Left Atrial Volume Index and Outcome after Transcatheter Edge-to-edge Valve Repair for Secondary Mitral Regurgitation

Mismatch Between Residual Mitral Regurgitation and Left Atrial Pressure Predicts Prognosis After Transcatheter Edge-to-Edge Repair

BACKGROUND

The mechanism and impact of mismatch between residual mitral regurgitation (MR) and postprocedural left atrial pressure (LAP) after transcatheter edge-to-edge repair (TEER), which may adversely affect clinical outcome, is of great interest.

OBJECTIVES

This study aimed to examine the effect of hemodynamic mismatch after TEER on clinical outcomes in patients with heart failure due to severe MR and investigate the predictive factors for the mismatch using a prospective multicenter registry.

METHODS

We categorized 1,477 patients into optimal (residual MR grade ≤1 and postprocedural LAP ≤15 mm Hg), mismatched (residual MR grade >1 or postprocedural LAP >15 mm Hg), and poor (residual MR grade >1 and postprocedural LAP >15 mm Hg) groups and examined their prognosis. The primary endpoint was a composite of all-cause mortality and heart failure hospitalization.

RESULTS

There were 927 (62.7%), 459 (31.1%), and 91 (6.2%) patients categorized into optimal, mismatched, and poor groups, respectively. Cox regression analysis, referenced to the optimal group, revealed that the mismatched and poor groups exhibited a higher risk for the primary endpoint (HR: 1.55; 95% CI: 1.28-1.88; and HR: 1.95; 95% CI: 1.38-2.74, respectively). Six risk factors were identified as predictors of hemodynamic mismatch after TEER: body mass index, baseline left atrial volume index, atrial fibrillation, tricuspid annular plane systolic excursion value, preprocedural mean left atrial pressure, and postprocedural mean mitral valve pressure gradient.

CONCLUSIONS

Post-TEER hemodynamic mismatch between residual MR and postprocedural LAP was associated with a poor prognosis. Six readily accessible perioperative parameters predict the hemodynamic mismatch. (OCEAN-Mitral registry; UMIN000023653).

Management of secondary mitral regurgitation: from drugs to devices

Severe secondary mitral regurgitation carries a poor prognosis with one in five patients dying within 12 months of diagnosis. Fortunately, there are now a number of safe and effective therapies available to improve outcomes. Here, we summarise the most up-to-date treatments. Optimal guideline-directed medical therapy is the mainstay therapy and has been shown to reduce the severity of mitral regurgitation in 40-45% of patients. Rapid medication titration protocols reduce heart failure hospitalisation and facilitate earlier referral for device therapy. The pursuit of sinus rhythm in patients with atrial fibrillation has been shown to significantly reduce mitral regurgitation severity, as has the use of cardiac resynchronisation devices in patients who meet guideline-directed criteria. Finally, we highlight the key role of mitral valve intervention, particularly transcatheter edge-to-edge repair (TEER) for management of moderate-severe mitral regurgitation in carefully selected patients with poor left ventricular systolic function, with a number needed to treat of 3.1 to reduce heart failure hospitalisation and 5.9 to reduce all-cause death. To slow the rapid accumulation of morbidity and mortality, we advocate a proactive approach with accelerated medical optimisation, followed by management of atrial fibrillation and cardiac resynchronisation therapy if indicated, then, rapid referral to the Heart Team for consideration of mitral valve intervention in patients with ongoing symptoms and at least moderate-severe mitral regurgitation. Mitral TEER has been shown to be 'reasonably cost-effective' (but not cost-saving) in the UK in selected patients, although TEER remains underused with only 6.5 procedures per million population (pmp) compared with Germany (77 pmp), Switzerland (44 pmp) and the USA (32 pmp).

Regurgitant volume to LA volume ratio in patients with secondary MR: the COAPT trial

AIMS

The conceptual framework of proportionate vs. disproportionate mitral regurgitation (MR) translates poorly to individual patients with heart failure (HF) and secondary MR. A novel index, the ratio of MR severity to left atrial volume (LAV), may identify patients with 'disproportionate' MR and a higher risk of events. The objectives, therefore, were to investigate the prognostic impact of MR severity to LAV ratio on outcomes among HF patients with severe secondary MR randomized to transcatheter edge-to-edge repair (TEER) with the MitraClip™ device plus guideline-directed medical therapy (GDMT) vs. GDMT alone in the COAPT trial.

