Ischemic Versus Degenerative Mitral Regurgitation: Does Etiology Affect Survival?

Socioeconomic disparities in midterm outcomes after repair for degenerative mitral regurgitation

OBJECTIVE

The influence of socioeconomic disparities on survival after mitral repair is poorly defined. We examined the association between socioeconomic disadvantage and midterm outcomes of repair in Medicare beneficiaries with degenerative mitral regurgitation.

METHODS

US Centers for Medicare and Medicaid Services data were used to identify 10,322 patients undergoing isolated first-time repair for degenerative mitral regurgitation between 2012 and 2019. Zip code-level socioeconomic disadvantage was dichotomized with the Distressed Communities Index, which incorporates education level, poverty, unemployment, housing security, median income, and business growth; those with Distressed Communities Index score ≥80 were classified as distressed. The primary outcome was survival, censored at 3 years. Secondary outcomes included cumulative incidences of heart failure readmission, mitral reintervention, and stroke.

RESULTS

Of the 10,322 patients undergoing degenerative mitral repair, 9.7% (n = 1003) came from distressed communities. Patients from distressed communities underwent surgery at lower volume centers (11 vs 16 cases/year) and traveled further for surgical care (40 vs 17 miles) (both P values < .001). At 3 years, unadjusted survival (85.4%; 95% CI, 82.9%-87.5% vs 89.7%; 95% CI, 89.0%-90.4%) and cumulative incidence of heart failure readmission (11.5%; 95% CI, 9.6%-13.7% vs 7.4%; 95% CI, 6.9%-8.0%) were worse in patients from distressed communities (all P values < .001), whereas mitral reintervention rates were similar (2.7%; 95% CI, 1.8%-4.0% vs 2.8%; 95% CI, 2.5%-3.2%; P = .75). After adjustment, community distress was independently associated with 3-year mortality (hazard ratio, 1.21; 95% CI, 1.01-1.46) and heart failure readmissions (hazard ratio, 1.28; 95% CI, 1.04-1.58).

CONCLUSIONS

Community-level socioeconomic distress is associated with worse outcomes in degenerative mitral repair among Medicare beneficiaries.

Prosthetic choice in mitral valve replacement for severe chronic ischemic mitral regurgitation: Long-term follow-up

BACKGROUND

Prosthetic choice for mitral valve replacement is generally driven by patient age and patient and surgeon preference, and current guidelines do not discriminate between different etiologies of mitral valve disease. Our objective was to assess and compare short- and long-term outcomes after mitral valve replacement among patients with biological or mechanical prostheses in the setting of severe ischemic mitral regurgitation.

METHODS

Between 2000 and 2016, 424 patients underwent mitral valve replacement for severe ischemic mitral regurgitation at our institution, using biological prosthesis in 188 (44%) and mechanical prosthesis in 236 (56%). A 1:1 propensity score match (n = 126 per group) and inverse probability of treatment weighting were used to compare groups. Short-term outcomes included in-hospital mortality and other cardiovascular adverse events. Long-term outcomes included survival and hospital readmission for cardiovascular causes, stroke, and major bleeding.

RESULTS

In-hospital mortality and early postoperative adverse events were similar between groups in the propensity score match and inverse probability of treatment weighting cohorts. Overall long-term survival was similar at 5 and 9 years, but mechanical prosthesis recipients were more frequently readmitted to hospital for cardiovascular causes, including stroke and non-neurological bleeding in propensity score matching and inverse probability of treatment weighting analyses (all P values < .004). Type of prosthesis did not independently influence all-cause mortality (hazard ratio, 1.01; 95% confidence interval, 0.71-1.43; P = .959), but placement of a mechanical prosthesis was associated with increased risk of readmission for cardiovascular events (hazard ratio, 1.65; 95% confidence interval, 1.17-2.32; P = .004) among matched patients.

CONCLUSIONS

The type of prosthesis has no influence on long-term survival among patients with severe ischemic mitral regurgitation undergoing mitral valve replacement. There may be an increased risk of neurologic events and serious bleeding associated with mechanical prostheses.

Left Atrial Remodeling and Dysfunction in Swine Models of Mitral Regurgitation

BACKGROUND

Left atrial (LA) dysfunction is one of the predictive factors of worse outcomes after mitral valve surgery for mitral regurgitation (MR). We aimed to investigate the effect of MR etiology on progression of LA remodeling in swine MR models.

METHODS

MR was induced in 14 Yorkshire pigs using catheter-based procedures. Seven pigs underwent simultaneous occlusions of the left circumflex artery and the diagonal branch, which resulted in ischemic MR (IMR group). The other seven pigs underwent chordal severing to induce leaflet prolapse simulating degenerative MR (DMR group). Changes in LA volume and function were assessed at baseline, 1 and 3 months using echocardiography and hemodynamic evaluations. Histopathological assessments were conducted to evaluate LA hypertrophy and fibrosis.

