Surgical Treatment for Heart Failure

ICM is defined as diffuse akinesis of the ventricle after myocardial ischemia, and the pathology is different from LV aneurysm, which is dyskinesis after myocardial infarction. The etiology has been described as chronic LV remodeling after the ischemia,1 and the surgical treatment of ICM was thought to be heart transplantation only. However, the new surgical procedure of endoventricular circular patch plasty (EVCPP) showed to be an alternative treatment for ICM.2,3 The EVCPP4,5 is performed with cardioplegic heart arrest. After complete coronary revascularization, the LV is opened in the center of the anterior lesion. Clots, if present, are removed. In akinetic segments, the junction between scarred and normal muscle is not as clearly defined as in dyskinetic aneurysms, though the endocardial scar determines the border zone between totally fibrous tissue and the beginning of muscular tissue. With ventricular arrhythmia, the endocardial scar is mobilized and resected, and cryotherapy is applied to the edge of the resection. A 2-0 Prolene endoventricular circular suture, as described by Fontan, is placed to restore the “neck” of the contracting ventricle and thereby provide a more normal oval curvature of the chamber. The circular suture is passed in the fibrous tissue above the transitional zone between normal and scarred tissue to construct the “artificial neck” that will be closed with a Dacron patch. The area excluded includes almost half of the septum and the posterior wall up to the root of the posterior papillary muscle. After closure, the excluded external tissue is folded to reinforce the suture line. With this procedure, the LV is restored at the anteroseptal site with small patch. The volume and the size of the LV decreases; however, the spherical shape of the LV does not become elliptical. The conical pattern of normal cardiac size and shape is well known. The spatial arrangements of this structural pattern is closely linked to the helical ventricular myocardial band, a myocardial fold that separates the surrounding wrap of the basal loop from the oblique fibers that form the apical loop, composed of descending and ascending segments with a spiral vortex at the apex. Based on this structural morphology, the normal motion of the heart brings suction and ejection with apical torsion and an elliptical shape. 6–11 Size and shape changes follow dilated cardiomyopathy (DCM) as the enlarged ventricle develops a spherical configuration. A postulated geometric component is spherical widening of the apical loop, whereby the architecture of the oblique apical loop fibers becomes more transverse to more closely resemble the horizontal fiber orientation of the basal loop. In end-stage DCM, the shape becomes spherical with no torsion of the LV apex. The septal anterior ventricular exclusion (SAVE or Pacopexy) technique was developed to exclude large anteroseptal akinesis and restore the shape of the LV,12,13 as shown in Figure. 14 Following initiation of cardiopulmonary bypass and blood cardioplegic heart arrest, complete coronary revascularization is performed, and mitral repair for mitral regurgitation (MR) via left atriotomy or tricuspid surgery via right atriotomy, is performed as necessary. The aortic cross-clamp is then released to allow the heart to start beating, as the SAVE operation is usually performed on the beating heart, and perfusion pressure is kept above 75 mmHg to ensure ongoing coronary perfusion. In a study of cardioplegia in the failing heart, 15 it was found that during the operation, cardioplegic delivery for protection is “time dependent” (ie, needing ischemic intervals), whereas beating nourishment is “procedure dependent” and continuous perfusion is provided throughout the procedure is suggested. The importance of maintaining high perfusion pressure is emphasized. In normal hearts, venting (Received December 3, 2008; revised manuscript received March 5, 2009; accepted March 11, 2009; released online May 28, 2009) Cardiovascular Surgery, Hayama Heart Center, Kanagawa, Japan Mailing address: Tadashi Isomura, MD, Hayama Heart Center, 1898 Shimoyamaguchi, Hayama, Kanagawa 248-0116, Japan. E-mail: [email protected] All rights are reserved to the Japanese Circulation Society. For permissions, please e-mail: [email protected] Surgical Treatment for Heart Failure