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Until recently refractory congestive heart failure under optimal medical treatment could only be treated surgically by heart transplantation. Many factors, such as a lack of donors, an operative mortality rate of 10–20%, and side effects associated with immunosuppression, have prompted heart surgeons to find alternative treatments. Moreover the number of heart failure patients is steadily growing. Although medical treatment has changed the course of the disease, it has only helped to slow the process of deterioration. Patients referred for surgery show a longer evolution than in the past and are probably more sick. Since the early '90s many surgical options have appeared and, like medical treatment, should allow a tailored surgical approach. Ischaemic cardiomyopathies can benefit from myocardial revascularisation even in patients without angina and an ejection fraction below 20%.1 2 Such patients could already have some kind of ventricular reduction with use of the Dor procedure in dyskinetic and akinetic areas.3 More recently, Bolling has called our attention to the deleterious effect of mitral regurgitation in such failing ventricles and advocated a simple annuloplasty to make the mitral valve competent again.4 All these options can be used either in isolation or in combination in any given patient. On the other hand, dilated cardiomyopathy has lacked alternative solutions to heart transplantation. Recently, two surgical options became available at the same time: isolated mitral valve repair, and left ventricular reduction with correction of mitral regurgitation—the Batista procedure.
Mitral valve repair was pioneered by Bolling and represents probably the easiest and most elegant way to treat a key factor of congestive heart failure.4 In a series of more than 60 patients evenly distributed among ischaemic and dilated cardiomyopathies, Bolling's operative mortality is extremely low (< 2%). Actuarial survival reaches 82% at one year and 72% at two years. More interestingly, all patients have improved not only functionally but also haemodynamically. However, it seems doubtful whether all patients—irrespective of their aetiology, size of left ventricular cavity, or presence of severe pulmonary hypertension—can benefit from a simple mitral valve repair. It always seems difficult to admit that a procedure has no contraindications and that its promoter did not find any algorithm to make the decision whether or not to correct mitral regurgitation in end stage congestive heart failure patients. No other series has shown similar data. Although results from other authors would show restrictive indications, higher operative mortality and less improvement, the question remains: should this surgical option be thrown away? Probably not, because we are only searching for a palliative procedure which can significantly improve survival and—moderately, if not mildly—functional and haemodynamic status.
The other surgical option—the Batista procedure—has been associated with many mistakes, mainly because of its revolutionary concept and its incredible media impact; both never do well in the medical field. Batista has proposed this operation in a huge country where heart transplantation is not available and therefore no selection criteria was described, no pre- and postoperative data were recorded, and midterm survival could not be accurately reported. Many surgical centres around the world, mainly in the USA, have applied Batista's principles without any critical analysis before its clinical application.
Is patient selection the key?
Not surprisingly, results were very poor and this option was recommended to be abandoned. However, very few have tried to select patients such as was done at the Cleveland Clinic Foundation, where McCarthy and colleagues have separated ischaemic cardiomyopathies from dilated idiopathic cardiomyopathies.5 Considering that a scarry, patchy myocardium could not offer a predictable response to the Batista operation, they have recommended to use it only in idiopathic cardiomyopathies. This tremendous improvement in patient selection has led to improved results. Experience of operating on 57 patients has shown that mechanical support may be necessary to decrease operative mortality as 11 patients (17%) required a left ventricular assist device (LVAD) postoperatively. However, not all countries can afford such a policy for economical reasons. Actuarial survival is 82% at one year and data are not available beyond that period. Young age seems to be a risk factor and this procedure should probably be offered to patients who cannot receive heart transplantation, either for age reasons or for risk factors associated with heart transplantation. Finally, actuarial freedom from failure was close to 60% at one year. This last point is probably the most crucial because it shows that in this series, left ventricular reduction to a certain extent has unpredictable results. Do these results mean that this operation is not effective and unreliable, or does it mean that selection of candidates is still not restrictive enough? Many other factors concerning the adequate amount of myocardium to be removed, and the need for mitral regurgitation correction (either with mitral repair or with mitral valve replacement), still need to be further analysed and explained. Likewise the whole concept relies on systolic dysfunction, and no one has ever addressed the question of diastolic dysfunction, which can become important when the size of the cavity becomes smaller.
Timing of the procedure
Many factors concerning indications, timing, and surgical approach need to be clarified. For example, what is the most appropriate timing for such a procedure? Should patients be operated upon when stabilised in New York Heart Association (NYHA) functional class III, or should it be performed when patients are in class IV and sometimes inotrope dependent? In our small series, one patient had been assessed and found to be an excellent candidate. This patient remained stable in NYHA class III for three years. He progressively deteriorated and when he became class IV, specific echocardiographic parameters favouring the Batista procedure disappeared. His ongoing deterioration prompted us to insert an LVAD as a bridge to transplantation. We strongly believe that fibrosis may be related to the duration of the disease.
