Characterization and Long-Term Prognosis of Patients with Different Phenotypes of Dilated Cardiomyopathy

BACKGROUND

Long-term prognosis of dilated cardiomyopathy (DCM) in the Chinese population is lacking, and the left ventricular (LV) hypertrabeculation phenotype usually overlaps with DCM.

OBJECTIVES

The study aims to investigate whether the presence of the LV hypertrabeculation phenotype confers additional adverse prognostic information for DCM patients.

METHODS

We retrospectively reviewed all DCM patients (≥18 years of age at diagnosis) hospitalized in the Peking Union Medical College Hospital between September 2002 and September 2022. The eligible patients were divided into two groups based on echocardiography at diagnosis: the isolated DCM (n = 353), and DCM with the LV hypertrabeculation phenotype (n = 97). The primary endpoint was major adverse cardiac events (MACEs), and multivariate Cox hazards regression models were used to compare the endpoints between the two groups.

RESULTS

During a mean follow-up time of 4.6 years, there was no significant difference in the primary endpoint between the isolated DCM and DCM with the LV hypertrabeculation phenotype (p = 0.19). The risk of MACEs in the first 5 years was significantly higher in DCM with the LV hypertrabeculation phenotype than isolated DCM (adjusted HR [95%CI]: 1.83 [1.21-2.77]) and after 5 years the effect of the LV hypertrabeculation phenotype as a prognostic attenuated. Subgroup analysis found a significant interaction for the incidence of MACEs between sex and DCM subtypes (p for interaction = 0.01).

CONCLUSIONS

DCM with LV hypertrabeculation phenotypes had a higher early (first 5 years) risk of MACEs. For males, the presence of LV hypertrabeculation phenotypes might be an important clue for identifying high-risk DCM patients.

Echocardiographic quantification of mitral apparatus morphology and dynamics in patients with dilated cardiomyopathy

Mitral regurgitation is among the most common valvular heart diseases. Mitral regurgitation in patients with dilated cardiomyopathy is a complex pathology involving annular dilatation, papillary muscle displacement, systolic leaflet tethering, and left ventricular remodeling. Quantification of mitral apparatus damage in these patients is essential for successful interventional and surgical therapy. Mitral regurgitation in the presence of dilated cardiomyopathy is classified as Carpentier type IIIB, with restricted leaflet mobility as a standard feature. Echocardiography allows accurate evaluation of the complex anatomy and function of the mitral apparatus. Updated guidelines recommend two-dimensional followed by systematic three-dimensional echocardiographic evaluation in patients with mitral regurgitation. New three-dimensional echocardiographic software packages provide many parameters that help identify the precise morphology and function of the various components of the mitral apparatus, helping to determine the etiology of mitral regurgitation and evaluate disease severity. This review provides the first point-by-point approach to the assessment of all old and new echocardiographic methods, from the simplest to the most complex, used to examine the components of the mitral valve apparatus in patients with dilated cardiomyopathy. Although these parameters are still under research, this information will be helpful for establishing therapeutic procedures in a disease with a poor prognosis.

Predictor of the Postoperative Swelling After Craniotomy for Spontaneous Intracerebral Hemorrhage: Sphericity Index as a Novel Parameter

Objective

Spontaneous intracerebral hemorrhage is a serious type of stroke with high mortality and disability rates. Surgical treatment options vary; however, predicting edema aggravation is crucial when choosing the optimal approach. We propose using the sphericity index, a measure of roundness, to predict the aggravation of edema and guide surgical decisions.

Methods

We analyzed 56 cases of craniotomy and hematoma evacuation to investigate the correlation between the sphericity index and patient outcomes, including the need for salvage decompressive craniectomy (DC).

Results

The patients included 35 (62.5%) men and 21 (37.5%) women, with a median age of 62.5 years. The basal ganglia was the most common location of hemorrhage (50.0%). The mean hematoma volume was 86.3 cc, with 10 (17.9%) instances of hematoma expansion. Cerebral herniation was observed in 44 (78.6%) patients, intraventricular hemorrhage in 34 (60.7%), and spot signs in 9 (16.1%). Salvage DC was performed in 13 (23.6%) patients to relieve intracranial pressure. The median follow-up duration was 6 months, with a mortality rate of 12.5%. The sphericity index was significantly correlated with delayed swelling and hematoma expansion but not salvage DC.

