Correspondence
Mitral Regurgitation Due to Flail Leaflet
N Engl J Med 1997; 336:1322-1324May 1, 1997
- Article
To the Editor:
Ling et al. (Nov. 7 issue)1 conclude that patients with serious mitral regurgitation due to flail leaflet do better with early surgical management. Their patients in New York Heart Association class I or II had an annual mortality rate of 4.1 percent with medical therapy.
Although in general agreement with the recommendations of Ling et al., Ross in his editorial2 expresses reservations about immediate surgery in asymptomatic or mildly symptomatic patients with normal left ventricular function (ejection fraction, >60 percent). He suggests annual clinical and echocardiographic examination to detect deteriorating left ventricular function.
We have extensive experience in the surgical management of mitral valve disease3,4 and practice early surgery in patients with hemodynamically important degenerative mitral regurgitation.5 There are two additional reasons to support this policy that were not addressed by the Mayo Clinic workers or by Ross. First, a large majority of patients with severe mitral regurgitation due to flail leaflet have “degenerative” leaflets that are consequently partly or entirely voluminous and “floppy.” 6 Potentially fatal ventricular ectopy may occur in such cases and may be produced or aggravated by exercise.6 The associated mitral regurgitation need not be hemodynamically severe.7 Improvement in or disappearance of the multifocal ventricular ectopic beats is frequently achieved after appropriate surgery, which should include decreasing leaflet size and shortening elongated chordae to restore valve competence.5,7 Circumstantial evidence that ventricular arrhythmias are causally related to the floppy mitral valves is provided by long-standing observations 6 that ventricular ectopy is not a feature of rheumatic mitral regurgitation, irrespective of its severity, in which leaflets are not voluminous.4,6 We recommend stress testing and Holter monitoring to check for multifocal ventricular ectopy in all patients with degenerative mitral regurgitation, especially if direct questioning reveals a history of palpitations or syncope; their detection provides a strong indication for surgery.
The second reason for early surgery relates to technical aspects of the mitral-valve repair itself. When the anterior mitral leaflet is involved, as it was in nearly 20 percent of the patients studied by Ling et al., the stretched or ruptured chordae to that leaflet must be corrected. This becomes more complex with increasing severity of the disease, and the insertion of Gortex chordae may even be necessary. Although correction of degenerative mitral regurgitation should be feasible in all instances,5 advanced involvement of the anterior leaflet inevitably predisposes patients to a longer surgical procedure or even valve replacement.
7 ReferencesJohn B. Barlow, M.D.
Robin H. Kinsley, M.B., B.Ch.
University of the Witwatersrand, Johannesburg 2193, South Africa1
Ling LH ,Enriquez-Sarano M ,Seward JB , et al. Clinical outcome of mitral regurgitation due to flail leaflet. N Engl J Med 1996;335:1417-1423
Full Text | Web of Science | Medline2
Ross J Jr . The timing of surgery for severe mitral regurgitation. N Engl J Med 1996;335:1456-1458
Full Text | Web of Science | Medline3
Antunes MJ ,Magalhaes MP ,Colsen PR ,Kinsley RH . Valvuloplasty for rheumatic mitral valve disease: a surgical challenge. J Thorac Cardiovasc Surg 1987;94:44-56
Web of Science | Medline4
Marcus RH ,Sareli P ,Pocock WA ,Barlow JB . The spectrum of severe rheumatic mitral valve disease in a developing country: correlations among clinical presentation, surgical pathologic findings, and hemodynamic sequelae. Ann Intern Med 1994;120:177-183
Web of Science | Medline5
Barlow JB . Mitral valve disease: a cardiologic-surgical interaction. Isr J Med Sci 1996;32:831-842
Medline6
Barlow JB . Idiopathic (degenerative) and rheumatic mitral valve prolapse: historical aspects and an overview. J Heart Valve Dis 1992;1:163-174
Medline7
Pocock WA ,Barlow JB ,Marcus RH ,Barlow CW . Mitral valvuloplasty for life-threatening ventricular arrhythmias in mitral valve prolapse. Am Heart J 1991;121:199-202
CrossRef | Web of Science | Medline
To the Editor:
Although the findings of Ling et al. add credibility to the policy of early operation already adopted by some experienced thoracic surgeons, the editorial by Ross recommends surgery for severe mitral regurgitation only in patients with compromised left ventricular ejection fractions or symptoms of heart failure. However, we do not know how many patients will benefit — or suffer — from postponing mitral valve repair until symptoms of left ventricular dysfunction occur. Other authors have developed guidelines for the timing of surgery that are based on additional factors such as left ventricular systolic diameter, pulmonary systolic pressure, and the presence of atrial arrhythmias.1 The indication for mitral valve repair in asymptomatic patients has also been based on the severity of mitral regurgitation and its associated valvular pathology rather than on functional criteria.2
Large-scale studies on the role of medical and surgical management of severe mitral regurgitation are lacking and are unlikely to become available in the near future. Nonetheless, we now know that this condition is neither rare nor benign. The role of expectant management is therefore problematic with regard not only to the medical facts but also to the ethics of counseling patients. Rather than pacifying patients with severe mitral regurgitation with nonspecific optimism, physicians need to inform them about the specific, substantial, and frequently fatal risks associated with their disorder. Only knowing about these risks and about the excellent results of timely mitral valve repair will enable patients to make treatment decisions they will not come to regret.