Considering the size and the shape of ventricular reduction, the Laplace law has been applied to this concept. However, it can only be an approximation which does not allow to us to predict scientifically whether removing a width of 3 cm would be better than removing more or less. Moreover there is no scientific means by which to decide what amount of ventricular mass should be left according to a given size of ventricular cavity. From the surgical standpoint it seems easier to remove a wedge shaped piece of myocardium with its base at the apex of the heart. However, the base is always more dilated than the apex and probably a wedge resection with its base at the base of the heart would be more efficient, although more challenging. Concerning the mitral valve treatment, it remains a key point for those who both favour and deny the efficacy of the Batista procedure. For those who dislike the procedure, an isolated mitral valve repair would always be sufficient, irrespective of the size of the left ventricle, such as in Bolling's theory. For those who favour the Batista operation, we believe that mitral regurgitation correction is only one component of the operation, but is not enough by itself.
We, like McCarthy, have performed the Batista operation in patients with a very dilated left ventricle (end diastolic dimensions ⩾ 90 mm) without concomitant mitral regurgitation, which proved to be successful. This shows that the mitral component in some patients is not the main factor for heart failure. Like others, we believe that papillary muscles, as well as the mitral annulus, are the main components of the left ventricle and play a role, not only in systolic but also in diastolic dysfunction. As opposed to Batista's recommendation which states, “the more myocardium removed, the better”, we think that mitral valve repair is probably the only option to treat mitral regurgitation in such patients. Batista's recommendations for resecting more myocardium with the mitral valve apparatus can be detrimental and might explain the poor results reported after such a procedure. Do these results, which do not meet the expectations but still achieve more than 80% survival at one year, mean that this operation should be abandoned, or does it mean that selection was not adequate? This procedure is not favoured anymore, especially in the USA, because its results were not predictable. Is it because the concept is not valid, or is it because more powerful predictive factors have not been described until now?
In our personal series, we have assessed 52 patients showing idiopathic dilated cardiomyopathies exclusively. Patients, as a first step, met the Cleveland Clinic criteria such as an end diastolic diameter > 70 mm, a wall thickness > 0.7 cm, and a distance between both papillary muscles > 3 cm. As a second step all patients underwent stress dobutamine echocardiography at low doses (< 12 μg/kg/min). Many parameters were recorded before and after dobutamine infusion—mainly stroke volume, wall thickness, mitral regurgitation evolution, and pulmonary pressure. All parameters were searching for a contractile reserve. The most powerful predictive parameter for good outcome seems to be an increase of more than 30% of the stroke volume provided that pulmonary pressure does not show a steep augmentation. Only eight patients met our criteria and underwent a left ventricular reduction associated with a mitral valve repair. In all instances a prosthetic ring was sutured and an Alfieri stitch used to increase coaptation. It also has to be stressed that in seven cases a tricuspid repair has been performed by using a tricuspid ring. We strongly believe that such correction can decrease right ventricular afterload, just as mitral regurgitation correction decreases left ventricular afterload. Six patients are long term survivors with follow ups of 1–3 years. All have improved significantly—both functionally and haemodynamically— and their left ventricular cavity has not redilated. Of the two deaths, one was caused by septic shock in the early postoperative phase, and the other resulted from chronic renal failure. All patients who underwent this procedure were in NYHA class IV, and four out of eight were inotrope dependent. All patients had a peak oxygen consumption < 14 ml/min/m2.
Although our experience is very small, we believe that there is a place for the Batista operation in patients with severe congestive heart failure and who, for some reason, cannot undergo heart transplantation. We also believe that no more than 20% of idiopathic cardiomyopathies are appropriate for this procedure, and that further investigations are required to define a suitable candidate in this regard. According to our histological data, patients who underwent the Batista operation showed mild myocardial fibrosis or none at all. On the other hand, those patients who underwent heart transplantation, after a Batista assessment, showed in all cases diffuse and moderate or severe fibrosis in the myocardium. Is fibrosis the key answer?
The future for the Batista procedure
Is there any future for this operation? We believe that there is, mainly because of the lack of donors for transplantation and the increasing number of heart failure patients who sooner or later will not respond to optimal medical treatment. Techniques to assist a failing heart in order to allow its potential recovery have recently been proposed. This approach, although uncommon, has been reported by several authors after LVAD implantation and secondary removal, thereby avoiding heart transplantation. Perhaps the future of the Batista procedure will be linked to heterotopic heart transplantation, which will allow a temporary unloading of the repaired ventricle and thus safely differentiate between those patients able to live without a second heart and those who permanently need this assistance.
Heart failure surgery is at its early phase, especially for palliative procedures, and further elaboration and investigations are required before any definitive conclusions can be drawn.