RESULTS

At 3 months, quantitative MR severity was comparable and severe in both groups. Despite the similar degree of MR, minimum LA volume index increased significantly more in the IMR group (IMR: 11.9±6.4 to 73.2±6.4, DMR: 10.7±6.4 to 29.5±6.4 ml/m², p_interaction=0.004). Meanwhile, increase in maximum LA volume index was similar between the groups, resulting in lower LA emptying function in the IMR group (IMR: 60.1±3.1 to 29.4±3.1, DMR: 62.4±3.1 to 58.2±3.1%, p_interaction=0.0003). LA reservoir strain assessed by echocardiography was also significantly lower in the IMR group. Histological analyses revealed increased LA cellular hypertrophy and fibrosis in the IMR group.

CONCLUSIONS

Ischemic MR is associated with aggressive remodeling and reduced emptying function compared to MR due to leaflet prolapse. Earlier intervention might be necessary for ischemic MR to prevent LA remodeling.

Clinical and Echocardiographic Predictors of Reduced Survival in Patient with Functional Mitral Regurgitation

Functional mitral regurgitation (FMR) is associated with a poor outcome in patients with reduced left ventricular ejection fraction (LVEF). Two recent studies of percutaneous mitral valvular repair therapy reported disparate results, likely due in part to variable risk among FMR patients. The aim of this study is to define echocardiographic factors of prognostic significance in FMR patients, and particularly to compare ischemic and nonischemic FMR. We followed three hundred sixteen consecutive patients (age 60 ± 14 years, men 70%) with FMR and LVEF ≤ 35% between January 2010 and December 2015 (mean follow-up 3.7 years). Patients were categorized into ischemic (39.6%) and nonischemic (60.4%). MR was graded according to the American Society of Echocardiography guidelines. Although echo findings were similar between ischemic and nonischemic patient, the incidence of death, heart transplantation (HT), or LVAD implantation was higher in ischemic than in nonischemic patients (Log rank p = 0.001). In age and gender adjusted multivariate (11 variables) Cox regression analysis, left atrium volume index (LAVI) was associated with death, HT, or LVAD with hazard ratio of 2.1 for patients with FMR (p = 0.003). LAVI greater than 48.7 mL/m² predicts adverse outcome in both nonischemic and ischemic FMR (AUC 0.62, p < 0.001). Combined ischemic FMR with LAVI ≥ 48.7 mL/m² had the highest incident rate of all groups. In conclusion, despite similar LV function and MR severity, ischemic FMR patients had higher mortality than nonischemic patients. Of all echocardiographic parameters, an LAVI ≥ 48.7 mL/m² predicted adverse clinical outcome.

Outcomes of emergency or urgent mitral valve repair in patients with papillary muscle rupture and active infective endocarditis

BACKGROUND

Emergency or urgent surgery is often required in patients with papillary muscle rupture and active mitral valve infective endocarditis. The aim of this study was to analyze the outcomes of patients with active endocarditis who underwent emergency or urgent mitral valve repair.

METHODS

From 2005 to 2014, 154 ischemic mitral regurgitation patients and 41 infective endocarditis patients underwent mitral valve repair in our institution; 23 had emergency operations due to papillary muscle rupture, and 18 with active infective endocarditis underwent urgent surgery.

RESULTS

Cardiopulmonary bypass time (141.4 ± 43.3 versus 145.3 ± 46.5 min) and crossclamp time (77.7 ± 34.1 versus 79.2 ± 33.0 min) were similar in the papillary muscle rupture and elective ischemic mitral regurgitation subgroups, and major postoperative complications were comparable. Hospital mortality was 17.4% in the papillary muscle rupture subgroup and 8.4% in the elective ischemic mitral regurgitation subgroup. Cardiopulmonary bypass time (103.6 ± 37.0 versus 75.5 ± 20.8 min) and crossclamp time (61.7 ± 21.2 versus 45.3 ± 18.0 min) were significantly longer in infective endocarditis patients. There were no major complications or hospital deaths. Eight years postoperatively, overall survival was 94.4% and 86.5% in the papillary muscle rupture and elective ischemic mitral regurgitation subgroups, respectively (p = 0.730). Overall survival was 100% in both infective endocarditis subgroups.

CONCLUSION

The feasibility and effectiveness of emergency or urgent mitral valve repair in patients with papillary muscle rupture and active infective endocarditis are satisfactory. Early and mid-term outcomes are comparable to those of elective operations.

Early and long-term results of surgery for secondary mitral regurgitation with a damaged heart

BACKGROUND

Surgery for secondary mitral regurgitation is still controversial, especially when the left ventricle is damaged. The Mitra Clip has been shown to be safe and effective for certain patient groups but does not offer superior control of mitral regurgitation compared with the surgery. If performed safely, the surgery can provide greater benefits over the long-term. The objective of this study was to retrospectively investigate the early and long-term results of mitral valve surgery for secondary mitral valve regurgitation with a damaged, dilated left ventricle.

METHODS

Patients with ejection fraction <40% and left ventricular end-diastolic/systolic diameter >50/40 mm who underwent mitral valve surgery for secondary mitral regurgitation were investigated retrospectively.

