OBSTRUCTIVE HYPERTROPHIC CARDIOMYOPATHY
Myectomy has been performed for over 50 years to resolve the obstruction in obstructive hypertrophic cardiomyopathy.
Myectomy for abolish LV outflow obstruction. It consists in removing a portion of about 2-3 cm of the hypertrophic septum (Extended myectomy) and in repairing the mitral valve (mitral plastic surgery), in order to avoid the regurgitation of blood in the left atrium during the contraction and emptying of the LV, whose outflow tract is blocked. Adhesions between the ventricular walls and the mitral valve apparatus are also removed and the size of the papillary muscles, if hypertrophic, is reduced.
In highly experienced centres in the intervention of myectomy, the obstruction is abolished in almost all patients. With resection of the muscle and plastic of the valve it is avoided to replace the mitral valve with a prosthesis and this approach is usually associated with substantially better results. However, when the state of the mitral valve is very compromised, it is however necessary the replacement of the mitral valve with a mechanical or biological prosthesis.
The intervention of Myectomy and mitral valve surgery requires one specific experience on the part of the surgeon e there are few centers in Europe with great experience. The remote results are favorable with abolition of obstruction, substantial improvement of symptoms in almost all patients, reduction of hypertrophy of all ventricular walls.
Il operative risk it's short (less than 1% generally in centers with great experience), but varies according to the patient's condition (age, associated pulmonary or coronary or renal disease, etc.) and the additional problems present (for example, the need to perform an aortocoronary bypass, to replace the valve aortic, etc).
It has recently been shown that the shorter the time between documentation of the outflow obstruction and its resolution, the better the remote results. In other words, the best results are obtained if the obstruction has not been present for many years, resulting in atrial dilation and increased pulmonary pressures.
Myectomy for abolish midventricular obstruction. It consists in removing part of the hypertrophic muscle at a deeper level together with fibromuscular branches responsible for the obstruction, identified by means of a High precision cardiac magnetic resonance, performed in Centers of Excellence. It is often associated with a ventricular aneurysm, within which a thrombus can also form. In this case the apical aneurysm must be opened and removed as well as the thrombus, and the muscle or the fibromuscular branches in excess, responsible for the obstruction. Monza, Careggi-Florence Hospital)
The recent ones international guidelines on HCM, recommend surgery of myectomy as the therapy of first choice in patients with obstructive HCM and symptoms that do not respond to drug therapy
Cardiac surgery in Dilated cardiomyopathy more frequent consists of mitral plastic or mitral valve replacement with biological or mechanical prosthesis, or aortic prosthesis, in relation to the age of the patient.
RESTRICTIVE CARDIOMYOPATHY (MYOCARDIC ENDOFIBROSIS)
In cases, rare in the West, more frequent in African populations, of Endomyocardial fibrosis, cardiac surgery to extract the thickening of the heart cavities can give good results even if its complexity limits the results.
In patients with cardiomyopathy and severe reduction of cardiac contractility is indicated heart transplant, that is, the replacement of the diseased heart with a new compatible heart. Cardiac surgery has a relative complexity, while the management of its complications, linked in particular to immunosuppression that must be implemented in order to accept the "new" heart, is usually responsible for the failures in the first month. Subsequently, periodic checks, including myocardial biopsies, must be performed to evaluate and manage any "rejection" crises. After one year the recovery is generally excellent with the restoration of a normal capacity for effort and work