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The chordae tendinae connect the papillary muscles 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 that they play a role in maintaining normal LV size and geometry. The papillary muscles, 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 three-fold that in the first-order counterpart. Cutting the second-order chordae puts all the tension on the first-order chordae, that can go closer to their rupture point. However, it has been experimentally demonstrated that the tension where the first-order chordae break is 6.8 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 increasing the coaptation length between the mitral leaflet 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 negligeable role in the long-term outcome of mitral repair.

RationaleThe presence of preformed antibodies against αGal in the human lead to opsonization of the implanted bioprosthetic heart valve (BHV), leading to deterioration and calcification. Murine subcutaneous implantation of BHVs leaflets has been widely used for testing the efficacy of anti-calcification treatments, however, unlike the situation in humans, leaflets implanted into a murine model will not be able to elicit an αGal immune response because both donor and recipient species constitutively express the epitope.ObjectiveThis study evaluates the calcium deposition on commercial BHV using a new humanized murine αGal knockout (KO) animal model. Furtherly, the anti-calcification efficacy of a polyphenol-based treatment was deeply investigated.Methods and ResultsBy using CRISPR/Cas9 approach an αGal KO mouse was created and used for the evaluation of the calcific propensity of original and polyphenols-treated BHV by subcutaneous implantation. The calcium quantification was carried out by plasma analysis; the immune response evaluation was performed by histology and immunological assays. Anti-αGal antibodies level in KO mice increases at least double after 2 months of implantation of original commercial BHV compared to WT mice, conversely, the polyphenols-based treatment seems to effectively mask the antigen to the KO mice’s immune system. Commercial leaflets explanted after 1 month from KO mice showed a four-time increased calcium deposition than what was observed on that explanted from WT. Polyphenol treatment prevents calcium deposition by over 99% in both KO and WT animals.ConclusionsThe implantation of commercial BHV leaflets significantly stimulates the KO mouse immune system resulting in massive production of anti-Gal antibodies and the exacerbation of the αGal-related calcific effect if compared with the WT mouse. The polyphenol-based treatment applied in this investigation showed an unexpected ability to inhibit the recognition of BHV xenoantigens by circulating antibodies completely preventing calcific depositions compared to the untreated counterpart.

Despite advances in technologies and clinical experience, conduction disorders, after transcatheter aortic valve replacement (TAVR) or surgical aortic valve replacement (SAVR), represent the weak point of these procedures, requiring permanent pacemaker implantation (PPI) till 37.7% of patients in TAVR recipients. The role of PPI in TAVR and SAVR remains controversial in mid- and long-term outcomes. Indeed, many studies have been published with contradictory results, leaving doubts rather than certainties.

The incidence of infective endocarditis in patients with bioprosthetic heart valves is over 100 times that of the general population with(1) the viability of 9 microorganisms strains (colony-forming units) and the infectivity degree of 3 viral strains (cellular infection capacity) were evaluated after suspension in the polyphenolic solution. (2) Leaflets from a treated and untreated commercial surgical valve model were incubated with a known concentration of(1) The polyphenolic solution proved to be effective in eliminating microorganisms strains guaranteeing the killing of at least 99.9%. The effectiveness is particularly relevant againstThe data suggest an interesting protective effect against infections and bacterial adhesiveness by a polyphenolic-based solution. Further studies will plan to extend the panel of microorganisms for the evaluation of the anti-adhesive effect; however, the use of optimized polyphenolic blends could lead to the development of new treatments capable to make transcatheter-valve substitutes more resistant to infection.

Fractional flow reserve (FFR) is the ratio of distal to proximal pressure during maximal hyperemia and indirectly estimates the blood flow across a stenotic coronary artery and the related degree of myocardial ischemia. Several studies have investigated the role of FFR in the setting of percutaneous myocardial revascularization and further research is ongoing. However, current evidence on FFR-guided surgical myocardial revascularization is controversial and limited. The main scientific interest is to clarify whether FFR-guided coronary artery bypass surgery is associated with clinical benefits in terms of mortality, myocardial infarction, major adverse cardiovascular events, minimally invasive surgical access compared with sternotomy and off-pump surgery. Furthermore some data suggest that conduit selection for coronary artery bypass grafting and surgical technique might be affected by FFR value. The aim of this article is to review the most recent available evidence about FFR-guided coronary artery bypass grafting and to discuss clinical implications and future perspectives.