RESULTS

The mean age of the 80 identified cases was 65.7 years, and 63 patients were male. Preoperative echocardiograms showed a mean ejection fraction of 25.2% and mean left ventricular diameters in diastole/systole of 64.5/56.9 mm, respectively. Mitral valve replacement was performed in 39 cases, and mitral valve plasty in 41 cases. The most common concomitant procedures were coronary artery bypass grafting and tricuspid valve surgery (41.3% each). Mitral regurgitation improved significantly from 3.5 to 0.83, and no operative or in-hospital deaths were encountered. Long-term results showed actual 1-, 3- and 5-year survival rates of 93.1%, 80.0%, and 64.7%, respectively (mean follow-up, 1264 days).

CONCLUSIONS

Early results of this study were good and long-term results were acceptable. Our results suggest that mitral valve surgery is feasible for secondary mitral valve regurgitation even in dilated, damaged hearts.

Outcome after percutaneous edge-to-edge mitral repair for functional and degenerative mitral regurgitation: a systematic review and meta-analysis

OBJECTIVES

Differences in terms of safety and efficacy of percutaneous edge-to-edge mitral repair between patients with functional and degenerative mitral regurgitation (MR) are not well established. We performed a systematic review and meta-analysis to clarify these differences.

METHODS

PubMed, EMBASE, Google scholar database and international meeting abstracts were searched for all studies about MitraClip. Studies with <25 patients or where 1-year results were not delineated between MR aetiology were excluded. This study is registered with PROSPERO.

RESULTS

A total of nine studies investigating the mid-term outcome of percutaneous edge-to-edge repair in patients with functional versus degenerative MR were included in the meta-analysis (n=2615). At 1 year, there were not significant differences among groups in terms of patients with MR grade≤2 (719/1304 vs 295/504; 58% vs 54%; risk ratio (RR) 1.12; 95% CI: 0.86 to 1.47; p=0.40), while there was a significantly lower rate of mitral valve re-intervention in patients with functional MR compared with those with degenerative MR (77/1770 vs 80/818; 4% vs 10%; RR 0.60; 95% CI: 0.38 to 0.97; p=0.04). One-year mortality rate was 16% (408/2498) and similar among groups (RR 1.26; 95% CI: 0.90 to 1.77; p=0.18). Functional MR group showed significantly higher percentage of patients in New York Heart Association class III/IV (234/1480 vs 49/583; 16% vs 8%; p<0.01) and re-hospitalisation for heart failure (137/605 vs 31/220; 23% vs 14%; p=0.03). No differences were found in terms of single leaflet device attachment (25/969 vs 20/464; 3% vs 4%; p=0.81) and device embolisation (no events reported in both groups) at 1 year.

CONCLUSIONS

This meta-analysis suggests that percutaneous edge-to-edge repair is likely to be an efficacious and safe option in patients with both functional and degenerative MR. Large, randomised studies are ongoing and awaited to fully assess the clinical impact of the procedure in these two different MR aetiologies.

Is valve repair preferable to valve replacement in ischaemic mitral regurgitation? A systematic review and meta-analysis

Ischaemic mitral regurgitation (MR) is associated with poor survival. The favoured surgical option remains debatable. Our aim was to perform a meta-analysis to compare the outcomes of mitral valve repair (MVRp) with replacement (MVR). A literature search was conducted in PubMed, Medline and Ovid using the terms 'ischaemic mitral regurgitation', 'repair' and 'replacement'. The primary outcome measure was 30-day survival. The secondary outcome measures were MR recurrence and reoperation. Out of 310 articles, 18 fulfilled the inclusion criteria. A total of 3978 patients were included: 2563 (64%) MVRp cases and 1415 (36%) MVR cases. Operative techniques included annuloplasty for MVRp and subvalvular apparatus-sparing MVR techniques. Thirty-day mortality was lower after MVRp compared with MVR [OR 0.42; (95% CI 0.33-0.54; P = 0.0001)]. There was no difference in long-term survival ranging 1-5 years (HR 0.85, 95% CI 0.65-1.12). Recurrence of MR was significantly higher in the MVRp group (OR 4.26, 95% CI 2.52-7.22), as was the rate of reoperation (OR 2.03, 95% CI 1.49-2.77). Although MVR for ischaemic MR has a higher 30-day mortality rate compared with MVRp, MVRp is associated with the higher rate of MR recurrence and the need for reoperation. MVR remains an attractive option for ischaemic MR.

MitraClip Therapy for Mitral Regurgitation: Primary Mitral Regurgitation

Primary mitral regurgitation (MR) owing to degenerative changes in the structural components of the mitral valve is a common acquired valvular pathology in the elderly. Surgical correction with mitral valve repair (MVRe) or replacement (MVR) is the mainstay of therapy. A significant proportion of patients are ineligible for MVRe/MVR owing to prohibitive surgical risk from advanced age, poor ventricular function, or associated comorbidities. Percutaneous mitral valve repair techniques have been developed to fill this void. The edge-to-edge MitraClip has accrued the largest human experience. This paper reviews the available literature on the MitraClip device for treatment of primary MR.

