Predictive factors of long-term results following valve repair in ischemic mitral valve prolapse

Distinctive Signs of Disease as Deterrents for the Endothelial Function: A Systematic Review

Endothelial integrity plays a major role in homeostasis and is responsive to the numerous endogenous factors released. While its functional role in vascular tone is well described, its role in the pathophysiology of cardiovascular disease is of interest as a potential therapeutic target. We performed a systematic review to provide an overview of new therapeutic and diagnostic targets for the treatment of coronary artery disease related to endothelial dysfunction. Databases of PubMed, Ovid’s version of MEDLINE, and EMBASE were interrogated with appropriate search terms. Inclusion criteria have been met by 28 studies that were included in the final systematic review. We identified inflammation, pulmonary hypertension, diabetes mellitus and Fabry disease as pathophysiological mechanisms and explored the therapeutic options related to these conditions including medications such as Canakinumab. Endothelial dysfunction has a key role in several different pathophysiological processes which can be targeted for therapeutic options. Ongoing research should be targeted at making the transition to clinical practice. Further research is also needed on understanding the amelioration of endothelial dysfunction with the use of cardiovascular medications.

Impact of Mitral Regurgitation Recurrence on Mitral Valve Repair for Secondary Ischemic Mitral Regurgitation

OBJECTIVES

The current guidelines still do not include specific recommendations on the use of subvalvular repair (SV-r) for treatment of ischemic mitral regurgitation (IMR). Therefore, the objective of our study was to evaluate the clinical impact of mitral regurgitation (MR) recurrence and ventricular remodeling on long-term outcomes after SV-r combined with restrictive annuloplasty (RA-r).

METHODS

We performed a subanalysis of the papillary muscle approximation trial, studying 96 patients with severe IMR and coronary artery disease undergoing restrictive annuloplasty alongside subvalvular repair (SV-r + RA-r group) or restrictive annuloplasty alone (RA-r group). We analyzed treatment failure differences, the influence of residual MR, left ventricular remodeling, and clinical outcomes. The primary endpoint was treatment failure (composite of death; reoperation; or recurrence of moderate, moderate-to-severe, or severe MR) within 5 years of follow-up after the procedure.

RESULTS

A total of 45 patients showed failure of the treatment within 5 years, of which 16 patients underwent SV-r + RA-r (35.6%) and 29 underwent RA-r (64.4%, p = 0.006). Patients with significant residual MR presented with a higher rate of all-cause mortality at 5 years compared with trivial MR (HR 9.09, 95% CI 2.08-33.33, p = 0.003). MR progression occurred earlier in the RA-r group, as 20 patients in the RA-r group vs. 6 in SV-r + RA-r group had a significant MR 2 years after surgery (p = 0.002).

CONCLUSIONS

RA-r remains a surgical mitral repair technique with an increased risk of failure and mortality at 5 years compared with SV-r. The rates of recurrent MR are higher, and recurrence occurs earlier, with RA-r alone compared to SV-r. The addition of the subvalvular repair increases the durability of the repair, thus extending all of the benefits of preventing MR recurrence.

Anomalous origin of the left coronary artery from the pulmonary artery as a rare cause of mitral valve prolapse: a case report

BACKGROUND

 Mitral valve prolapse (MVP) is an etiologically heterogeneous disorder. Early diagnosis and prompt treatment of the underlying disease are of great significance. Herein, we present a rare case of MVP caused by anomalous origin of the left coronary artery from the pulmonary artery (ALCAPA).

CASE PRESENTATION

A 22-year-old female presented with a 16-year history of anterior mitral leaflet prolapse. However, she had never experienced any discomfort before. At a routine follow-up, a transthoracic echocardiogram showed anterior mitral leaflet prolapse (A2) with moderate mitral regurgitation, and a retrograde blood flow from an extremely dilated left coronary artery (LCA). Further coronary angiography and coronary computed tomography angiography confirmed the diagnosis of ALCAPA. She subsequently underwent successful LCA reimplantation and concomitant mitral valve replacement. Intraoperatively, her mitral annulus was mildly dilated, anterior mitral valve leaflet appeared markedly thickened with rolled edges, and a chordae tendineae connecting the anterior leaflet (A2) was ruptured and markedly shortened.

