Atrioventricular reverse remodeling after valve repair for chronic severe mitral regurgitation: 1-year follow-up

The Role of Global Longitudinal Strain in Predicting Left Ventricular Reverse Remodeling After Mitral Valve Replacement Surgery in Patients With Primary Mitral Regurgitation

OBJECTIVES

This study aimed to identify the utility of global longitudinal strain (GLS) as a reliable parameter that can accurately forecast left ventricle reverse remodeling (LVRR) in patients undergoing valve replacement surgery for severe chronic primary mitral regurgitation (MR), thereby aiding in assessing mortality and morbidity risk.

METHODS

This retrospective observational study involved severe primary MR patients who underwent valve replacement surgery between 2018 and 2023. Pre- and postsurgery echocardiography data were collected, with GLS measurements utilized to assess left ventricular function. Various echocardiography parameters, including MR severity and LV dimensions, were analyzed. Bivariate and multivariate analyses were performed to explore relationships between GLS and LVRR.

RESULTS

This study enrolled 103 patients (54.4% male; mean age 45.4 ± 13.6 years). Statistical analyses revealed GLS to be an independent predictor of LVRR, with a threshold of -16.25% showing 89% sensitivity and 50% specificity. Each 1% increase in GLS corresponded to a 1.14-fold (odds ratio [OR]: 1.14; 95% confidence interval [CI]: 1.01-1.31; p < 0.05) increased likelihood of LVRR.

CONCLUSION

These findings highlight GLS's potential as a prognostic marker for postsurgical outcomes in severe MR patients.

The Clinical Applications of Left Atrial Strain: A Comprehensive Review

Left atrial (LA) strain imaging, which measures the deformation of the LA using speckle-tracing echocardiography (STE), has emerged recently as an exciting tool to help provide diagnostic and prognostic information for patients with a broad range of cardiovascular (CV) pathologies. Perhaps due to the LA's relatively thin-walled architecture compared with the more muscular structure of the left ventricle (LV), functional changes in the left atrium often precede changes in the LV, making LA strain (LAS) an earlier marker for underlying pathology than many conventional echocardiographic parameters. LAS imaging is typically divided into three phases according to the stage of the cardiac cycle: reservoir strain, which is characterized by LA filling during systole; conduit strain, which describes LA deformation during passive LV filling; and booster strain, which provides information on the LA atrium during LA systole in late ventricular diastole. While additional large-population studies are still needed to further solidify the role of LAS in routine clinical practice, this review will discuss the current evidence of its use in different pathologies and explore the possibilities of its applications in the future.

Clinical Utility of Strain Imaging in Assessment of Myocardial Fibrosis

Myocardial fibrosis (MF) is a non-reversible process that occurs following acute or chronic myocardial damage. MF worsens myocardial deformation, remodels the heart and raises myocardial stiffness, and is a crucial pathological manifestation in patients with end-stage cardiovascular diseases and closely related to cardiac adverse events. Therefore, early quantitative analysis of MF plays an important role in risk stratification, clinical decision, and improvement in prognosis. With the advent and development of strain imaging modalities in recent years, MF may be detected early in cardiovascular diseases. This review summarizes the clinical usefulness of strain imaging techniques in the non-invasive assessment of MF.

Stage-based approach to predict left ventricular reverse remodeling after mitral repair

Background

Although predictors of reverse left ventricular (LV) remodeling postmitral valve repair are critical for guiding perioperative decision‐making, there remains a paucity of randomized, prospective data to support the criteria that potential predictor variables must meet.

Methods and Results

The CAMRA CardioLink‐2 randomized trial allocated 104 patients to either leaflet resection or preservation strategies for mitral repair. The correlation of indexed left ventricular end‐systolic volume (LVESVI), indexed left ventricular end‐diastolic volume (LVEDVI), and left ventricular ejection fraction (LVEF) were tested with univariate analysis and subsequently with multivariate analysis to determine independent predictors of reverse remodeling at discharge and at 12 months postoperatively. At discharge, both LVESVI and LVEDVI were independently associated with their preoperative values (p < .001 for both) and LVEF by preoperative LVESVI (p < .001). Mitral ring size was favorably associated with the change in LVESVI (p < .05) and LVEF (p < .01) from predischarge to 12 months, while the mean mitral valve gradient after repair was adversely associated with the change in LVESVI (p < .05) and LVEDVI (p < .05). No significant associations were found between reverse remodeling and coaptation height nor mitral repair technique.