Geriatric cardiac surgery: chronology vs. biology

Cardiac surgery is increasingly performed in elderly patients, and whilst the incidence of common risk factors associated with poorer outcome increases with age, recent studies suggest that outcomes in this population may be better than is widely appreciated. As such, in this review we have examined the current evidence for common cardiac surgical procedures in patients aged over 70 years. Coronary artery bypass grafting (CABG) in the elderly has similar early safety to percutaneous intervention, though repeat revascularisation is lower. Totally avoiding instrumentation of the ascending aorta with off-pump techniques may also reduce the incidence of neurological injury. Aortic valve replacement (AVR) significantly improves quality of life and provides excellent short- and long-term outcomes. Combined AVR and CABG carries higher risk but late survival is still excellent. Mini-sternotomy AVR in the elderly can provide comparable survival to full-sternotomy AVR. More accurate risk stratification systems are needed to appropriately select patients for transcatheter aortic valve implantation. Mitral valve repair is superior to replacement in the elderly, although choosing the most effective method is important for achieving maximal quality of life. Minimally-invasive mitral valve surgery in the elderly has similar postoperative outcomes to sternotomy-based surgery, but reduces hospital length of stay and return to activity. In operative candidates, surgical repair is superior to percutaneous repair. Current evidence indicates that advanced age alone is not a predictor of mortality or morbidity in cardiac surgery. Thus surgery should not be overlooked or denied to the elderly solely on the basis of their "chronological age", without considering the patient's true "biological age".

Devices for mitral valve repair

The natural history of severe mitral regurgitation (MR) is unfavorable, leading to left ventricular failure, atrial fibrillation, stroke, and death. Many patients affected by severe regurgitation (MR) do not currently undergo surgery, mainly due to the perceived risk of the procedure (old age, impaired left ventricular function, and comorbidities). Mitral transcatheter interventions carry the hope of minimizing risks while preserving clinical efficacy of surgical repair, as an alternative to conventional treatment. Multiple technologies and diversified approaches are under development with the purpose of treating MR in less invasive ways. They can be categorized based on the anatomical and patho-physiological addressed target. Among them, MitraClip (Abbott Vascular, Inc., Menlo Park, California) has emerged as a clinically safe and effective method for percutaneous mitral valve repair in patients either with degenerative and functional regurgitation. This device mimics the surgical edge-to-edge repair initially described by Alfieri in the early 1990s. Other repair technologies include percutaneous direct and indirect annuloplasty, neochordae implantation, and left ventricular reshaping. They are still in early phase clinical trials or preclinical studies. The combination of different repair techniques is likely to be required to achieve good long-lasting results. In the future, novel devices, improved knowledge, more efficient imaging, and transcatheter mitral prosthetic valve implantation may expand the indications to those patients currently not treated, as well as improve the results both in terms of early efficacy and long-term durability. These treatments are currently reserved to high-risk and inoperable patients, and their application requires an integrated Heart-Team approach. They represent the natural evolution of surgery and promise to expand treatment options and improve patients' outcomes in the near future.

Echocardiographic Predictors of Adverse Short-term Outcomes after Heart Surgery in Patients with Mitral Regurgitation and Pulmonary Hypertension

<p><b>Background:</b> Pulmonary hypertension (PH) is a frequent occurrence and a negative prognostic indicator in patients with mitral regurgitation. Preoperative PH causes higher early and late mortality rates after heart surgery, adverse cardiac events, and postoperative systolic dysfunction in the left ventricle (LV).</p><p><b>Methods:</b> The research consisted of a retrospective study of a group of 171 consecutive patients with mitral regurgitation and preoperative PH who had undergone mitral valve surgery between January 2008 and October 2011. The PH diagnosis was based on echocardiographic evidence (systolic pulmonary artery pressure [sPAP] >35 mm Hg). The echocardiographic examination included assessment of the following: LV volume, LV ejection fraction (LVEF), sPAP, right ventricular end-diastolic diameter, right atrium area indexed to the body surface area, the ratio of the pulmonary acceleration time to the pulmonary ejection time (PAT/PET), tricuspid annular plane systolic excursion (TAPSE), determination of the severity of the associated tricuspid regurgitation, and presence of pericardial fluid. Surgical procedures consisted of mitral valve repair in 55% of the cases and mitral valve replacement in the remaining 45%. Concomitant coronary artery bypass grafting (CABG) surgery was carried out in 52 patients (30.41%), and De Vega tricuspid annuloplasty was performed in 29 patients (16.95%). The primary end point was perioperative mortality. The secondary end points included the following: pericardial, pleural, hepatic, or renal complications; the need for a new surgical procedure; postoperative mechanical ventilation >24 hours; length of stay in the intensive care unit; duration of postoperative inotropic support; need for an intra-aortic balloon pump; and need for pulmonary vasodilator drugs.</p><p><b>Results:</b> The mortality rate was 2.34%. In the univariate analysis, the clinical and echocardiographic parameters associated with mortality were preoperative New York Heart Association (NYHA) class IV, the PAT/PET ratio, TAPSE, the indexed area of the right atrium, and concomitant CABG surgery. In the multivariate analysis, the indexed area of the right atrium and concomitant CABG surgery remained statistically significant. The multivariate analysis also showed the indexed area of the right atrium, LVEF, presence of pericardial fluid, preoperative NYHA class, and concomitant CABG surgery as statistically significant for the secondary end point. The receiver operating characteristic (ROC) curves identified an sPAP value >65 mm Hg to have the highest specificity and sensitivity for the risk of perioperative death in mitral regurgitation patients (area under the ROC curve [AUC], 0.782; <i>P</i> < .001) and identified an sPAP value of 60 mm Hg as the secondary end point (AUC, 0.82; <i>P</i> < .001). Severe PH (sPAP >60 mm Hg) is associated with a significant increase in the mortality rate; a longer stay in the intensive care unit; a mechanical ventilation duration >24 hours; lengthy inotropic support; renal, hepatic, and pericardial complications; and a need for endothelin receptor antagonists, phosphodiesterase type 5 inhibitors, and/or prostanoids, both in the general group and in patients with preserved systolic functioning of the left ventricle.</p><p><b>Conclusions:</b> PH is a strong short-term negative prognostic factor for patients with mitral regurgitation. The surgical procedure should be performed in the early stages of PH. Echocardiographic examination has useful, simple, and reproducible tools for classifying operative risks. An ischemic etiology and a need for concomitant CABG surgery are additional risk factors for patients with mitral regurgitation and PH.</p>

