Left atrial strain as a pre-operative prognostic marker for patients with severe mitral regurgitation

Left Atrium: A New Prognostic Marker and Therapeutic Target in Secondary Mitral Regurgitation?

Mitral regurgitation (MR) is one of the most common valvular abnormalities worldwide and can be subdivided into primary and secondary causes. Atrial MR consists of a novel type of secondary MR (SMR), most often observed in patients with AF and heart failure with preserved ejection fraction. The main pathophysiological mechanism of atrial MR is mitral valve annular dilatation. Recently published studies have highlighted the clinical significance of left atrium (LA) evaluation in the early diagnosis and prognosis of patients with primary MR. However, there are little data regarding the role of the LA in SMR. The present literature review aims to elucidate the use of the echocardiographic parameters regarding LA evaluation in the prognosis prediction and therapeutic strategy of patients with SMR.

Incremental diagnostic and prognostic utility of left atrial deformation in heart failure using speckle tracking echocardiography

Left atrium (LA) is a very important component of cardiovascular performance. The assessment of LA function has gathered the interest with expanding research supporting the utility as a biomarker for outcomes in heart failure (HF). Echocardiography is the main imaging modality which helps in a qualitative and quantitative assessment of the LA size and function. Recent advances in probe technology and software analysis have provided a better understanding of LA anatomy, physiology, pathology, and function. A variety of parameters have been defined as markers of LA function but there is no single parameter that best defines LA function. Speckle tracking echocardiography-derived analysis of LA deformation provides a window on all phases of LA function (reservoir, conduit, and booster pump). There is accumulative published data that supported the diagnostic and prognostic values of LA deformation integration during echo assessment of LA in HF. This review article summarized the clinical utility of LA deformation that may help in prediction, diagnosis, categorization, risk stratification, and guiding the proper selection of therapy in HF patients in daily practice.

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.

Left ventricular fibrosis as a main determinant of filling pressures and left atrial function in advanced heart failure

AIMS

Advanced heart failure (AdHF) is characterized by variable degrees of left ventricular (LV) dysfunction, myocardial fibrosis, and raised filling pressures which lead to left atrial (LA) dilatation and cavity dysfunction. This study investigated the relationship between LA peak atrial longitudinal strain (PALS), assessed by speckle-tracking echocardiography (STE), and invasive measures of LV filling pressures and fibrosis in a group of AdHF patients undergoing heart transplantation (HTX).

METHODS AND RESULTS

We consecutively enrolled patients with AdHF who underwent HTX at our Department. Demographic and basic echocardiographic data were registered, then invasive intracardiac pressures were obtained from right heart catheterization, and STE was also performed. After HTX, biopsy specimens from explanted hearts were collected to quantify the degree of LV myocardial fibrosis. Sixty-four patients were included in the study (mean age 62.5 ± 11 years, 42% female). The mean LV ejection fraction (LVEF) was 26.7 ± 6.1%, global PALS was 9.65 ± 4.5%, and mean pulmonary capillary wedge pressure (PCWP) was 18.8 ± 4.8 mmHg. Seventy-three % of patients proved to have severe LV fibrosis. Global PALS was inversely correlated with PCWP (R = -0.83; P < 0.0001) and with LV fibrosis severity (R = -0.78; P < 0.0001) but did not correlate with LVEF (R = 0.15; P = 0.2). Among echocardiographic indices of LV filling pressures, global PALS proved the strongest [area under the curve 0.955 (95% confidence interval 0.87-0.99)] predictor of raised (>18 mmHg) PCWP.

CONCLUSION

In patients with AdHF, reduced global PALS strongly correlated with the invasively assessed LV filling pressure and degree of LV fibrosis. Such relationship could be used as non-invasive indicator for optimum patient stratification for therapeutic strategies.

Prognostic Implications of Left Atrial Strain in Bicuspid Aortic Valve With Chronic Aortic Regurgitation

BACKGROUND

Left atrial reservoir strain (LARS) is a novel imaging biomarker of left ventricular diastolic dysfunction. This study aimed to examine the prognostic implications of LARS in patients with bicuspid aortic valve and significant (moderate-severe to severe) aortic regurgitation.

METHODS AND RESULTS

A total of 220 patients with bicuspid aortic valve and significant aortic regurgitation were prospectively enrolled in our study. LARS and left ventricular global longitudinal strain were derived from speckle-tracking echocardiography. The end point was a composite of all-cause mortality, heart failure hospitalization, and aortic valve repair or replacement. The threshold value of LARS <24% was used to identify impaired left atrial mechanics based on prior results. During a median follow-up of 364 (interquartile range, 294-752) days, 46 patients (20.9%) reached the composite end points. On multivariable Cox analysis, impaired LARS (adjusted hazard ratio, 2.08 [95% CI, 1.05-4.11]; P=0.036) was a statistically significant predictor of composite end points after adjustment for other statistically significant predictors. Finally, adding impaired LARS to other statistically significant predictors (New York Heart Association functional class and left ventricular global longitudinal strain) significantly improved the global χ2 (from 32.19 to 36.56; P=0.037) and reclassification (continuous net reclassification index=0.55; P<0.001) of the prediction model.

CONCLUSIONS

In patients with bicuspid aortic valve and significant aortic regurgitation, the impairment of LARS is a strong independent prognostic predictor and confers incremental prognostic utility over clinical and other echocardiographic parameters. These findings suggest that LARS could be considered in risk stratification for such populations.

Myocardial work and left heart deformation parameters across primary mitral regurgitation severity

AIMS

Myocardial work (MW) estimation by pressure-strain loops using speckle tracking echocardiography (STE) has shown to evaluate left ventricular (LV) contraction overcoming the load-dependency limit of LV global longitudinal strain (GLS). This has proved useful in hemodynamic variation settings e.g. heart failure and valvular heart disease. However, the variation of MW and strain parameters across different stages of primary mitral regurgitation (MR) and its impact on symptoms, which was the aim of our study, has never been investigated.

