Mitral valve surgery in patients with severe left ventricular dysfunction

The future of group 2 pulmonary hypertension: Exploring clinical trials and therapeutic targets

Pulmonary hypertension due to left heart disease (PH-LHD) or group 2 PH is the most common and lethal form of PH, occurring secondary to left ventricular systolic or diastolic heart failure (HF), left-sided valvular diseases, and congenital abnormalities. It is subdivided into isolated postcapillary PH (IpcPH) and combined pre- and post-capillary PH (CpcPH), with the latter sharing many similarities with group 1 PH. CpcPH is associated with worse outcomes and increased morbidity and mortality when compared to IpcPH. Although IpcPH can be improved by treatment of the underlying LHD, CpcPH is an incurable disease for which no specific treatment exists, likely due to the lack of understanding of its underlying mechanisms. Furthermore, drugs approved for PAH are not recommended for group 2 PH, as they are either ineffective or even deleterious. With this major unmet medical need, a better understanding of mechanisms and the identification of effective treatment strategies for this deadly condition are urgently needed. This review presents relevant background of the molecular mechanisms underlying PH-LHD that could translate into innovative therapeutic targets and explores novel targets currently being evaluated in clinical trials.

Contemporary contribution of cardiac surgery for the treatment of cardiomyopathies and pericardial diseases

Cardiomyopathy refers to a spectrum of heterogeneous myocardial disorders characterized by morphological and structural alterations leading eventually to heart failure, by affecting cardiac filling and/or the cardiac systolic function. Heart transplantation is currently the gold standard surgical treatment for patients with heart failure, with a median survival in adults of 12 years according to international registries. However, the limited available donor pool does not allow its extensive employment. For this reason, mechanical circulatory supports are increasingly used, and in the short term are becoming as possible alternatives to heart transplantation, owing to improved technologies and increased biocompatibility. However, long-term outcomes of mechanical assist devices are still burdened with a high rate of adverse events. Conventional surgical treatments could be still considered as alternatives to heart replacement treatment when tailored both on patient clinical conditions and etiology of cardiac diseases. In particular, among patients affected by ischemic cardiomyopathy, coronary artery bypass grafting has proven to improve survival when associated to optimal medical treatment, and surgical ventricular restoration might be considered as a valid treatment in particular cases. Correction of functional mitral valve regurgitation by mitral annuloplasty, which aims to restore left ventricular geometry, has not demonstrated unambiguous results, and outcomes of this procedure are still controversial. Pericardial pathology becomes of surgical interest when it is responsible for a reduced filling capacity of the heart chambers, which can develop acutely (cardiac tamponade) or chronically (as in the case of constrictive pericarditis). This review focuses on the different surgical approaches that could be adopted to treat patients with heart failure and pericardial diseases.

Revisiting the Role of Guideline-Directed Medical Therapy for Patients with Heart Failure and Severe Functional Mitral Regurgitation

Patients with heart failure often have mitral regurgitation, which can generate a vicious cycle. Medical therapy remains the cornerstone of their treatment in this setting. This review revisits the role of medical therapy and its optimization for severe functional mitral regurgitation in the contemporary era.

Ischemic Mitral Regurgitation: A Multifaceted Syndrome with Evolving Therapies

Dysfunction of the left ventricle (LV) with impaired contractility following chronic ischemia or acute myocardial infarction (AMI) is the main cause of ischemic mitral regurgitation (IMR), leading to moderate and moderate-to-severe mitral regurgitation (MR). The site of AMI exerts a specific influence determining different patterns of adverse LV remodeling. In general, inferior-posterior AMI is more frequently associated with regional structural changes than the anterolateral one, which is associated with global adverse LV remodeling, ultimately leading to different phenotypes of IMR. In this narrative review, starting from the aforementioned categorization, we proceed to describe current knowledge regarding surgical approaches in the management of IMR.