Conclusions

The sphericity index is a promising predictor of delayed swelling and hematoma expansion that may aid in the development of surgical guidelines and medication strategies. Further large-scale studies are required to explore these aspects and establish comprehensive guidelines.

Outcomes and predictors of patients with moderate or severe functional mitral regurgitation and nonischemic dilated cardiomyopathy

BACKGROUND

Patients with functional mitral regurgitation (FMR) and nonischemic dilated cardiomyopathy (DCM) are associated with high mortality.

OBJECTIVES

Our study aimed to compare the clinical outcomes between different treatment strategies and identify predictors associated with the adverse outcomes.

METHODS

A total of 112 patients with moderate or severe FMR and nonischaemic DCM were included in our study. The primary composite outcome was all-cause death or unplanned hospitalization for heart failure. The secondary outcomes were individual components of the primary outcome and the cardiovascular death.

RESULTS

In this study, the primary composite outcome occurred in 26 patients (44.8%) in mitral valve repair (MVr) group and 37 patients (68.5%) in medical group (hazard ratio [HR], 0.28; 95% confidence interval [CI], 0.14-0.55; p < .001). The 1-, 3-, and 5-year survival rates for patients with MVr were 96.6%, 91.8%, and 77.4%, respectively, which were significantly higher than that of medical group: 81.2%, 71.9%, and 65.1%, respectively (HR, 0.32; 95% CI, 0.12-0.87; p = .03). Left ventricular ejection fraction (LVEF) < 41.5% (p < .001) and atrial fibrillation (p = .02) were independently associated with the primary outcome. LVEF < 41.5% (p = .007), renal insufficiency (p = .003), and left ventricular end-diastolic diameter > 66.5 mm (p < .001) were independently associated with heightened risk for all-cause death.

CONCLUSION

Compared with medical therapy, MVr was associated with a better prognosis in patients with moderate or severe FMR and nonischemic DCM. We observed that LVEF < 41.5% was the only independent predictor of the primary outcome and all individual components of secondary outcomes.

The current diagnosis and treatment of high-risk patients with chronic primary and secondary mitral valve regurgitation

Mitral valve regurgitation (MR) is due primarily to either primary degeneration of the mitral valve with Barlow's or fibroelastic disease or is secondary to ischemic or nonischemic cardiomyopathies. Echocardiography is essential to assess MR etiology and severity, the remodeling of cardiac chambers and to characterize longitudinal chamber changes to determine optimal therapies. Surgery is recommended for severe primary MR if persistent symptoms are present or if left ventricle dysfunction is present with an EF <60% or a left ventricle end-systolic diameter ≥40 mm. For secondary MR, therapy of heart failure with vasodilators and diuretics improves forward cardiac output. Coronary artery bypass grafts (CABG) or percutaneous coronary intervention (PCI) should be considered for severe MR due to ischemia. This review summarizes the pathophysiology, the characteristics, the management and the different interventions for high risk patients with chronic primary and secondary MR.

Predicting clinical outcome by indexed mitral valve tenting in functional mitral valve regurgitation

OBJECTIVES

Mitral valve (MV) tenting parameters are indicators of left ventricular remodelling severity and may predict outcome in functional mitral regurgitation (FMR). We hypothesised that indexing of MV tenting area to body surface area (BSA), to mitral annulus diameter or gender-adjusted analysis of tenting parameters may improve their prognostic value.

METHODS

We identified retrospectively 240 patients with consecutive FMR (mean age 68±10 years; men=135) from our institutional database who underwent isolated MV annuloplasty during a period of 7 years (2010-2016). Using preoperative two-dimensional transthoracic echocardiographic images, MV tenting parameters including tenting area, tenting height and annulus diameter were systematically assessed. Follow-up protocol consisted of chart review and structured clinical questionnaire. Primary study endpoint was the composite of death and adverse cardiac events (ie, MV reoperation, cardiac resynchronisation therapy implantation, ventricular assist device implantation or heart transplantation).