METHODS AND RESULTS

Consecutive patients with mild, moderate and severe MR were prospectively enrolled. Exclusion criteria were: chronic atrial fibrillation, valvular heart prosthesis, previous cardiac surgery. Clinical evaluation, blood sample tests, ECG and echocardiography with STE and MW measurement were performed. Patients were then divided into groups according to MR severity. Differences among the groups and predictors of symptoms (as NYHA class≥2) were explored as study endpoints. Overall, 180 patients were enrolled (60 mild,60 moderate,60 severe MR). LV GLS and global peak atrial longitudinal strain (PALS) reduced according to MR severity. Global constructive work (GCW) and global wasted work (GWW) significantly improved, while global work efficiency (GWE) reduced, in patients with moderate and severe MR. Among echocardiographic parameters, global PALS emerged as the best predictor of NYHA class (p < 0.001;area under curve,AUC = 0.7).

CONCLUSIONS

MW parameters accurately describe the pathophysiology of MR, with initial attempt of LV increased contractility to compensate volume overload parallel to the disease progress, although with low efficacy, while global PALS is the most associated with the burden of MR symptoms.

Left atrial and left ventricular strain dynamics with echocardiography in asymptomatic children with mitral regurgitation

Left atrial (LA) dilatation is a strong predictor of cardiovascular morbidity and mortality. Strain parameters evaluating LA functions have gained importance in assessing cardiovascular health. This study aimed to investigate the relationship between LA and left ventricular (LV) strain, using speckle-tracking echocardiography, and assess the impact of vena contracta on LV functioning in asymptomatic children with mitral regurgitation. We evaluated 45 asymptomatic mitral regurgitation patients, categorized as mild, moderate, and severe. LV strain was significantly lower in the moderate group (-17.8 ± 3.7%) and further reduced in the severe group (16 ± 2.1%) compared to the reference group (20.5 ± 6.2%). Conversely, LA reservoir strain was higher in the severe and moderate groups (38 ± 12.9% and 40.7 ± 9.5%, respectively) compared to the controls (31.3 ± 7.5%; p < 0.0001). The severe group also displayed a milder depression of contraction (12.2%) compared to the moderate group (13 ± 7.2%). In the moderate and severe groups, LV strain correlated significantly with vena contracta (r=-0.858; p = 0.04), with vena contracta emerging as the only independent predictor for LV longitudinal strain. ROC curve analysis indicated a cut-off value > 5.65 mm for vena contracta, which had a positive predictive value of 75% for predicting LV function impairment. In conclusion, this study emphasizes the significance of assessing LA and ventricular strain in asymptomatic children with mitral regurgitation. Furthermore, vena contracta with diameters greater than 5.6 mm may alert clinicians to the possibility of LV function impairment. These findings offer valuable insights for the follow-up and management of paediatric patients with mitral regurgitation, enabling early detection of potential complications and improved patient outcomes.

Left atrial strain analysis in the realm of pediatric cardiology: Advantages and implications

BACKGROUND

Left atrial (LA) strain analysis has emerged as a noninvasive technique for assessing LA function and early detection of myocardial deformation. Recently, its application has also shown promise in the pediatric population, spanning diverse cardiac conditions that demand accurate and sensitive diagnostic measures.

OBJECTIVE

This research article endeavors to explore the role of LA strain parameters and contribute to the growing body of knowledge in pediatric cardiology, paving the way for more effective and tailored approaches to patient care.

METHODS

A comprehensive literature review was conducted to gather evidence from studies using echocardiographic strain imaging techniques across pediatric populations.

RESULTS

LA strain parameters exhibited greater sensitivity than conventional atrial function indicators, with early detection of diastolic dysfunction and LA remodeling in pediatric cardiomyopathy, children with multisystem inflammatory syndrome, rheumatic heart disease, as well as childhood renal insufficiency and obesity offering prognostic relevance as potential markers in these pediatric subpopulations. However, there remains a paucity of evidence concerning pediatric mitral valve pathology, justifying further exploration.

CONCLUSION

LA strain analysis carries crucial clinical and prognostic implications in pediatric cardiac conditions, with reliable accuracy and sensitivity to early functional changes.

Left Atrial Stiffness Index as a Predictor of Effort Intolerance and Hemodynamics Evaluated by Invasive Exercise Stress Testing in Degenerative Mitral Regurgitation

In patients with degenerative mitral regurgitation (DMR), peak oxygen consumption is the significant prognostic factor, and exercise intolerance has been considered a trigger for surgical intervention. The significant mitral regurgitation (MR) induces left atrial (LA) remodeling, but the significance of LA stiffness calculated by the ratio of E/e' to LA reservoir strain in degenerative MR has not been elucidated. A total of 30 patients with asymptomatic or minimally symptomatic grade ≥III + DMR underwent the cardiopulmonary exercising test simultaneously with invasive hemodynamic assessment. LA stiffness index significantly correlated with exercise hemodynamic deterioration, including pulmonary arterial wedge pressure (r = 0.71, p <0.01), systolic pulmonary arterial pressure at peak exercise (r = 0.73, p <0.01), and pulmonary circulatory reserve (mean pulmonary arterial pressure/cardiac output slope, r = 0.45, p = 0.012). Multiple linear regression analysis revealed that the higher LA stiffness index was significantly associated with decreased percent predicted peak oxygen consumption (per 0.1 increase, β -4.0, 95% confidence interval -6.9 to -1.3, p <0.01) independently of MR deterioration during exercise. In conclusion, increased LA stiffness was associated with exercise intolerance through hemodynamic deterioration during exercise in patients with asymptomatic or minimally symptomatic severe DMR.

Position Statement on the Use of Myocardial Strain in Cardiology Routines by the Brazilian Society of Cardiology's Department Of Cardiovascular Imaging - 2023

Central Illustration : Position Statement on the Use of Myocardial Strain in Cardiology Routines by the Brazilian Society of Cardiology's Department Of Cardiovascular Imaging - 2023 Proposal for including strain in the integrated diastolic function assessment algorithm, adapted from Nagueh et al.67 Am: mitral A-wave duration; Ap: reverse pulmonary A-wave duration; DD: diastolic dysfunction; LA: left atrium; LASr: LA strain reserve; LVGLS: left ventricular global longitudinal strain; TI: tricuspid insufficiency. Confirm concentric remodeling with LVGLS. In LVEF, mitral E wave deceleration time < 160 ms and pulmonary S-wave < D-wave are also parameters of increased filling pressure. This algorithm does not apply to patients with atrial fibrillation (AF), mitral annulus calcification, > mild mitral valve disease, left bundle branch block, paced rhythm, prosthetic valves, or severe primary pulmonary hypertension.