CONCLUSIONS

ALCAPA is a rare and potentially life-threatening congenital coronary artery anomaly that may cause mitral valve prolapse. Echocardiogram is an important screening tool for this disorder.

Late durability of mitral repair for ischemic versus nonischemic functional mitral regurgitation

BACKGROUND

Concerns regarding long-term durability of surgical repair for functional mitral regurgitation are based on short-term data, with few comparisons of ischemic (IMR) versus non-ischemic (NIFMR) etiology.

METHODS

788 consecutive patients receiving mitral repair for functional mitral regurgitation were evaluated from a prospectively maintained database. Patients with other surgical procedures were included. Propensity score matching was used to compare outcomes in IMR versus NIFMR.

RESULTS

Unmatched IMR patients tended to be older men with greater comorbidities. 198 matched pairs of IMR versus NIFMR patients had similar demographics with relatively preserved ejection fraction 40±13% and end-systolic diameter 4.3±1.1cm. Concomitant coronary revascularization occurred in 70% of matched IMR patients. All patients received an annuloplasty ring, usually 24-26 mm. Heart failure class improved from 2.8 preop to 1.5 at 5 years (P<0.0001). Survival at 15 years was worse with IMR (12±3% v 43±5%, P<0.0001). At 10 years, cumulative incidence of moderate or more (>=2+) mitral regurgitation (27±4% v 26±4%, P=0.4), severe regurgitation (10±3% v 8±2%, P=0.5), and mitral reoperation (3±1% v 3±1%, P=0.4) were not different between IMR v NIFMR. Recurrent moderate regurgitation was associated with heart failure readmission but not with mortality.

CONCLUSIONS

In propensity-matched patients, IMR versus NIFMR had worse survival but similar repair durability, with moderate regurgitation in 27% at 10 years and rare severe regurgitation or mitral reoperation. In selected patients with relatively preserved function, mitral repair for IMR or NIFMR can improve symptoms with durable mild regurgitation in most patients out to 10 years.

Exploring the Operative Strategy for Secondary Mitral Regurgitation: A Systematic Review

Background

Mitral valve disease surgery is an evolving field with multiple possible interventions. There is an increasing body of evidence regarding the optimal strategy in secondary mitral regurgitation where the pathology lies within the ventricle. We conducted a systematic review to identify the benefits and limitations of each surgical option.

Methods

A systematic review of the literature was performed to identify pertinent randomized controlled trials (RCTs), propensity-matched observational series, and meta-analyses which were considered initially and followed by unmatched observational series using the MEDLINE, Ovid EMBASE, and Cochrane Library.

Results

We identified 6 different strategies for treating secondary mitral valve regurgitation: mitral valve replacement, restrictive mitral annuloplasty, surgical revascularization (with and without mitral annuloplasty), subvalvular procedures (papillary muscle approximation, papillary muscle relocation, ring and string procedure), and procedures directly targeting the mitral valve (edge-to-edge repair and anterior leaflet enlargement) alongside transcatheter heart valve therapy. We also highlighted the role of left ventricular assist devices in the management of this condition. The benefits and limitations of each intervention are highlighted.

Conclusion

There is currently no unanimous and shared strategy for the optimal treatment of patients with secondary IMR. The management of patients with secondary mitral regurgitation must be entrusted to a multidisciplinary Heart Team to ensure ideal intervention and patient matching for the best outcomes.

Recent insights into pathophysiology and management of mechanical complications of myocardial infarction

PURPOSE OF REVIEW

Mechanical complications of myocardial infarction are a group of postischemic events and include papillary muscle rupture resulting in ischemic mitral regurgitation, ventricular septal defect, left ventricle free wall rupture, pseudoaneurysm, and true aneurysm. Advances made in management strategies, such as the institution of 'Code STEMI' and percutaneous interventions, have lowered the incidence of these complications. However, their presentation is still associated with increased morbidity and mortality. Early diagnosis and appropriate management is crucial for facilitating better clinical outcomes.

RECENT FINDINGS

Although the exact timing of a curative intervention is not known, emerging percutaneous and transcatheter approaches and improving mechanical circulatory support (MCS) devices have greatly enhanced our ability to manage and treat some of the complications postinfarct.