Conclusions

Beyond confirming the lack of impact of mitral repair technique on reverse remodeling, this investigation suggests that recommending surgery before significant LV dilatation or dysfunction, as well as higher postoperative mitral valve hemodynamic performance, may enhance remodeling capacity following mitral repair.

Cardiac remodelling - Part 2: Clinical, imaging and laboratory findings. A review from the Study Group on Biomarkers of the Heart Failure Association of the European Society of Cardiology

In patients with heart failure, the beneficial effects of drug and device therapies counteract to some extent ongoing cardiac damage. According to the net balance between these two factors, cardiac geometry and function may improve (reverse remodelling, RR) and even completely normalize (remission), or vice versa progressively deteriorate (adverse remodelling, AR). RR or remission predict a better prognosis, while AR has been associated with worsening clinical status and outcomes. The remodelling process ultimately involves all cardiac chambers, but has been traditionally evaluated in terms of left ventricular volumes and ejection fraction. This is the second part of a review paper by the Study Group on Biomarkers of the Heart Failure Association of the European Society of Cardiology dedicated to ventricular remodelling. This document examines the proposed criteria to diagnose RR and AR, their prevalence and prognostic value, and the variables predicting remodelling in patients managed according to current guidelines. Much attention will be devoted to RR in patients with heart failure with reduced ejection fraction because most studies on cardiac remodelling focused on this setting.

Detection of myocardial fibrosis by speckle-tracking echocardiography: from prediction to clinical applications

Myocardial fibrosis (MF) represents the underlying pathologic condition of many cardiac disease, leading to cardiac dysfunction and heart failure (HF). Biopsy studies have shown the presence of MF in patients with decompensating HF despite apparently normal cardiac function. In fact, basic indices of left ventricular (LV) function, such as LV ejection fraction (EF), fail to recognize subtle LV dysfunction caused by MF. Cardiac magnetic resonance (CMR) with late gadolinium enhancement (LGE) is currently recognized as the gold standard imaging investigation for the detection of focal and diffuse cardiac chambers MF; however, its use is limited by its availability and the use of contrast agents, while echocardiography remains the first level cardiac imaging technique due to its low cost, portability and high accessibility. Advanced echocardiographic techniques, above all speckle-tracking echocardiography (STE), have demonstrated reliability for early detection of structural myocardial abnormalities and for the prediction of prognosis in acute and chronic HF. Myocardial strain of both ventricles and also left atrium has been shown to correlate with the degree of MF, providing useful prognostic information in several diseases, such as HF, cardiomyopathies and valvular heart disease. This paper aims to provide an overview of the pathophysiology of MF and the clinical application of STE for the prediction of left and right heart chambers MF in HF patients.

Changes in renin-angiotensin-aldosterone system during cardiac remodeling after mitral valvuloplasty in dogs

BACKGROUND

Information regarding changes in renin-angiotensin-aldosterone system (RAAS) during cardiac remodeling after mitral valvuloplasty (MVP) in dogs remains lacking.

HYPOTHESIS/OBJECTIVES

To assess the longitudinal effects of MVP on circulating RAAS activity.

ANIMALS

Eight client-owned dogs receiving MVP for myxomatous mitral valve disease (MMVD).

METHODS

This is a cohort study. Plasma renin activity (PRA), angiotensin II (AT2), aldosterone (PAC), blood urea nitrogen (BUN), and creatinine concentrations, were measured in these dogs before (baseline) and at 3 consecutive monthly follow-ups (Post-1M, Post-2M, Post-3M). Echocardiography was concomitantly used to assess the process of cardiac recovery after MVP.

RESULTS

The echocardiography revealed a significant decrease in LVIDDN, LA/Ao, FS, E velocity, E/A, E' sep, S' lat, E' lat, and A' lat after MVP compared with baseline (P < .05). There was a significant reduction in the PRA (2.45, 3.05, 2.74 vs 8.8 ng/mL/h; P = .002), AT2 (466, 315, 235 vs 1200 pg/mL; P = .009), and PAC (39.88, 47, 54.62 vs 179.5 pg/mL; P = .01), respectively at Post-1M, Post-2M, Post-3M compared to the baseline. Additionally, BUN and creatinine concentrations decreased from Post-1M. The RAAS variables showed significant, weak to moderate, relationship with selected echocardiographic variables.