RESULTS

BSA-indexed MV tenting area was identified as independent predictor of primary study endpoint (HR 1.9; 95% CI 1.1 to 3.5; p=0.02). After cut-off point analysis, BSA-indexed MV tenting area >1.35 cm²/m² was significantly associated with primary study outcome (HR 2.3; 95% CI 1.3 to 4.0; p=0.003). Annulus-indexed MV tenting area showed only a tendency towards primary study endpoint prediction (HR 2.8; 95% CI 0.6 to 12.6; p=0.17). Between female and male patients, BSA-indexed MV tenting area was similar (1.42±0.4 cm²/m² vs 1.45±0.4cm²/cm²; p=0.6) and gender was not associated with primary study outcome (HR 0.8; 95% CI 0.5 to 1.4; p=0.5).

CONCLUSION

In our FMR cohort, BSA-indexed MV tenting area showed the strongest association with negative outcomes following isolated MV annuloplasty. Patients with BSA-indexed MV tenting area >1.35cm²/m² could potentially benefit from additional surgical maneuvers addressing left ventricular remodelling.

Mitral valve dysplasia in eight English Springer Spaniels

INTRODUCTION

To describe the signalment, physical examination, and echocardiographic findings of a series of English Springer Spaniels (ESSs) diagnosed with congenital mitral valve dysplasia (MD).

ANIMALS

Eight client-owned ESSs with congenital MD referred for murmur investigation and/or suspected congestive heart failure (CHF).

MATERIALS AND METHODS

Retrospective case series. Medical records and echocardiograms were reviewed to collect relevant data. Echocardiograms were assessed for the following abnormalities consistent with MD: thickened valve leaflets or leaflet tips, a 'hockey stick' appearance to the valve leaflets, abnormal length of one leaflet with respect to the other, and tethering of one or both leaflets to the papillary muscles.

RESULTS

All eight dogs showed the typical echocardiographic lesions associated with MD: thickened leaflet tips (5/8), 'hockey stick' appearance (5/8), elongated anterior leaflet (4/8), tethering of one or both leaflets (7/8). Seven of the eight dogs presented in CHF. Six of the eight dogs had left ventricular dilation in both systole and diastole. Two of the eight dogs had reduced systolic function as assessed by ejection fraction/fractional shortening; however end-systolic volume index was increased in 6/8 dogs. Two dogs subsequently developed atrial fibrillation.

CONCLUSIONS

Congenital MD should be considered in ESSs with a left-sided apical systolic murmur, particularly in younger dogs. The valve changes seen are similar to those reported in other breeds with MD (thickened leaflet tips, hockey stick appearance to open leaflet tips, abnormal leaflet tethering, abnormally shaped leaflets) and may result in marked remodeling and CHF.

Prognostic value of mitral valve tenting area in patients with functional mitral regurgitation

OBJECTIVES

Mitral valve (MV) repair in functional mitral regurgitation is still associated with suboptimal outcomes. Our goal was to determine whether the clinical outcome following MV repair correlates with preoperative tenting parameters.

METHODS

We retrospectively identified consecutive patients with functional mitral regurgitation who underwent an isolated MV annuloplasty during a 7-year period (2010-2016) from our institutional database. Preoperative tenting parameters (i.e. tenting height, coaptation length, tenting area, posterior mitral leaflet and anterior mitral leaflet angles and interpapillary muscle distance) were systematically measured. The primary end point was the composite of survival and freedom from adverse cardiac events. The follow-up protocol consisted of a structured clinical questionnaire and an analysis of the echocardiographic data.