Minimally invasive video-assisted cardiac surgery: operative techniques, application fields and clinical outcomes

Minimally invasive video-assisted surgery through a right minithoracotomy has become the standard surgical approach for several cardiac diseases at many major centers worldwide. In this article we review the existing literature on the subject and describe different operative techniques, application fields and clinical outcomes.

Outcomes of coronary artery bypass grafting and reduction annuloplasty for functional ischemic mitral regurgitation: a prospective multicenter study (Randomized Evaluation of a Surgical Treatment for Off-Pump Repair of the Mitral Valve)

OBJECTIVE

Functional ischemic mitral regurgitation is a complication of ventricular remodeling; standard therapy is reduction annuloplasty and coronary artery bypass grafting. Unfortunately, outcomes are retrospective and contradictory. We report a multicenter study that documents the outcomes of reduction annuloplasty for functional ischemic mitral regurgitation.

METHODS

Twenty-one centers randomized 75 patients to the coronary artery bypass grafting + reduction annuloplasty subgroup that was the control arm of the Randomized Evaluation of a Surgical Treatment for Off-pump Repair of the Mitral Valve trial. Entry criteria included patients requiring revascularization, patients with severe or symptomatic moderate functional ischemic mitral regurgitation, an ejection fraction 25% or greater, a left ventricular end-diastolic dimension 7.0 cm or less, and more than 30 days since acute myocardial infarction. All echocardiograms were independently scored by a core laboratory. Reduction annuloplasty was achieved by device annuloplasty. Two patients underwent immediate intraoperative conversion to a valve replacement because reduction annuloplasty was unable to correct mitral regurgitation; as-treated results are presented.

RESULTS

Thirty-day mortality was 4.1% (3/73). Patients received an average of 2.8 bypass grafts. Mean follow-up was 24.6 months. Mitral regurgitation was reduced from 2.6 ± 0.8 preoperatively to 0.3 ± 0.6 at 2 years. Freedom from death or valve reoperation was 78% ± 5% at 2 years. There was significant improvement in ejection fraction and New York Heart Association class with reduction of left ventricular end-diastolic dimension. Cox regression analyses suggested that increasing age (P = .001; hazard ratio, 1.16 per year; 95% confidence interval, 1.06-1.26) and renal disease (P = .018; hazard ratio, 3.48; 95% confidence interval, 1.25-9.72) were associated with decreased survival.

CONCLUSIONS

Coronary artery bypass grafting + reduction annuloplasty for functional ischemic mitral regurgitation predictably reduces mitral regurgitation and relieves symptoms. This treatment of moderate to severe mitral regurgitation is associated with improved indices of ventricular function, improved New York Heart Association class, and excellent freedom from recurrent mitral insufficiency. Although long-term prognosis remains guarded, this multicenter study delineates the intermediate-term benefits of such an approach.

A propensity score-adjusted retrospective comparison of early and mid-term results of mitral valve repair versus replacement in octogenarians

AIMS

Feasibility and efficacy of mitral repair in the elderly remain controversial. This study aims to compare outcomes of mitral repair and replacement in octogenarians.

