Mitral Regurgitation

the bSSFP sequences, with very short echo times, show only limited signal loss from turbulent regions, the non- velocity compensated sequence results in loss of signal from voxels located in the shear layers on either side of the core of high velocity jets. This is explained by dephasing of signal from voxels containing a wide range of velocities in the shear layer bounding a jet. In contrast to the dark shear layer voxels, bSSFP voxels lying within a coherent jet core, if present, show bright signal (Fig 6b, see also addi- tional file 1: Figure 6b movie). For these reasons, suitably aligned bSSFP slices, either aligned with or transecting the jet, can show the width of any coherent jet core, which reflects the width of the regurgitant orifice (Appendix). Whereas the jets of mild mitral regurgitation will be too narrow to give bright central voxels, jet(s) of severe mitral regurgitation are likely to include jet core(s) either broad enough to give bright central voxels outlined by dark, or else extensive enough along the line of failed coaptation to be visible in several slices of the cine stack. In either case, a bSSFP cine aligned to transect the regurgitant jet core may also be valuable to assess the cross sectional extent of each jet. The principle illustrated in Fig 2 applies to the depiction of jet boundaries as well as leaflets. A fur- ther feature of severe mitral regurgitation is reversal of flow in the pulmonary veins during LV systole, which may be visible in the 4 chamber and certain mitral stack cines. Discussion

The main results of the our study showed that the LVEF and MVd were not significantly influenced after mitral valve repair. However, the coaptation height was significantly increased after the operation. Interestingly, CH after heart resuscitation showed a statistically signifi- cant negative correlation with degree of mitral regurgita- tion 12 months after operation, which meant CH after heart resuscitation may be an important predictive factor for the post-operative mitral regurgitation. Some other researches have also investigated the change of the mi- tral valve morphology after mitral annuloplasty. It was reported that the mitral annuloplasty with ring could significantly improve the stresses and the valve coapta- tion with annular dilatation [13]. The reconstruction of the posterior leaflet compressive stresses and nearnor- mal coaptation was crucial to the mitral annuloplasty. It was also reported that the anuloplasty ring could signifi- cantly improve the mitral valve coaptation by reducing the delayed action of the leaflet and preventing the mi- tral regurgitation in the case of acute left ventricular is- chemia after ring implantation [14]. In a total, the normal coaptation is very important in the mitral annuloplasty.

Ischemic mitral regurgitation (IMR) is a frequent complication after acute myocardial infarction (AMI) and has a worse prognosis, regardless of the severity. The mechanism of chronic IMR is the mismatch between the two intraventricular forces. IMR occurs when the tethering forces are superior to the closing forces. The diagnosis of IMR is demanding because IMR can alter its severity under different loading conditions. The treatment selection remains challenging because of variable clinical outcomes and the existence of conflicting data. Focusing on the correction of the mismatch between closing and tethering forces is one of the therapeutic options to treat IMR. Additional trials, including a randomized investigation with a long-term follow-up periods, may be required to evaluate the efficacy of surgical treatments and establish robust scientific evidence in this challenging patient population.

Mitral valve annuloplasty (MAP) has been the gold standard for surgical treat- ment of ischemic mitral regurgitation (IMR) [1]. However, high rates of persis- tence and/or recurrence of mitral regurgitation (MR) following MAP have been observed in patients with a dilated left ventricle (LV), and the surgical results of MAP have not been satisfactory. Recently, new and alternative surgical proce- dures that target the valvular, subvalvular, or ventricular levels have been at- How to cite this paper: Furukawa, K.,

Background: The treatment of patients with aortic regurgitation (AR) or mitral regurgitation (MR) relies on the accurate assessment of the severity of the regurgitation as well as its effect on left ventricular (LV) size and function. Cardiovascular Magnetic Resonance (CMR) is an excellent tool for quantifying regurgitant volumes as well as LV size and function. The 2008 AHA/ACC management guidelines for the therapy of patients with AR or MR only describe LV size in terms of linear dimensions (i.e. end-diastolic and end-systolic dimension). LV volumes that correspond to these linear dimensions have not been published in the peer-reviewed literature. The purpose of this study is to determine the effect of regurgitant volume on LV volumes and chamber dimensions in patients with isolated AR or MR and preserved LV function.

tify persistent lesions that require additional immediate surgical intervention [7,8]. Residual moderate or severe MR will usually necessitate a return to CPB for further evaluation and definitive surgery. However, little is known about the outcome of patients who have less than moderate residual MR after repair evaluated by means of intraoperative TEE. In an early study, Fix et al. analyzed early outcomes among 76 patients with grade mild-to-moderate residual MR by post-pump intraoperative echocardiography and compared them with 76 well-matched patients who had no residual MR by post-pump echocardiography [10]. In- hospital morbidity measured by the frequency of respira- tory complications, strokes, time in intensive care unit, and duration of hospital stay was reported to be higher in the patients with no residual MR after repair. Hospital mortality was not significantly different. Similar to this study we found no difference in in-hospital mortality among patients with different grades of residual MR. However, differently from this study we did not found a significant difference in in-hospital morbidity between patients with no residual MI and less than moderate resid- ual MI. Moreover, we found a trend favouring patients with no residual MI with respect to the need of reinterven- tion for recurrent severe mitral regurgitation and a com- posite of postintervention complications. The different

