Novel Heart Failure Biomarkers Predict Improvement of Mitral Regurgitation in Patients Receiving Cardiac Resynchronization Therapy-The BIOCRT Study

Evolution and prognosis of tricuspid and mitral regurgitation following cardiac implantable electronic devices: a systematic review and meta-analysis

AIMS

Significant changes in tricuspid regurgitation (TR) and mitral regurgitation (MR) post-cardiac implantable electronic devices (CIEDs) are increasingly recognized. However, uncertainty remains as to whether the risk of CIED-associated TR and MR differs with right ventricular pacing (RVP) via CIED with trans-tricuspid RV leads, compared with cardiac resynchronization therapy (CRT), conduction system pacing (CSP), and leadless pacing (LP). The study aims to synthesize extant data on risk and prognosis of significant post-CIED TR and MR across pacing strategies.

METHODS AND RESULTS

We searched PubMed, EMBASE, and Cochrane Library databases published until 31 October 2023. Significant post-CIED TR and MR were defined as ≥ moderate. Fifty-seven TR studies (n = 13 723 patients) and 90 MR studies (n = 14 387 patients) were included. For all CIED, the risk of post-CIED TR increased [pooled odds ratio (OR) = 2.46 and 95% CI = 1.88-3.22], while the risk of post-CIED MR reduced (OR = 0.74, 95% CI = 0.58-0.94) after 12 and 6 months of median follow-up, respectively. Right ventricular pacing via CIED with trans-tricuspid RV leads was associated with increased risk of post-CIED TR (OR = 4.54, 95% CI = 3.14-6.57) and post-CIED MR (OR = 2.24, 95% CI = 1.18-4.26). Binarily, CSP did not alter TR risk (OR = 0.37, 95% CI = 0.13-1.02), but significantly reduced MR (OR = 0.15, 95% CI = 0.03-0.62). Cardiac resynchronization therapy did not significantly change TR risk (OR = 1.09, 95% CI = 0.55-2.17), but significantly reduced MR with prevalence pre-CRT of 43%, decreasing post-CRT to 22% (OR = 0.49, 95% CI = 0.40-0.61). There was no significant association of LP with post-CIED TR (OR = 1.15, 95% CI = 0.83-1.59) or MR (OR = 1.31, 95% CI = 0.72-2.39). Cardiac implantable electronic device-associated TR was independently predictive of all-cause mortality [pooled hazard ratio (HR) = 1.64, 95% CI = 1.40-1.90] after median of 53 months. Mitral regurgitation persisting post-CRT independently predicted all-cause mortality (HR = 2.00, 95% CI = 1.57-2.55) after 38 months.

CONCLUSION

Our findings suggest that, when possible, adoption of pacing strategies that avoid isolated trans-tricuspid RV leads may be beneficial in preventing incident or deteriorating atrioventricular valvular regurgitation and might reduce mortality.

Persistence of significant secondary mitral regurgitation post-cardiac resynchronization therapy and survival: a systematic review and meta-analysis : Mitral regurgitation and mortality post-CRT

Cardiac resynchronization therapy (CRT) significantly reduces secondary mitral regurgitation (MR) in patients with severe left ventricular systolic dysfunction. However, uncertainty remains as to whether improvement in secondary MR correlates with improvement with mortality seen in CRT. We conducted a meta-analysis to determine the association of persistent unimproved significant secondary MR (defined as moderate or moderate-to-severe or severe MR) compared to improved MR (no MR or mild MR) post-CRT with all-cause mortality, cardiovascular mortality, and heart failure hospitalization. A systematic search of PubMed, EMBASE, and Cochrane Library databases till July 31, 2022 identified studies reporting clinical outcomes by post-CRT secondary MR status. In 12 prospective studies of 4954 patients (weighted mean age 66.8 years, men 77.8%), the median duration of follow-up post-CRT at which patients were re-evaluated for significant secondary MR was 6 months and showed significant relative risk reduction of 30% compared to pre-CRT. The median duration of follow-up post-CRT for ascertainment of main clinical outcomes was 38 months. The random effects pooled hazard ratio (95% confidence interval) of all-cause mortality in patients with unimproved secondary MR compared to improved secondary MR was 2.00 (1.57-2.55); p < 0.001). There was insufficient data to evaluate secondary outcomes in a meta-analysis, but limited data that examined the relationship showed significant association of unimproved secondary MR with increased cardiovascular mortality and heart failure hospitalization. The findings of this meta-analysis suggest that lack of improvement in secondary MR post-CRT is associated with significantly elevated risk of all-cause mortality and possibly cardiovascular mortality and heart failure hospitalization. Future studies may investigate approaches to address persistent secondary MR post-CRT to help improved outcome in this population.

