A Clinical Study of 1,000 Consecutive Cases of Mitral Stenosis Two to Nine Years after Mitral Valvuloplasty

Abstract

A study is presented of 1,000 cases of predominant mitral stenosis operated by valvuloplasty between 1949 and 1956. It is shown that the survival of these patients is better than would have been expected under medical management.

Incidence of systemic embolism before and after mitral valvotomy

“…The figure of 26% per patient-year in this series is similar to that recorded by Szekely (1964) but higher than that of Ellis et al (1959), Ellis and Harken (1961), and of Greenwood et al (1963). The variation in follow-up of the various series is also tabulated, as we have already commented on the increasing incidence in the later post-operative years.…”

“…It is of interest to remember that in the series of Greenwood et al (1963) there was a higher proportion of young patients who might be expected to be in the earlier years of rheumatic history. This, however, does not apply to the cases studied by Ellis et al (1959). As it has been shown that previous techniques employed for assessing pre-operative embolic incidence are likely to be inaccurate, it follows that a comparison with the post-operative incidence cannot be made.…”

“…Previous authors (Ellis et al, 1959;Bannister, 1960;Kellogg et al, 1961 ;Greenwood et al, 1963 ;Szekely, 1964), in discussing the effect of mitral valvotomy on the incidence of systemic embolism, have found difficulty in determining the pre-operative incidence. In any retrospective study it has proved impossible to define the point at which vulnerability to systemic embolism begins in the course of the natural history of chronic rheumatic heart disease.…”

“…Belcher and Somerville (1955) stated, 'a successful valvotomy will not prevent further systemic embolism, but there is reason to believe it will reduce its incidence'. This belief was generally held for some years (Ellis, Connolly, Kirklin, and Parker, 1958;Likoff and Uricchio, 1958;Ellis et al, 1959;Baker and Hancock, 1960). Bannister (1960) followed up a group of patients with mitral stenosis in whom operation was deferred because of slight or trivial symptoms and concluded that, in view of the high incidence of embolism, valvotomy should be performed before the development of progressive LPresent address: The Hospital for Sick Children, Great Ormond Street, London W.C.1 2Hospital for Sick Children, 555 University Avenue, Toronto 2, Canada dyspnoea in all but young patients still in sinus rhythm.…”

“…Surgery has also been recommended as an urgent procedure in patients with recent systemic embolism to prevent further embolic episodes (Ellis, Abelmann, and Harken, 1957;Glenn and McNeill, 1957). These arguments are acceptable only if it is shown that valvotomy reduces embolic incidence.…”