Evaluation of β-blocker therapy for long-term outcomes in patients with low ejection fraction after cardiac surgery

Background

Preoperative low left ventricular ejection fraction (LVEF) has been reported as an independent risk factor for in-hospital mortality. However, there were few studies evaluating the long-term mortality in these patients. We, therefore, conducted this study to investigate long-term outcomes of surgery on patients with LVEF≤35% undergoing a broad range of cardiac procedures.

Methods

We performed a retrospective cohort study in 510 patients from January 1, 2007 to September 1, 2019. These patients were divided into survival group (n = 386) and non-survival group (n = 124). The multivariate Cox analysis was used to estimate the risk factors for survival. In Cox analysis, β-blockers were indicated to be associated with long-term mortality. To further address bias, we derived a propensity score predicting the function of β-blockers on survival, and matched 52 cases to 52 controls with similar risk profiles.

Results

Patients were followed for a median period of 24 months (interquartile range: 11–44 months). Multivariate Cox regression analysis indicated that the non-survival group had higher weight, higher EuroSCORE, more smoking patients, longer time of cardiopulmonary bypass (CPB), more intra-aortic balloon pump (IABP) use, and more patients who always used β-blocker (HR: 2.056, 95%CI:1.236–3.420, P = 0.005) compared with survival group. After propensity matching, the group which always used β-blocker showed higher rate of all-cause death compare with the control group (61.54% vs 80.77%, P = 0.030).

Conclusions

The risk factors for long-term survival were weight, EuroSCORE, smoking, CPB, IABP, always used β-blockers in patients with LVEF≤35%. The discharge prescription of β-blocker should be cautiously administrated in those patients.

Feasibility and limitations of mitral valve repair, with or without left ventricular reconstruction in non-ischemic dilated cardiomyopathy

BACKGROUND

Although non-transplant surgical interventions for non-ischemic dilated cardiomyopathy (NIDCM) are relatively effective, their feasibility and limitations have not been fully elucidated. The aim of this study was to define the feasibility and limitations of mitral valve repair, with or without surgical ventricular reconstruction for patients with NIDCM in terms of postoperative low cardiac output syndrome (LOS).

METHODS

Twenty non-transplant candidates (aged 57±13 years) with NIDCM and significant mitral regurgitation had undergone mitral valve repair combined with submitral procedures. Using a 72-mL plastic ellipsoidal sizer, left ventricular reconstruction was performed concomitantly in 14/20 (70%) patients with extremely large ventricles. Total stroke volume, deceleration time of early trans-mitral flow wave, and the slope (Mw) in the preload recruitable stroke-work relationship were assessed using transthoracic echocardiography. LOS was defined as in-hospital death due to heart failure or a cardiac index less than 2.2L/min/m² before discharge.

RESULTS

There were three in-hospital deaths and four patients with postoperative cardiac index less than 2.2L/min/m² [n=7 (35%), LOS group]. Preoperative total stroke volume, deceleration time, and the Mw were significantly lower in the LOS group compared to those in the non-LOS group; the predicted cut-off values for LOS were 84mL/beat (p=0.008), 133ms (p=0.015), and 45ergcm^-3×10³ (p=0.036), respectively. Preoperative left ventricular ejection fraction and ventricular size could not predict postoperative LOS. The one-year survival rate was 0% in the LOS group and 84% in the non-LOS group (p<0.001).

CONCLUSIONS

Mitral valve repair, with or without left ventricular reconstruction, could be contraindicated for NIDCM patients with low total stroke volume, deceleration time, and Mw in terms of high postoperative incidence of LOS. For high-risk patients, other therapeutic strategies might be necessary.

High-risk cardiac surgery as an alternative to transplant or mechanical support in patients with end-stage heart failure

OBJECTIVE

Although the results of cardiac surgery in patients with poor left ventricular function have been widely published, the outcomes in patients with end-stage heart failure who meet criteria for advanced therapies are not well investigated. As access to transplantation and ventricular assist device therapy remains limited, we explored the possibility of conventional surgery as an alternative option for highly selected patients with end-stage heart failure.

METHODS

We identified patients with left ventricular ejection fraction <20% and VO₂ max <14 mL/min/m², who were initially referred for advanced therapies but were instead offered a conventional procedure from 2002 to 2012. We examined the short- and midterm outcomes and compared survival with that after our advanced therapies in the same era.

