The era of the open correction.
Cooley et al in 1958 started the modern era of LVVR reporting the first case of linear resection of an anterolateral aneurysm using the cardiopulmonary bypass7 (fig. 1A,B), describing more cases soon after8. The Author used this technique extensively and his experience was of 1572 cases in 19819 and rose to 4298 in 199210. He started to treat the diskinetic septum using a dacron patch which replaced a diskinetic area with a smaller akinetic area9 (fig. 1C-E). It is noteworthy that the linear resection of the anterior wall with/out a patch on the septum includes the incredible work performed by Cooley among the techniques aimed to reduce the LV volume preserving the conical shape. The linear LV reconstruction was further developed by Mickleborough et al.11. The Authors, in presence of a scarred, thinned and aneurysmal septum, performed a septoplasty using a patch, part of which, differently from Cooley, was included in the final suture (fig. 2).
In 1973 Stoney et al reported 29 cases of anteroseptal ventricular aneurysms (the first case done most likely in 1971) where the technique of LVVR was completely original and conceptually different from what was done till then12. After the incision of the aneurysm, the junction of anterior scar tissue with the posterior viable myocardium was identified and the lateral edge of myocardium was then advanced down to the junction of scar and functioning myocardial tissue in the septum with a continuous suture line. Teflon strips were used to reinforce the lateral margin of the left ventricle, and the sutures were brought out through the septum to the anterior wall of the right ventricle. A second continuous suture line completed the closure (fig. 3). This is the first technique described in the literature where the septum was considered as important as the free wall. In the Introduction the Authors stated that “Conventional anterior aneurysmectomy in the past has confined excision and repair to diseased myocardium located to the left of the anterior descending coronary artery. Restudy of these patients in our institution has shown inadequate reduction of aneurysm size with residual akinetic myocardium remaining in the ventricular septum. Attempts to revascularize the anterior descending artery in patients with an anteroseptal aneurysm have been equally disappointing.”
A modification if this technique was introduced by Calafiore et al13 in 2003 who proposed, to make simpler the procedure, a direct suture of the border of the scar in the anterior wall to the border of the scar in the septum (linear septoexclusion, fig. 4A). If the resulting cavity was perceived to be too small, an elliptical patch could be used from the beginning of the septal scar to the new apex14 (septal reshaping, fig. 4B-D). Interestingly, the Authors referred to the Stoney technique as Guilmet technique15, as this latter Author redescribed in the 1984 the same procedure described by Stoney.
In 1985 Jatene reported 508 patients operated on between September 1977 to September 198316. His approach to the septum, intially similar to Cooley’s technique9, was changed. He used two or three mattress stitches buttressed with Teflon felt to reduce the elongation of the septal wall. But he was the first to introduce the concept of intracavitary purse string. It was placed on the free-wall endocardium at the junction of the endocardial scar and normal endocardium, never involving the papillary muscles. This free-wall suture was continued around the anterior base of the aneurysm until it reaches the junction of the anterior free-wall and anterior septum at the base of the aneurysm. The other end of the purse-string suture was continued onto the distal septum at the apex and then proximally up the anterior septum at its junction with the free-wall. Both ends of the purse-string suture were then passed transmurally through the anterior left ventricular free-wall and tied over a felt pledget. Because the purse-string suture was placed on the anterior edge of the septum and around the apex onto the free-wall, the septum was incorporated and remained a part of the wall of the left ventricular cavity. After the purse string has been tied, the opening could be closed, at the level of the purse string, with direct suture or with a patch (fig. 5). Jatene’s concept was revolutionary, as he introduced the concept of geometrical LV reconstruction, using a surgical intracavitary remodeling by a purse string associated with the treatment of the diskinetic septum, maintaining a conical LV shape. The use of a patch of a direct suture allowed to decide the volume of the cavity, even if this decision, according to the Author, was defined “empirical”.
In 1989 Dor proposed a technique that he started to use in 198417. The key points of the procedure were 1) resection of dyskinetic or akinetic LV free wall and thrombectomy when indicated; 2) dacron patch lined with pericardium secured at the junction of the endocardial muscle and scarred tissue, thereby excluding non-contractile portions of the LV and septum; 3) myocardial revascularization, in particular of the proximal LAD segments (fig. 6). To avoid excessive volume reduction, in 1999 Dor suggested to use a rubber balloon filled with water (50 to 70 ml/m²)18. As described initially, this technique was focused on volume reduction, as the patch was located at the base of the aneurysm and was as large as the base was, but the shape was often more rectangular than elliptic. The Dor procedure was initially perceived as functional amputation of the ventricle with exclusion of the entire akinetic or dyskinetic scar, leading to increased sphericity of the ventricle in some patients19. This consequence was considered irrelevant by Dor et al20, who stated that “The improvement of contractility is not related to shape. Although Buckberg and associates21 have suggested that a spherical cavity is less contractile than an elliptic one, the dogma of elliptic shape was established without convincing physical or physiologic data.” Nevertheless, this technique was widely applied, but faced a number of modifications that improved those perceived as weak points.
Cooley in 1989 published 6 cases with the same principles, but the excision of the free wall scar (which favored bleeding) was avoided. The scar was maintained and sutured over the patch, as it is done till now22.
An important modification was performed by Fontan23who suggested to reduce the size of the patch applying a purse string (the Fontan’s stitch) to limit the size to the normal size of the LV at the level of the insertion of the papillary muscles. The Author used an oval patch sized 25 to 30 mm, with 2-3 mm used for suturing. This variation was incorporated into the technique and is used till now.
Another important improvement was the use of a LV conical shaper introduced by Menicanti et al19 with two purposes. The first one was to avoid an excessive volume reduction, the second one was to maintain a shape as conical as possible. The volume of the shaper ranged from 60 to 75 ml/m² and the internal correction was completed with a patch (not larger than 30 mm) or with direct sutures over the shaper (fig. 7). In his later experience Menicanti et al24 reduced the volume to 50-60 ml/m².
The original Dor technique, as originally described, today does not exist anymore, as all the modifications changed substantially the surgical procedure.