, either because of associated incompetence or because of an inadequate valvular opening; and (c) 11 patients who had a subsequent surgical procedure on the mitral valve 3 to 43 months (average 2 yr.) after the initial surgery. (In 4 of these patients, incompetence appeared to be the main lesion; in 5, stenosis and incompetence were present, and in 2 only stenosis was noted.) Fifteen patients are known to have died (7 apparently died suddenly although their cardiac status had significantly improved ; 5 showed progressive deterioration with return of symptoms prior to death; and 3 patients died of unrelated causes). When a poor valvular opening is obtained at TABLE VI Poor Results After Closed Mitral Commissurotomy (July 1960 to January 1964)
Late death Reoperation No improvement Deterioration Total
13 9 7 2 31
2 2 1 3 8
15 11 8 5 39
operation, naturally the result is poor (Table When the valve seems immobile to the v). surgeon, or when preoperatively it has been known to be calcified and immobile (no audible opening snap), about 40 per cent of patients have had a poor result from closed operation. In the small group of patients with calcified valves and an opening snap, only 12 per cent had a poor result during the period of follow-
sociated lesions. These conclusions are similar to those indicated by the analysis of an earlier group of patients from our clinic.7 There was no evident relation in the present study between preoperative electrocardiographic findings or heart size and prognosis after successful mitral commissurotomy.
Early and late results for 291 patients undergoing closed mitral commissurotomy, usually with transventricular dilator, between July 1, 1960, and July 1, 1964, are presented. The over-all hospital mortality rate was 3.4 per cent (1.5% for patients with no previous mitral valve surgery). Over-all incidence of operative or postoperative arterial embolism was 2.4 per cent (5y0 in patients with a history of arterial embolism). Causes of hospital deaths are listed. Tlrithin the period of follow-up, results of surgery were good in 86 per cent of patients traced. When the valve was immobile or significantly incompetent or when an optimal initial opening was not obtained at operation, the results were less good. In proper circumstances, good palliation at a low risk usually can be achieved by a closed operation.
The mortality following closed mitral commissurotomy in primary cases of this series has been low (1.5’%), an improvement over previously reported results.5 This improvement may be related largely to the use of open operation and valve replacement during the period under study in patients known to have heavily calcified or significantly incompetent mitral valves before operation. The improvement also may be related to the low incidence of arterial emboli (2.4%) occurring after operation-6 per cent’in patients with a history of arterial emboli. The minimal intra-atria1 manipulation allowed by use of the transventricular dilator, and the policy of never placing a clamp on the atria1 appendage, probably also contribute to the low incidence of emboli. The detailed analysis by Ellis and Harken of their 1,571 patients on follow-up for 12 years indicates that good palliation over many years often is achieved by closed commissurIn the context of the present status of otomy. valve replacement, the result of closed operation for mitral stenosis can be considered satisfactory when the patient has good palliation for at least two years after operation. It is unlikely, we believe, that any method of valvuloplasty or commissurotomy for mitral stenosis by open or closed technics will be curative, since the basic valvular scarring tends to increase with time, resulting in restenosis or incompetence. The low morbidity and mortality and the palliation achieved by closed mitral COI~Imissurotomy, usually with the transventricular dilator, recommend its use except when the mitral valve is immobile or significantly incompetent or when there are significant as-
REFERENCES 1. LOGAN, A. and TURNER, R.
Surgical treatment of mitral stenosis, with particular reference to the transventricular approach with a mechanical dilator. Lancet, 2: 874, 1959. 2. STARR, A. and EDWARDS, M. D. Mitral replacement: Clinical experience with a ball-valve prosthesis. Ann. Surg., 154: 726, 1961. 3. BJBRK,V. 0. and MALERS, E. Traumatic mitral insufficiency following transventricular dilatation for mitral stenosis. J. Thwack Surg., 46: 84, 1963. 4. LEATHAM, A. Auscultation of the heart. Lancet, 2: 702; 757, 1958. 5. JOHNSON, J. et al.
Present indication for the use of cardiopulmonary bypass in surgical treatment. of mitral stenosis. Ann. Surg., 157: 902, 1963. 6. ELLIS, L. B. and HARKEN, D. E. Closed valvnloplasty for mitral stenosis : A twelve-year follow-up of 1571 patients. New England J. Med., 270: 643, 1964. 7. ELLIS, F. H., JR., CONNOLLY,
D. C., KIRKLIN, J. W. and PARKER, R. L. Results of mitral commissurotomy: Follow-up three and one-half to seven years. Arch. Int. Med., 102: 928, 1958.
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