Drug and Device Effects on Peak Oxygen Consumption, 6-Minute Walk Distance, and Natriuretic Peptides as Predictors of Therapeutic Effects on Mortality in Patients With Heart Failure and Reduced Ejection Fraction

Practical Aspects of Using Large Language Models to Screen Abstracts for Cardiovascular Drug Development: Cross-Sectional Study

Unlabelled

Cardiovascular drug development requires synthesizing relevant literature about indications, mechanisms, biomarkers, and outcomes. This short study investigates the performance, cost, and prompt engineering trade-offs of 3 large language models accelerating the literature screening process for cardiovascular drug development applications.

Effects of dapagliflozin and empagliflozin on 6-min walk distance in heart failure with preserved and reduced ejection fraction: A systematic review and meta-analysis of randomized controlled trials involving 2624 patients

BACKGROUND

Dapagliflozin and empagliflozin are antidiabetic medications. They are the first two sodium-glucose cotransporter-2 inhibitors (SGLT2i) to receive the US Food and Drug Administration approval to manage heart failure. Emerging new trials have examined changes in the 6-min walk distance as a clinically significant response to dapagliflozin and empagliflozin in patients with heart failure with reduced ejection fraction (HFpEF) and heart failure with preserved ejection fraction (HFrEF). This meta-analysis aims to evaluate the effects of dapagliflozin and empagliflozin on the 6-min walk distance in patients with HFpEF and HFrEF. To our knowledge, no such meta-analysis has been published.

METHODS

Following the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines, we searched four electronic databases (PubMed, EMBASE, Cochrane Library, and Web of Science) to identify eligible studies reported up to December 16, 2023. Using Review Manager software, we reported outcomes as risk ratios (RRs) or mean difference (MD) and confidence intervals (CIs). A p-value ≤ 0.05 is considered as statistically significant.

RESULTS

The meta-analysis included a total of 8 studies with 2624 patients. Overall, the results showed insignificant differences in the 6-min walk between the SGLT2i and placebo (MD 24, 95% CI -0.30 to 18.78, p = 0.06). Results became significant after resolving the heterogeneity (MD 6.72, 95% CI 0.13 to 13.31, p = 0.05). Notably, the results of each drug separately were insignificant. More robust observations occurred in the HFpEF group (MD 10.73, 95% CI 1.08 to 20.39, p = 0.03). Compared to placebo, patients on dapagliflozin reported significant improvement in the Kansas City Cardiomyopathy Questionnaire Clinical Summary (KCCQ-CS) and Overall Summary (KCCQ-OS) with values of MD 5.18 (95% CI 2.80 to 7.57, p < 0.0001) and MD 4.06 (95% CI 1.66 to 6.46, p = 0.0009), respectively. The dapagliflozin group and patients with HFpEF had reported a significant reduction in their weight compared with the control group (MD -0.59 CI -1.09 to -0.08, p = 0.02) and (MD -0.80 CI -1.47 to -0.13, p = 0.02), respectively. No significant side effects were observed for dapagliflozin or empagliflozin.

CONCLUSION

Patients with HFpEF experienced benefits from SGLT2i administration, as evidenced by improved 6-min walk distances and weight reduction. Dapagliflozin demonstrated clinical and overall improvements in KCCQ scores and was more effective in reducing weight than the placebo. Both Dapagliflozin and Empagliflozin were well-tolerated and exhibited favorable safety profiles. Future studies could benefit from a larger patient population, a longer follow-up period, and a broader range of SGLT2i.

Prediction of recurrent heart failure hospitalizations and mortality using the echocardiographic Killip score

AIM

Examine the performance of a simple echocardiographic "Killip score" (eKillip) in predicting heart failure (HF) hospitalizations and mortality after index event of decompensated HF hospitalization.

METHODS

HF patients hospitalized at our facility between 03/2019-03/2021 who underwent an echocardiography during their index admission were included in this retrospective analysis. The cohort was divided into 4 classes of eKillip according to: stroke volume index (SVI) < 35ml/m2 > and E/E' ratio < 15 > . An eKillip Class I was defined as SVI ≥ 35ml/m2 and E/E' ≤ 15 and was used as reference.