RESULTS

A total of 240 patients (mean age 67.8 ± 9.8 years, 57% of men) were analysed. The overall 5-year survival rate for the whole study cohort was 74.7 ± 4.2%, and freedom from adverse cardiac events was 84.8 ± 3.4%. A tenting area ≥2.4 cm2 was identified as a cut-off value, independently predicting the composite primary study end point (hazard ratio 2.0; P = 0.03). Furthermore, a Kaplan-Meier analysis revealed a strong tendency towards worse 5-year outcomes in patients with a tenting area ≥2.4 cm2 (n = 153) versus patients with a tenting area <2.4 cm2 (n = 87) (65.3 ± 5.5% vs 77.1 ± 6.3%; P = 0.06).

CONCLUSIONS

MV annuloplasty is associated with acceptable clinical and echocardiographic outcomes in patients with functional mitral regurgitation 5 years postoperatively. A preoperative tenting area ≥2.4 cm2 showed a strong trend towards a worse 5-year survival rate and an increased risk of adverse cardiac events after an isolated MV annuloplasty.

Left ventricle and mitral valve reverse remodeling in response to cardiac resynchronization therapy in nonischemic cardiomyopathy

BACKGROUND

Cardiac resynchronization therapy (CRT) improves left heart geometry and function in nonischemic cardiomyopathy (NICMP). We aimed to detail the effects of CRT on left ventricular (LV) and mitral valve (MV) remodeling using 2-dimensional transthoracic echocardiography.

METHODS

Forty-five consecutive patients with NICMP who underwent CRT implantation between 2009 and 2012, and had pre-CRT and follow-up echocardiograms available, were included. Paired t test, linear and logistic regression, and Kaplan-Meier survival analyses were used for statistical assessment.

RESULTS

The mean age and QRS duration were 60 years and 157 ms, respectively, and 13 (28.9%) were female. At a mean follow-up of 3 years, there were 22 (48.9%) "CRT responders" (≥15% reduction in LV end-systolic volume index [LVESVi]). Significant improvements were observed in LV ejection fraction (26.3% vs 34.3%) and LVESVi (87.7 vs 71.1 mL/m² ), as well as mitral regurgitation vena contracta width, MV tenting height and area, and end-systolic interpapillary muscle distance. Five-year actuarial survival was 87.5%. Multivariate regression analyses revealed the pre-CRT LVESVi (β = 0.52), and MV coaptation length (β = -0.34) and septolateral annular diameter (β = 0.25) as good correlates of follow-up LVESVi. Variables associated with CRT response were pre-CRT MV coaptation length (OR 1.75, 95% CI 1.0-3.1) and posterior leaflet tethering angle (OR 1.07, 95% CI 1.0-1.14), irrespective of baseline QRS morphology and duration (all P < .05).

CONCLUSIONS

Cardiac resynchronization therapy improves LV and MV geometry and function in half of patients with NICMP, which is paralleled by decreased mitral regurgitation severity. The extent of pre-CRT LV remodeling and MV tethering are associated with CRT response.

Predictors of residual mitral regurgitation after left ventricular assist device implantation

Patients with advanced heart failure often have functional mitral regurgitation. Left ventricular assist device implantation improves functional mitral regurgitation through left ventricular unloading. However, residual mitral regurgitation after left ventricular assist device implantation leads to adverse outcomes, and whether patients need concomitant mitral valve surgery is not fully elucidated. Therefore, this study aimed to elucidate the predictors of residual mitral regurgitation and to describe the temporal changes in residual mitral regurgitation. We retrospectively enrolled 15 patients with implantable continuous-flow left ventricular assist device, who had significant mitral regurgitation on echocardiography before left ventricular assist device implantation. Three patients had residual mitral regurgitation (mitral regurgitation color jet area/left atrial area >0.2) 1 month after left ventricular assist device implantation. We investigated factors associated with residual mitral regurgitation and compared patients with or without residual mitral regurgitation. On univariate analysis, mitral valve tethering area and mitral regurgitation vena contracta before left ventricular assist device implantation were significantly associated with residual mitral regurgitation (odds ratio, 1.03; p = 0.036 and odds ratio, 10.45; p = 0.0087). One month after left ventricular assist device implantation, the mean pulmonary capillary wedge pressure and pulmonary artery pressure were higher in patients with residual mitral regurgitation (pulmonary capillary wedge pressure: 11.3 ± 3.5 vs 6.4 ± 3.4 mmHg, p = 0.029 and pulmonary artery pressure: 21.3 ± 4.0 vs 15.9 ± 3.3 mmHg, p = 0.023). However, the mitral regurgitation grading and hemodynamics were not significantly different 6 months after left ventricular assist device implantation. The hospitalization-free survival was not significantly different between the two groups. Mitral valve tethering area and mitral regurgitation vena contracta were predictors of residual mitral regurgitation. Residual mitral regurgitation improved until 6 months after left ventricular assist device implantation and might not affect the prognosis.