CONCLUSIONS AND CLINICAL IMPORTANCE

Mitral valvuloplasty contributes to decreased RAAS activity in MMVD dogs, which paralleled the process of cardiac reverse remodeling up to Post-3M. This information facilitates formulating strategies to optimize clinical outcomes for dogs after MVP.

Mitral repair with leaflet preservation versus leaflet resection and ventricular reverse remodeling from a randomized trial

OBJECTIVES

In the Canadian Mitral Research Alliance (CAMRA) Trial CardioLink-2 leaflet resection versus preservation techniques for posterior leaflet prolapse was investigated and no difference was shown in their effect on mean mitral gradient at peak exercise at 12 months postoperatively. The purpose of this subanalysis was to evaluate the effect of the 2 strategies on left ventricular (LV) reverse remodeling after repair.

METHODS

A total of 104 patients were randomized to either a leaflet resection or leaflet preservation strategy. Echocardiograms, performed at baseline (preoperative), predischarge, and 12 months postoperatively, were analyzed in a blinded fashion at a core laboratory.

RESULTS

All patients underwent successful mitral repair. At discharge, 3 patients showed moderate mitral regurgitation, whereas the remainder showed mild or less regurgitation. Compared with the baseline echocardiogram, the indexed end diastolic volume was reduced at the discharge echocardiogram (P < .0001) and was further reduced at the 12-month echocardiogram (P = .01). In contrast, the indexed end systolic volume did not significantly change from baseline assessed at the predischarge echocardiogram (P = .32) but improved at 12 months postoperatively (P < .0001), resulting in a corresponding improvement in ejection fraction at 12 months (P < .0001). The type of mitral repair strategy had no significant effect on LV reverse remodeling trends.

CONCLUSIONS

The mitral repair strategies used did not influence postoperative LV reverse remodeling, which occurred in stages. Although LV end diastolic dimensions recovered before discharge, improvements in LV end systolic dimension were evident 12 months after repair.

2D/3D echocardiographic determinants of left ventricular reverse remodelling after MitraClip implantation

AIMS

The aim of this study was to describe incidence and determinants of left ventricular reverse remodelling (r-LVR) at 6 months follow-up after MitraClip implantation in patients with secondary severe mitral regurgitation (MR) and reduced left ventricular ejection fraction (LVEF).

METHODS AND RESULTS

Forty-five patients, undergoing MitralClip implantation with low ejection fraction and high surgical risk were enrolled in this study. Three of them died before the scheduled 6 months follow-up period and one patient had cardiac surgery due to MitraClip detachment. All patients underwent transthoracic 2D and 3D echocardiography before and 6 months after the procedure. A significant MR severity reduction and an improvement in New York Heart Association (NYHA) class were detected in all patients. The study population was divided in two groups according to the presence of r-LVR (51%, n = 23 patients) or not (non-rLVR group, 18 patients). Non-significant differences in MR aetiology and number of clips implanted were found. Left ventricular reverse remodelling patients showed significant lower values of logistic EuroSCORE and STS score, left ventricular end-diastolic volume index (LVEDV/i), right ventricular end systolic area, and pulmonary artery systolic pressure (PASp) at baseline evaluation. At multivariable analysis, baseline PASp value resulted to be the only independent predictor of r-LVR [odds ratio 95% confidence interval 0.94 (0.89-0.99), P = 0.021]. In r-LVR patients, a significant improvement in LVEF and global longitudinal strain and a reduction in left atrial volume index were detected after 6 months, whereas in non-rLVR subgroup a significant increase in both LVEDV/i and left ventricular end-systolic volume index was observed at follow-up.

CONCLUSION

Even if a reduction of MR was detected in all patients after MitralClip implant, our findings suggest that end-stage patients presenting with higher left ventricular volumes, logistic scores, and PASp may not benefit from the procedure at longer follow-up in terms of left ventricular function.