RESULTS

A total of 133 patients were identified; 68 were deemed to be transplant-eligible, whereas 65 were transplant-ineligible. Seventy-nine percent were in New York Heart Association class III/IV. In-hospital mortality was 12%. Actuarial survival at 5 and 10 years was 72% ± 4% and 39% ± 8%, respectively. Nonischemic etiology was identified as a predictor of late mortality. In the propensity-adjusted model, our transplant-eligible patients had comparable long-term survival to our transplantation patients (HR 1.48 [95% confidence interval, 0.66-3.2], P = .34), whereas the survival in our transplant-ineligible subset was comparable to the survival after our left ventricular assist device therapy (HR 0.49 [95% confidence interval, 0.16-1.50], P = .21).

CONCLUSIONS

Despite high perioperative risk, the midterm survival after conventional surgery in patients eligible for advanced therapies seems to be acceptable and may be an alternative option for highly selected patients with end-stage heart failure.

Functional Mitral Regurgitation: Appraising the Evidence Behind Recommended Treatment Strategies

Functional mitral regurgitation (MR) is the most common type of MR encountered in clinical practice. Because the disease arises from the ventricular aspect of the mitral valve apparatus, treatment therapies are less defined and outcomes are poor. In this review, the state of evidence for medical and surgical therapy in functional MR is appraised. Future directions for research in this area are also defined.

Valve Repair: A "Bridge" to Heart Transplant

Cardiac transplants are limited because of a deficiency of donor organs. Most recipients with severe chronic heart failure are on a waiting list. Therefore, palliative surgical treatment of chronic heart failure is widely used. We report a case of successful application of palliative surgical approach for a patient with decompensated heart failure.

Percutaneous Repair of Mitral Regurgitation with the MitraClip: Regional Experience and Clinical Indications

The MitraClip is the first-in-class percutaneous therapy for mitral regurgitation. It is delivered from the femoral vein and can be used for degenerative or functional mitral regurgitation. In Singapore, the device was first approved for use in 2011. This review describes the device and discusses the data supporting its use and the regional experience to date. The MitraClip, given the early experience, should only be used after consideration by Heart Teams and only in appropriately selected patients.

Management of severe ischemic cardiomyopathy: left ventricular assist device as destination therapy versus conventional bypass and mitral valve surgery

OBJECTIVES

Patients with severe ischemic cardiomyopathy (left ventricular ejection fraction <25%) and severe ischemic mitral regurgitation have a poor survival with medical therapy alone. Left ventricular assist device as destination therapy is reserved for patients who are too high risk for conventional surgery. We evaluated our outcomes with conventional surgery within this population and the comparative effectiveness of these 2 therapies.

METHODS

We identified patients who underwent conventional surgery or left ventricular assist device as destination therapy for severe ischemic cardiomyopathy (left ventricular ejection fraction <25%) and severe mitral regurgitation. The era for conventional surgery spanned from 1993 to 2009 and from 2007 to 2011 for left ventricular assist device as destination therapy. We compared baseline patient characteristics and outcomes in terms of end-organ function and survival.

RESULTS

A total of 88 patients were identified; 55 patients underwent conventional surgery (63%), and 33 patients (37%) received a left ventricular assist device as destination therapy. Patients who received left ventricular assist device as destination therapy had the increased prevalence of renal failure, inotrope dependency, and intra-aortic balloon support. Patients undergoing conventional surgery required longer ventilatory support, and patients receiving a left ventricular assist device required more reoperation for bleeding. Mortality rates were similar between the 2 groups at 30 days (7% in the conventional surgery group vs 3% in the left ventricular assist device as destination therapy group, P = .65) and at 1 year (22% in the conventional surgery group vs 15% in the left ventricular assist device as destination therapy group, P = .58). There was a trend toward improved survival in patients receiving a left ventricular assist device compared with the propensity-matched groups at 1 year (94% vs 71%, P = .171).