Mitral Valve and Subvalvular Repair for Secondary Mitral Regurgitation: Rationale and Clinical Outcomes of the Papillary Muscle Sling

Secondary mitral regurgitation (MR) is a common finding in patients with dilated cardiomyopathy, and it is associated with poor outcomes. It is the result of incomplete systolic closure of the mitral valve (MV) as a consequence of left ventricular dilatation, papillary muscle displacement with impaired systolic shortening, and mitral leaflet tethering. MV surgery may be performed in cases of significant secondary MR despite guideline-directed medical therapy. However, MV repair, which is most commonly performed with an undersized ring annuloplasty, is associated with a 30-60% recurrence of moderate or greater MR at mid-term follow-up. To improve MV repair durability, several adjunctive subvalvular procedures have been proposed, one of which is the addition of papillary muscle approximation utilizing a papillary muscle sling. Recent studies comparing the outcomes of a conventional undersized ring annuloplasty with a MV repair utilizing a papillary muscle sling have reported a significant reduction in recurrent moderate or severe MR, greater left ventricular reverse remodeling, and improved MV apparatus geometry with the addition of the papillary muscle sling. We present a comprehensive review of the pathophysiology of secondary MR, and the rationale and clinical outcomes of MV repair with papillary muscle sling placement for the treatment of secondary MR.

Prediction of the ischemic origin of functional mitral regurgitation in patients with systolic heart failure through posterior mitral leaflet angle

BACKGROUND

Differentiating ischemic from non-ischemic functional mitral regurgitationý (FMR) in patients with cardiomyopathy is important in terms of the therapeutic decision-making and prognosis, but might be clinically challenging. In this study, the deformation of mitral valve (MV) indices in the prediction of the etiology of FMR was assessed using 2D transthoracic and tissue Doppler echocardiography.

METHODS

This case-control study was conducted from April 2015 to January 2016 in Imam Reza Hospital in Mashhad, Iran. The participants consisted of 40 patients with ischemic cardiomyopathy (ICM) and 22 with non-ischemic dilated cardiomyopathy (DCM) who referred to the heart failure clinic. Transthoracic echocardiography was performed using the conventional 2D and tissue Doppler imaging (TDI). MV tenting area (TA), coaptation distance (CD), anterior and posterior mitral leaflet angles (AMLA and PMLA), and regional systolic myocardial velocity (Sm) were measured.

RESULTS

There were no significant differences in echocardiographic indices between the two groups, besides Sm and PMLA which were significantly lower and higher, respectively, in ICM subjects in comparison with DCM patients (P = 0.002). PMLA ≥ 40 degrees and Sm ≤ 4 cm/second have a relatively high value for discriminating the ischemic from non-ischemic origin of functional MR in subjects with systolic heart failure (sensitivity: 80.0% and 70.0%, specificity: 73.0% and 77.3%; P = 0.001 and P < 0.001; respectively). Multivariable logistic regression identified PMLA and anterior Sm as major determinants for ischemic MR {Odds ratio (OR) [95% confidence interval (CI)] = 0.89 (0.82-0.96), P = 0.003, OR (95% CI) = 0.29 (0.14-0.60), P = 0.001, respectively}.

CONCLUSION

The present study showed that PMLA and Sm had an independent significant association with the mechanism of FMR. These findings are suggestive of the predictive role of mitral deformation echocardiographic indices in the determination of the etiology of FMR in systolic heart failure.