RESULTS

Included 751 patients, median age 78.1 (IQR 69.3-86) years, 59% men, left ventricular ejection fraction 45 (IQR 30-60)%, brain natriuretic peptide levels 634 (IQR 331-1222)pg/ml. Compared with eKillip Class I, a graded increase in the combined endpoint of 30-day mortality and rehospitalizations rates was noted: (Class II: HR 1.77, CI 0.95-3.33, p = 0.07; Class III: HR 1.94, CI 1.05-3.6, p = 0.034; Class IV: HR 2.9, CI 1.64-5.13, p < 0.001 respectively), which overall persisted after correction for clinical (Class II: HR 1.682, CI 0.9-3.15, p = 0.105; Class III: HR 2.104, CI 1.13-3.9, p = 0.019; Class IV: HR 2.74, CI 1.54-4.85, p = 0.001 respectively) or echocardiographic parameters (Class II: HR 1.92, CI 1.02-3.63, p = 0.045; Class III: HR 1.54, CI 0.81-2.95, p = 0.189; Class IV: HR 2.04, CI 1.1-3.76, p = 0.023 respectively). Specifically, the eKillip Class IV group comprised one-third of the patient population and persistently showed increased risk of 30-day HF hospitalizations or mortality following multivariate analysis.

CONCLUSION

A simple echocardiographic score can assist identifying high-risk decompensated HF patients for recurrent hospitalizations and mortality.

The Pathophysiology(ies) of Heart Failure in Adults with Congenital Heart Disease

There is a growing, aging population of adults with congenital heart disease (CHD) with an increasing incidence of heart failure. Unquestioning extrapolation of widely applicable definitions of heart failure and guidelines for managing heart failure in adults with acquired heart failure to adults with CHD can be problematic. A nuanced and flexible application of clinical judgment founded on a deep understanding of underlying pathophysiology is needed to most effectively apply the many recent advances in managing acquired heart failure to the care of adults with CHD.

Sacubitril/Valsartan in Heart Failure with Hypertension Patients: Real-World Experiences on Different Ages, Drug Doses, and Renal Functions

INTRODUCTION

Hypertension is a significant risk factor in heart failure for worldwide patients. More than half of hypertensive patients suffer from heart failure. Recently, sacubitril/valsartan (sac/val) has been approved as an antihypertensive agent in China and Japan. Additionally, it is not approved for treating hypertension in Europe or the USA.

AIM

To accumulate more real-world experiences to investigate the effectiveness and optimize clinical medication of sac/val in hypertensive patients with heart failure.

METHODS

We retrospectively enrolled adult patients diagnosed with hypertension (HTN) and heart failure (HF) and newly treated with sac/val. The baseline characteristics and clinical outcomes were retrospectively extracted from electronic medical records (EMR) in three centers. The efficacy and safety of sac/val were first analyzed in all enrolled patients. Stratified analyses were conducted in patients with different ages (≥ 65, < 65), maximum tolerated doses (≥ 200 mg/days, < 200 mg/days), and renal functions (e-GFR ≥ 60 ml/min/1.73 m2, < 60 ml/min/1.73 m2).

RESULTS

Overall, 794 patients diagnosed with both HF and HTN were included in our study. During follow-up, significant reductions were found in blood pressure (BP) (SBP 12.8 ± 21.2 mmHg, P < 0.001, DBP 7.1 ± 16.5 mmHg, P < 0.001), and cardiac biomarkers (cardiac troponin 1.78 ± 19.1 ng/mL, P < 0.001, NT-proBNP 1403 ± 6937 pg/mL, P < 0.001) from baseline. In stratification analyses, the lower dosage group earned a higher BP control rate (83.4% vs. 75.6%, P = 0.025) and an overall improvement rate of cardiac indicators (61.3% vs. 48.0%, P = 0.002). The younger patients' group had significantly less cumulative hazard of recurrent cerebral-cardiovascular events than the elder group (log-rank P value < 0.001). Patients with renal dysfunction were observed with more AE incidences.