Background MitraClip therapy (MCT) is becoming more popular to treat mitral regurgitation (MR) in high-risk patients. It is, however, expanding to lower risk patients with the idea that mitral valve (MV) repair can be performed if surgery will be necessary. We report our surgical experience in patients who underwent MCT and subsequently required MV surgery. Methods From February 2012 to September 2014, three patients out of 34 who underwent MCT (8.8%) needed surgery because of lesions resulting in new MR. Two of them had functional and the third one degenerative MR. Two patients with functional MR underwent emergency surgery for MV lesions adding a new severe MR, the third one, with degenerative MR, had surgery 377 days after MCT. Results The MV showed a perforation of the anterior leaflet in one case and P2 completely torn in the second case. MitraClip opening was difficult and caused further injury to the leaflets. The third case developed a severe MV stenosis. All three patients underwent MV replacement with a tissue valve. The postoperative course was uneventful and, after a mean of 14 months, all patients are alive and in NYHA class I or II. Conclusions The risk of urgent or elective surgery after MCT reduces the possibility of conservative surgery, as the possibility of valve reconstruction is less likely following the severe clip implantation-induced tissue damages. doi: 10.1111/jocs.12540 (J Card Surg 2015;30:414–418)

International audience; OBJECTIVE: To verify the rate of thromboembolic and hemorrhagic complications during the first 6 months after mitral valve repair and to assess whether the type of antithrombotic therapy influenced clinical outcome. METHODS: Retrospective data were retrieved from 19 centers. Inclusion criteria were isolated mitral valve repair with ring implantation. Exclusion criteria were ongoing or past atrial fibrillation and any combined intraoperative surgical procedures. The study cohort consisted of 1882 patients (aged 58 +/- 15 years; 36% women), and included 1517 treated with an oral anticoagulant (VKA group) and 365 with antiplatelet drugs (APLT group). Primary efficacy outcome was the incidence of arterial thromboembolic events within 6 months and primary safety outcome was the incidence of major bleeding within 6 months. Propensity matching was performed to obtain 2 comparable cohorts (858 vs 286). RESULTS: No differences were detected for arterial embolic complications in matched cohort (1.6% VKA vs 2.1% APLT; P = .50). Conversely, patients in the APLT group showed lower incidence of major bleeding complications (3.9% vs 0.7%; P = .01). Six-month mortality rate was significantly higher in the VKA group (2.7% vs 0.3%; P = .02). Multivariable analysis in the matched cohort found VKA as independent predictor of major bleeding complications and mortality at 6 months. CONCLUSIONS: Vitamin K antagonist therapy was not superior to antiplatelet therapy to prevent thromboembolic complications after mitral valve repair. Our data suggest that oral anticoagulation may carry a higher bleeding risk compared with antiplatelet therapy, although these results should be confirmed in an adequately powered randomized controlled trial

MitraClip therapy (MCT) is becoming more popular to treat mitral regurgitation (MR) in high-risk patients. It is, however, expanding to lower risk patients with the idea that mitral valve (MV) repair can be performed if surgery will be necessary. We report our surgical experience in patients who underwent MCT and subsequently required MV surgery.From February 2012 to September 2014, three patients out of 34 who underwent MCT (8.8%) needed surgery because of lesions resulting in new MR. Two of them had functional and the third one degenerative MR. Two patients with functional MR underwent emergency surgery for MV lesions adding a new severe MR, the third one, with degenerative MR, had surgery 377 days after MCT.The MV showed a perforation of the anterior leaflet in one case and P2 completely torn in the second case. MitraClip opening was difficult and caused further injury to the leaflets. The third case developed a severe MV stenosis. All three patients underwent MV replacement with a tissue valve. The postoperative course was uneventful and, after a mean of 14 months, all patients are alive and in NYHA class I or II.The risk of urgent or elective surgery after MCT reduces the possibility of conservative surgery, as the possibility of valve reconstruction is less likely following the severe clip implantation-induced tissue damages.