Investigating the outcomes of surgical treat- ment and the accompanying diagnostic procedures is basic to the development of smarter diagnostic and therapeutic modalities to a disease. With regard to a very specific disease with a relatively few patients, no data for large groups of patients can be collect- ed and summarized in a single institution, i.e. there is no way to carry out the classical design model for target and control group. Another aspect of difficulty is professional and ethical standards, which should not allow the use of treatment considered to be less effective to be applied to patients for the sake of re- search. Having in mind the above, randomization of patients for mitral valve repair performed as a con- comitant procedure with surgical revascularization: coronary artery bypass grafting + mitral valve re- pair (CABG+MVRep) or with CABG only, is hard- ly achievable. Different models are needed to provide reliable and trustworthy information about the out- comes of this treatment. An applicable model may be the formal stratification of patients included in a study by P. Panayotov from 2013 (1) on advanced methods for diagnosis and surgical treatment of sig- nificant chronic ischemic mitral regurgitation.

Mitral regurgitation (MR) continues to impose significant morbidity and mortality on patients. Since even asymptomatic MR typically progresses to left ventricular dilatation, left ventricular failure, worsening MR, and eventual symptom onset, surgical therapy has traditionally been advocated to break this cycle. However, though effective, even mitral valve repair (MVR), as opposed to replacement, has been associated with first- time operative mortality rates in the 2% range, and reoperative mortality rates as high as 8%. 1 Accordingly, the MitraClip system has emerged as a transcatheter method

Notes: (A) The MitraClip system with the steerable guide catheter, the clip delivery system, and the MitraClip positioned in the stabilizer. (B) The MitraClip is attached to the delivery system. The two arms are open, and the grippers are almost touching the arms. (C) The MitraClip is being positioned directly below the mitral valve with each leaflet on one side between the clip arms and the grippers in the region of mitral regurgitation. (D) Surgical view from the left atrium onto the valve: the grippers fix the leaflets to the clip arms, and the clip arms are closed, resulting in a dual orifice during diastole. The clip is still attached to the delivery system. (E) The clip is released from the delivery system after grasping the anterior and posterior mitral leaflet (pictures and graphics courtesy of Abbott Laboratories).

Background: The key mechanism of functional mitral regurgitation (FMR) in cardiomyopathy is leaflet tethering caused by displacement of the papillary muscles (PM) due to left ventricular dilatation. The attendant remodeling proc- ess is characterized by intraventricular widening between both PM. Recently, surgical ventricular restoration (SVR) has been proposed as a technique to reduce leaflet tethering by improving ventricular geometry. However, it is unknown how SVR improve FMR. Methods and Results: From 2003 to 2010, we surgically treated FMR in 100 patients with idiopathic dilated cardiomyopahy (DCM) or ischemic cardiomyopathy (ICM). Of those, we performed posterior wall exclusion procedures by either resection (the Batista procedure, n = 13) or plication (n = 19) to approximate papillary muscle distance in a total of 32 patients (DCM in 17, ICM in 15), and these patients formed the cohort of this study. There were two 30-day mortalities (6.3%). There was no significant change in left ventricular ejection fraction, however, the size of the left ventricle, degree of MR, tethering height and distance of PM significantly decreased after operation and well maintained at the mean follow up of 3.3 ± 2.1 years. Conclusions: Posterior wall resection or plication with PM approximation provides excellent reduction of leaflet tethering and MR. Thus, reduction of PM distance may be helpful to treat FMR due to leaflet tethering.

Abstract It is to be investigated and verified that vena contracta width (VCW) obtained from color Doppler images and effective regurgitant orifice area (EROA) obtained from the VCW is capable of quantifying the severity of mitral regurgitation (MR). A mathematical expression has been developed between VCW and EROA. Vena contracta width is an efficient method for grading the severity of MR, but it is very difficult to locate this narrowest part exactly in transthoracic echocardiography as well as in transesophageal echocardiography. So, indeed, there is a need to develop a method which is capable of finding out the vena contracta width. A comparison has also been made between the results obtained using the proposed computing method and the results obtained by the clinicians, manually. For this analysis have been done from the results obtained with automatic VCW finding method and with clinical data for severity grading.