CONCLUSIONS

Sac/val could reduce BP and improve cardiac structural and functional parameters in hypertensive patients with HF, even with less than target doses. However, more attention should be paid to older patients and renal dysfunction patients when using sac/val because of additional risks in adverse events.

NT-proBNP and ICD in Nonischemic Systolic Heart Failure: Extended Follow-Up of the DANISH Trial

OBJECTIVES

In this extended follow-up study of the DANISH (Danish Study to Assess the Efficacy of Implantable Cardioverter Defibrillators in Patients with Non-ischemic Systolic Heart Failure on Mortality) trial, adding 4 years of additional follow-up, we examined the effect of implantable cardioverter-defibrillator (ICD) implantation according to baseline N-terminal pro-B-type natriuretic peptide (NT-proBNP) level.

BACKGROUND

In the DANISH trial, NT-proBNP level at baseline appeared to modify the response to ICD implantation.

METHODS

In the DANISH trial, 1,116 patients with nonischemic systolic HF were randomized to receive an ICD (N = 556) or usual clinical care (N = 550). Outcomes were analyzed according to NT-proBNP levels (below/above median) at baseline. The primary outcome was death from any cause.

RESULTS

All 1,116 patients in the DANISH trial had an available NT-proBNP measurement at baseline (median: 1,177 pg/mL; range: 200-22,918 pg/mL). There was a trend toward a reduction in all-cause death with ICD implantation, compared with usual clinical care, in patients with NT-proBNP levels lower than the median (HR: 0.75 [95% CI: 0.55-1.03]), but not in those with higher NT-proBNP levels (HR: 0.95 [95% CI: 0.74-1.21]) (P_interaction = 0.28). Similarly, ICD implantation significantly reduced the rate of cardiovascular (CV) and sudden cardiovascular death (SCD) in patients with NT-proBNP levels lower than the median (CV death, HR: 0.69 [95% CI: 0.47-1.00]; SCD, HR: 0.37 [95% CI: 0.19-0.75]), but not in those with higher levels (CV death, HR: 0.94 [95% CI: 0.70-1.25]; SCD, HR: 0.86 [95% CI: 0.49-1.51]) (P_interaction = 0.20 and 0.08 for CV death and SCD, respectively).

CONCLUSIONS

Lower baseline NT-proBNP levels could identify patients with nonischemic systolic HF who may derive benefit from ICD implantation. (Danish Study to Assess the Efficacy of Implantable Cardioverter Defibrillators in Patients with Non-ischemic Systolic Heart Failure on Mortality [DANISH]; NCT00542945).

Efficacy and Safety of Dapagliflozin in Heart Failure With Reduced Ejection Fraction According to N-Terminal Pro-B-Type Natriuretic Peptide: Insights From the DAPA-HF Trial

BACKGROUND

Effective therapies for HFrEF usually reduce NT-proBNP (N-terminal pro-B-type natriuretic peptide) levels, and it is important to establish whether new treatments are effective across the range of NT-proBNP.

METHODS

We evaluated both these questions in the DAPA-HF (Dapagliflozin and Prevention of Adverse Outcomes in Heart Failure) trial. Patients in New York Heart Association functional class II to IV with a left ventricular ejection fraction ≤40% and a NT-proBNP level ≥600 pg/mL (≥600 ng/L; ≥400 pg/mL if hospitalized for HF within the previous 12 months or ≥900 pg/mL if atrial fibrillation/flutter) were eligible. The primary outcome was the composite of an episode of worsening HF or cardiovascular death.