Background: Septoexclusion is a technique described by Guilmet in the mid 1980s. Its indications and midterm results are evaluated and compared to those obtained with the Dor operation. Methods: From January 1998 to April 2001, 79 patients had an exclusion of scars following myocardial infarction in left anterior descending artery (LAD) territory. Fifty of them (63.3%) had the Dor operation (Group D) and 29 (36.7%) the Guilmet operation (Group G). Dor technique was used when the involvement of the septum and the free wall was roughly similar. Guilmet technique was indicated when the septum was involved at a greater extent than the free wall. Ejection fraction (EF) was lower and end-diastolic volumes were higher in Group G. Incidence of functional mitral regurgitation was similar in both groups. Results: Thirty-day mortality was 7.6% (8.0% in Group D versus 6.9% in Group G,p = ns). After a mean of21.0 ± 8.5months, five patients (6.9%) died, two in Group D and three in Group G. Causes of death were cardiac related in four and not cardiac related in one. Mean follow-up of the 68 survivors was24.3 ± 12.0months (range: 4-38 months). Fifty patients (73.5% of the survivors) improved (28 in Group D and 22 in Group G,p = 0.026), whereas in 18, New York Heart Association (NYHA) class remained unchanged or worsened. Both groups showed an increase of EF and a volumetric reduction, whereas stroke volume remained unchanged. Fewer patients had mitral regurgitation than in the preoperative period (41.3% versus 65.8%, p = 0.013) and at a lesser extent (1.7 ± 0.7versus0.7 ± 0.6, p < 0.001). Conclusions: Our results show that both Dor and Guilmet techniques are effective in the surgical treatment of left ventricular dyskinetic or akinetic areas related to LAD territory. Each technique has its own indications and has to be addressed to patients with different extension of septal scars.(J Card Surg 2003;18:93-100)

Mitral valve (MV) is composed of several structures working in synchrony to open during diastole and close in systole within the high-pressure systemic environment. Its morphological features ensure a normal leaflet closure that prevents regurgitation of blood back into the left atrium causing loss of ventricular pressure and forward flow. The complex interactions of the normal MV are reliant on each component playing a complete role for the efficient working of the valve. In this review we firstly discuss the overall MV structure in terms of a complex make up of the annulus, the leaflets, their tendinous cords, and the supporting papillary muscles, and then the anatomical changes of each MV components due to left ventricular geometry and function alterations, underlying functional mitral regurgitation.

Left ventricular (LV) aneurysm is a complication of an acute myocardial infarction (AMI). Herein a new technique is described that is indicated when the postinfarctual scar involves the septum more than the free wall. The incision starts at the apex and is directed, parallel to LAD, toward the base of the heart. The septum is rebuilt using 1 or 2 U-stitches, passed from inside, to join the anterior wall to the septum. The starting point begins as high as the scar, maintaining an oblique direction toward the new apex. An oval dacron patch is then sutured from the septum (end of the direct suture through the border with the inferior septum) to the anterior wall (between the healthy and the scarred wall) up to the new apex. Thirty-day mortality is low. This procedure provides good midterm results. New York Heart Association class improved from 2.7±0.9 to 1.6±0.5 (P≪0.001). Left ventricle (end-diastolic and end-systolic) volume, reduced significantly. Stroke volume normalized and ejection fraction increased even if not significantly. Mitral regurgitation reduced significantly from 2.5 to 0.6. No new mitral regurgitation developed.