SUMMARY

Although the incidence of mechanical complications of myocardial infarction has decreased over the past few decades, these complications are still associated with high rates of morbidity and mortality. The combination of early and accurate diagnosis and subsequent appropriate management are imperative for optimizing clinical outcomes. Although more randomized clinical trials are needed, mechanical circulatory support devices and emerging therapeutic strategies can be offered to carefully selected patients.

The Use of Radial Artery for CABG: An Update

We used the radial artery as a second target conduit for coronary artery bypass grafting since 1971. However, randomized clinical studies have demonstrated differences in clinical outcomes between the radial artery and other grafts because these trials are underpowered. As we proceed toward 50 years of experience with radial artery grafting, we examined the literature to define the best second-best target vessel for coronary artery bypass grafting. The literature was reviewed with emphasis, and a large number of randomized controlled trials, propensity-matched observational series, and meta-analyses were identified with a large patient population who received arterial conduit and saphenous vein grafts. The radial artery has been shown to be effective and safe when used as a second target conduit for coronary artery bypass grafting. Results and patency rates were superior to those for saphenous vein grafting. It has also been shown that the radial artery is a safe and effective graft as a third conduit into the territory of the artery right coronary artery. However, there is little evidence based on a few comparable series limiting the use of the gastroepiploic artery. In its fifth decade of use, we can finally deduced that the aorto-to-coronary radial bypass graft is the conduit of choice for coronary operations after the left internal thoracic artery to the left anterior descending artery.

Ischemic functional mitral regurgitation: from pathophysiological concepts to current treatment options. A systemic review for optimal strategy

OBJECTIVE

The current treatment of ischemic functional mitral regurgitation (FMR) remains debated due to differences in inclusion criteria of randomized studies and baseline characteristics. Also, the role of left ventricular pathophysiology and the role of subvalvular apparatus have not been thoroughly investigated in recent literature.

METHODS

A literature search was performed from PubMed inception to June 2020.

RESULTS

Novel concepts of pathophysiology, such as the proportionate/disproportionate conceptual framework, the role of papillary muscles and left ventricular dysfunction, the impact of myocardial ischemia and revascularization, left ventricular remodeling, and the effect of restrictive annuloplasty or subvalvular procedures have been reviewed.

CONCLUSIONS

The clinical benefits associated with the use of MitraClip is more evident in patients with disproportionate FMR with greater and sustained left ventricular reverse remodeling. Importantly, in the absence of myocardial revascularization, expansion of myocardial scar tissue and non-perfused areas of ischemic myocardium occur with time, and this impact on outcomes with a longer follow-up period cannot be quantified. In advanced phases of FMR, neither mitral ring annuloplasty nor percutaneous therapies could significantly modify the established pathoanatomic alterations.

Transcatheter closure for the treatment of pseudoventricular aneurysm after acute myocardial infarction: a case report

Left ventricular free wall rupture (LVFWR) is a rare but lethal complication of acute myocardial infarction (AMI). Urgent surgery is essential but associated with high postoperative mortality. Even worse, LVFWR patients may experience sudden death without a chance for surgery. In this article, we report our successful transcatheter closure of a patient with the most extensive pseudoventricular aneurysm after AMI reported thus far. Cardiac magnetic resonance imaging (MRI) revealed a giant pseudoventricular aneurysm located in the inferior and lateral walls of the left ventricle; the rupture diameter was 28 mm, and the maximum tumor diameter was 90.2 mm. We used transcarotid approach (TCA) and atrial septal defect closure umbrella to complete the operation, which solved the lack of special interventional instruments to treat pseudoventricular aneurysm after AMI. In addition, we still needed to treat liver and kidney failure caused by hemolysis after operation, and undergone strict follow-up. In conclusion, transcatheter closure is practical and feasible for the treatment of pseudoventricular aneurysm after AMI, although hemolysis and decline of cardiac pumping function after the successful interventional treatment deserve special attention. Future multicenter studies are required to identify patients best suited for interventional treatment timing. And further developments in devices and delivery techniques are required in order to optimize interventional outcomes.