CONCLUSIONS

The operative mortality and early survival after conventional surgery seem to be acceptable. For inoperable or prohibitive-risk patients, left ventricular assist device as destination therapy can be offered with similar outcomes.

Outcomes of minimally invasive mitral valve surgery in patients with an ejection fraction of 35% or less

OBJECTIVE

We evaluated the outcomes of minimally invasive mitral valve surgery via a right anterior thoracotomy approach in patients with isolated severe mitral regurgitation and severely reduced left ventricular systolic function.

METHODS

We retrospectively reviewed all minimally invasive mitral valve surgeries for mitral regurgitation in patients with an ejection fraction of 35% or less performed at our institution between December 2008 and June 2011. The operative times, lengths of stay, postoperative complications, and mortality were analyzed.

RESULTS

We identified a total of 71 patients with severe mitral regurgitation and an ejection fraction of 35% or less who underwent minimally invasive mitral valve surgery. The mean ± SD age was 67 ± 10 years, and 44 of the patients were men (62%). The mean ± SD left ventricular ejection fraction was 27% ± 6%, and 28 patients (39%) had previous heart surgery. The median aortic cross-clamp and cardiopulmonary bypass times were 62 [interquartile range (IQR), 50-80) and 98 minutes (IQR, 92-124), respectively. There was no mitral regurgitation noted in any patient on postoperative transesophageal echocardiogram. The median intensive care unit length of stay was 51 hours (IQR, 42-86), and the median postoperative length of stay was 6 days (IQR, 5-9).

CONCLUSIONS

Minimally invasive mitral valve surgery for severe functional mitral regurgitation in patients with severe left ventricular dysfunction can be performed with a low morbidity and mortality.

Heart valve disease

Heart valve disease is often characterized by a prolonged asymptomatic period that lasts for years and presents primary care physicians with an opportunity to detect disease before irreversible heart failure or other cardiac complications develop. Acute valvular disease can masquerade as respiratory illness or present with nonspecific systemic symptoms, and an astute examination by a primary care physician can direct appropriate care. Therefore, an understanding of the common pathologies and presentations of valvular heart disease is critical. This review focuses on the 2 most common valve lesions, aortic stenosis and mitral regurgitation, and provides an overview of other valve disease topics.

Papillary Muscle Sling Placement for Functional Mitral Regurgitation during Minimally Invasive Valve Surgery

Herein, we report a case of a 39-year-old woman with an 18-month history of peripartum cardiomyopathy. Transthoracic echocardiography revealed severe functional mitral regurgitation and a left ventricular ejection fraction of 20%. Despite optimal medical therapy, she was in New York Heart Association heart failure class IV, with dyspnea on minimal exertion. The patient underwent minimally invasive mitral valve repair with placement of a papillary muscle sling, which improved her symptoms.

Outcome after mitral valve operations with depressed left ventricular function

We retrospectively investigated 42 patients (27 men, 15 women; mean age, 67 years) with severe mitral valve incompetence and endstage cardiomyopathy (ejection fraction<30%) who were operated on between January 2002 and March 2009. Of these, 14 were in New York Heart Association class IV, and 27 were in class III. The etiology was ischemic in 18 patients and idiopathic dilated in 24. Mitral valve repair was performed in 25 patients, and 17 had mitral valve replacement. The mean logistic EuroSCORE was 33.41. The mean follow-up was 44.52 months. There were no perioperative deaths. Three patients died within 30 days postoperatively. Thirty-day mortality was lower than predicted by EuroSCORE (7.14% vs. 33.41%). The median functional class improved from 3 to 2 during follow-up. Ejection fraction improved from 24% to 42% at 6 weeks, then decreased to 33%. The midterm survival rate was 86%, and 81% after 1 and 2 years. Freedom from reoperation at 2 years was 85%; 6 patients needed reoperation for recurrent mitral regurgitation. Despite high operative risk, mitral valve surgery can be performed successfully with acceptably low mortality in patients with endstage cardiomyopathy. Patients experience substantial clinical improvement and a moderate recovery of left ventricular function.

