Cutting the second order chords during mitral valve repair.

The chordae tendinae connect the papillary muscles (PMs) to the mitral valve. While the first-order chordae serve to secure the leaflets to maintain valve closure and prevent mitral valve prolapse, the second-order chordae are believed to play a role in maintaining normal left ventricle size and geometry. The PMs, from where the chordae tendinae originate, function as shock absorbers that compensate for the geometric changes of the left ventricular wall. The second-order chordae connect the PMs to both trigons under tension. The tension distributed towards the second-order chordae has been demonstrate to be more than threefold that in their first-order counterpart. Cutting the second-order chordae puts all the tension on the first-order chordae, which are then closer to their rupture point. However, it has been experimentally demonstrated that the tension at which the first-order chordae break is 6.8 newtons (N), by far higher than the maximal tension reached, that is 0.4 N. Even if the clinical reports have been favorable, the importance of cutting the second-order chordae to recover curvature of the anterior leaflet and increase the coaptation length between the mitral valve leaflets has been slowly absorbed by the surgical world. Nevertheless, there are progressive demonstrations that chordal tethering affects the anterior leaflet not only in secondary, but also in primary mitral regurgitation, having a not negligible role in the long-term outcome of mitral repair.

Acute iatrogenic complications after mitral valve repair.

BACKGROUND AND AIM OF THE STUDY: Mitral valve repair is the procedure of choice to correct mitral regurgitation. However, some dangerous iatrogenic complications can occur at the end of the procedure. Therefore, we sought to review the most frequent and clinically relevant acute iatrogenic complication following mitral valve repair. METHODS: A thorough review of the literature has been performed. Criteria for considering studies for this non-systematic review were as follows: observational and interventional studies investigating the acute iatrogenic complications following mitral valve repair, and essential review studies pertinent to the topic. RESULTS: The most frequent is the systolic anterior motion. Due to a systolic dislocation of the anterior leaflet toward the outflow tract, it causes both obstruction of the outflow tract and mitral regurgitation. Often it is due to excess of catecholamines or to reduced filling of the left ventricle but sometimes needs further surgical maneuvers, focused on moving posteriorly the coaptation line. It can be obtained by shortening the posterior leaflet or increasing the size of the ring or applying an Alfieri stitch to limit the movements of the anterior leaflet. Another complication, often underdiagnosed and potentially lethal, is the injury of the circumflex artery that happens at the level of the anterolateral commissure or P1 zone. Two mechanisms are involved. The first one is the direct injury of the artery by a stitch (roughly 25% of the patients present a distance artery-annulus <3 mm. The second one is the distortion of the artery, attracted toward the annulus by a misplaced stitch. The attraction causes kinking with stenosis of different degrees till functional occlusion. However, the artery has to be far from the annulus and the atrial tissue has to be stiff and resistant, as after an infective process, to move the circumflex artery toward the annulus without tearing. Positioning the stitches very close to the mitral leaflets in the dangerous area is the only prevention to the complication. The treatment in the operating theater is partial or total removal/reimplantation of the annular sutures or coronary artery bypass grafting to the circumflex area. If the injury is demonstrated only after coronary angiography, percutaneous revascularization can be attempted before further surgical treatment. CONCLUSIONS: Acute iatrogenic complication after mitral repair exists and may compromize patient outcome. Raising awareness about these issues, the precautions to prevent them, and the manners of resolution is therefore mandatory.

A morphofunctional analysis of the regurgitant mitral valve as a guide to repair: Another point of view.

Based on Carpentier's classification and principles, the techniques for mitral valve repair continue to evolve. We herein report our experience with the morphofunctional echocardiographic analysis of single mitral leaflets, as different anatomic features, even if conflicting, may coexist not only in the two leaflets but in the same leaflet as well. A classification is proposed, based on the length (normal, short, or long) and mobility (normal, restricted, or excessive) of mitral leaflets. The surgical techniques adopted for mitral valve repair are the direct consequence of this analysis.

Wrapping of the moderately dilated ascending aorta by fresh autologous pericardium.

BACKGROUND AND AIM OF THE STUDY: Wrapping of the ascending aorta (AA), isolated or associated with aortoplasty, has never been completely accepted. Some complications, as folding of the aortic wall, compression of the vasa vasorum and changes in the flow pattern, with consequent dilatation of the proximal arch, have been described. We used fresh autologous pericardium (FAP), so far never reported, to wrap the AA, with the aim to stabilize its size when moderately dilated, maintaining the preoperative dimension or limiting the reduction to a few millimeters. MATERIALS AND METHODS: From 2015 to 2019, 10 patients, who were operated on for valve or coronary surgery or both, underwent wrapping of the AA with FAP. Mean age was 69 ± 7 years and EuroSCORE II 3.5 ± 1.7. Four patients had moderately impaired ejection fraction (35%-49%). RESULTS: There was no early or late mortality. One patient was reoperated on after 48 months for severe mitral regurgitation. At a follow-up of 53 ± 14 months, a transthoracic echocardiogram showed that the AA size reduced slightly but significantly, from 45.2 ± 2.0 to 42.5 ± 4.1 mm, p = .03. The diameter of the proximal arch remained unchanged, from 37.1 ± 1.6 to 36.3 ± 2.9 mm, p = .20. CONCLUSIONS: In the presence of moderately dilated AA, wrapping can be a reasonable option. The use of FAP stabilizes the size of the aorta after a follow-up of 53 months. Maintaining a size similar to the preoperative one avoids the complications related to the procedure.

A historical appraisal of the techniques of left ventricular volume reduction in ischemic cardiomyopathy: Who did what?

Resection or exclusion of scars following a myocardial infarction on the left anterior descending artery territory started even before the beginning of the modern era of cardiac surgery. Many techniques were developed, but there is still confusion on who did what. The original techniques underwent modifications that brought to a variety of apparently new procedures that, however, were only a "revisitation" of what described before. In some case, old techniques were reproposed and renamed, without giving credit to the surgeon that was the original designer. Herein we try to describe which are the seminal procedures and some of the most important modifications, respecting however the merit of who first communicated the procedure to the scientific world.

Mitral valve repair for mitral regugitation in the elderly: Yes, we have to, but look at the etiologies!

The meta-analysis by Di Tommaso et al. demonstrated as elderly patients with mitral regurgitation (MR) undergoing mitral valve repair had lower short-term mortality and higher long-term survival with respect to patients undergoing mitral valve replacement. The benefit of repair is such, that initial surgical strategy is advisable in the elderly even in case of mild symptoms if compared with conservative management. However, even if repair can be performed in presence of some specific etiologies, as degenerative MR or secondary MR, there are always cases where a replacement can be an acceptable solution compared to a repair with uncertain future, regardless of our believes and our technical ability.

Left ventricular surgical remodeling 2.0.

Left ventricular surgical remodeling has been, for a long time, the procedure applied for large dyskinetic, or akinetic, areas as a consequence of a myocardial infarction, mainly located in the left anterior descending area. Many surgical techniques were developed, aimed to a pure reduction of the volume of the left ventricular (LV) cavity or to add to volume reduction a more physiologic conical shape. The expansion of interventional procedures invaded most of the fields before treated only by cardiac surgeons. In this issue, Pillay describes a hybrid technique, involving both interventional cardiologists and cardiac surgeons, aimed to LV volume reduction after an anterior myocardial infarction. A series of internal (right ventricular septum) and external (anterior wall) anchors are implanted to approximate the LV free wall to the anterior septum, consequently excluding the scarred myocardium. Although some limitations of this study, the authors have to be commended for having revitalized a procedure almost eliminated from the surgical scenario.