RESULTS

Of the 4744 randomized patients, 4742 had an available baseline NT-proBNP measurement (median, 1437 pg/mL [interquartile range, 857-2650 pg/mL]). Compared with placebo, treatment with dapagliflozin significantly reduced NT-proBNP from baseline to 8 months (absolute least-squares mean reduction, -303 pg/mL [95% CI, -457 to -150 pg/mL]; geometric mean ratio, 0.92 [95% CI, 0.88-0.96]). Dapagliflozin reduced the risk of worsening HF or cardiovascular death, irrespective of baseline NT-proBNP quartile; the hazard ratio for dapagliflozin versus placebo, from lowest to highest quartile was 0.43 (95% CI, 0.27-0.67), 0.77 (0.56-1.04), 0.78 (0.60-1.01), and 0.78 (0.64-0.95); P for interaction=0.09. Consistent benefits were observed for all-cause mortality. Compared with placebo, dapagliflozin increased the proportion of patients with a meaningful improvement (≥5 points) in Kansas City Cardiomyopathy Questionnaire total symptom score (P for interaction=0.99) and decreased the proportion with a deterioration ≥5 points (P for interaction=0.87) across baseline NT-proBNP quartiles.

CONCLUSIONS

In patients with HFrEF, dapagliflozin reduced NT-proBNP by 300 pg/mL after 8 months of treatment compared with placebo. In addition, dapagliflozin reduced the risk of worsening HF and death, and improved symptoms, across the spectrum of baseline NT-proBNP levels included in DAPA-HF. Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT03036124.

Combination pharmacotherapies for cardiac reverse remodeling in heart failure patients with reduced ejection fraction: A systematic review and network meta-analysis of randomized clinical trials

Pharmacotherapies, including angiotensin-converting enzyme inhibitors (ACEIs), angiotensin receptor II blockers (ARBs), β-blockers (BBs), mineralocorticoid receptor antagonists (MRAs) and angiotensin receptor blocker-neprilysin inhibitor (ARNI), have played a pivotal role in reducing in-hospital and mortality in heart failure patients with reduced ejection fraction (HFrEF). However, effects of the five drug categories used alone or in combination for cardiac reverse remodeling (CRR) in these patients have not been systematically evaluated. A Bayesian network meta-analysis was conducted based on 55 randomized controlled trials published between 1989 and 2019 involving 12,727 patients from PubMed, EMBASE, Cochrane Library, and Clinicaltrials.gov. The study is registered with PROSPERO (CRD42020170457). Our primary outcomes were CRR indicators, including changes of left ventricular ejection fraction (LVEF), left ventricular end-diastolic volume (LVEDV) and end-systolic volume (LVESV), indexed LVEDV (LVEDVI) and LVESV (LVESVI), and left ventricular end-diastolic dimension (LVEDD) and end-systolic dimension (LVESD); Secondary outcomes were functional capacity comprising New York Heart Association (NYHA) class and 6-min walking distance (6MWD); cardiac biomarkers involving B type natriuretic peptide (BNP) and N-terminal pro-BNP (NT-proBNP). The effect sizes were presented as the mean difference with 95% credible intervals. According to the results, all dual-combination therapies except ACEI+ARB were significantly more associated with LVEF or NYHA improvement than placebo, ARB+BB and ARNI+BB were the top two effective dual-combinations in LVEF improvement (+7.59% [+4.27, +11.25] and +7.31% [+3.93, +10.97] respectively); ACEI+BB was shown to be superior to ACEI in reducing LVEDVI and LVESVI (-6.88 mL/m² [-13.18, -1.89] and -10.64 mL/m² [-18.73, -3.54] respectively); ARNI+BB showed superiority over ACEI+BB in decreasing the level of NT-proBNP (-240.11 pg/mL [-456.57, -6.73]). All tri-combinations were significantly more effective than placebo in LVEF improvement, and ARNI+BB+MRA ranked first (+21.13% [+14.34, +28.13]); ACEI+BB+MRA was significantly more associated with a decrease in LVEDD than ACEI (-6.57 mm [-13.10, -0.84]). A sensitivity analysis ignoring concomitant therapies for LVEF illustrated that all the five drug types except ARB were shown to be superior to placebo, and ARNI ranked first (+4.83% [+1.75, +7.99]). In conclusion, combination therapies exert more benefits on CRR for patients with HFrEF. Among them, ARNI+BB, ARB+BB, ARNI+BB+MRA and ARB+BB+MRA were the top two effective dual and triple combinations in LVEF improvement, respectively; The new "Golden Triangle" of ARNI+BB+MRA was shown to be superior to ACEI+BB+MRA or ARB+BB+MRA in LVEF improvement.