Predictors of persistence of functional mitral regurgitation after cardiac resynchronization therapy: Review of literature

Functional mitral regurgitation is a common finding among heart failure patients with ischemic and non-ischemic dilated cardiomyopathies. The presence of moderate or severe mitral regurgitation is associated with higher morbidity and mortality. Heart failure patients meeting electrocardiogram and left ventricle function criteria are good candidates for cardiac resynchronization therapy, which may reduce the degree of functional mitral regurgitation in the short and long term, specifically targeting myocardial dyssynchrony and inducing left ventricle reverse remodeling. In this article, we analyze data from the literature about predictors of mitral regurgitation improvement after cardiac resynchronization therapy implantation.

Predictive capacity of the brain natriuretic peptide in the screening of heart failure in a high altitude population

BACKGROUND

Heart failure (HF) is growing in importance as a significant cause of disease and mortality. When It is suspected, it can be ruled out if BNP values are below 100 pg/mL. Diagnostic certainty can be obtained if echocardiogram shows reduced ejection fraction, diastolic dysfunction or right-sided heart disease. Physiological changes at high altitude are known to affect BNP values. This study pretends to evaluate BNP values when used for HF diagnosis in Huancayo, Perú, a high altitude population located at 3,250 m above sea level.

METHODS

This is a cross-sectional, diagnostic test type study. A total of 83 medical charts of patients with suspected HF, admitted to the Emergency Room and Internal Medicine Service of Ramiro Prialé Prialé National Hospital, were reviewed. Data processing was performed with SPSS program for Windows version 21.0. Pearson's Chi Square test was used for categorical variables analysis and ANOVA for continuos variables. P values under 0.05 were considered significant.

RESULTS AND CONCLUSIONS

Medium age was 74 years. Patient's characteristics that were associated with confirmed HF and high BNP levels were the following: presence of fatigue, night cough, elevated heart rate, shortness of breath, history of lung fibrosis and decreased oxygen arterial saturation (p < 0.05) Pulmonary hypertension, mitral and tricuspid regurgitation, and cor pulmonale were also associated with higher BNP levels. Most subjects had BNP values >100 pg/mL, with low specificity for HF diagnosis (11.5 %). Individuals without heart failure had mean BNP values above 300 pg/mL; while individuals with cor pulmonale had a mean of 975 pg/mL. BNP values were high in patients with or without HF. A cut-off point of ≥130pg/mL is proposed to increase specificity. The predictive capacity of BNP for HF identification at this high altitude population is low because of a high number of false positive results.

Pathophysiology, Diagnosis, and New Therapeutic Approaches for Ischemic Mitral Regurgitation

Ischemic mitral regurgitation (MR) is a valvular complication frequently seen in patients with coronary artery disease and is associated with increased mortality and morbidity. Ischemic mitral regurgitation has a complex, heterogeneous, and still incompletely understood pathophysiology involving both the mitral valve and the left ventricle. The occurrence of valve regurgitation in patients with ischemic cardiomyopathy in return accelerates left ventricular remodelling and dysfunction, ultimately leading to irreversible heart failure. Diagnostic evaluation of ischemic MR is unique and different from the other causes of MR. The severity thresholds associated with outcomes are different from primary MR, and specific imaging characteristics are potentially useful to guide therapy. The use of imaging modalities such as 3-dimensional echocardiography and cardiac magnetic resonance imaging can refine the diagnostic evaluation and help in choosing the correct management. Although multiple treatments are available to improve ischemic MR, each therapeutic option is associated with limitations and incomplete success. Therapy has therefore to be individualised for each patient. Current options include optimal medical therapy, cardiac resynchronisation therapy, percutaneous or surgical revascularisation, surgical mitral repair or replacement, and new percutaneous interventions. This review aims to discuss the latest insights regarding the pathophysiology, diagnosis, and treatment of ischemic MR.