Effect of cardiac resynchronization therapy on mitral valve geometry: a novel aspect as "reversed mitral remodeling"

Amelioration of the valvular geometry is a possible mechanism for mitral regurgitation (MR) improvement in patients receiving cardiac resynchronization therapy (CRT). We aimed to establish the precise definition, incidence, and predictors of reversed mitral remodeling (RMR), as well as the association with MR improvement and short-term CRT outcome. Ninety-five CRT recipients were retrospectively evaluated for the end-point of "MR response" defined as the absolute reduction in regurgitant volume (RegV) at 6 months. To identify RMR, changes in mitral deformation indices were tested for correlation with MR response and further analyzed for functional and echocardiographic CRT outcomes. Overall, MR response was observed in 50 patients (53%). Among the echocardiographic indices, the change in tenting area (TA) had the highest correlation with the change in RegV (r = 0.653, p < 0.001). The mean TA significantly decreased in MR responders (4.15 ± 1.05 to 3.67 ± 1.01 cm² at 6 months, p < 0.001) and increased in non-responders (3.68 ± 1.04 to 3.98 ± 0.97 cm², p = 0.014). The absolute TA reduction was used to identify patients with RMR (47%) which was found to be associated with higher rates of functional improvement (p = 0.03) and volumetric CRT response (p = 0.036) compared to those without RMR. Non-ischemic etiology and the presence of LBBB independently predicted RMR at multivariate analysis. In conclusion, reduction in TA is a reliable index of RMR, which relates to MR response, and functional and echocardiographic improvement with CRT. LBBB and non-ischemic etiology are independent predictors of RMR.

Ischemic or Nonischemic Functional Mitral Regurgitation and Outcomes in Patients With Acute Decompensated Heart Failure With Preserved or Reduced Ejection Fraction

The aim of this study was to evaluate the association of functional mitral regurgitation (FMR), preserved or reduced ejection fraction (EF), and ischemic or nonischemic origin with outcomes in patients discharged alive after hospitalization for acute decompensated heart failure (HF). Of the 4,842 patients enrolled in the Acute Decompensated Heart Failure Syndromes (ATTEND) registry, 3,357 patients were evaluated to assess the association of FMR, preserved or reduced EF, and ischemic or nonischemic origin with the primary end point (all-cause death and readmission for HF after discharge). At the time of discharge, FMR was assessed semiquantitatively (classified as none, mild, or moderate to severe) by color Doppler analysis of the regurgitant jet area. According to multivariable analysis, in the ischemic group, either mild or moderate to severe FMR in patients with a preserved EF had a significantly higher risk of the primary end point than patients without FMR (hazard ratio [HR] 1.60; 95% confidence interval [CI] 1.12 to 2.29; p = 0.010 and HR 1.98; 95% CI 1.30 to 3.01; p = 0.001, respectively). In patients with reduced EF with an ischemic origin, only moderate to severe FMR was associated with a significantly higher risk of the primary end point (HR 1.67; 95% CI 1.11 to 2.50; p = 0.014). In the nonischemic group, there was no significant association between FMR and the primary end point in patients with either a preserved or reduced EF. In conclusion, among patients with acute decompensated HF with a preserved or reduced EF, the association of FMR with adverse outcomes may differ between patients who had an ischemic or nonischemic origin of HF.

Determinants of Atrial Electromechanical Delay in Patients with Functional Mitral Regurgitation and Non-ischemic Dilated Cardiomyopathy

Introduction: Atrial conduction time has important hemodynamic effects on ventricular filling and is accepted as a predictor of atrial fibrillation. In this study we assessed atrial conduction time in patients with non ischemic dilated cardiomyopathy (NIDCMP) and functional mitral regurgitation (MR) and aimed to determine factors predicting atrial conduction time prolongation.

Methods: Sixty five patients with non ischemic dilated cardiomyopathy who have moderate to severe MR and 60 control subjects were included in the study. In addition to conventional echocardiographic measures used to asses left ventricle and MR, atrial electromechanical coupling (time interval from the onset of P wave on surface electrocardiogram [ECG] to the beginning of A wave interval with tissue Doppler echocardiography [PA]), intra- and interatrial electromechanical delay (intra and inter AEMD) were measured.