Results: Additional mitral valve repair techniques involved triangular resection ( n = 15 patients), quadrangular resection with sliding plasty ( n = 12), neochordoplasty ( n = 52), and commissural plication ( n = 26). Prolapse of ≥ 2 anterior and posterior leaflet scallops occurred in 22 (39%) and 30 (54%) patients, respectively. During follow-up, 10 (17.8%) patients developed moderate or severe mitral regurgitation. Whereas prolapse or tethering was observed early after neochordoplasty or quadrangular resection, recurrent regurgitation occurred late after commissural repair. Five-year freedom from recurrent moderate or severe mitral regurgitation rates was 71.1 ± 11.0%. Conclusions: Seventeen percent of patients developed recurrent mitral regurgitation during follow-up. Repair failure in the early phase occurred owing to aggressive resection of the posterior mitral leaflet or maladjustment of the artificial neochordae. Recurrent mitral regurgitation might occur in the late phase even after acceptable commissural repair. A sequential approach may be useful to improve the quality of mitral valve repair in bileaflet lesions.

The superiority of valve sparing techniques as compared to valve replacement for the treatment of mitral regurgita- tion has been widely demonstrated with regard to more favourable mortality and morbidity rates [8]. Reconstruc- tive procedures ensure a more effective and durable com- petency of the repaired mitral valve [8]. However, early experiences with mitral valve repair in the presence of anterior leaflet prolapse have been less favourable due to more complex mechanisms of valvular incompetence and more demanding repairing techniques. Prolapse of the anterior leaflet is more difficult to repair because it is hardly possible to perform a resection of the anterior leaf- let. The height of the chordae underlying the anterior leaf- let must be assessed and chords may be grossly elongated or ruptured and make the AML flail. Correction of anterior leaflet prolapse, can be more difficult than posterior leaf- let repair; redundancy of the posterior leaflet lends itself to plication or segmental excision, but prolapsing por- tions of the anterior leaflet are often not redundant nor amenable to excision. Poor results after anterior leaflet resections have led to a variety of techniques including chordal transposition, chordal shortening, and chordal replacement. The aetiology and responsible mechanisms might be negative prognostic factors for the success of mitral valve repair and could lead to a higher incidence of recurrent mitral regurgitation and need for reintervention. We studied patients who underwent repair of mitral valve for mitral regurgitation due to mitral valve prolapse. We found that patients with prolapse of the anterior leaflet had a higher proportion of residual mitral regurgitation

Results: Modulation of various blood proteins expression was examined in patients suffering from different grades of mitral regurgitation (mild, moderate and severe) compared to healthy controls. To this end, several routine clinical assays and the multi analyte profile technology targeting 184 proteins were used. High‑density lipoprotein, apoli‑ poprotein‑A1, haptoglobin and haptoglobin‑α2 chain levels significantly decreased proportionally to the degree of mitral regurgitation when compared to controls. High‑density lipoprotein and apolipoprotein‑A1 levels were associ‑ ated with effective regurgitant orifice area and regurgitant volume. Apolipoprotein‑A1 was an independent predictor of severe mitral regurgitation. Moreover, with ordinal logistic regression, apolipoprotein‑A1 remained the only inde‑ pendent factor associated with mitral regurgitation. In addition, myxomatous mitral valves were studied by immu‑ nocytochemistry. We observed an increase of LC3, the marker of autophagy, in myxomatous mitral valves compared with healthy mitral valves.

Abstract: Since the first mitral valvuloplasty in 1923, the technique of mitral valvuloplasty has matured over the years and now has become the first-line treatment, especially in patients with myxomatous mitral regurgitation (MR). We have highlighted some of the major problems that are encountered with the various etiologies of MR. We believe that repair is always the optimal surgical procedure for any of the above etiologies if it is consistent with a long-term result. However, replacement has shown to be a safer procedure in some instances such as severe functional MR or destructive endocarditis.

patients in whom the benefit of valve replacement is un- certain and those with a temporary contraindication to valve replacement. Mitral regurgitation (MR) is com- monly observed in patients with severe AS [5]. The reso- lution of AS, by means of SAVR or TAVR, leads to an immediate drop in left ventricular (LV) systolic pressure, which reduces the pressure gradient across the mitral valve and, thus, improves MR severity. On the other hand, the risk for mortality increases in patients with se- vere AS in whom MR fails to improve after SAVR or TAVR [6–8]. However, changes in MR after BAV and identification of patients with severe AS for whom BAV could be of benefit to decrease MR remain to be clari- fied. Accordingly, the aim of our study was to investigate the mid-term effect of BAV on MR in patients with se- vere AS.