METHODS AND RESULTS

We compared the outcomes of 322 consecutive octogenarian patients (mean age 82.6 ± 2.2 years) who underwent mitral repair (n = 227, 70%) or replacement (n = 95, 30%) at Mount Sinai Medical Center and Leipzig Herzzentrum between 1998 and 2008 using propensity score adjustment and univariate and multivariate analyses. Patients undergoing aortic valve replacement were excluded. Coronary bypass was performed in 47.5% (n = 153), and 31.1% (n = 100) required tricuspid repair. Propensity score adjustment yielded comparable groups. Thirty-day mortality in patients undergoing primary elective mitral repair for degenerative disease was 5.1% (2/39). Overall 90-day mortality was 18.9% (43/227) for repair compared with 31.6% (30/95) for replacement (P = 0.014). Pre-discharge echocardiography revealed less than moderate residual regurgitation in 99% of patients (231/232). Adjusted 1-, 3-, and 5-year survival for patients undergoing mitral repair was 71 ± 3, 61 ± 4, and 59 ± 4%, respectively, compared with 56 ± 5, 50 ± 6, and 45 ± 6% for patients undergoing mitral replacement (P = 0.046). Multivariate analysis demonstrated emergency surgery, previous myocardial infarction, concomitant coronary artery bypass surgery, and mitral replacement to be strong independent predictors of early mortality; mitral valve replacement was an independent predictor of reduced survival in degenerative patients.

CONCLUSION

Elective mitral repair can be performed with low operative mortality and good long-term outcomes in selected octogenarians with degenerative mitral disease, and is associated with better long-term survival than mitral replacement. The survival benefit associated with surgery for non-degenerative disease is more questionable.

Long-term influence of mild or moderate ischemic mitral regurgitation after off-pump coronary artery bypass surgery

BACKGROUND

The issue of mild to moderate ischemic mitral regurgitation (IMR) is controversial after conventional surgery, and has not been specifically studied after off-pump coronary artery bypass graft (OPCAB) surgery.

OBJECTIVE

To review the influence of mild or moderate IMR on longterm survival and recurrent cardiac events after OPCAB surgery.

METHODS

A total of 1000 consecutive and systematic OPCAB patients who underwent operations between September 1996 and March 2004 were prospectively followed. Sixty-seven patients (6.7%) had mild to moderate IMR at the time of surgery. Operative mortality, actuarial survival and major adverse cardiac event-free survival were studied to assess the effect of IMR.

RESULTS

The mean (+/- SD) follow-up period was 66+/-22 months and was completed in 97% of the cohort. IMR patients were older (P<0.001), and had lower ejection fractions (P<0.001) and more comorbidities. More female patients presented with IMR (P=0.002). Operative mortality (P=0.25) and prevalence of perioperative myocardial infarction (P=0.25) were comparable for both groups. Eight-year survival was decreased in IMR patients (P<0.001), but after adjusting for risk factors in the Cox regression model, mild to moderate IMR was not found to be a significant risk factor of long-term mortality (P=0.42). Major adverse cardiac event-free survival at eight years was significantly lower in IMR patients (P<0.001) and, more specifically, in patients with 2+ IMR. After adjusting for risk factors, IMR remained a significant cause of poor outcome (hazard ratio 2.09), especially for recurrent congestive heart failure and myocardial infarction.

CONCLUSIONS

OPCAB patients with preoperative mild or moderate IMR had a higher prevalence of preoperative risk factors than those without IMR. They had comparable perioperative mortality and morbidity but, over the long term, were found to be at risk for recurrent cardiac events.

Percutaneous mitral valve repair: the beginning of the end or the end of the beginning?

The new percutaneous mitral valve repair techniques are at an early stage. Preliminary series show that they are feasible; however, they need to be further evaluated in comparison with contemporary treatment to accurately assess their efficiency. Potential applications may benefit high-risk patients after thorough evaluation.

Mitral repair versus replacement for ischemic mitral regurgitation: comparison of short-term and long-term survival

BACKGROUND

When compared to mitral valve replacement (MVR), mitral valve repair (MVRp) is associated with better survival in patients with organic mitral regurgitation (MR). However, there is an important controversy about the type of surgical treatment that should be used in patients with ischemic MR. The objective of this study was to compare the postoperative outcome of MVRp versus MVR in patients with ischemic MR.

METHODS AND RESULTS

Preoperative and operative data of 370 patients with ischemic MR who underwent mitral valve surgery were prospectively collected and retrospectively analyzed. MVRp was performed in 50% of patients (n=186) and MVR in 50% (n=184). Although operative mortality was significantly lower after MVRp compared to MVR (9.7% versus 17.4%; P=0.03), overall 6-year survival was not statistically different between procedures (73+/-4% versus 67+/-4%; P=0.17). After adjusting for other risk factors and propensity score, the type of procedure (MVRp versus MVR) did not come out as an independent predictor of either operative (OR, 1.5; 95% CI, 0.7-2.9; P=0.34) or overall mortality (HR, 1.2; 95% CI, 0.7-1.9; P=0.52).

CONCLUSIONS

As opposed to what has been reported in patients with organic MR, the results of this study suggest that MVRp is not superior to MVR with regard to operative and overall mortality in patients with ischemic MR. These findings provide support for the realization of a randomized trial comparing these 2 treatment modalities.