2 ReferencesSebastian R. Fetscher, M.D.
Freiburg University Medical Center, Freiburg 79106, Germany1
Stewart WJ. Choosing the “golden moment” for operation in the era of valve repair for mitral regurgitation. Learning Center Highlights. Summer 1995:2-7.
2
Carpentier AF ,Lessana A ,Relland JY , et al. The “physio-ring“: an advanced concept in mitral valve annuloplasty. Ann Thorac Surg 1995;60:1177-1186
CrossRef | Web of Science | Medline
Author/Editor Response
The authors reply:
To the Editor: My colleagues and I appreciate the interest of Drs. Barlow and Kinsley in our study of mitral regurgitation due to flail leaflet. The decision about whether or not to proceed with surgery for multifocal ventricular ectopy is important because of the notable incidence of sudden death in patients with mitral regurgitation due to flail leaflets.1 However, the predictors of sudden death in patients with mitral prolapse have not been firmly established,2-4 and there is no clear evidence at this point that valve surgery eliminates the arrhythmia5 or the risk of sudden death. Therefore, we do not now recommend mitral surgery for arrhythmia detected by stress testing or Holter monitoring, but we agree with Barlow and Kinsley that further studies are needed. Taking into account the minimal risk of surgery, we currently consider mitral surgery in patients less than 75 years old with ejection fractions of 60 percent or more, irrespective of symptoms or arrhythmias, if mitral regurgitation is severe and the valve appears repairable. The rationale of this approach is that complications of severe volume overload may be prevented by eliminating the volume overload.6
However, we are more conservative in recommending surgery for mitral regurgitation that does not meet the criteria for severe regurgitation as determined by quantitative Doppler echocardiographic methods. We agree with Barlow and Kinsley that the new surgical procedures (transposition of chords or artificial chord insertion) have considerably expanded the field of application of valve repair, in particular for patients with anterior-leaflet flails. The knowledge that flail or prolapsed anterior leaflets are now as repairable as flail posterior leaflets has markedly simplified and expanded the indications for surgery.
Fetscher discusses the important point of describing to patients the risks and potential benefits of the conservative and surgical approaches. Currently, once the diagnosis of severe mitral regurgitation has been established, in particular using quantitative methods, we consider and discuss early surgery with the patient. The conservative approach of medically monitoring patients with severe mitral regurgitation is difficult because all the suggested prognostic indexes have a wide range of uncertainty and have not prevented the occurrence of “unexpected” left ventricular dysfunction. The early surgical approach is possible because of the high feasibility and low risk of valve repair in the hands of experienced surgeons. Its rationale is supported by the risk incurred by the patients treated medically 1 and by the improvement in outcome provided by early surgery.6
6 ReferencesMaurice Enriquez-Sarano, M.D.
Mayo Clinic, Rochester, MN 559051
Ling LH ,Enriquez-Sarano M ,Seward JB , et al. Clinical outcome of mitral regurgitation due to flail leaflet. N Engl J Med 1996;335:1417-1423
Full Text | Web of Science | Medline2
Stein KM ,Borer JS ,Hochreiter C , et al. Prognostic value and physiological correlates of heart rate variability in chronic severe mitral regurgitation. Circulation 1993;88:127-135
Web of Science | Medline3
Stoddard MF ,Prince CR ,Dillon S ,Longaker RA ,Morris GT ,Liddell NE . Exercise-induced mitral regurgitation is a predictor of morbid events in subjects with mitral valve prolapse. J Am Coll Cardiol 1995;25:693-699
CrossRef | Web of Science | Medline4
Farb A ,Tang AL ,Atkinson JB ,McCarthy WF ,Virmani R . Comparison of cardiac findings in patients with mitral valve prolapse who die suddenly to those who have congestive heart failure from mitral regurgitation and to those with fatal noncardiac conditions. Am J Cardiol 1992;70:234-239
CrossRef | Web of Science | Medline5
Vohra J ,Sathe S ,Warren R ,Tatoulis J ,Hunt D . Malignant ventricular arrhythmias in patients with mitral valve prolapse and mild mitral regurgitation. Pacing Clin Electrophysiol 1993;16:387-393
CrossRef | Web of Science | Medline6
Ling LH, Enriquez-Sarano M, Seward JB, et al. Early surgery in patients with mitral regurgitation due to flail leaflets: a long-term study. Circulation (in press).
Author/Editor Response
In their letter concerning my editorial, Barlow and Kinsley indicate that their extensive experience with surgical repair of the “floppy” mitral valve supports early surgical intervention as recommended by Ling et al., and they propose two additional indications: potentially fatal ventricular ectopy (detected by stress testing and Holter monitoring) and involvement of the anterior mitral-valve leaflet (which occurs in approximately 20 percent of patients). These additional indications in subgroups of patients should certainly be considered, but for the majority of patients who do not have these indications and who have severe mitral regurgitation due to degenerative disease, few symptoms, and clearly normal left ventricular function, data to compare immediate surgical repair with careful medical follow-up are not available. Therefore, until such information on early and late mortality is obtained in a prospective manner, close clinical and echocardiographic follow-up of asymptomatic or minimally symptomatic patients having initially normal left ventricular ejection fractions, with surgical intervention being undertaken when the ejection fractions reach the lower limit of normal (55 to 60 percent),1 remains a reasonable alternative to immediate operation.
1 ReferencesJohn Ross, Jr., M.D.
University of California, San Diego, School of Medicine, La Jolla, CA 920931
Ross J Jr . The timing of surgery for severe mitral regurgitation. N Engl J Med 1996;335:1456-1458
Full Text | Web of Science | Medline
