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Mitral valve repair (MVR) is the treatment of choice in cases of degenerative mitral valve (MV) regurgitation, with superior results compared to MV replacement. The feasibility of the procedure is up to 95% and it should be considered in all patients. Different techniques have been described, comprising procedures on valve leaflets, the subvalvular apparatus, and annulus. Posterior leaflet prolapse is traditionally corrected by Carpentier’s quadrangular resection with or without sliding plasty. Anterior leaflet prolapse is still more technically demanding and various types of reconstructive techniques have been described, not always leading to satisfactory overall results. Efforts to find a substitute for elongated or ruptured chordae date back to the 1960s.

In October 1955, I started training in General Surgery at the Mayo Clinic (Rochester, MN). On the third Saturday afternoon in October, I observed John Kirklin performing an open heart operation using extracorporeal circulation. On Monday, I visited the Fellowship Office and requested the addition of Thoracic Training to my studies. This was added and carried with it the requirement of writing a thesis. For this task, my advisor Dr. Bunky Ellis gave me a project: development of a mitral valve prosthesis. This was a virgin field at the time and I first asked myself the question: how does the mitral valve work? In 1959, I started my thesis in the classical manner by studying the anatomy of any mitral valve I could get my hands on. I dissected the hearts of humans, dogs, deer, guinea pigs, beaver, etc. My major conclusion from this effort was that mitral valve anatomy was dominated by irregularity.

Ebstein’s anomaly is an unusual congenital heart lesion notable for its extremely variable anatomy. One characteristic is the differing degree of dysplasia and displacement of the proximal attachments of the septal and posterior leaflets from the true atrioventricular junction. The anterior leaflet is normally attached to the tricuspid annulus but is usually larger than normal, with a sail-like aspect and various degrees of interchordal space obliteration and adherence to the ventricular wall. In Ebstein’s anomaly, the valve divides the right ventricle into a proximal part between the atrioventricular junction and the displaced valve, called the atrialized portion of the right ventricle, and a distal part, called the functional right ventricle. Between 10% and 15% of these patients have accessory conduction pathways, while Wolff–Parkinson–White syndrome is the most frequent. An atrial septal defect is present in most of the patients and may result in a right-to-left shunt with cyanosis.

Ebstein’s anomaly is the 18th most common congenital heart defect (1% of all congenital heart defects). It occurs in 0.3–0.8% of all congenital heart diseases in the first year of life, 1: 20000–50000 live births. There is equal male to female occurrence.

Heart transplantation programs have increased the availability of valve allografts, resulting in a resurgence in their use to replace or repair severely diseased valves. Mitral valve allograft was first transplanted in the dog by Robicsek and colleagues (14) in 1962. Two years later, the mitral allograft was experimentally implanted in the mitral position by Cachera et al. (4). However, experimental results with mitral allografts to substitute mitral valves were not satisfactory, as Rastelli et al. (10) demonstrated at the Mayo Clinic. By that time, Hubka et al. (6) trying to replace the atrioventricular valves with mitral allografts obtained unpredictable results. Methods of sterilization and preservation were the main limitations to the use of mitral allografts with this technically demanding operation for valve replacement. Advances on the methods of harvesting, sterilization, preservation and storage of heart valves, for more than three decades, were determinants for the satisfactory clinical results with aortic allografts. Cryopreservation of valve allografts was introduced by O’Brien in Australia, 20 years ago (8, 9), and later with minor modification by Kirklin (7) at the University of Alabama; since then, institutions worldwide have organized heart tissue banks. Most of them have preserved aortic and pulmonary valves, and only a few have experience with mitral allografts.