Clinical Studies of Cell Therapy in Cardiovascular Medicine: Recent Developments and Future Directions

Given the rising prevalence of cardiovascular disease worldwide and the limited therapeutic options for severe heart failure, novel technologies that harness the regenerative capacity of the heart are sorely needed. The therapeutic use of stem cells has the potential to reverse myocardial injury and improve cardiac function, in contrast to most current medical therapies that only mitigate heart failure symptoms. Nearly 2 decades and >200 trials for cardiovascular disease have revealed that most cell types are safe; however, their efficacy remains controversial, limiting the transition of this therapy from investigation to practice. Lessons learned from these initial studies are driving the design of new clinical trials; higher fidelity of cell isolation techniques, standardization of conditions, more consistent use of state of the art measurement techniques, and assessment of multiple end points to garner insights into the efficacy of stem cells. Translation to clinical trials has almost outpaced our mechanistic understanding, and individual patient factors likely play a large role in stem cell efficacy. Therefore, careful analysis of dosing, delivery methods, and the ideal patient populations is necessary to translate cell therapy from research to practice. We are at a pivotal stage in the field in which information from many relatively small clinical trials must guide carefully executed efficacy trials. Larger efficacy trials are being launched to answer questions about older, first-generation stem cell therapeutics, while novel, second-generation products are being introduced into the clinical realm. This review critically examines the current state of clinical research on cell-based therapies for cardiovascular disease, highlighting the controversies in the field, improvements in clinical trial design, and the application of exciting new cell products.

Cardiac resynchronization therapy in patients with heart failure and moderately reduced ejection fraction: Could it trigger a super-response?

Background/Aim

Despite the well-established benefits of cardiac resynchronization therapy (CRT) in heart failure (HF) patients with left ventricular ejection fraction (LVEF) ≤35%, many patients with less reduced EF remain refractory to optimized medical treatment and at high risk of morbidity and mortality. The objective of the study is to evaluate the effects of CRT in optimally treated patients with New York Heart Association (NYHA) classes II–IV, LVEF of 36–45%, and left bundle branch (LBBB), including clinical, structural and biochemical response.

Methods

A selected group of HF patients have been implanted with CRT-P devices and were followed up for 6 months at 4, 12 and 24 weeks. Clinical assessment included NYHA class, quality of life and 6-min walk distance (6 MWD) test. Echocardiographic assessment included LV dimensions and function and left atrial volume. Serum N-terminal pro b-type natriuretic peptide (NT-ProBNP) was measured at the same intervals.

Results

This prospective single center study included 23 patients. NYHA functional class significantly improved after CRT-P (p < 0.0001), associated with improvement in QOL (p < 0.0001) and 6 MWD, which increased, from 145.7 ± 20.1 m to 219.5 ± 42.2 m (p < 0.0001). Mean QRS duration showed significant shortening from 164.4 ± 13.2 ms to 126.4 ± 13.6 ms (p < 0.0001). CRT induced reverse remodeling with reduction in both left ventricular end diastolic diameter (LVEDD) from 68.95 ± 5.05 mm to 62.8 ± 4.47 mm, p = 0.0002 and left ventricular end systolic diameter (LVESD) from 54.1 ± 4.5 mm to 46.5 ± 4.1 mm, p < 0.0001, and significant increase in LVEF (from 40.3 ± 2.8 to 48.3 ± 4.2 mm, p < 0.0001). The biochemical response to CRT showed significant reduction in serum NT-ProBNP from 1025.6 ± 363.1 pg/ml to 594.9 ± 263.5 pg/ml (p < 0.0001).

Conclusions

Symptomatic HF patients on maximal optimized medical treatment who have LBBB and baseline LVEF 35–45% appeared to derive significant clinical and structural benefit from CRT.