Effects of an Impaired Fasting Glucose on the Left Atrial Strain Evaluated by Speckle Tracking Echocardiography

Background and Objectives: Similar to diabetes, the presence of left ventricular (LV) diastolic function (DD) has been reported in various studies which were conducted with people with a diagnosis of an impaired fasting blood glucose (FBG). This study aimed to examine the effects of the fasting blood glucose (FBG) levels on the left atrial strain (LAS) estimated by two-dimensional echocardiography speckle tracking analyses in patients without known diabetes. Material and Methods: The study included 148 participants (74 female and 74 male) without a history of diabetes mellitus or chronic disease. The patients were divided into two groups as follows: individuals with an FBG < 100 mg/dL and those with an FBG between 100 and 125 mg/dL after at least 8 h of overnight fasting. According to these FBG levels, speckle tracking echocardiography (STE) measures were compared. Results: There was a significant decrease in the LA reservoir (52.3 ± 15 vs. 44.5 ± 10.7; p = 0.001) and conduit strain (36.9 ± 11.7 vs. 28.4 ± 9.7; p = 0.001) in the impaired FBG group. When the STE findings of both ventricles were compared, no significant difference was observed between the groups in right and left ventricular strain imaging. Conclusions: In the earliest stage of LVDD, changes in atrial functional parameters become particularly evident. Echocardiographic analyses of these parameters can help to diagnose and determine the degree of LVDD while the morphological parameters are still normal. The addition of LAS imaging to routine transthoracic echocardiography (TTE) studies in patients with an impaired FBG but without a DM diagnosis may be helpful in demonstrating subclinical LVDD or identifying patients at risk for LVDD in this patient group.

Left atrial phasic function: physiology, clinical assessment and prognostic value

Left atrial (LA) phasic function provides significant insights into the pathophysiology of cardiovascular disease. LA function is described in three phases: reservoir (atrial filling, during systole), conduit (passive emptying, during early diastole) and contractile (active emptying, during late diastole). LA phasic function can be evaluated by different imaging modalities, and a variety of techniques including volumetric analysis, deformation (strain) and Doppler methods. LA phasic function (particularly LA reservoir strain) is more sensitive and provides earlier detection of LA dysfunction than alterations in LA volume. LA function parameters have also demonstrated significant diagnostic and prognostic value, particularly in heart failure, atrial fibrillation and stroke. However, there remain barriers to implementation of phasic function parameters in clinical practice and guidelines. This review outlines the physiology of LA phasic function, methods of assessment, and its diagnostic and prognostic utility in varying pathologies.

The role and implications of left atrial fibrosis in surgical mitral valve repair as assessed by CMR: the ALIVE study design and rationale

Background

Patients with mitral regurgitation (MR) commonly suffer from left atrial (LA) remodeling. LA fibrosis is considered to be a key player in the LA remodeling process, as observed in atrial fibrillation (AF) patients. Literature on the presence and extent of LA fibrosis in MR patients however, is scarce and its clinical implications remain unknown. Therefore, the ALIVE trial was designed to investigate the presence of LA remodeling including LA fibrosis in MR patients prior to and after mitral valve repair (MVR) surgery.

Methods

The ALIVE trial is a single center, prospective pilot study investigating LA fibrosis in patients suffering from MR in the absence of AF (identifier NCT05345730). In total, 20 participants will undergo a CMR scan including 3D late gadolinium enhancement (LGE) imaging 2 week prior to MVR surgery and at 3 months follow-up. The primary objective of the ALIVE trial is to assess the extent and geometric distribution of LA fibrosis in MR patients and to determine effects of MVR surgery on reversed atrial remodelling.

Implications

This study will provide novel insights into the pathophysiological mechanism of fibrotic and volumetric atrial (reversed) remodeling in MR patients undergoing MVR surgery. Our results may contribute to improved clinical decision making and patient-specific treatment strategies in patients suffering from MR.

Peak left atrial longitudinal strain is associated with all-cause mortality in patients with ventricular functional mitral regurgitation

PURPOSE

Chronic mitral regurgitation promotes left atrial (LA) remodeling. However, the significance of LA dysfunction in the setting of ventricular functional mitral regurgitation (FMR) has not been fully investigated. Our aim was to assess the prognostic impact of peak atrial longitudinal strain (PALS), a surrogate of LA function, in patients with FMR and reduced left ventricular ejection fraction (LVEF).

METHODS

Patients with at least mild ventricular FMR and LVEF < 50% under optimized medical therapy who underwent transthoracic echocardiography at a single center were retrospectively identified in the laboratory database. PALS was assessed by 2D speckle tracking in the apical 4-chamber view and the study population was divided in two groups according to the best cut-off value of PALS, using receiver operating characteristics (ROC) curve analysis. The primary endpoint-point was all-cause mortality.

RESULTS

A total of 307 patients (median age 70 years, 77% male) were included. Median LVEF was 35% (IQR: 27 - 40%) and median effective regurgitant orifice area (EROA) was 15mm² (IQR: 9 - 22mm²). According to current European guidelines, 32 patients had severe FMR (10%). During a median follow-up of 3.5 years (IQR 1.4 - 6.6), 148 patients died. The unadjusted mortality incidence per 100 persons-years increased with progressively lower values of PALS. On multivariable analysis, PALS remained independently associated with all-cause mortality (adjusted hazard ratio 1.052 per % decrease; 95% CI: 1.010 - 1.095; P = 0.016), even after adjustment for several (n = 14) clinical and echocardiographic confounders.

CONCLUSION

PALS is independently associated with all-cause mortality in patients with reduced LVEF and ventricular FMR.

Speckle tracking echocardiography in early disease stages: a therapy modifier?