Long Term Survival After Surgery for Ischaemic Mitral Regurgitation: A Single Centre Australian Experience

BACKGROUND

Ischaemic mitral regurgitation (IMR) is associated with an increase in both mortality and congestive heart failure in patients undergoing coronary artery bypass grafting (CABG). Intervention for moderate to severe IMR involves either valve repair or replacement. The ideal option is yet to be fully defined with relatively poor long-term survival being noted in the literature.

METHOD

A retrospective observational study was conducted to review the outcomes of patients undergoing CABG in combination with either mitral valve repair (MVr) or mitral valve replacement (MVR) for concurrent coronary artery disease with moderate to severe IMR at The Prince Charles Hospital in Brisbane between the years 2002 to 2015.

RESULTS

One hundred and five (105) patients were included, 81 patients (77%) undergoing CABG and MVr and 24 patients (23%) undergoing CABG and MVR. There was no difference in 30-day mortality between the two groups (1% in MVr and 0% in MVR, p=0.589), however patients in the MVr group were significantly more likely, in univariate and multivariate analysis, to develop at least moderate MR (40% v. 8%, p=0.006). The 5-year survival was 87% and 55% at 10 years.

CONCLUSIONS

In patients undergoing CABG and mitral valve intervention for IMR, long-term mortality remains high. There was no difference in short- or long-term mortality between repair and replacement although recurrence of at least moderate mitral regurgitation was significantly higher with mitral valve repair.

Mitral regurgitation: lessons learned from COAPT and MITRA-Fr

Recent studies about percutaneous treatment of secondary mitral regurgitation (MR) underlined the importance of left ventricular geometry and features of mitral valve as determinants of procedural and long-term success. Guideline-directed medical therapy (GDMT), transcatheter mitral valve treatment (TMVT) and surgical procedures (mitral valve replacement, mitral valve repair at level of the annulus or subvalvular apparatus) have been extensively evaluated but not adequately compared in current clinical studies. A detailed analysis of the results of the study about transcatheter mitral valve repair would allow to evaluate the safety and effectiveness of such procedure and would provide potential indications for improving the quality of percutaneous and surgical repair in patients with moderate-to-severe secondary MR. Patients with proportionate MR (i.e., MR severity is proportional to the amount of left ventricular dilatation) are prone to respond to the optimization of medical therapy, while patients with disproportionate MR (i.e., MR severity is disproportionately higher than predicted by left ventricular dilatation, with high EROA and small left ventricle) are likely to benefit from additional repair. The identification of specific subpopulation of "high responders", based on the anatomic characteristics of the mitral valve and the relative dimensions of the annulus, the regurgitation and the left ventricle, can also apply to medical therapy. However, some pivotal component of MR (such as the symmetry of tethering and the differences in biomechanical features of leaflets) are not adequately investigated in current studies and warrant further evaluation.

[Long-Term Survival of Patients with Ischemic Heart Disease After Surgical Correction of Moderate Ischemic Mitral Regurgitation]

AIM

to assess effect of correction of moderate ischemic mitral regurgitation (IMR) in patients with ischemic cardiomyopathy (IMC) in immediate and remote period.

MATERIALS AND METHODS

We included in a single center prospective study 76 patients with IMC, left ventricular ejection fraction ≤35 %, and moderate IMR. Patients with indications to postinfarction aneurism repair were not included. For randomization we used the method of envelopes. Thirty-eight patients were randomized in the group where coronary artery bypass grafting (CABG) was combined with of mitral valve repair (MVR), and 38 patients in the control group of isolated CABG. Mean age of patients was 57±8 (from 30 to 75 лет) years. For IMR correction we used rigid MEDENG ring. Results. Inhospital mortality was 5.4 % (n=2) after isolated CABG and 10.81 % (n=4) after CABG + MVR. Main cause of death was acute heart failure. One- and 2‑year survival was 84 and 78 %, respectively, after CABG+MVR, and 84 and 71 % after isolated CABG. There was significant difference in three-year survival between groups (hazard ratio [HR] of death 0.457, p=0.04). Five-year survival was 45 and 74 % after isolated CABG and CABG+MVR, respectively (р=0.037). Factors associated with inhospital mortality were pulmonary hypertension (HR 2.177, 95 % confidence interval [CI] 2.299 to 9.831; p=0.043), NYHA class IV chronic heart failure (HR 3.027, 95 % CI 1.605 to 5.707; р=0.001), negative result of stress test echocardiography (HR 0.087, 95 %CI 0.041 to 0.186; р&lt;0.001), atrial fibrillation (HR 4.754, 95 %CI 2.299 to 9.831; р&lt;0.001).