Off-pump coronary artery bypass surgery is widely performed because of its proved safety, but its effectiveness remains controversial. The aim of this retrospective study was to compare early and late results in patients with multivessel disease, operated on off-pump and on-pump.From November 1994 to December 2001, 2957 patients with multivessel disease underwent isolated coronary revascularization, on-pump (n = 1924) and off-pump (n = 1033). Sixty-five patients (2.2%) who were converted from off-pump to on-pump were considered as part of the off-pump group.Stepwise logistic regression analysis showed that the use of cardiopulmonary bypass was an independent predictor for early death, early negative primary endpoints, and early major events. Conversion to on-pump was an independent risk factor for a higher incidence of death due to any cause and cardiac death, early negative primary endpoints, and early major events. Conversion, however, did not affect late clinical outcome. The 6-year freedom from death (any cause, cardiac cause), myocardial infarction, redo/coronary angioplasty and any events was similar in the two groups.These results suggest that off-pump surgery reduces early mortality and morbidity. These benefits are not at the expense of the long-term clinical outcome which seems to be similar in the two groups. Patients who require conversion from off-pump to on-pump have a much higher mortality and morbidity although this does not seem to influence their long-term clinical outcome.

We evaluated our experience to investigate if the use of bilateral internal mammary artery (BIMA) grafting, with or without complementary saphenous vein grafts (SVGs), if compared to the use of single IMA and SVG(s), increases the quality of the results of coronary bypass grafting in patients younger than 75 years who undergo first myocardial revascularization.From September 1986 to December 1999, 1602 patients younger than 75 years underwent first myocardial revascularization using left internal mammary (LIMA) to left anterior descending (LAD) and SVG(s) (n=576) or BIMA (one IMA on the LAD) with or without SVG(s) (n=1026). Propensity score analysis was used to select 1140 patients with the same preoperative and operative characteristics. Thirty day outcome was evaluated as well as 10-year freedom from death by any cause, cardiac death, acute myocardial infarction (AMI), AMI in a grafted area (GA), redo/PTCA, redo/PTCA in a GA, target cardiac events (death from cardiac cause, AMI in a GA, redo/PTCA in a GA), and any event. Follow-up ranged from 3.5 to 16.8 years (mean 7.3+/-4.8 years).Thirty day mortality was 2.8% in Group LIMA and 2.1% in Group BIMA, P n.s.; incidence of major complications was, respectively, 7.0 versus 5.4%, P n.s. Group BIMA showed better 10-year freedom from cardiac death (96.5+/-0.8 versus 91.3+/-1.4, P=0.0288), AMI (98.0+/-0.6 versus 94.3+/-1.2, P=0.0180), AMI in a GA (98.4+/-0.6 versus 94.7+/-1.1, P=0.0057) and target cardiac events (93.9+/-1.1 versus 86.3+/-1.8, P=0.0388). Cox analysis confirmed that LIMA+SV(s) was an independent risk factor from lower freedom from cardiac death, AMI, AMI in a GA and cardiac events.As freedom from cardiac events is a main target of any revascularization procedure, we think that, when a patient undergoes a first coronary surgery and is younger than 75 years, BIMA grafting should not be denied, especially if his life expectancy is higher than 10 years.

The impact of myocardial revascularization without cardiopulmonary bypass (CPB) was evaluated in a series of consecutive patients with multivessel disease.From May 21, 1997 to November 30, 2000, 1,843 consecutive patients underwent isolated myocardial revascularization. From this total, 919 patients were done without CPB (group A, 49.9%) and 924 patients were done with CPB (group B, 50.1%). Patients that converted from without CPB to with CPB were included in group A. Thirty-three variables were evaluated with univariate and multivariate analysis to identify the independent variables predictive of higher incidence of early mortality, acute myocardial infarction, cerebrovascular accident, and early major events.Early mortality was 2.2% (group A, 1.4%; group B, 3.0%; p = 0.016), acute myocardial infarction incidence was 1.8% (group A, 1.1%; group B, 2.6%; p = 0.027), cerebrovascular accident incidence was 0.9% (group A, 0.8%; group B, 1.0%; p = not significant), and early major events incidence was 6.7% (group A, 5.3%; group B, 8.2%; p0.001). Stepwise logistic regression analysis showed that CPB was an independent risk factor for higher mortality (odds ratio, 2.2; p = 0.0217), higher incidence of acute myocardial infarction (odds ratio, 2.5; p = 0.0185), and higher incidence of early major events (odds ratio, 1.8, p = 0.0034).When CPB was not used, patients experienced lower early mortality and incidences of acute myocardial infarction were less complicated, both at univariate analysis and stepwise logistic regression analysis.