Echocardiography has been included as a first-line tool in several international guidelines for the management of patients with various cardiac diseases. Beyond diagnosis, echocardiographic examination helps in characterizing the severity of the condition since the very first stages. In particular, the application of second-level techniques, speckle tracking echocardiography in particular, can also reveal a subclinical dysfunction, while the standard parameters are in the normality range. The present review describes the potentialities of advanced echocardiography in different settings, including arterial hypertension, atrial fibrillation, diastolic dysfunction, and oncological patients, thus opening up potential starting points for its application as a clinical routine changer.

Feature-tracking computed tomography left atrial strain and long-term survival after transcatheter aortic valve implantation

AIMS

Aortic stenosis (AS) induces left atrial (LA) remodelling through the increase of left ventricular (LV) filling pressures. Peak LA longitudinal strain (PALS), reflecting LA reservoir function, has been proposed as a prognostic marker in patients with AS. Feature-tracking (FT) multi-detector computed tomography (MDCT) allows assessment of LA strain from MDCT data. The aim of this study is to investigate the association between PALS using FT MDCT and survival in patients with severe AS who underwent transcatheter aortic valve implantation (TAVI).

METHODS AND RESULTS

A total of 376 patients (mean age 80 ± 7 years, 53% male) who underwent MDCT before TAVI and had suitable data for assessment of PALS using dedicated FT software, were included. The patients were classified into four groups according to PALS quartiles; PALS > 19.3% (Q1, highest reservoir function), 15.0-19.3% (Q2), 9.1-14.9% (Q3), and ≤9.0% (Q4, lowest reservoir function). The primary outcome was all-cause mortality. During a median of 45 (22-68) months follow-up, 148 patients (39%) died. On multivariable Cox regression analysis, PALS was independently associated with all-cause mortality [hazard ratio (HR): 1.044, 95% confidence interval (CI): 1.012-1.076, P = 0.006]. Compared with patients in Q1, patients in Q3 and Q4 were associated with higher risk of mortality after TAVI [HR: 2.262 (95% CI: 1.335-3.832), P = 0.002 for Q3, HR: 3.116 (95% CI: 1.864-5.210), P < 0.001 for Q4].

CONCLUSION

PALS assessed with FT MDCT is independently associated with all-cause mortality after TAVI.

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.

Usefulness of the pulmonary venous flow waveform for assessing left atrial stiffness

PURPOSE

This study investigated the novel non-invasive left atrial (LA) stiffness parameter using pulmonary venous (PV) flow measurements and the clinical usefulness of the novel LA stiffness parameter.

METHODS

We retrospectively analyzed 237 patients who underwent right heart catheterization and echocardiography less than one week apart. From the pulmonary artery wedge pressure waveform, the difference between x-descent and v-wave (ΔP) was measured. Using the echocardiographic biplane method of disks, the difference between LA maximum volume and that just before atrial contraction (ΔV_MOD) was calculated, and the ΔP/ΔV_MOD was calculated as a standard LA stiffness index. From the PV flow waveform, the peak systolic velocity (S), peak diastolic velocity (D), and minimum velocity between them (R) were measured, and S/D, S/R, and D/R were calculated. From the speckle tracking echocardiography-derived time-LA volume curve, the difference between LA maximum volume and that just before atrial contraction (ΔV_STE) was measured. Each patient's prognosis was investigated until three years after echocardiography.

RESULTS

Among the PV flow parameters, D/R was significantly correlated with ΔP (r = 0.62), and the correlation coefficient exceeded that between S/D and ΔP (r =  - 0.39) or S/R and ΔP (r = 0.14). The [D/R]/ΔV_STE was significantly correlated with ΔP/ΔV_MOD (r = 0.61). During the follow-up, 37 (17%) composite endpoints occurred. Kaplan-Meier analysis showed that patients with [D/R]/ΔV_STE greater than 0.13 /mL were at higher risk of cardiac events.

CONCLUSION

The [D/R]/ΔV_STE was useful for assessing LA stiffness non-invasively and might be valuable in the prognostic evaluation of patients with cardiac diseases.

Left atrial strain and clinical outcome in patients with significant mitral regurgitation after surgical mitral valve repair

Background

This study aimed to investigate the prognostic value of left atrial (LA) strain in patients with significant mitral regurgitation (MR) after surgical mitral valve (MV) repair.

Methods

A total of 169 patients (age 55 ± 15 years, 88 men) with moderate or severe MR on echocardiogram at least 6 months after surgical MV repair for primary MR were studied. Two-dimensional, Doppler, and speckle tracking echocardiography including MR quantitative measures, chamber size, and LA strain were comprehensively analyzed. The primary outcome was a composite of cardiovascular death, heart failure hospitalization, and MV reoperation.

Results

During a median of 44.4 months [interquartile range (IQR): 18.7-70.3 months] of follow-up, 44 patients (26%) experienced clinical events; these patients had greater MR volume, elevated mean diastolic pressure gradient and pulmonary artery systolic pressure, and enlarged chamber size compared with patients who did not experience events. Patients with events showed significantly lower LA strain [13.3% (IQR: 9.3-23.8%) vs. 24.0% (IQR: 13.1-31.4%), p = 0.003] and higher MR volume/LA strain [3.09 ml/% (IQR: 2.06-5.80 ml/%) vs. 1.57 ml/% (IQR: 1.04-2.72 ml/%), p < 0.001] than those without events. MR volume/LA strain was a good predictor of clinical outcomes (cut-off 1.57 ml/%, area under the curve 0.754, p < 0.001). On multivariable Cox proportional analysis, MR volume/LA strain was independently associated with clinical outcomes (hazard ratio: 1.269, 95% confidence interval: 1.109-1.452, p < 0.001) along with pulmonary artery systolic pressure.

Conclusion

A measure of LA mechanical function relative to MR volume is associated with clinical outcomes in patients with significant MR after surgical MV repair.

Left atrial myocardial intrinsic function remodeling response to repair of primary mitral regurgitation

Severe mitral regurgitation (MR) is a common valve disease which is associated with high mortality, if only managed medically. MR produces chronic and progressive volume overload with left atrial (LA) and left ventricular (LV) dilatation and dysfunction, atrial fibrillation (AF) and eventually myocardial fibrosis, irrespective of ejection fraction (EF). Surgical correction (mitral valve repair) of MR removes the volume overload, hence unmasks pre-operative LV structure and function disturbances, including reduced EF and global longitudinal and circumferential strain, as well as LA volume and strain. This review aims at describing LA remodeling before and after surgical repair.