CONCLUSION

Correction of moderate IMR in patients with IMC leads to improvement of parameters of survival in remote period. Five-year survival after isolated CABG was 45 %, while after CABG+MVR - 74 % (р=0.037).

Clinical manifestations, diagnosis, and treatment of ischemic mitral regurgitation: a review

Ischemic mitral regurgitation (IMR) is a frequent complication after acute myocardial infarction (AMI) associated with a worse prognosis. The pathophysiological mechanisms of IMR are not fully understood, but it is known to be a complex process in which ventricular remodelling is the main causal factor. The various imaging techniques in cardiology and echocardiography fundamentally have contributed significantly to clarify the mechanisms that cause and progressively aggravate IMR. At present, different therapeutic options, the most important of which are cardio-surgical, address this problem. Nowadays the improvement in cardiac surgery and transcatheter therapies, have shown a therapeutic advance in IMR management. IMR is a predictor of poor prognosis in patients with heart failure and depressed left ventricular (LV) systolic function. However, it remains controversial whether mitral regurgitation (MR) in these patients is a consequence of dilation and dysfunction of the LV, or whether it contributes to worsening the prognosis of the ventricular dysfunction. Given that echocardiography has a fundamental reference role in the identification, graduation of severity and evaluation of the therapeutics used in the treatment of MR, we are going to focus on it over the rest of the imaging techniques. In contrast to primary MR the benefits of mitral surgery in patients with secondary MR are uncertain. Therefore, we will comment fundamentally on the role of mitral surgery in patients with IMR, with an update of the different surgical interventions available, without forgetting to mention the other therapeutic options currently available.

Biomechanics raises solution to avoid geometric mitral valve configuration abnormalities in ischemic mitral regurgitation

Ischemic mitral regurgitation (IMR) is a form of mitral insufficiency that is characterized by papillary muscle (PM) displacement, leaflet tethering, reduced closing forces, and different degree of annular dilatation. Treatment of this condition includes mitral valve replacement or mitral valve repair with restrictive annuloplasty. Recent evidences in mitral valve repair showed that addressing only the annulus and neglecting the subvalvular apparatus provides a suboptimal operation with poor long-term results. However, the complexity of the geometrical aberrances occurring in IMR demands for more accurate analysis also involving the biomechanics underlying the failing mitral valve and subvalvular apparatus. Finite element analysis (FEA) is a powerful tool in this context and we developed a biomechanical model of mitral valve and subvalvular unit using 3D geometry of the leaflets, annulus, chordae and PM. After the application of structural properties of materials to these elements and simulation of systemic pressure loading, FEA could be used to directly determine biomechanical changes and geometry variations. We believe this approach can provide valuable information to better address the surgical treatment of IMR and answer some of the questions still pending in IMR management.

Ischemic mitral valve prolapse

Ischemic mitral prolapse (IMP) is a pathologic entity encountered in about one-third among the patients undergoing surgery for ischemic mitral regurgitation (IMR). IMP is generally the result of a papillary muscle injury consequent to myocardial, but the recent literature is progressively unveiling a more complex pathogenesis. The mechanisms underlying its development regards the impairment of one or more components of the mitral apparatus, which comprises the annulus, the chordae tendineae, the papillary muscle and the left ventricular wall. IMP is not only a disorder of valvular function, but also entails coexistent aspects of a geometric disturbance of the mitral valve configuration and of the left ventricular function and dimension and a correct understanding of all these aspects is crucial to guide and tailor the correct therapeutic strategy to be adopted. Localization of prolapse, anatomic features of the prolapsed leaflets and the subvalvular apparatus should be carefully evaluated as also constituting the major determinants defining patient's outcomes. This review will summarize our current understanding of the pathophysiology and clinical evidence on IMP with a particular focus on the surgical treatment.