REVIEW Cardiovascular Surgery Circ J 2009; Suppl A: A-1 – A-5 Surgical Treatment of Ischemic Heart Failure The Dor Procedure Marisa Di Donato, MD*,**; Serenella Castelvecchio, MD*; Lorenzo Menicanti, MD* Despite the improvements in the treatment of myocardial infarction that have translated into a decline in mortality rates, the incidence of heart failure has increased and, because of the limited number of cardiac donors, non- transplant heart surgery has developed in the past 10 years. Surgical ventricular reconstruction was launched by Dor and defined as endoventricular circular patch plasty repair. It represents a relatively novel surgical approach aiming to restore (bring back to normal) the dilated, distorted left ventricular (LV) cavity in order to improve function. The term ‘surgical ventricular reconstruction/restoration’ includes operative methods that reduce LV volume and restore its shape. The concept of reducing wall stress through surgical restoration of chamber size and geometry remains the guiding principle behind this innovative technique. Results from different Institutions are uniform and show an improvement in cardiac and clinical status and in survival. The present review will approach the rationale to re-shape the heart on the basis of pathophysiology and cardiac architecture, and will describe the efficacy of the Dor procedure in ischemic dilated cardiomyopathy, as well as some technical aspects and patient selection pathway. (Circ J 2009; Suppl A: A-1 – A-5) Key Words: Ischemic heart failure; Patient selection; Surgical ventricular restoration oronary artery disease in Western countries is respon- or have comorbidities that preclude transplantation; more- sible for more than 75% of heart failure (HF) over, the scarce number of donors makes the treatment C cases.1,2 Despite the improvement in the treatment unavailable for most patients on a waiting list. of myocardial infarction (MI) over the past 4 decades, Given these limitations, non-transplant heart surgery has which has translated into a decline in mortality rates after developed in the past 10 years and the role of cardiac sur- MI, the incidence of HF in recent decades has increased geons in treating HF patients has changed, although cardi- and greater salvage of high-risk MI patients in recent times ologists are still reluctant to send patients for non-transplant may have contributed to this trend.3 The clinical syndrome surgical alternatives and guidelines for CHF do not even of congestive HF (CHF) progresses from no or scarce mention some strategies, such as the Dor procedure. symptoms (compensated) to moderate or severe symptoms (decompensated). Decompensated HF has advanced struc- tural cardiac disease with symptoms at rest (New York The Dor Procedure Heart Association (NYHA) class IV or stage D HF) despite In 1985 Jatene described a new technique of performing optimal medical therapy, and carries an extremely poor a circular endoventricular suture (Fontan stitch) to exclude prognosis. In the Rematch study, only 8% of patients in the the dyskinetic scar of an aneurysm,6 and in the same year medically treated group were alive at 2 years, with signifi- Dor et al described the use of the endoventricular Fontan cant costs and resource consumption.4 Increased chamber suture to rebuild a failing ventricle with an endoventricular sphericity and the presence of mitral regurgitation are patch after extended endocardectomy for ventricular tachy- markers of poor prognosis and are determined by severe cardia.7 Dor was the first surgeon to demonstrate that the abnormalities in chamber geometry that subtend the pro- endoventricular patch plasty repair could be applied not gression of the disease, according to the biomechanical only to left ventricular (LV) aneurysm but also to a dilated model of HF.5 Advanced, stage D HF affects between 300,00 akinetic ischemic LV. He emphasized the concept of reduc- and 800,000 patients in the United States, which generates ing the LV size and reconstructing a more elliptical cavity, an enormous economic burden without obtaining substan- treating the dilatation in all its components (anterior, apical tial symptomatic benefit or improvement in prognosis. For and septal), as opposed to linear resection of the aneurysm endstage HF patients, cardiac transplantation is the treat- that left an untouched septal dilatation, creating a distortion ment of choice, but most patients are over 65 years of age of the residual chamber. The concept of excluding all the diseased tissue from the cavity, especially the septum, is 7 (Received November 20, 2008; revised manuscript received February the basis of the good results. 