Association of longitudinal left atrial strain with mortality after tricuspid valve surgery

AIMS

Tricuspid valve (TV) surgery for functional tricuspid regurgitation (TR) is becoming more common, but the associated mortality remains high. Therefore, we evaluated the clinical and echocardiographic parameters associated with all-cause mortality in patients with severe functional TR who underwent TV surgery.

METHODS AND RESULTS

A total of 286 patients with severe functional TR who underwent TV replacement or repair was analysed between January 2006 and December 2017. We assessed changes in conventional echocardiographic parameters and strain, such as peak atrial longitudinal strain (PALS). During a median follow-up period of 5.3 years, 71 (24.8%) patients died due to any cause. When comparing groups with and without all-cause deaths, there were no significant differences in terms of sex, co-morbidities, medication use, and surgery type. However, patients who died were older and more likely to have refractory atrial fibrillation (AF). With multivariate Cox modelling, age >65 years (adjusted hazard ratio [HR], 2.81, 95% confidence interval [CI], 1.59-4.96; P < 0.001), refractory AF (adjusted HR, 2.84, 95% CI, 1.36-5.94; P = 0.006), lower albumin level (adjusted HR, 0.50, 95% CI, 0.31-0.82), and reduced PALS (adjusted HR, 1.87, 95% CI, 1.06-3.33; P = 0.032) were significant determinants of all-cause mortality. PALS decline was associated with refractory AF (adjusted HR, 5.74, 95% CI, 2.81-11.7; P < 0.001) and the absence of a Maze procedure (adjusted HR, 2.95, 95% CI, 1.51-5.78; P = 0.002).

CONCLUSIONS

A reduction in PALS was significantly associated with all-cause mortality in our cohort of patients with severe functional TR who underwent TV surgery. This phenomenon is related to refractory AF and more aggressive intervention for AF is necessary concomitant with TV surgery.

Left atrial strain determinants and clinical features according to the heart failure stages. New insight from EACVI MASCOT registry

Few studies analyzed left atrial (LA) peak atrial longitudinal strain (PALS) determinants, particularly across heart failure (HF) stages. We aimed to analyze the pathophysiological and clinical PALS correlates in a large multicentric prospective study. This is a multicenter prospective observational study enrolling 745 patients with HF stages. Data included PALS and left ventricular global longitudinal strain (LV-GLS). Exclusion criteria were: valvular prosthesis; atrial fibrillation; cardiac transplantation; poor acoustic window. Median global PALS was 17% [24–32]. 29% of patients were in HF-stage 0/A, 35% in stage-B, and 36% in stage-C. Together with age, the echocardiographic determinants of PALS were LA volume and LV-GLS (overall model R2 = 0.50, p < 0.0001). LV-GLS had the strongest association with PALS at multivariable analysis (beta: −3.60 ± 0.20, p < 0.0001). Among HF stages, LV-GLS remained the most important PALS predictor (p < 0.0001) whereas age was only associated with PALS in lower HF-stage 0/A or B (R = − 0.26 p < 0.0001, R = − 0.23 p = 0.0001). LA volume increased its association to PALS moving from stage 0/A (R = − 0.11; P = 0.1) to C (R = − 0.42; P < 0.0001). PALS was the single most potent echocardiographic parameter in predicting the HF stage (AUC for B vs. 0/A 0.81, and AUC vs. 0/A for C 0.76). PALS remained independently associated with HF stages after adjusting for ejection fraction, E/e′ ratio, and mitral regurgitation grade (p < 0.0001). Although influenced by LV-GLS and LA size across HF stages, PALS is incrementally and independently associated with clinical status. LA function may reflect a substantial part of the hemodynamic consequences of ventricular dysfunction.

The Impact of Left Atrial Mechanics on Adverse Events and Clinical Outcome After Cardiac Surgery

OBJECTIVES

Post-operative atrial fibrillation (POAF) represents a common complication after cardiac surgery that is associated with unfavorable clinical outcome. Identifying patients at risk for POAF is crucial but challenging. This study aimed to investigate the prognostic potential of speckle tracking echocardiography (STE) on POAF and fatal adverse events from a long-term perspective.

METHODS

A total of 124 patients undergoing elective cardiac surgery were prospectively enrolled and underwent pre-operative STE. Patients were followed prospectively for the occurrence of POAF within the entire hospitalization and reaching the secondary end-points cardiovascular (CV) and all-cause mortality.

RESULTS

Within the study population 43.5% (n = 53) of enrolled individuals developed POAF. After a median follow-up of 3.9 years, 25 (20.2%) patients died. We observed that patients presenting with POAF had lower global peak atrial longitudinal strain (PALS) values compared to the non-POAF arm (POAF: 14.8% [95% CI : 10.9-17.8] vs non-POAF: 19.4% [95% CI : 14.8-23.5], p < 0.001). Moreover, global PALS was a strong and independent predictor for POAF (adjusted Odds Ratio per 1-SD: 0.37 [95% CI : 0.22-0.65], p < 0.001), and independently associated with mortality (adjusted Hazard Ratio per 1-SD: 0.63 [95% CI : 0.40-0.99], p = 0.048). CART analysis revealed a cut-off value of < 17% global PALS as high-risk for both POAF and mortality.

CONCLUSION

Global PALS is associated with the development of POAF following surgery in an unselected patient population undergoing CABG and/or valve surgery. Since patients with global PALS <17% face a poor long-term prognosis, routine assessment of global PALS needs to be considered in terms of proper secondary prevention in the era of personalized medicine.