The role of the left atrial function in the surgical management of aortic and mitral valve disease

The right management of both mitral and aortic disease can be challenging, especially in asymptomatic patients. The current guidelines recommend valve repair or replacement when symptoms arise or when there is an evident left ventricular dysfunction. However, deciding the optimal surgical timing can be very difficult, since the line between the absence of symptoms and being minimally symptomatic, especially in the elderly, is blurred. Another relevant issue regards the second surgical criterion: operating on a patient with a reduced left ventricular ejection fraction or with a dilated left ventricle might jeopardize the possibility of a fully reverse remodeling of the heart after surgery. In this scenario, the left atrium might play an important role. In particular, left atrial deformation might be a very useful tool to detect early ultrastructural alterations, and help or support guiding a patient-tailored treatment at an early stage, optimizing the outcome in the long term.

The Role of Arterial Hypertension in Mitral Valve Regurgitation

PURPOSE OF REVIEW

To review medical literature for evidence of association between hypertension and mitral regurgitation (MR) and summarize potential favorable effects of antihypertensive drugs on MR natural history and treatment.

RECENT FINDINGS

Hypertension and MR are common diseases affecting a large proportion of the general population. Contemporary evidence suggests that hypertension may worsen the progression and prognosis of MR through augmented mechanical stress and increased regurgitation volume. Renin-angiotensin axis inhibitors, beta-blockers, and vasodilators have been tested in order to prevent or decrease primary or secondary MR. Although antihypertensive agents may improve hemodynamic parameters and left ventricular remodeling in primary MR, there is no strong evidence of benefit on clinical outcomes. On the other hand, a beneficial effect of these drugs on secondary MR is better established. Moreover, there are no studies evaluating a possible benefit of lower blood pressure targets in MR. Randomized controlled trials are warranted to elucidate the precise role of antihypertensive therapy on treatment of MR.

Mitral regurgitation severity correlates with symptoms and extent of left atrial dysfunction: Effect of mitral valve repair

PURPOSE

We aimed to assess the relationship between mitral regurgitation (MR) severity, symptoms, and left atrial (LA) structure and function, before and after mitral valve repair (MVR).

METHODS

Global peak atrial longitudinal strain (PALS) was evaluated in 37 patients with severe symptomatic MR and preserved left ventricular (LV) ejection fraction (60.4% ± 4.6%) before and 3 months after MVR and was compared with values from 30 age- and gender-matched controls.

RESULTS

Before surgery, PALS was worse in patients than in controls and indexed LA volume was greater (P < .0001 for both). After MVR, PALS deteriorated further and LA volume decreased (P = .001 and P = .05, respectively) as did LV ejection fraction, longitudinal strain (P = .05 and P < .001, respectively), and LV mass (P < .0001). Before surgery, LA volume correlated modestly with LV end-diastolic volume (R = 0.51; P = .01); effective regurgitant orifice area (EROA) correlated with PALS (R = -0.69, P < .001) and with LV longitudinal strain (R = 0.54, P = .01), and New York Heart Association class correlated with PALS (R = -0.69, P < .001), EROA (R = 0.69, P < .001), and LA volume (R = 0.51, P = .04). LA volume was the strongest predictor of global PALS reduction (P < .001), whereas global PALS was the main predictor of postoperative atrial fibrillation (AF) (P < .001).

CONCLUSIONS

In patients with severe MR, EROA correlate with symptoms and LA PALS, which itself predicts the occurrence of postoperative AF. Strain values were superior to 2D data for the prediction of postoperative AF.

Should pre-operative left atrial volume receive more consideration in patients with degenerative mitral valve disease undergoing mitral valve surgery?

BACKGROUND

Severe primary mitral regurgitation (MR) carries a significant incidence of mortality and morbidity. Though a number of prognostic factors have been identified, the best timing for mitral valve repair is still debated. We assessed the role of Left Atrial Volume Indexed (LAVI) as predictor of adverse events after mitral valve surgery.

METHODS

134 patients with severe MR were studied with a follow-up of 42±16months. Endpoints were Post-Operative Atrial Fibrillation (POAF), atrial and ventricular remodeling (LARR/LVRR) and correlation with outcome. POAF was defined as AF occurring within 2weeks and late AF (LAF) more than 2weeks after surgery. LARR was defined as LAVI reduction ≥15% and LVRR as any reduction of ventricular mass after surgery.