19, 2009; accepted March 11, 2009; released online May 27, 2009) The Dor technique is a relatively novel surgical approach *Department of Cardiac Surgery, IRCCS San Donato Hospital, Milan, to restoring (bringing back to normal) the dilated, distorted **Department of Critical Care Medicine, University of Florence, LV cavity in order to improve function. It implies knowl- Florence, Italy edge and understanding of the remodeling infrastructure, Mailing address: Marisa Di Donato, MD, Department of Cardiac Surgery, IRCCS, San Donato Hospital, Via Morandi 30, 20097 San the structural changes leading to geometry abnormalities, Donato, Milanese (Milan), Italy. E-mail: [email protected] the role of compensatory, remote muscle and of stretching All rights are reserved to the Japanese Circulation Society. For permis- mechanisms that lead to electrical disadvantage.8 sions, please e-mail: [email protected] The procedure includes coronary grafting and mitral Circulation Journal Supplement A 2009 A-2 DONATO MD et al. Figure 1. (Left) Use of internal sizing and shaping device and the position of the patch are shown. Notice that the patch is obliquely oriented towards the aortic tract, parallel to the septum. (Right) Mammary artery graft is in place and the venous sequential distal anasto- mosis already performed. The opening of the ventricle is shown at the end of the procedure. Notice the everting suture to close the opening with the patch that is tailored during the closure. repair when needed, so it has the potential to treat the 3 for posterolateral dilatation caused by inferior/lateral MI components of HF: the ventricle, the vessels and the valve with the occlusion of the circumflex or right coronary artery. (“triple V” as defined by Buckberg).9 The term surgical ven- In our experience, nearly 98% of patients need concomitant tricular reconstruction/restoration (SVR) includes operative coronary artery bypass grafting (CABG), and many also methods to reduce LV volume and restore the ventricular undergo mitral valve repair (20–25% of cases). elliptical shape. The concept of reducing wall stress through surgical restoration of the LV chamber size and geometry remains the guiding principle behind this innovative tech- Surgical Details of Anterior SVR nique. The SVR operation, as performed in our institution, is Since the first description by Dor, the procedure has been conducted on the heart arrested with antegrade crystalloid, adopted by many surgeons, but its use is it is not widespread or cold blood cardioplegia introduced in 2001. CABG is because surgeons have been unwilling to incise and exclude performed first, as completely as possible, almost always the akinetic segments that may appear normal on the surface; on the left anterior descending coronary artery to preserve this finding is often encountered after successful early reper- the upper part of the septum and to guarantee complete fusion that savages the epicardial and myocardial layers but revascularization. The LV is opened in the middle of the the scar remains in the subendocardial layer and is visible scar on the anterior wall, with an incision parallel to the left only if the ventricle is opened. The technique has not been anterior descending artery, starting from the mid portion standardized yet, and surgeons use essentially 4 variations towards the apex. The LV cavity is accurately checked and of LV reconstruction: linear closure by Jatene;10 modified thrombi are removed if present; the mitral valve is repaired, linear closure by Mickleborough et al;11 circular closure with when necessary, through the ventricular opening.14,15 Since a patch by Menicanti and Dor;12 and double circling closure 2001 we have been using a sizer/shaper device (Chase without a patch by O’Neill et al.13 These different techniques Medical, Richardson, TX, USA) filled to 50–60 ml/m2 to may all be successfully performed when the disease involves optimize the size and shape of the new ventricle (Figure 1). mainly the antero-apical wall, but when the septum is deeply The choice of 50 ml is made if the transverse diameter (as involved or the dilatation is only at the septal level, the taken below the mitral valve) is not very enlarged (<65 mm) original Dor technique is the only one that ensures complete and 60 ml is chosen if it is >65 mm. This choice is some- treatment of the underlying disease. To date, the technique what empirical, but we think that it is advisable to leave a described by Dor has been applied to all kinds of dilatation residual chamber with a normal volume (52±13 ml/m2 in a involving all segments (anterior, apical and septal). series of 52 normal subjects from our echocardiography More recently, Menicanti et al14 introduced the use of a lab).16 sizer/shaper intraventricular device as a refinement of the The Fontan suture is performed with the sizer inside the Dor technique, emphasizing the importance of re-shaping ventricle, following the conical curvature of the dummy, the LV cavity through patch positioning, which should be starting at the level of the new apex, going deep into the inserted deep in the septum and obliquely towards the aortic septum towards the aortic valve, in an oblique plane, flow tract in order to obtain an elliptical new cavity. The running towards the lateral wall and reaching again at the positioning of the patch follows the Fontan suture that is new apex.