Incremental Prognosis by Left Atrial Functional Assessment: The Left Atrial Coupling Index in Patients With Floppy Mitral Valves

Background Emerging data suggest important prognostic value to left atrial (LA) characteristics, but the independent impact of LA function on outcome remains unsubstantiated. Thus, we aimed to define the incremental prognostic value of LA coupling index (LACI), coupling volumetric and mechanical LA characteristics and calculated as the ratio of left atrial volume index to tissue Doppler imaging a', in a large cohort of patients with isolated floppy mitral valve. Methods and Results All consecutive 4792 patients (61±16 years, 48% women) with isolated floppy mitral valve in sinus rhythm diagnosed at Mayo Clinic from 2003 to 2011, comprehensively characterized and with prospectively measured left atrial volume index and tissue Doppler imaging a' in routine practice, were enrolled, and their long-term survival analyzed. Overall, LACI was 5.8±3.7 and was <5 in 2422 versus ≥5 in 2370 patients. LACI was independently higher with older age, more mitral regurgitation (no 3.8±2.3, mild 5.1±3.0, moderate 6.5±3.8, and severe 7.8±4.3), and with diastolic (higher E/e') and systolic (higher end-systolic dimension) left ventricular dysfunction (all P≤0.0001). At diagnosis, higher LACI was associated with more severe presentation (more dyspnea, more severe functional tricuspid regurgitation, and elevated pulmonary artery pressure, all P≤0.0001) independently of age, sex, comorbidity index, ventricular function, and mitral regurgitation severity. During 7.0±3.0 years follow-up, 1146 patients underwent mitral valve surgery (94% repair, 6% replacement), and 880 died, 780 under medical management. In spline curve analysis, LACI ≥5 was identified as the threshold for excess mortality, with much reduced 10-year survival under medical management (60±2% versus 85±1% for LACI <5, P<0.0001), even after comprehensive adjustment (adjusted hazard ratio, 1.30 [95% CI, 1.10-1.53] for LACI ≥5; P=0.002). Association of LACI ≥5 with higher mortality persisted, stratifying by mitral regurgitation severity of LA enlargement grade (all P<0.001) and after propensity-score matching (P=0.02). Multiple statistical methods confirmed the significant incremental predictive power of LACI over left atrial volume index (all P<0.0001). Conclusions LA functional assessment by LACI in routine practice is achievable in a large number of patients with floppy mitral valve using conventional Doppler echocardiographic measurements. Higher LACI is associated with worse clinical presentation, but irrespective of baseline characteristics, LACI is strongly, independently, and incrementally determinant of outcome, demonstrating the crucial importance of LA functional response to mitral valve disease.

Prognostic Implications of Left Ventricular Global Longitudinal Strain in Patients With Surgically Treated Mitral Valve Disease and Preserved Ejection Fraction

Background

This study investigated whether left ventricular (LV) global longitudinal strain (LV-GLS), as an LV function parameter less affected by mitral valve (MV) repair or prosthesis, is associated with clinical outcomes in patients with surgically treated MV disease.

Methods

Among 750 patients who underwent MV surgery, we assessed LV-GLS by speckle tracking echocardiography in 344 patients (148 men, mean age 58 ± 13 years) who showed preserved LV ejection fraction on echocardiography between 6 months and 2 years after MV surgery and who did not undergo aortic valve surgery. The assessed clinical events included admission for worsening of heart failure and cardiac death.

Results

During a period of 42.4 ± 26.0 months, 32 (9.3%) patients were hospitalized for worsening heart failure, and 3 (0.8%) died due to cardiac causes. The absolute value of LV-GLS (|LV-GLS|) was significantly lower in patients with clinical events than in those without (12.1 ± 3.1 vs. 15.0 ± 3.2%, p < 0.001) despite comparable LV ejection fraction between groups. |LV-GLS| showed predictive value for clinical events (cut-off 13.9%, area under the curve 0.744, p < 0.001). Patients with |LV-GLS| ≤14.0% had poorer outcomes than those with |LV-GLS| >14.0% (log-rank p < 0.001). Prognosis was worse in patients with |LV-GLS| ≤14.0% and pulmonary hypertension than among those who with |LV-GLS| ≤14.0% without pulmonary hypertension (log rank p < 0.001). In nested Cox proportional hazard regression models, reduced |LV-GLS| was independently associated with the occurrence of clinical events.

Conclusions

In patients with surgically treated MV and preserved LV ejection fraction, assessment of LV-GLS provides functional information associated with cardiovascular outcomes.

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.

Cardiac Imaging for the Assessment of Left Atrial Mechanics Across Heart Failure Stages

The left atrium (LA) is emerging as a key element in the pathophysiology of several cardiac diseases due to having an active role in contrasting heart failure (HF) progression. Its morphological and functional remodeling occurs progressively according to pressure or volume overload generated by the underlying disease, and its ability of adaptation contributes to avoid pulmonary circulation congestion and to postpone HF symptoms. Moreover, early signs of LA dysfunction can anticipate and predict the clinical course of HF diseases before the symptom onset which, particularly, also applies to patients with increased risk of HF with still normal cardiac structure (stage A HF). The study of LA mechanics (chamber morphology and function) is moving from a research interest to a clinical application thanks to a great clinical, prognostic, and pathophysiological significance. This process is promoted by the technological progress of cardiac imaging which increases the availability of easy-to-use tools for clinicians and HF specialists. Two-dimensional (2D) speckle tracking echocardiography and feature tracking cardiac magnetic resonance are becoming essential for daily practice. In this context, a deep understanding of LA mechanics, its prognostic significance, and the available approaches are essential to improve clinical practice. The present review will focus on LA mechanics, discussing atrial physiology and pathophysiology of main cardiac diseases across the HF stages with specific attention to the prognostic significance. Imaging techniques for LA mechanics assessment will be discussed with an overlook on the dynamic (under stress) evaluation of the chamber.

Sacubitril/valsartan reduces indications for arrhythmic primary prevention in heart failure with reduced ejection fraction: insights from DISCOVER-ARNI, a multicenter Italian register

Aims

This sub-study deriving from a multicentre Italian register [Deformation Imaging by Strain in Chronic Heart Failure Over Sacubitril-Valsartan: A Multicenter Echocardiographic Registry (DISCOVER)-ARNI] investigated whether sacubitril/valsartan in addition to optimal medical therapy (OMT) could reduce the rate of implantable cardioverter-defibrillator (ICD) indications for primary prevention in heart failure with reduced ejection fraction (HFrEF) according to European guidelines indications, and its potential predictors.