Objective The impact of the severity of secondary mitral regurgitation (MR) on the risk of death and heart failure (HF) hospitalisations in patients with reduced left ventricular (LV) systolic function is poorly defined. The study sought to identify the incremental risk of secondary MR in patients with reduced LV systolic function. Methods We studied 615 consecutive patients with LV ejection fraction ≤35% by transthoracic echocardiography at a single medical centre. Patients were divided into three groups of no MR, mild, or moderate to severe MR. The median follow-up was 2.9 years. The primary endpoint was a composite of death or HF hospitalisations. Results Compared with patients with no MR, the risk of death or HF hospitalisations was higher for mild MR (HR 1.7, P=0.003) and moderate to severe MR (HR 2.7, P<0.001). The risk was also higher for the component endpoints of HF hospitalisations (mild MR: HR 2.3, P=0.001; moderate to severe MR: HR 3.5, P<0.001) and death (mild MR: HR 1.6, P=0.033; moderate to severe MR: HR 2.6, P<0.001). After adjustment for other covariates, MR was no longer significantly associated with death or HF hospitalisations, or death alone, but remained significantly associated with HF hospitalisations (mild MR: HR 1.7, P=0.028; moderate to severe MR: HR 2.2, P=0.002).

Case presentation: Herein, we report the case of a 42-year-old man who was scheduled to undergo mitral valve plasty for severe mitral regurgitation. He had been diagnosed with moyamoya disease on the onset of cerebral ischemia at 41 years of age. During the cardiac surgical procedure, the patient was maintained on inhalation anesthesia with 1 to 1.5 % sevoflurane. Sevoflurane causes cerebral vasodilation followed by increased cerebral blood flow, and moreover we expected a sevoflurane preconditioning-induced neuroprotective effect. In addition, we used pulsatile perfusion support to maintain cerebral circulation with intra-aortic balloon pumping during the cardiopulmonary bypass. We aimed to keep the mean arterial pressure constantly above 70 mmHg. We were able to maintain regional cerebral oxygen saturation at 80 % of the baseline value, and could not detect the progression of neurological deficits using follow-up brain single photon emission computed tomography. The patient was discharged 16 days after admission.

Functional Mitral Regurgitation (FMR) defined as a regur- gitation that seen with structurally normal valve leaflets. It occurs as a consequence of systolic LV dysfunction caused by ischemic or nonischemic cardiomyopathy. Functional MR occurs in roughly 20–25% of patients following MI and 50% of those with CHF [1,2]. Any degree of FMR in patients with LV dysfunction conveys adverse prognosis, [2-8], with a graded relationship between severity of regurgitation and reduced survival [2,4]. Although global LV dilation and sphericity has been attributed to FMR by alteration in mitral annulus and subvalvular apparatus, and ultimately incomplete coaptation, but local LV remodeling and mitral valve deformation seems to be more important determinants of FMR severity. It is also suggested from propensity for recurrence of FMR follow- ing ring annuluplasty, [1-3,6-11]and addressed adjunctive surgical operative techniques to correct subvalvular changes as a major target to prevent residual or recurrent regurgitation following mitral valve repair procedures [1,3,11,12]. Optimal repairing of FMR requires an under- standing of its mechanisms and it may be useful to use some echocardiographic predictors as a surrogate for its potential severity and its major mechanism for planning therapeutic options. Therefore, we undertook a quantita- tive study of patients with LV dysfunction in order to determine the most important determinants of FMR severity.

Background: Structural changes to the mitral annulus occur following aortic valve replacement (AVR) for severe aortic stenosis which may influence functional mitral regurgitation (MR). Me- thods: A retrospective review of 44 patients who underwent open AVR for aortic stenosis at a sin- gle center from 2010-2013 was performed. Patients undergoing concomitant aortic root surgery or with severe MR were excluded. MR was evaluated with preoperative and postoperative trans- thoracic echocardiograms. Univariate and multivariable analyses were performed to assess for factors associated with postoperative MR improvement and worsening. Results: Prior to AVR, none had severe MR, 5% (2 patients) had moderate, 9% (4 patients) mild-to-moderate, 46% (20 patients) mild, and 23% (9 patients) trace MR. Of patients with pre-operative MR, 44% (16 pa- tients) experienced improvement of MR. Six patients had worsening of MR and the remaining 22 patients had no change. Cases of more severe MR were more likely to improve compared with mild or trace MR (P = 0.04). MR worsening was significantly more likely in patients with bicuspid aortic valves (83% vs. 24%; P = 0.004), and with larger aortic annulus diameters (P = 0.03). MR worsen- ing was less frequent in cases of mitral annular calcification (0% vs 42%; P = 0.04) and left atrial enlargement (17% vs 65%; P = 0.03). Logistic regression analysis revealed negative predictors for MR improvement were mitral annular calcification (P = 0.04) and larger aortic annulus diastolic diameter (P = 0.05). Conclusion: Structural factors such as aortic annular size, mitral annular cal- cification and valve morphology may impact MR following AVR and should be investigated further as potential targets of surgical therapy.