Mitral valve surgery for dilated cardiomyopathy: current status and future roles

There are a large number of patients with functional mitral regurgitation resulting from dilated cardiomyopathy. The decision between surgical correction and medical management of severe mitral regurgitation in heart failure can be difficult. The data regarding long-term benefits and mortality after surgical intervention are contradictory. Recent data suggest that mitral regurgitation can be surgically corrected in heart failure with symptomatic improvements and beneficial reverse remodeling. Contrary to prior beliefs, mitral valve repair can be performed safely with minimal postoperative mortality. Data from multi-institutional, randomized prospective trials will help to elucidate many of the questions and concerns regarding repair of severe functional mitral regurgitation.

Left ventricular mechanics following restrictive mitral annuloplasty for functional mitral regurgitation: two-dimensional speckle tracking echocardiographic study

BACKGROUND

Restrictive mitral annuloplasty (RMA) is widely employed for patients with functional mitral regurgitation (MR). Its improvement of left ventricular (LV) function has been demonstrated by only a gradual increase in LV ejection fraction (EF) in the chronic phase. However, the detailed evaluation of changes in LV function has not been fully elucidated in functional MR patients before and after RMA. Therefore, we performed two-dimensional speckle tracking echocardiography (2D-STE), which enables accurate evaluation of myocardial deformation and rotation that are undetectable by conventional echocardiography.

METHODS

We studied 13 patients (mean age 61 ± 10 years) with functional MR associated with cardiomyopathy undergoing RMA. In addition to conventional echocardiographic measurements, 2D-STE was performed to measure peak systolic radial (RS), circumferential (CS), and longitudinal (LS) strains and twist before and 4 ± 2 weeks after surgery. LV twist was defined as the difference between the apical and basal rotations.

RESULTS

After RMA, EF and LS remained unchanged, but RS and CS were significantly improved at the mid-LV (RS, 20.6 ± 10.8 vs 24.5 ± 11.6%; CS, -9.6 ± 5.2 vs -12.8 ± 5.6%) and at the apex (RS, 15.0 ± 12.2 vs 18.7 ± 8.6%; CS, -4.4 ± 3.0 vs -7.8 ± 4.8%). RS and CS were unchanged at the base. The apical and basal rotations changed significantly, from 3.5°± 0.7° to 9.2°± 2.1°, and -2.1°± 0.7° to -3.8°± 1.0°, respectively. Consequently, the LV twist increased significantly, from 5.6°± 1.0° to 13.0°± 1.9°.

CONCLUSIONS

Radial and circumferential strains and LV twist increased significantly in the early postoperative period in functional MR patients after RMA and concomitant procedures.

Surgical treatment of functional mitral regurgitation

Incidence of functional mitral regurgitation (FMR) is increasing due to aging and better survival after acute myocardial infarction, the most frequent cause of FMR. At the basis of FMR there is a displacement of one of both papillary muscle(s) and/or annular enlargement, which can be primitive or, more often, secondary. There is general agreement that its natural history is unfavorable, as witnessed by a considerable body of evidences. However, even if there is no clear evidence that surgical treatment of FMR changes consistently the outcome of patients with this disease, at least in terms of survival, there are some studies which show that function improves, as well as the global quality of life. The guidelines reflect this uncertainty, providing no clear indications, even in the gradation of severity of the FMR. Surgical techniques are variable and are mainly addressed to the annulus (restrictive annuloplasty), which is only a part of the anatomic problem related to FMR. Insertion of a prosthesis inside the native valve is appearing more and more a valuable option rather than a bail out procedure. On the other side, techniques addressed to modify the position of the papillary muscles appear to be still under investigation and not yet in the armamentarium of surgical treatment of FMR. Even after many years, rules are not established and results are fluctuating, but how and when to treat FMR is becoming more and more a topic of interest in cardiac surgery.