Biomarkers to predict the response to cardiac resynchronization therapy

Cardiac resynchronization therapy (CRT) is an established non-pharmacological treatment for selected heart failure patients with wide QRS duration. However, there is a persistent number of non-responders throughout. The prediction of the CRT response is paramount to adequately select the correct patients for CRT. One of the expanding fields of research is the development of biomarkers that predict the response to CRT. A review of the available literature on biomarkers in CRT patients has been performed to formulate a critical appraisal of the available data. The main conclusion of our review is that biomarker research in this patient population is very fragmented and broad. This results in the use of non-uniform endpoints to define the CRT response, which precludes an in-depth comparison of the available data. To improve research development in this field, a uniform definition of the CRT response and relevant endpoints is necessary to better predict the CRT response.

Functional Role of Natriuretic Peptides in Risk Assessment and Prognosis of Patients with Mitral Regurgitation

The management of mitral valve regurgitation (MR), a common valve disease, represents a challenge in clinical practice, since the indication for either surgical or percutaneous valve replacement or repair are guided by symptoms and by echocardiographic parameters which are not always feasible. In this complex scenario, the use of natriuretic peptide (NP) levels would serve as an additive diagnostic and prognostic tool. These biomarkers contribute to monitoring the progression of the valve disease, even before the development of hemodynamic consequences in a preclinical stage of myocardial damage. They may contribute to more accurate risk stratification by identifying patients who are more likely to experience death from cardiovascular causes, heart failure, and cardiac hospitalizations, thus requiring surgical management rather than a conservative approach. This article provides a comprehensive overview of the available evidence on the role of NPs in the management, risk evaluation, and prognostic assessment of patients with MR both before and after surgical or percutaneous valve repair. Despite largely positive evidence, a series of controversial findings exist on this relevant topic. Recent clinical trials failed to assess the role of NPs following the interventional procedure. Future larger studies are required to enable the introduction of NP levels into the guidelines for the management of MR.

Cardiac Resynchronization Therapy Optimization: A Comprehensive Approach

Since the first report on biventricular pacing in 1994, cardiac resynchronization therapy (CRT) has become standard for patients with advanced heart failure (HF) and ventricular conduction delay. CRT improves myocardial function by resynchronizing myocardial contraction, which results in reverse left ventricular remodeling and improves symptoms and clinical outcomes. Despite the accelerated development of CRT device technology and its increased application in treating HF patients, almost one-third of these patients do not respond to the therapy or gain any clinical benefit from device implantation. Over the last decade, multiple cardiac imaging modalities have provided a deeper understanding of myocardial pathophysiology, thereby improving HF treatment management. However, the optimal strategy for improving the CRT response remains debatable. This article provides an updated overview of the electropathophysiology of myocardial dysfunction in ventricular conduction delay and the diagnostic approaches involving the use of multiple modalities.

Galectin-3 and ST2 as predictors of therapeutic success in high-risk patients undergoing percutaneous mitral valve repair (MitraClip)

BACKGROUND

Percutaneous mitral valve repair (PMVR) is an interventional treatment option in patients with severe mitral regurgitation (MR) and at high risk for open-heart surgery. Currently, limited information exists about predictors of procedural success after PMVR. Galectin-3 (Gal-3) and suppression of tumorigenicity 2 (ST2) induce fibrotic alterations in severe MR and heart failure. We sought to examine the predictive value of Gal-3 and ST2 as specific indicators of therapeutic success in high-risk patients undergoing PMVR.

HYPOTHESIS

We hypothesize that extended cardiac fibrotic alterations might have impact on successful MR reduction after the MitraClip procedure.

METHODS

A total of 210 consecutive patients undergoing PMVR using the MitraClip system were included in this study. Procedural success was defined as an immediate reduction of MR by ≥2 grades, assessed by echocardiography. Venous blood samples were collected prior to PMVR and at 6 months follow-up for biomarker analysis.