RESULTS

Forty-one patients experienced POAF, 26 had LAF. Pre-operative LAVI was an independent risk factor for POAF (OR 1.03, CI [1.00-1.06], p=0.01), LAF (OR 1.03, CI [1.00-1.06], p=0.02), LARR and LVRR (OR 1.04, CI [1.01-1.07], p=0.002, respectively). LARR was found in 75 patients, while LVRR in 111. Patients with heart remodeling had less incidence of LAF and cardiac adverse events, better diastolic function and improved their NYHA class after surgery.

CONCLUSIONS

LAVI should be given more weight into decision making for patients with MR as it predicts POAF and LAF and reverse atrial and ventricular remodeling, both associated to long-term outcome.

Time course of left atrial reverse remodelling after mitral valve surgery and the impact of left ventricular global longitudinal strain in patients with chronic severe mitral regurgitation

OBJECTIVES

We aimed to investigate the time course of left atrial (LA) reverse remodelling (LARR) after mitral valve (MV) surgery in patients with chronic severe mitral regurgitation (MR) and examine the impact of left ventricular (LV) mechanical function on LARR.

METHODS

A total of 140 patients (73 males, age 54 ± 16 years) with chronic severe MR undergoing MV surgery were analysed. All patients underwent two-dimensional, Doppler and speckle-tracking echocardiography before and after surgery (1 week, 6 months and 12 months).

RESULTS

There was a significant decrease in LA volume from 137.8 ± 85.5 to 89.7 ± 54.6 ml (-32.1 ± 16.7%, P < 0.001) at 1 week after surgery. LA volume further decreased to 77.4 ± 52.4 ml (-9.9 ± 13.4%, P < 0.001) at 6 months but increased to 79.7 ± 62.4 ml (3.6 ± 11.9%, P = 0.002) at 12 months after surgery. Patients with good LARR (a reduction of ≥25% in LA volume) showed lower LV global longitudinal strain (LV-GLS) than those with poor LARR (P = 0.032). In simple correlation, age (r = 0.19, P = 0.026), preoperative LA volume (r = -0.28, P = 0.001) and preoperative LV-GLS (r = 0.28, P = 0.001) showed significant correlations with the % change in LA volume, whereas no correlations were observed with preoperative LV ejection fraction, global circumferential and radial strain. In multivariate analyses, preoperative LV-GLS (β = 0.24, P = 0.014) was an independent determinant for early LARR along with age and preoperative LA volume.

CONCLUSIONS

The majority of LARR after MV surgery occurred during the early postoperative period. LV-GLS, age and LA volume at surgery determined the degree of early LARR after MV surgery in patients with chronic severe MR.

Preoperative left ventricular ejection fraction and left atrium reverse remodeling after mitral regurgitation surgery

Background

Left atrium enlargement has been associated with cardiac events in patients with mitral regurgitation (MR). Left atrium reverse remodeling (LARR) occur after surgical correction of MR, but the preoperative predictors of this phenomenon are not well known. It is therefore important to identify preoperative predictors for postoperative LARR.

Methods

We enrolled 62 patients with chronic severe MR (prolapse or flail leaflet) who underwent successful mitral valve surgery (repair or replacement); all with pre- and postoperative echocardiography. LARR was defined as a reduction in left atrium volume index (LAVI) of ≥25%. Stepwise multiple regression analysis was used to identify independent predictors of LARR.

Results

LARR occurred in 46 patients (74.2%), with the mean LAVI decreasing from 85.5 mL/m² to 49.7 mL/m² (p <0.001). These patients had a smaller preoperative left ventricular systolic volume (p =0.022) and a higher left ventricular ejection fraction (LVEF) (p =0.034). LVEF was identified as the only preoperative variable significantly associated with LARR (odds ratio, 1.086; 95% confidence interval, 1.002–1.178). A LVEF cutoff value of 63.5% identified patients with LARR of ≥25% with a sensitivity of 71.7% and a specificity of 56.3%.

Conclusions

LARR occurs frequently after mitral valve surgery and is associated with preoperative LVEF higher than 63.5%.