[Successful cardiac resynchronization therapy in a patient with heart failure and ischemic mitral regurgitation: importance of septal flash]

We describe the case of a 76-year-old man with a history of ischemic heart disease and functional mitral regurgitation who over the previous six months had experienced worsening of functional class (NYHA III/IV) under optimal medical therapy, without ischemic symptoms and with negative ischemic tests. Mitral valve annuloplasty was considered. As the patient presented left bundle branch block on the surface ECG, cardiac resynchronization therapy (CRT) was also considered. There was, however, severe biventricular dysfunction and moderate to severe pulmonary hypertension, which are considered predictors of non-response to CRT. On echocardiographic evaluation of mechanical dyssynchrony by two-dimensional strain (2DS), spectral Doppler and color tissue Doppler imaging (TDI)/tissue synchronization imaging (TSI), we observed absence of atrioventricular dyssynchrony and presence of interventricular dyssynchrony, with inconclusive intraventricular longitudinal dyssynchrony, but with marked intraventricular radial dyssynchrony. The latter, immediately observed on the two-dimensional image, and termed multiphasic septal motion or septal flash, was characterized and quantified with 2DS. In our experience, the presence of such septal motion, for which the substrate is predominantly radial dyssynchrony, is a predictor of CRT response. Weighing the risks and benefits of mitral valve annuloplasty without associated revascularization versus CRT, we opted for the latter. Marked improvement in clinical and echocardiographic parameters was observed, compatible with the current criteria for "responder". The improvement began one month after implantation and continued throughout two-year follow-up. In this case, detailed echocardiographic study of mechanical synchrony enabled the most appropriate and effective therapeutic strategy to be chosen.

Surgical Therapy of End-Stage Heart Failure: Understanding Cell-Mediated Mechanisms Interacting with Myocardial Damage

Worldwide, cardiovascular disease results in an estimated 14.3 million deaths per year, giving rise to an increased demand for alternative and advanced treatment. Current approaches include medical management, cardiac transplantation, device therapy, and, most recently, stem cell therapy. Research into cell-based therapies has shown this option to be a promising alternative to the conventional methods. In contrast to early trials, modern approaches now attempt to isolate specific stem cells, as well as increase their numbers by means of amplifying in a culture environment. The method of delivery has also been improved to minimize the risk of micro-infarcts and embolization, which were often observed after the use of coronary catheterization. The latest approach entails direct, surgical, transepicardial injection of the stem cell mixture, as well as the use of tissue-engineered meshes consisting of embedded progenitor cells.

Surgical treatment of functional mitral regurgitation in dilated cardiomyopathy

Functional mitral regurgitation is a significant complication of end-stage cardiomyopathy. Dysfunction of one or more components of the mitral valve apparatus occurs in 39-74% and affects almost all heart failure patients. Survival is decreased in subjects with more than mild mitral regurgitation irrespective of the aetiology of heart failure. The goal of treating functional mitral regurgitation is to slow or reverse ventricular remodelling, improve symptoms and functional class, decrease the frequency of hospitalization for congestive heart failure, slow progression to advanced heart failure (time to transplant) and improve survival. This article reviews the role of mitral valve surgery in patients with heart failure and dilated cardiomyopathy.

Impact of cardiac resynchronization therapy on the severity of mitral regurgitation

AIMS

Functional mitral regurgitation (MR) could be managed by both cardiac resynchronization therapy (CRT) and mitral-valve surgery. Clinical decision making regarding the appropriateness of mitral-valve surgery vs. CRT is a challenging task. This study assessed the prevalence and prognosis of various degrees of functional MR in CRT candidates. Additionally, we sought to identify functional MR patients who either can be adequately managed by CRT only or will need surgery.

METHODS AND RESULTS

Cardiac resynchronization therapy recipients (n= 794) were followed-up for 26 ± 18 months. Mitral regurgitation severity was quantified on scale 0-4. Cardiac resynchronization therapy responders were identified based on improvement in the New York Heart Association class and left-ventricular ejection fraction. Severity of MR and LV reverse remodelling were assessed at 3 and 12 months. Predictors of long-term MR change and CRT response were explored with multivariable models. Mitral regurgitation was present in 86%, with 35% prevalence of advanced MR (grade 3-4). Improvement of MR ≥ 1° after 12 months occurred in 46% of patients. It was relatively more frequent in patients with advanced MR at baseline (63%, P< 0.01). Baseline MR severity and change in MR at 3-month follow-up predicted response to CRT. Patients with ≥ 1° MR improvement at 12 months had more reverse remodelling compared with those with no change or worsening of MR.