RESULTS

After PMVR there was a significant reduction in the severity of MR (MR grade: 3 ±0.3 vs 1.6 ±0.6, P <0.001). Low baseline Gal-3 levels (PMVR_success : 22.0 ng/mL [IQR, 17.3-30.9] vs PMVR_failure : 30.6 ng/mL [IQR, 24.8-42.3], P <0.001) and ST2 levels (PMVR_success : 900.0 pg/mL [IQR, 619.5-1114.5] vs PMVR_failure : 1728.0 pg/mL [IQR, 1051.March 1, 1930], P < 0.001) were associated with successful MR reduction after PMVR. Also, ROC analysis identified low baseline Gal-3 and ST2 levels as predictors of therapeutic success after PMVR (AUC_Gal-3 :0.721 [IQR, 0.64-0.803], P < 0.001; AUC_ST2 : 0.807 [IQR, 0.741-0.872], P < 0.001).

CONCLUSIONS

There was an association between low Gal-3 and ST2 plasma levels and successful MR reduction in patients with severe MR undergoing PMVR using the MitraClip system.

Multi-Modality Imaging in the Evaluation and Treatment of Mitral Regurgitation

OPINION STATEMENT

Mitral regurgitation (MR) is frequent and associated with increased mortality and morbidity when severe. It may be caused by intrinsic valvular disease (primary MR) or ventricular deformation (secondary MR). Imaging has a critical role to document the severity, mechanism, and impact of MR on heart function as selected patients with MR may benefit from surgery whereas other will not. In patients planned for a surgical intervention, imaging is also important to select candidates for mitral valve (MV) repair over replacement and to predict surgical success. Although standard transthoracic echocardiography is the first-line modality to evaluate MR, newer imaging modalities like three-dimensional (3D) transesophageal echocardiography, stress echocardiography, cardiac magnetic resonance (CMR), and computed tomography (CT) are emerging and complementary tools for MR assessment. While some of these modalities can provide insight into MR severity, others will help to determine its mechanism. Understanding the advantages and limitations of each imaging modality is important to appreciate their respective role for MR assessment and help to resolve eventual discrepancies between different diagnostic methods. With the increasing use of transcatheter mitral procedures (repair or replacement) for high-surgical-risk patients, multimodality imaging has now become even more important to determine eligibility, preinterventional planning, and periprocedural guidance.

N-Terminal Pro B-Type Natriuretic Peptide and High-Sensitivity Cardiac Troponin T Levels Are Related to the Extent of Hibernating Myocardium in Patients With Ischemic Heart Failure

BACKGROUND

Increased N-terminal pro b-type natriuretic peptide (NT-proBNP) and high-sensitivity cardiac troponin T (hs-cTnT) can identify patients with heart failure (HF) who are at increased risk of cardiac events. The relationship of these biomarkers to the extent of hibernating myocardium and scar has not been previously characterized in patients with ischemic left ventricular dysfunction and HF.

METHODS

Patients with ischemic HF meeting recruitment criteria and undergoing perfusion and fluorodeoxyglucose-positron emission tomography to define myocardial hibernation and scar were included in the study. A total of 39 patients (mean age 67 ± 8 years) with New York Heart Association class II-IV HF and ischemic cardiomyopathy (ejection fraction [EF], 27.9% ± 8.5%) were enrolled in the study.

RESULTS

Serum NT-proBNP and hs-cTnT levels were elevated in patients with ≥ 10% hibernating myocardium compared with those with < 10% (NT-pro-BNP, 7419.10 ± 7169.5 pg/mL vs 2894.6 ± 2967.4 pg/mL; hs-cTnT, 789.3 ± 1835.3 pg/mL vs 44.8 ± 78.9 pg/mL; P < 0.05). The overall receiver operating characteristic under the curve value for NT-proBNP and hs-cTnT to predict hibernating myocardium was 0.76 and 0.78, respectively (P < 0.05). The NT-proBNP (P = 0.02) and hs-cTnT (P < 0.0001) levels also correlated with hibernation, particularly in patients with ≥ 10% scar, independent of EF, age, and estimated glomerular filtration rate. No differences were noted in biomarker levels for patients with vs those without ≥ 10% scar.

CONCLUSIONS

NT-proBNP and hs-cTnT levels are elevated in patients with ischemic HF hibernation and are correlated with the degree of hibernation but not with the presence or extent of scar. Taken together, these data support the novel concept that NT-proBNP and hs-cTnT release in patients with ischemic HF reflects the presence and extent of hibernating myocardium.