Methods and results

In this observational study, consecutive patients with HFrEF eligible for sacubitril/valsartan from 13 Italian centres were included. Lack of follow-up or speckle tracking data represented exclusion criteria. Demographic, clinical, biochemical, and echocardiographic data were collected at baseline and after 6 months from sacubitril/valsartan initiation. Of 351 patients, 225 (64%) were ICD carriers and 126 (36%) were not ICD carriers (of whom 13 had no indication) at baseline. After 6 months of sacubitril/valsartan, among 113 non-ICD carriers despite having baseline left ventricular (LV) ejection fraction (EF) ≤ 35% and New York Heart Association (NYHA) class = II-III, 69 (60%) did not show ICD indications; 44 (40%) still fulfilled ICD criteria. Age, atrial fibrillation, mitral regurgitation > moderate, left atrial volume index (LAVi), and LV global longitudinal strain (GLS) significantly varied between the groups. With receiver operating characteristic curves, age ≥ 75 years, LAVi ≥ 42 mL/m2 and LV GLS ≥-8.3% were associated with ICD indications persistence (area under the curve = 0.65, 0.68, 0.68, respectively). With univariate and multivariate analysis, only LV GLS emerged as significant predictor of ICD indications at follow-up in different predictive models.

Conclusions

Sacubitril/valsartan may provide early improvement of NYHA class and LVEF, reducing the possible number of implanted ICD for primary prevention in HFrEF. Baseline reduced LV GLS was a strong marker of ICD indication despite OMT. Early therapy with sacubitril/valsartan may save infective/haemorrhagic risks and unnecessary costs deriving from ICDs.

Strain Echocardiography Is a Promising Tool for the Prognostic Assessment of Sarcoidosis

Sarcoidosis is a systemic chronic granulomatous disease with significant morbidity and mortality. Although basic transthoracic echocardiography (TTE) is not recommended for the assessment of sarcoidosis, speckle tracking echocardiography (STE) has emerged as more sensitive for the early detection of cardiac sarcoidosis and its outcome. The aim of the study was to assess the utility of left atrial and left ventricular longitudinal STE for the prediction of major adverse cardiac events (MACE) and sarcoidosis relapses. We enrolled 172 consecutive patients with sarcoidosis who underwent TTE and pulmonary function tests (PFTs). All patients were followed for a sarcoidosis relapse and MACE. During a median follow-up of 2217 days, 8 deaths, 23 MACE and 36 sarcoidosis relapses were observed. LV global longitudinal strain (GLS) was significantly lower in patients with MACE (p = 0.025). LV-GLS < 17.13% (absolute value) was identified as a fair predictor of MACE. Concerning the sarcoidosis control, TTE revealed a reduction of the LV ejection fraction (p = 0.0432), tricuspid annular plane systolic excursion (p = 0.0272) and global peak atrial longitudinal strain (PALS, p = 0.0012) in patients with relapses. PALS < 28.5% was the best predictor of a sarcoidosis relapse. Our results highlight a potential role of LV-GLS and PALS as prognostic markers in sarcoidosis, supporting the use of STE in the clinical management of these patients.

Non-Invasive Estimation of Left Ventricular Filling Pressure Based on Left Atrial Area Strain Measured With Transthoracic 3-Dimensional Speckle Tracking Echocardiography in Patients With Coronary Artery Disease

Background: Chronic elevation of left ventricular (LV) diastolic pressure (DP) or chronic elevation of left atrial (LA) pressure, which is required to maintain LV filling, may determine LA wall deformation. We investigated this issue using transthoracic 3-dimensional speckle tracking echocardiography (3D-STE).

Methods and Results: We retrospectively enrolled 75 consecutive patients with sinus rhythm and suspected stable coronary artery disease who underwent diagnostic cardiac catheterization and 3D-STE on the same day. We computed the global LA wall area change ratio, termed the global LA area strain (GLAS), during both the reservoir phase (GLAS-r) and contraction phase (GLAS-ct). The LVDP at end-diastole (LVEDP) and mean LVDP (mLVDP) were measured with a catheter-tipped micromanometer in each patient. GLAS-r and GLAS-ct were significantly correlated with both mLVDP (r=−0.70 [P<0.001] and r=0.71 [P<0.001], respectively) and LVEDP (r=−0.63 [P<0.001] and r=0.65 [P<0.001], respectively). In receiver operating characteristic curve analysis, the optimal cut-off values for diagnosing elevated LVEDP (≥16 mmHg) were 75.7% (sensitivity 83.3%, specificity 77.8%) for GLAS-r and −43.1% (sensitivity 90.0%, specificity 80.0%) for GLAS-ct. Similarly, for diagnosing elevated mLVDP (≥12 mmHg), the cut-off values were 63.6% (sensitivity 88.9%, specificity 80.3%) for GLAS-r and −26.2% (sensitivity 66.7%, specificity 97.0%) for GLAS-ct.

Conclusions: We showed that 3D-STE-derived GLAS values could be used to non-invasively diagnose elevated LV filling pressure.

Left atrial strain by speckle tracking predicts atrial fibrosis in patients undergoing heart transplantation

AIMS

In patients with heart failure (HF), chronically raised left ventricular (LV) filling pressures lead to progressive left atrial (LA) dysfunction and fibrosis. We aimed to assess the correlation of LA reservoir strain (peak atrial longitudinal strain, PALS) by speckle tracking echocardiography (STE) and LA fibrosis assessed by myocardial biopsy in patients undergoing heart transplantation (HTx).

METHODS AND RESULTS

Forty-eight patients with advanced HF [mean age 51.2 ± 8.1 years, 29% females; LV ejection fraction ≤25% and New York Heart Association (NYHA) class III-IV] referred for HTx were enrolled and underwent pre-operative echocardiographic evaluation, right heart catheterization, and cardiopulmonary exercise testing. Exclusion criteria were non-sinus rhythm, mechanical ventilation, severe mitral/tricuspid regurgitation, or other valvular disease and poor acoustic window. After HTx, LA bioptic samples were collected and analysed to determine the extent of myocardial fibrosis (%). LA fibrosis showed correlation with PALS (R = -0.88, P < 0.0001), VO2max (R = -0.68, P < 0.0001), NYHA class (R = 0.66, P < 0.0001), LA stiffness (R = 0.58, P = 0.0002), and E/e' (R = 0.44, P = 0.005), while poorly correlated with E/A ratio (R = 0.23, P = 0.21). PALS had a good correlation with NYHA class (R = -0.64, P < 0.0001), PAoP (R = -0.61, P = 0.03) and VO2max (R = 0.57, P = 0.0001). Multivariate regression analysis identified PALS (beta = -0.91, P < 0.001) and LA Volume (beta = -0.19, P = 0.03) as predictors of LA Fibrosis, while E/e' was not a significant predictor (beta = 0.15, P = 0.08).