METHODS AND RESULTS

The ratio of pre-procedural regurgitant volume (RVol) to LAV was calculated from baseline transthoracic echocardiograms. The primary endpoint was 2-year covariate-adjusted rate of HF hospitalization (HFH). Among 567 patients, the median RVol/LAV was 0.67 (interquartile range 0.48-0.91). In patients randomized to GDMT alone, lower RVol/LAV was independently associated with an increased 2-year risk of HFH (adjHR: 1.77; 95% CI: 1.20-2.63). RVol/LAV was a stronger predictor of adverse outcomes than RVol or LAV alone. Treatment with TEER plus GDMT compared with GDMT alone was associated with lower 2-year rates of HFH both in patients with low and high RVol/LAV (Pinteraction = 0.28). Baseline RVol/LAV ratio was unrelated to 2-year mortality, health status, or functional capacity in either treatment group.

CONCLUSION

Low RVol/LAV ratio was an independent predictor of 2-year HFH in HF patients with severe MR treated with GDMT alone in the COAPT trial. TEER improved outcomes regardless of baseline RVol/LAV ratio.

CLINICAL TRIAL REGISTRATION

Trial Name: Cardiovascular Outcomes Assessment of the MitraClip Percutaneous Therapy for Heart Failure Patients With Functional Mitral Regurgitation (The COAPT Trial) (COAPT) ClinicalTrial.gov Identifier NCT01626079URL https://clinicaltrials.gov/ct2/show/NCT01626079.

Mitral regurgitation in heart failure with preserved ejection fraction: The interplay of valve, ventricle, and atrium

Mitral regurgitation (MR) is highly prevalent among patients with heart failure and preserved ejection fraction (HFpEF). Despite this combination being closely associated with unfavourable outcomes, it remains relatively understudied. This is partly due to the inherent heterogeneity of patients with HFpEF. To address this gap, dissecting HFpEF into mechanism-based phenotypes may offer a promising avenue for advancing our comprehension of these complex intertwined conditions. This review employs the validated CircAdapt model to explore the haemodynamic implications of moderate to severe MR across a well-defined spectrum of myocardial disease, characterized by impaired relaxation and reduced myocardial compliance. Both heart failure and mitral valve disease share overlapping symptomatology, primarily attributed to elevated pulmonary pressures. The intricate mechanisms contributing to these elevated pressures are multifaceted, potentially influenced by diastolic dysfunction, left atrial myopathy, and MR. Accurate evaluation of the haemodynamic and clinical impact of MR necessitates a comprehensive approach, taking into account the characteristics of both the left atrium and left ventricle, as well as their intricate interactions, which may currently be underemphasized in diagnostic practice. This holistic assessment is imperative for enhancing our understanding and refining therapeutic strategies within this patient cohort.

Chronic mild to moderate mitral regurgitation will not have an impact on left atrial strain parameters in the pediatric population

BACKGROUND

Left atrial strain (LAS) analysis represents a newer non-invasive, sensitive and specific technique for assessing left atrial (LA) function and early detection of its deformation and dysfunction. However, its applicability in mitral regurgitation (MR) in pediatric population remains unexplored, raising pertinent questions regarding its potential role in evaluating the severity and progression of the disease.

OBJECTIVE

To investigate the impact of chronic MR in children and adolescents on LA remodeling and function.

METHODS

The study included 100 participants. Patients with primary and secondary chronic MR lasting at least 5 years fit our inclusion criteria. The exclusion criteria from the study were: patients with functional mitral regurgitation due to primary cardiomyopathies, patients with artificial mitral valve, patients with MR who had previously undergone surgery due to obstructive lesions of the left heart (aortic stenosis, coarctation of the aorta), patients with significant atrial rhythm disorders (atrial fibrillation, atrial flutter). The echocardiographic recordings were conducted by two different cardiologists. Outcome data was reported as mean and standard deviation (SD) or median and interquartile range (Q1-Q3).

RESULTS

The study included 100 participants, of whom 50 had MR and the remaining 50 were without MR. The average age of all participants was 15.8 ± 1.2 years, with a gender distribution of 37 males and 63 females. There was a significant difference in the values of LA volume index (LAVI), which were higher in patients with MR (p= 0.0001), S/D ratio (and parameters S and D; p= 0.001, p= 0.0001, p= 0.013), mitral annulus radius (p= 0.0001), E/A ratio (p= 0.0001), as well as septal e' (m/s), lateral e' (m/s), and average E/e' ratio, along with the values of TV peak gradient and LV global longitudinal strain (%). There was no significant difference in LA strain parameters, nor in LA stiffness index (LASI).

CONCLUSION

Our findings revealed significant differences in several echocardiographic parameters in pediatric patients with MR relative to those without MR, providing insight into the multifaceted cardiac structural and functional effects of MR in this vulnerable population.

