Assessment of mitral valve function at operation and the prevention of systemic embolism

When assessing the function of the mitral valve at operation by palpation or inspection, the surest way to prevent systemic (cerebral) embolism is to have the ascending aorta occluded by a clamp.

A technique is described which allows safe assessment of mitral valve function by aortic root and left ventricular perfusion, giving a beating-heart preparation with the aorta cross-clamped.

This method has been in successful use for more than two years and has been found particularly useful in the accurate repair of cleft mitral valves in atrioventricular defects (ostium primum defects and atrioventricular canal).

     

Different ways to repair the mitral valve with artificial chordae: a systematic review

Myxomatous mitral regurgitation (type II Carpentier's functional classification) affects about 1-2% of the population. This represents a very common indication for valve surgery resulting in a low percentage of repairs compared to replacement which is actually performed. In the last decades, several methods for mitral valve repair have been developed, to make the surgical feasibility easier, improve the long-term follow-up thus avoiding the need for reoperations. A very interesting method is represented by the combination of various valve repair techniques, depending on the involvement of the anterior, posterior, or both leaflets, and the use of PTFE artificial chordae tendineae when excessive chordal elongation or rupture due to myxomatous degeneration co-exists. The aim of this review is to summarize the evolution of these techniques from the beginning till now.     

Surgical correction of mitral valve stenosis and its recurrence

The article analyses the results of surgical treatment of 1,394 patients with mitral stenosis who were operated on in the period between January 1, 1986 and April 1, 1989. Hospital mortality was 2.0%. Distinct indications for transventricular commissurotomy and mitral valve prosthetics were determined. The choice of the method for mitral stenosis correction was based on the character of the morphological changes in the cusps and subcuspal structures, which were determined during echocardiographic examination. With proper indications transventricular commissurotomy presents a small risk. Hospital mortality was 0.8% in mitral stenosis (among 1,039 patients who underwent operation 8 died) and 2.5% in recurrent stenosis (among 197 patients 5 died). Lethal outcomes were not encountered in stage 11, the mortality rate was 0.6% in stage III and 2.2% in stage IV. Mitral valve prosthetics was performed in 158 patients with 15 (9.5%) lethal outcomes. Hospital mortality was 4.5% in stage III and 10.3% in stage IV of the disease. In the group of patients with mitral stenosis hospital mortality was 7.5% (93 patients underwent operation). Hospital mortality after operations for recurrent mitral stenosis (65) was 12.3%. The initial severity of the patients' condition is still the main factor which influences unfavorably of the immediate results of mitral valve prosthetics.     

Testing of mitral valve competence following combined mitral valve repair and aortic valve replacement

A simple, effective technique for testing the results of repair and reconstructive procedures on the mitral valve apparatus is described. This technique can be used in the operative setting of combined aortic valve replacement and mitral valve repair where other reported techniques for testing the valve apparatus are rendered unfeasible.     

Papillary fibroelastoma of the mitral valve associated with rheumatic mitral valve stenosis

With the advent of echocardiography, diagnosis of papillary fibroelastoma in living patients has been made possible, yet papillary fibroelastoma found in the living remains a very rare cardiac tumor. We report a case of papillary fibroelastoma of the mitral valve with rheumatic mitral valve stenosis. A 68-year-old woman was referred to our hospital with a mitral valve tumor and rheumatic mitral valve stenosis. She underwent anticoagulation therapy with Warfarin for 8 years since having a cerebral embolization. Echocardiography revealed a mass attached to the mitral valve, with severe mitral valve stenosis. Electrocardiography demonstrated a chronic atrial fibrillation. Tumor excision with mitral valve replacement and maze procedure were performed. Both the surgical and histological findings depicted papillary fibroelastoma. The postoperative course was uneventful and the patient has remained symptom-free one year after surgery.     

Reconstruction of the mitral valve

Isolated mitral valve reconstruction was performed in 100 consecutive patients for either mitral regurgitation or combined mitral valve disease. Early mortality was 8% for the total series but has decreased to 2% since 1965. Eight late deaths occurred between 2 and 99 months after operation.Preoperatively all but 2 patients were in Functional Class III or IV according to the New York Heart Association classification. One to two years after operation 72 patients were ameliorated by one to three functional classes and 7 were unchanged. Four to nine years postoperatively 28 were still improved by one to three functional classes while 3 were the same as preoperatively, and 5 patients had died during this late follow-up period.Objective assessment of postoperative mitral valve function by apnea curves and dye-dilution curves yielded good long-term results. Postoperative cardiac catheterization studies demonstrated a marked decrease in pulmonary artery and pulmonary capillary wedge pressures. Six patients had to be reoperated upon because of either progressing rheumatic disease or unsatisfactory repair. Analysis of actuarial survival curves demonstrates more favorable results with mitral valve reconstruction than with mitral valve replacement in comparable series, primarily because of the low embolus rate after reconstruction.