Systematic transesophageal echocardiographic examination in mitral valve repair: the evolution of a discipline into the twenty-first century.

M itral valve repair was first suggested in 1902 by Sir Thomas Brunton (1) as a surgical approach to patients with rheumatic mitral valve disease. However, it was not until after the introduction of the heart-lung machine in 1953 by Gibbons (2) that techniques for the repair of pure mitral valve regurgitation were first introduced by Lillehei et al. (3) in 1957. Because of the development of prosthetic valves, however, further investigation into these techniques was not continued until the limitations of mechanical and bioprosthetic valves became apparent and mitral valve repair became a more viable alternative. In the 1970s, the field was revolutionized when Carpentier et al. (4) presented data detailing the anatomic changes in patients with mitral insufficiency and introduced a physiologic classification of the causes of mitral insufficiency. This provided the foundation of our current understanding of the echocardiographic patterns and anatomic mechanisms of mitral valve regurgitation. Both Carpentier et al. (4), in France, and Duran et al. (5), in Spain, developed mitral valve repair techniques primarily for the management of patients with rheumatic mitral disease. These procedures were attractive to surgeons in the United States who foresaw potential benefits for an older patient population with mitral regurgitation as a result of myxomatous degeneration and ischemia (6,7). From the beginning of the 20th century to the turn of the 21st century, mitral valve repair procedures have developed from a surgical suggestion to a therapeutic intervention used in .2000 patients annually in the United States (8). Valve repair for the management of mitral regurgitation offers the advantages of less perioperative morbidity and mortality, preservation of the mitral tensor apparatus with better maintenance of ventricular function, freedom from anticoagulation, long-term durability, and freedom from reoperation (9). However, the surgical valve repair technique is more technically demanding for the surgeon. The development of improved myocardial protection during cardiopulmonary bypass and the technological advancements of intraoperative echocardiography have enhanced the development of innovative surgical techniques for reparative surgery. Both transesophageal and epicardial echocardiography provide an intraoperative safety net that helps to optimize surgical results with transference of real-time information to the surgical team regarding the underlying valve structure, physiologic abnormality, mechanism, and pathologic process. Intraoperative echocardiography has the added advantage of shortening the learning curve for those surgeons who are incorporating the valve repair techniques into their practice, which translates to benefits for patients. The article by Lambert et al. (10) serves as a reminder of the importance of a comprehensive and systematic transesophageal echocardiographic (TEE) evaluation of the mitral valve apparatus in patients undergoing reparative procedures for mitral regurgitation. Their evaluation included a multiplane segment by segment characterization of leaflet structure and mobility, anatomy of the commissure and subvalvular apparatus, annular and ventricular size, and severity and direction of the regurgitant jet. Successful valve repair requires an understanding of the etiology and mechanism of valve regurgitation. This knowledge is a major determinant of the probability of successful repair, which may vary from 98% in patients with a flail middle scallop of the posterior leaflet to 20% in patients with severe rheumatic valvular disease and restricted bileaflet motion. In their prospective study, Lambert et al. (10) report a small population of 13 patients who underwent surgery for significant mitral regurgitation. The mechanism of regurgitation and location of pathology was identified by using this systematic echocardiographic examination in 12 patients (92%) compared with a Accepted for publication February 26, 1999. Address correspondence and reprint requests to Robert M. Savage, MD, FACC, Department of Anesthesiology, The Cleveland Clinic Foundation, 9500 Euclid Ave., Cleveland, OH 44195.