Updates in heart failure: sodium glucose co-transporter 2 inhibitors and beyond – major changes are coming

Prevalence of heart failure is increasing worldwide mainly due to the ageing of the population and the improvement in diagnosis and treatment. In recent years, huge progress has been made in the management of heart failure patients. A new definition of chronic heart failure based on left ventricular ejection fraction and its possible trajectories has been reported. New drug classes have been introduced for the treatment of chronic heart failure. In particular, the prognostic benefit of sodium glucose co-transporter 2 inhibitors was demonstrated across all the heart failure phenotypes. Therapies for patients with advanced heart failure (long-term mechanical circulatory supports and heart transplantation) are now indicated also in the case of mild-to-moderate symptoms but with high risk of progression. In patients with acute heart failure, monitoring of urinary sodium and the use of acetazolamide may lead to better decongestion. Importantly, pre- and postdischarge assessment should lead to optimal treatment. Devices and telemonitoring can also be of help. Cardiovascular and noncardiovascular comorbidities are major determinants of the clinical course and need proper management. This review will summarize these important advances.

Heart failure: an update from the last years and a look at the near future

In the last years, major progress occurred in heart failure (HF) management. Quadruple therapy is now mandatory for all the patients with HF with reduced ejection fraction. Whilst verciguat is becoming available across several countries, omecamtiv mecarbil is waiting to be released for clinical use. Concurrent use of potassium-lowering agents may counteract hyperkalaemia and facilitate renin-angiotensin-aldosterone system inhibitor implementations. The results of the EMPagliflozin outcomE tRial in Patients With chrOnic heaRt Failure With Preserved Ejection Fraction (EMPEROR-Preserved) trial were confirmed by the Dapagliflozin in Heart Failure with Mildly Reduced or Preserved Ejection Fraction (DELIVER) trial, and we now have, for the first time, evidence for treatment of also patients with HF with preserved ejection fraction. In a pre-specified meta-analysis of major randomized controlled trials, sodium-glucose co-transporter-2 inhibitors reduced all-cause mortality, cardiovascular (CV) mortality, and HF hospitalization in the patients with HF regardless of left ventricular ejection fraction. Other steps forward have occurred in the treatment of decompensated HF. Acetazolamide in Acute Decompensated Heart Failure with Volume Overload (ADVOR) trial showed that the addition of intravenous acetazolamide to loop diuretics leads to greater decongestion vs. placebo. The addition of hydrochlorothiazide to loop diuretics was evaluated in the CLOROTIC trial. Torasemide did not change outcomes, compared with furosemide, in TRANSFORM-HF. Ferric derisomaltose had an effect on the primary outcome of CV mortality or HF rehospitalizations in IRONMAN (rate ratio 0.82; 95% confidence interval 0.66-1.02; P = 0.070). Further options for the treatment of HF, including device therapies, cardiac contractility modulation, and percutaneous treatment of valvulopathies, are summarized in this article.

Acute effect of edge-to-edge repair of mitral regurgitation on left heart mechanics and health status

AIMS

Examine the impact of acute changes in left heart strain and volumes with percutaneous edge-to-edge MitraClip repair on improvement in health status assessed using Kansas City Cardiomyopathy Questionnaire-12 (KCCQ-12) score.

METHODS

Changes in left atrial strain, left ventricular (LV) global longitudinal strain (LVGLS), LV end-systolic volume (LVESV), and end-diastolic volume (LVEDV) were evaluated in 50 patients undergoing MitraClip repair for symptomatic primary mitral regurgitation (PMR) and secondary mitral regurgitation (SMR) on transthoracic echocardiography before and 1 month after MitraClip. Multivariable regression was used to evaluate changes in left heart strain and volumes as predictors of change in KCCQ-12 scores, adjusting for baseline clinical and echocardiographic characteristics.

RESULTS

Both PMR and SMR patients had significant increase in LVGLS and reduction in LVEDV and LVESV (P < 0.05) after MitraClip, reduction trend in left atrial conduit strain (PMR P = 0.053; SMR P = 0.12) but no significant change in LV ejection fraction. KCCQ-12 score improved significantly in both PMR (P < 0.001) and SMR cohorts (P < 0.001). Higher delta KCCQ-12 tertiles were associated with greater reduction in LVEDV (P = 0.022) after MitraClip. On multiple regression analysis, lower preprocedural Society of Thoracic Surgeons for Mitral Valve Replacement and KCCQ-12 score, and greater reduction in LVESV and left atrial strain conduit phase were associated with KCCQ-12 score improvement (P < 0.001).

CONCLUSION

There is a significant increase in LVGLS and reduction in LVEDV, LVESV and left atrial strain conduit after edge-to-edge MitraClip repair in both PMR and SMR. Lower preprocedural Society of Thoracic Surgeons for Mitral Valve Replacement and KCCQ-12 score, and greater reduction in LVESV and left atrial conduit strain were associated with KCCQ-12 score improvement after MitraClip. Further studies are warranted to understand the mechanism and significance of our findings.