Relation between therapy-induced changes in natriuretic peptide levels and long-term therapeutic effects on mortality in patients with heart failure and reduced ejection fraction

AIMS

To assess whether natriuretic peptides (NPs) can be used to reliably predict long-term therapeutic effect on clinical outcomes for patients with heart failure and reduced ejection fraction (HFrEF).

METHODS AND RESULTS

HFrEF intervention trials with mortality data were identified. Subsequently, we identified trials assessing therapy-induced changes in NPs. We assessed the correlation between the average short-term placebo-corrected drug or device effect on NPs and the longer-term therapeutic effect on clinical outcomes. Of 35 distinct therapies with an identifiable mortality result (n = 105 062 patients), 20 therapies had corresponding data on therapeutic effect on NPs. No correlation was observed between therapy-induced placebo-corrected change in brain natriuretic peptide or N-terminal pro-brain natriuretic peptide and therapeutic effect on all-cause mortality (ACM) (Spearman r = -0.32, P = 0.18 and r = -0.20, P = 0.47, respectively). There was no correlation between therapy-induced placebo-corrected per cent change in NP and intervention effect on ACM or ACM-heart failure hospitalizations (r = -0.30, P = 0.11 and r = 0.10, P = 0.75, respectively).

CONCLUSIONS

Short-term intervention-induced changes in NP levels are not reliable predictors of therapeutic long-term effect on mortality or morbidity outcomes for patients with HFrEF.

Six-minute walk distance after coronary artery bypass grafting compared with medical therapy in ischaemic cardiomyopathy

Background

In patients with ischaemic left ventricular dysfunction, coronary artery bypass surgery (CABG) may decrease mortality, but it is not known whether CABG improves functional capacity.

Objective

To determine whether CABG compared with medical therapy alone (MED) increases 6 min walk distance in patients with ischaemic left ventricular dysfunction and coronary artery disease amenable to revascularisation.

Methods

The Surgical Treatment in Ischemic Heart disease trial randomised 1212 patients with ischaemic left ventricular dysfunction to CABG or MED. A 6 min walk distance test was performed both at baseline and at least one follow-up assessment at 4, 12, 24 and/or 36 months in 409 patients randomised to CABG and 466 to MED. Change in 6 min walk distance between baseline and follow-up were compared by treatment allocation.

Results

6 min walk distance at baseline for CABG was mean 340±117 m and for MED 339±118 m. Change in walk distance from baseline was similar for CABG and MED groups at 4 months (mean +38 vs +28 m), 12 months (+47 vs +36 m), 24 months (+31 vs +34 m) and 36 months (-7 vs +7 m), P>0.10 for all. Change in walk distance between CABG and MED groups over all assessments was also similar after adjusting for covariates and imputation for missing values (+8 m, 95% CI -7 to 23 m, P=0.29). Results were consistent for subgroups defined by angina, New York Heart Association class ≥3, left ventricular ejection fraction, baseline walk distance and geographic region.

Conclusion

In patients with ischaemic left ventricular dysfunction CABG compared with MED alone is known to reduce mortality but is unlikely to result in a clinically significant improvement in functional capacity.

Trial registration number

NCT00023595.

Impact of cardiac resynchronization therapy on inflammatory biomarkers and cardiac remodeling: The paradox of functional and echocardiographic response

INTRODUCTION

Response to cardiac resynchronization therapy (CRT) can currently be assessed by clinical or echocardiographic criteria, and there is no strong evidence supporting the use of one rather than the other. Reductions in B-type natriuretic peptide (BNP) and C-reactive protein (CRP) have been shown to be associated with CRT response. This study aims to assess variation in BNP and CRP six months after CRT and to correlate this variation with criteria of functional and echocardiographic response.

METHODS

Patients undergoing CRT were prospectively enrolled between 2011 and 2014. CRT response was defined by echocardiography (15% reduction in left ventricular end-systolic volume) and by cardiopulmonary exercise testing (10% increase in peak oxygen consumption) from baseline to six months after device implantation.