Results: The correlations between inter AEMD and left atrial (LA) size, MR volume, isovolumetric relaxation time (IVRT), deceleration time (DT), systolic pulmonary artery pressure (PAPs), E/A ratio and E/e’ were very poor. Similarly, intra AEMD was not correlated to LA size , MR volume, IVRT, DT, PAPs, E/A ratio and E/e’. However, both inter AEMD and intra AEMD had good correlation with left ventricular mass index, tenting area (TA), tenting distance (TD), coaptation septal distance (CSD), sphericity index (SI).

Conclusion: Prolongation of inter and intra AEMDs were found to be well correlated with parameters reflecting left ventricular and mitral annular remodeling.

Left ventricular sphericity index predicts systolic dysfunction in rats with experimental aortic regurgitation

Although an increased left ventricular (LV) diastolic diameter (DD) and a decreased ejection fraction have been used as markers for the surgical replacement of an insufficient aortic valve, these signals may be observed when irreversible myocardium damage has already occurred. The aim of this study was to determine whether change in LV geometry predicts systolic dysfunction in experimental aortic regurgitation. Male Wistar rats underwent surgical acute aorta regurgitation (aorta regurgitation group; n = 23) or a sham operation (sham group; n = 12). After the procedure, serial transthoracic echocardiograms were performed at 1, 4, 8, and 16 wk. At the end of protocol, the LV, lungs, and liver were dissected and weighed. During the follow-up, no animal developed overt heart failure. There was a correlation between the LV sphericity index and reduced fractional shortening ( P < 0.001) over time. A multiple regression model showed that the LVDD-sphericity index association at 8 wk was a better predictor of decreased fractional shortening at week 16 ( R2 = 0.50; P < 0.001) than was the LVDD alone ( R2 = 0.39; P = 0.001). LV geometry associated with increased LVDD improved the prediction of systolic dysfunction in experimental aortic regurgitation.

Incremental value of global systolic dyssynchrony in determining the occurrence of functional mitral regurgitation in patients with left ventricular systolic dysfunction

AIMS

The aim of this study was to assess the contribution of left ventricular (LV) systolic dyssynchrony to functional mitral regurgitation (MR).

METHODS AND RESULTS

Patients (n = 136) with LV systolic dysfunction (ejection fraction <50%) and at least mild MR were prospectively recruited. The effective regurgitant orifice area (EROA) was assessed by the proximal isovelocity surface area method. Left ventricular global systolic dyssynchrony [the maximal difference in time to peak systolic velocity among the 12 LV segments (Ts-Dif)] and regional systolic dyssynchrony (the delay between the anterolateral and posteromedial papillary muscle attaching sites) were assessed by tissue Doppler imaging. Left ventricular global and regional remodelling, systolic function, indices of mitral valvular and annular deformation were also measured. The size of the EROA correlated with the degrees of mitral deformation, LV remodelling, systolic function, and systolic dyssynchrony. By multivariate logistic regression analysis, the mitral valve tenting area (OR = 1.020, P < 0.001) and the Ts-Dif (OR = 1.011, P = 0.034) were independent determinants of significant functional MR (defined by EROA ≥20 mm(2)). From the receiver-operating characteristic curve, the tenting area of 2.7 cm(2) (sensitivity 83%, specificity 82%, AUC 0.86, P < 0.001) and the Ts-Dif of 85 ms (sensitivity 66%, specificity 72%, AUC 0.74, P < 0.001) were associated with significant functional MR. The assessment of Ts-Dif showed an incremental value over the mitral valve tenting area for determining functional MR (χ(2) = 53.92 vs.49.11, P = 0.028).

CONCLUSION

This cross-sectional study showed that LV global, but not regional systolic dyssynchrony, is a determinant of significant functional MR in patients with LV systolic dysfunction, and is incremental to the tenting area that is otherwise the strongest factor for mitral valve deformation.