CONCLUSIONS

Mitral regurgitation improvement at 3 months predicts CRT response and MR improvement at 12-month follow-up. This finding could have implications for subsequent MR surgical therapies.

Assessment of changes in mitral valve configuration with multidetector computed tomography: impact of papillary muscle imbrication and ring annuloplasty

BACKGROUND

The optimal surgical procedures in functional mitral regurgitation remain controversial. We applied papillary muscle imbrication (PMI) combined with undersized mitral annuloplasty (UMAP). Multidetector computed tomography (MDCT) provides images of different phases of the cardiac cycle, allowing an assessment of the geometry. In the present study, we evaluated the mitral valve configuration and subvalvular apparatus before and after UMAP and/or PMI using MDCT imaging.

METHODS AND RESULTS

We studied 26 patients with functional mitral regurgitation (3+ to 4+) with an ejection fraction ≥35% who underwent diagnostic MDCT examinations before and early after the operation. Of these, 15 underwent UMAP and PMI (UMAP+PMI group) and 11 underwent UMAP (UMAP group). The annular anteroposterior diameter, tenting height, tenting area, and interpapillary muscle distance at end-systole were quantified. The annular anteroposterior diameter, tenting height, and tenting area were significantly decreased after the operation in both groups. Whereas the average change in annular anteroposterior diameter, tenting area, and interpapillary muscle distance did not differ between the 2 groups, the average change in tenting height was greater in the UMAP+PMI group than in the UMAP group (5.1±1.3 versus 3.8±2.3 mm, P=0.036). There was a significant correlation between the change in interpapillary muscle distance and the change in tenting height in the UMAP+PMI group (r=0.788, P=0.0005).

CONCLUSIONS

Our results examined with MDCT indicated that UMAP combined with PMI improved leaflet tethering compared with UMAP, reflecting differences in the effects of the surgical procedures used, and suggested that concomitant PMI might be beneficial in some cases.

Mitral valve surgery in advanced heart failure

The appropriateness and timing of mitral valve surgery in patients with advanced heart failure and severe mitral regurgitation remains controversial. Recent surgical results provide evidence for beneficial effects on left ventricular remodeling and functional capacity. Given the absence of randomized trials comparing the outcomes of mitral valve surgery to medical therapy, however, clinical decision making regarding surgery for these fragile patients poses a dilemma to thoughtful clinicians. This paper reviews the pathophysiology of mitral regurgitation in heart failure and proposes an integrated approach to management.

Beating heart video-assisted mitral valve surgery: a useful technique for high-risk patients

BACKGROUND

Beating-heart valve surgery through a sternotomy has been used as an excellent myocardial protection strategy in high risk patients. Minimally invasive approaches have reduced the trauma and enhanced the recovery of patients undergoing heart surgery. We hypothesized that high-risk patients undergoing mitral valve surgery will benefit from a combination of these two approaches.

METHODS

A 52-year-old male with dilated cardiomyopathy and left ventricular function of 15% was referred for surgery because of congestive heart failure.

RESULTS

Using a 4-cm right minithoracotomy and femoral cannulation for cardiopulmonary bypass, successful beating-heart video-assisted mitral valve repair was performed. The adequacy of myocardial protection was confirmed by absence of ischemic electrophysiologic changes. The patient was discharged home on the 6(th) postoperative day.

CONCLUSION

Beating-heart strategy can be combined with a minimally invasive approach in patients with severely reduced ventricular function, who require mitral valve surgery.