CONCLUSION

Emerging as a possible index of myocardial fibrosis in patients with advanced HF, PALS could help to optimize the management and the selection of those patients with irreversible LA structural damage for advanced therapeutic strategies.

Novel Approaches in Cardiac Imaging for Non-invasive Assessment of Left Heart Myocardial Fibrosis

In the past, the identification of myocardial fibrosis was only possible through invasive histologic assessment. Although endomyocardial biopsy remains the gold standard, recent advances in cardiac imaging techniques have enabled non-invasive tissue characterization of the myocardium, which has also provided valuable insights into specific disease processes. The diagnostic accuracy, incremental yield and prognostic value of speckle tracking echocardiography, late gadolinium enhancement and parametric mapping modules by cardiac magnetic resonance and cardiac computed tomography have been validated against tissue samples and tested in broad patient populations, overall providing relevant clinical information to the cardiologist. This review describes the patterns of left ventricular and left atrial fibrosis, and their characterization by advanced echocardiography, cardiac magnetic resonance and cardiac computed tomography, allowing for clinical applications in sudden cardiac death and management of atrial fibrillation.

Speckle tracking echocardiography in primary mitral regurgitation: should we reconsider the time for intervention?

Thanks to the improvement in mitral regurgitation (MR) diagnostic and therapeutic management, with the introduction of minimally invasive techniques which have considerably reduced the individual surgical risk, the optimization of the timing for MR “open” or percutaneous surgical treatment has become a main concern which has highly raised scientific interest. In fact, the current indications for intervention in MR, especially in asymptomatic patients, rely on echocardiographic criteria with high severity cut-offs that are fulfilled only when not only mitral valve apparatus but also the cardiac chambers’ structure and function are severely impaired, which results in poor benefits for post-operative clinical outcome. This led to the need of new indices to redefine the optimal surgical timing in these patients. Speckle tracking echocardiography provides early markers of cardiac dysfunction due to subtle myocardial impairment; therefore, it could offer pivotal information in this setting. In fact, left ventricular and left atrial strains have already shown evidence about their usefulness in recognizing MR impact not only on symptoms and quality of life but also on cardiovascular events and new-onset atrial fibrillation in these patients. Moreover, right ventricular strain could be used to identify those patients with advanced cardiac damage and different grades of right ventricular dysfunction, which entails higher risks for cardiac surgery that could overweigh surgical benefits. This review aims to describe the importance of reconsidering the timing of intervention in MR and to analyze the potential additive value of speckle tracking echocardiography in this clinical setting.

Speckle Tracking Echocardiography: Early Predictor of Diagnosis and Prognosis in Coronary Artery Disease

Echocardiography represents a first level technique for the evaluation of coronary artery disease (CAD) which supports clinicians in the diagnostic and prognostic workup of these syndromes. However, visual estimation of wall motion abnormalities sometimes fails in detecting less clear or transient myocardial ischemia and in providing accurate differential diagnosis. Speckle tracking echocardiography (STE) is a widely available noninvasive tool that could easily and quickly provide additive information over basic echocardiography, since it is able to identify subtle myocardial damage and to localize ischemic territories in accordance to the coronary lesions, obtaining a clear visualization with a "polar map" useful for differential diagnosis and management. Therefore, it has increasingly been applied in acute and chronic coronary syndromes using rest and stress echocardiography, showing good results in terms of prediction of CAD, clinical outcome, left ventricular remodeling, presence, and quantification of new/residual ischemia. The aim of this review is to illustrate the current available evidence on STE usefulness for the assessment and follow-up of CAD, discussing the main findings on bidimensional and tridimensional strain parameters and their potential application in clinical practice.

Improved right ventricular function following transapical transcatheter mitral valve implantation for severe mitral regurgitation

Background

Transapical transcatheter mitral valve implantation (TMVI) may be a therapeutic option for patients with severe mitral regurgitation (MR) excluded from cardiac surgery due to excessive risk. Exclusion criteria frequently include pulmonary hypertension and right ventricular (RV) dysfunction. The effect of TMVI on RV function has not previously been well-characterized. The aim of this study was to examine the procedural and 3-month impact of TMVI on RV hemodynamics and function.

Methods

This was a multi-center, retrospective, observational cohort study of patients with >3+MR undergoing TMVI. Pre- and post-TMVI hemodynamics were assessed with right heart catheterization. RV function was assessed at baseline, pre-discharge and at 3-months by echocardiography.

Results

Forty-six patients (age 72±9 years; 34 men) with ≥3+MR underwent TMVI over a 5-year period. Successful device implantation was achieved in all patients with abolition of MR (p < 0.001) and reduction in left-ventricular end-diastolic volume (p = 0.001). RV stroke work index (RVSWI) increased intra-operatively (7 ± 4 g/m/beat/m² vs 11 ± 5 g/m/beat/m²; p < 0.001). At 3-months there were reductions in severity of tricuspid regurgitation (TR) (p < 0.001) and pulmonary artery systolic pressure (PASP) (49 ± 16 mmHg vs 36 ± 12 mmHg; p < 0.001), and improvements in RV fractional area change (28 ± 7% vs 34 ± 9%, p<0.001), tricuspid annular plane systolic excursion (TAPSE) (1.0 ± 0.3 vs 1.5 ± 0.5cm, p = 0.03), and RV free wall longitudinal strain (−14.2±5.0 vs −17.6±7.3, p = 0.05).

Conclusions

Transapical TMVI results in significant improvement of RV function that is sustained to 3-months as evidenced by improvements in RVSWI and RV fractional area change, as well as reductions in PASP and TR severity.