Minimally invasive mitral valve surgery: a systematic review and meta-analysis

The mitral valve has been traditionally approached through a median sternotomy. However, significant advances in surgical optics, instrumentation, tissue telemanipulation, and perfusion technology have allowed for mitral valve surgery to be performed using progressively smaller incisions including the minithoracotomy and hemisternotomy. Due to reports of excellent results, minimally invasive mitral valve surgery has become a standard of care at certain specialized centers worldwide. This meta-analysis quantifies the effects of minimally invasive mitral valve surgery on morbidity and mortality compared with conventional mitral surgery and demonstrates equivalent perioperative mortality (1641 patients, odds ratio (OR) 0.46, 95% confidence interval 0.15-1.42, p=0.18), reduced need for reoperation for bleeding (1553 patients, OR 0.56, 95% CI 0.35-0.90, p=0.02) and a trend towards shorter hospital stays (350 patients, weighted mean difference (WMD) -0.73, 95% CI -1.52 to 0.05, p=0.07). These benefits were evident despite longer cardiopulmonary bypass (WMD 25.81, 95% CI 13.13-38.50, p<0.0001) and cross-clamp times (WMD 20.91, 95% CI 8.79-33.04, p=0.0007) in the minimally invasive group. Case-control studies show consistently less pain and faster recovery compared to those having a conventional approach. Data for minimally invasive mitral valve surgery after previous cardiac surgery are limited but consistently demonstrate reduced blood loss, fewer transfusions and faster recovery compared to reoperative sternotomy. Long-term follow-up data from multiple cohort studies are also examined revealing equivalent survival and freedom from reoperation. Thus, current clinical data suggest that minimally invasive mitral valve surgery is a safe and a durable alternative to a conventional approach and is associated with less morbidity.

Etiology and short-term prognosis of severe mitral regurgitation

PURPOSE

To describe the etiology and to document the course of severe mitral regurgitation (MR).

METHODS

Prospective registry of 272 patients diagnosed with chronic severe MR in an echocardiographic study.

RESULTS

Mean age was 70.2 +/- 13.8 years and 143 patients were women (53%). The most frequent causes of regurgitation were rheumatic disease (72 patients; 26%), ischemic etiology (58; 21%), valve prolapse (57; 21%), and dilated cardiomyopathy (49; 18%). A total of 43 patients (16%) died during follow-up (mean 0.9 +/- 0.3 years, total 2,785 patient-months): 30 from cardiac causes, 9 from non-cardiac causes, and 4 from unknown causes. Actuarial transplant-free survival was 87% at 6 months, and 81% at 1 year. Renal disease, previous stroke, ischemic etiology, and poor left ventricular ejection fraction were independent predictors of mortality.

CONCLUSIONS

Rheumatic disease is still the main cause of severe MR in Spain. Patients with severe MR have advanced age and present poor short-term prognosis.

Intraoperative TEE Assessment During Mitral Valve Repair for Degenerative and Ischemic Mitral Valve Regurgitation

Intraoperative assessment of the mitral valve (MV) in patients undergoing repair for MV regurgitation is a valuable support for the cardiac surgical team; results can be favored by adequate assessment tailored to the main condition affecting the MV. This article will review current available data for assessment of the MV in degenerative and ischemic mitral regurgitation.

A Change in Perspective: Results for Ischemic Mitral Valve Repair Are Similar to Mitral Valve Repair for Degenerative Disease

BACKGROUND

Although the benefits of mitral valve repair for degenerative disease are well established, many consider surgery for functional ischemic mitral regurgitation (MR) less amenable to operative treatment. We hypothesized that mitral valve repair for ischemic MR results in outcomes similar to those for mitral valve repair for degenerative MR.

METHODS

Retrospective review of nonemergent mitral valve repairs for an 8-year period revealed 105 patients with functional ischemic MR, of whom 39 were treated for severe tethering (ischemic group), and 245 patients with degenerative MR (degenerative group).

RESULTS

Patients in the ischemic group had more comorbidities (p < 0.01) and worse preoperative left ventricular dysfunction (ejection fraction < or = 0.29) compared with patients in the degenerative group; (ischemic, 37.1% [39 of 105] versus degenerative, 2.0% [5 of 245]; p < 0.01). Immediate postrepair transesophageal echocardiogram revealed a 0 to 1+ MR in all patients in both groups (not significant). The hospital mortality rate was 1.9% (2 of 105) in the ischemic group and 1.2% (3 of 245) in the degenerative group (p = 1.00). The 5-year survival rate was 83.9% in the ischemic group and 94.3% in the degenerative group (p < 0.01). Five-year freedom from reoperation for recurrent MR was 100% and 97.5% in the ischemic and degenerative groups, respectively (p = 0.14). Postoperative renal failure and stroke rates were similar between both groups (not significant). The incidence of moderate or greater MR after more than 1 year of follow-up was similar between groups (not significant).

CONCLUSIONS

Despite the multiple comorbidities that afflict patients with ischemic MR, mitral valve repair for ischemic and degenerative disease produces comparable and satisfactory outcomes. An aggressive approach to repair of functional ischemic MR, including treatment of tethering, leads to durable results.