Surgery of secondary mitral insufficiency in patients with impaired left ventricular function

BACKGROUND

Secondary mitral insufficiency (SMI) is an indicator of a poor prognosis in patients with ischemic and dilated cardiomyopathies. Numerous studies corroborated that mitral valve (MV) surgery improves survival and may be an alternative to heart transplantation in this group of patients.The aim of the study was to retrospectively analyze the early and mid-term clinical results after MV repair resp. replacement in patients with moderate-severe to severe SMI and left ventricular ejection fraction (LVEF) below 35%.

METHODS

We investigated 40 patients with poor LVEF (mean, 28 +/- 5%) and SMI who underwent MV repair (n = 26) resp. replacement (n = 14) at the University Hospital Muenster from January 1994 to December 2005. All patients were on maximized heart failure medication. 6 pts. had prior coronary artery bypass grafts (CABG). Twenty-seven patients were in New York Heart Association (NYHA) class III and 13 were in class IV. Eight patients were initially considered for transplantation. During the operation, 14 pts had CABG for incidental disease and 8 had tricuspid valve repair. Follow-up included echocardiography, ECG, and physician's examination and was completed in 90% among survivors. Additionally, the late results were compared with the survival after orthotope heart transplantation (oHTX) in adults with ischemic or dilated cardiomyopathies matched to the same age and time period (148 patients).

RESULTS

Three operative deaths (7.5%) occurred as a result of left ventricular failure in one and multiorgan failure in two patients. There were 14 late deaths, 2 to 67 months after MV procedure. Progress of heart failure was the main cause of death. 18 patients who were still alive took part on the follow-up examination. At a mean follow-up of 50 +/- 34 (2-112) months the NYHA class improved significantly from 3.2 +/- 0.5 to 2.2 +/- 0.4 (p < 0.001). The LVEF improved significantly from 29 +/- 5% to 39 +/- 16 (p < 0.05). There were no differences in survival after MV repair or replacement. The 1-, 3-, 5-year survival rates in the study group were 80%, 58% and 55% respectively. In the group of patients after oHTX the survival was accordingly 72%, 68%, 66% (p > 0.05).

CONCLUSION

High risk mitral valve surgery in patients with cardiomyopathy and SMI offers a real mid-term alternative method of treatment of patients in drug refractory heart failure with similar survival in comparison to heart transplantation.

Clinical outcomes of mitral valve repair with the Colvin-Galloway Future Band: a single-center experience

OBJECTIVES

In 2001, a semirigid band (Colvin-Galloway Future Band, Medtronic, Inc., Minneapolis, Minnesota, USA) for mitral valve repair came onto the market. We report our experience of the correction of all types of mitral regurgitation using this device.

METHODS

From August 2003 to December 2006, 140 patients (71% men, mean age 64 +/- 11 years) underwent valvuloplasty with this device for all types of mitral regurgitation: 94 (67%) degenerative, 34 (24%) postischemic, 11 (8%) dilative cardiomyopathy, and one (1%) postendocarditic. The patients underwent clinical and echocardiographic evaluation preoperatively, postoperatively before discharge, and after a median follow-up of 7 months (25th-75th percentile, 4-24 months).

RESULTS

Total mortality was 6.4% (nine out of 140 patients): four patients (2.8%) died within 30 days (early death) and five died subsequently (the cause was cardiac in one case). Predischarge echocardiographic examination revealed a reduction in mitral regurgitation of at least 2 degrees in 99.2% of patients and the absence of systolic anterior movement. At the last follow-up, we recorded an improvement in New York Heart Association functional class (2.4 +/- 0.9 vs. 1.1 +/- 0.4, P < 0.0001), a significant reduction in the degree of mitral regurgitation (3.5 +/- 0.9 vs. 0.9 +/- 0.5, P < 0.0001), an increase in ejection fraction (54 +/- 11 vs. 55 +/- 9, P = 0.09), and a significant reduction in end-diastolic diameter (59 +/- 6 vs. 55 +/- 6, P < 0.0001). Two patients were reoperated on for mitral valve replacement, and no postoperative thromboembolic events occurred.

CONCLUSION

Our experience shows that the Colvin-Galloway Future Band yields good results in mitral valvuloplasty for all types of mitral regurgitation. We are encouraged to continue using this device.