A Simplified Approach to Degenerative Disease: Triangular Resections of the Mitral Valve

BACKGROUND

Only 40% of patients with mitral valve (MV) regurgitation undergo operative repair rather than replacement. Quadrangular resection combined with ring annuloplasty has been the most common method of repair for degenerative posterior leaflet disease. Techniques such as sliding annuloplasty and artificial chord usage have increased the complexity of repair. These techniques have been perceived to be difficult and have possibly reduced the incidence of MV repair. We present our experience with a simplified approach to MV repair utilizing a triangular resection and larger rings.

METHODS

Retrospective review of all MV repairs over a 7-year period (1999 to 2006) revealed 154 patients who underwent triangular resection for degenerative disease. Patients who underwent ring annuloplasty without leaflet resection and patients who had artificial chords or quadrangular resections were excluded.

RESULTS

Of 154 patients who underwent triangular resection, isolated posterior leaflet resection was performed on 130 patients. Isolated anterior and combined anterior and posterior leaflet triangular resections were performed on 16 and 8 patients, respectively. Thirty-day postoperative mortality was 0%. Five-year freedom from reoperation for recurrent mitral regurgitation was 99.0%. No patients who had intended leaflet resection were converted to MV replacement. Intraoperative transesophageal echocardiogram revealed trace to 1+ mitral regurgitation. Mild systolic anterior motion was noted in 7.1% of cases initially, but resolved with volume loading in all.

CONCLUSIONS

Triangular leaflet resection of the mitral valve produces durable results and can be safely and efficiently performed with minimal morbidity and mortality. This technique should allow increased utilization of MV repair for degenerative disease.

Impact of Moderate Functional Mitral Insufficiency in Patients Undergoing Surgical Revascularization

BACKGROUND

Mild and moderate functional ischemic mitral insufficiency present at the time of surgical revascularization present clinical uncertainty. It is unclear whether the relatively poor outcomes in this cohort are dependent on valvular function or related to left ventricular dysfunction. The purpose of this study was to examine the early and late outcomes in patients with less-than-severe functional ischemic mitral insufficiency at the time of isolated coronary artery bypass grafting (CABG).

METHODS AND RESULTS

From 1996 through 2004, 2242 consecutive patients undergoing isolated CABG were identified as having none to moderate mitral regurgitation (MR) and no valve leaflet pathology. All of the patients at this single institution routinely had an intraoperative transesophageal echocardiography, prospectively quantified MR, and ejection fraction (EF). The New York State Cardiac Surgery Reporting System infrastructure was used to prospectively collect in-hospital patient variables and outcomes. Social Security Death Benefit Index was used to determine long-term survival. Odds ratio and significance (P value) are presented for each determined risk factor. There were 841 patients (37.5%) with no MR, 1137 (50.7%) with mild MR, and 264 (11.8%) with moderate MR. The patients with moderate MR were more likely to be older, female, and have more renal disease, previous MI, congestive heart failure, previous cardiac surgery, and lower EFs. Hospital mortality was independently and significantly associated with renal disease, decreasing EF, increasing age, previous cardiac operation, and cerebral vascular disease. Multivariable analysis revealed decreased survival with increasing age, previous operation, congestive heart failure, diabetes, nonelective operation, decreasing EF, and the presence of moderate MR (expbeta = 1.49; P=0.007) and mild MR (expbeta = 1.34; P=0.033).

CONCLUSIONS

Independent of ventricular function, mild and moderate functional mitral insufficiency are associated with significantly decreased survival in patients undergoing CABG. Whether correction of moderate functional MR at the time of CABG improves outcome still needs to be determined.

Mitral valve repair or replacement in elderly people

PURPOSE OF REVIEW

Much has been published so far to describe and praise the benefits of mitral valve repair, and to compare it with valve replacement. Now, with mitral valve surgery in elderly people gaining greater acceptance worldwide, repair or replacement remains a controversial issue. This is especially true in the ageing population, in whom many of the complications associated with a mechanical valve can be avoided by using a bioprosthesis. This review will try to assess the latest views in the field and come up with possible answers to this ongoing question.

RECENT FINDINGS

The causes of mitral regurgitation in this age group are separately reviewed and discussed in the light of our better understanding of the pathophysiology of the disease. Mitral surgery is recommended when the effective regurgitant orifice reaches 40 mm. Repair in degenerative disease seems to be feasible, with good long-term results. In chronic ischaemic regurgitation, the concept of a tethered 'normal valve' is changing. The 'poor' ventricle may be able to withstand surgery as long as the subvalvular apparatus is preserved; on the other hand, repair and replacement seem to have the same survival advantage in high-risk patients.

SUMMARY

Mitral valve surgery is well tolerated in elderly people. Early intervention leads inevitably to better outcome. The majority of valvular disorders in this age group are amenable to repair, with good reproducible results. Replacement with a bioprosthesis remains a viable option for complex regurgitant jets.