RESULTS

A total of 115 patients were enrolled (68.7% male, mean age 68.6±10.5 years). Echocardiographic response was seen in 51.4% and 59.2% were functional responders. There was no statistical correlation between the two. Functional response was associated with a significantly greater reduction in BNP (-167.6±264.1 vs. -24.9±269.4 pg/ml; p=0.044) and CRP levels (-1.6±4.4 vs. 2.4±9.9 mg/l; p=0.04). Nonetheless, a non-significant reduction in BNP and CRP was observed in echocardiographic responders (BNP -144.7±260.2 vs. -66.1±538.2 pg/ml and CRP -7.1±24.3 vs. 0.8±10.3 mg/l; p>0.05).

CONCLUSION

An increase in exercise capacity after CRT implantation is associated with improvement in myocardial remodeling and inflammatory biomarkers. This finding highlights the importance of improvement in functional capacity after CRT implantation, not commonly considered a criterion of CRT response.

Natriuretic Peptides as Biomarkers of Treatment Response in Clinical Trials of Heart Failure

OBJECTIVES

This study sought to determine whether treatment-related changes in natriuretic peptides (NPs) predict longer-term therapeutic effects in clinical trials of heart failure (HF).

BACKGROUND

The lack of reliable predictors of efficacy of drugs and devices in HF has presented a major hurdle to the development and evaluation of novel therapies.

METHODS

The study conducted a trial-level analysis of 16 phase III chronic HF trials completed between 1987 and 2013 studying 18 therapeutic comparisons in 48,844 patients. Weighted Pearson correlation coefficients were calculated between average control- or placebo-corrected changes in NPs and longer-term treatment effects on clinical endpoints (expressed as log-transformed hazard ratios).

RESULTS

Median follow-up for clinical endpoints was 28 (25th to 75th percentile range: 18 to 36) months. NPs were available in a median of 748 (25th to 75th percentile range: 270 to 1,868) patients and measured at a median of 4 (25th to 75th percentile range: 3 to 6) months after randomization. Treatment-related changes in NPs were not correlated with longer-term treatment effects on all-cause mortality (r = 0.12; p = 0.63), but were correlated with HF hospitalization (r = 0.63; p = 0.008). Correlation with HF hospitalization improved when analyses were restricted to trials completed in the last decade (>2010; r = 0.92; p = 0.0095), using N-terminal pro-B-type NP assays (r = 0.65; p = 0.06), and evaluating inhibitors of the renin-angiotensin-aldosterone system (r = 0.97; p = 0.0002).

CONCLUSIONS

When examining a broad range of interventions, therapy-related changes in NPs appeared modestly correlated with longer-term therapeutic effects on hospitalization for HF, but not with effects on all-cause mortality. These observations raise important caveats regarding the use of NPs in phase II trials for decision making regarding phase III trials.

Prognostic Implications of Changes in N-Terminal Pro-B-Type Natriuretic Peptide in Patients With Heart Failure

BACKGROUND

Natriuretic peptides (NP) have prognostic value in heart failure (HF), although the clinical importance of changes in NP from baseline is unclear.

OBJECTIVES

The authors assessed whether a reduction in N-terminal pro-B-type NP (NT-proBNP) was associated with a decrease in HF hospitalization and cardiovascular mortality (primary endpoint) in patients with HF and reduced ejection fraction, whether treatment with sacubitril/valsartan reduced NT-proBNP below specific partition values more than enalapril, and whether the relationship between changes in NT-proBNP and changes in the primary endpoint were dependent on assigned treatment.

METHODS

In PARADIGM-HF (Prospective Comparison of ARNI [Angiotensin Receptor-Neprilysin Inhibitor] with ACEI [Angiotensin-Converting-Enzyme Inhibitor] to Determine Impact on Global Mortality and Morbidity in Heart Failure Trial), baseline NT-proBNP was measured in 2,080 patients; 1,292 had baseline values >1,000 pg/ml and were reassessed at 1 and 8 months. We related change in NT-proBNP to outcomes.

RESULTS

One month after randomization, 24% of the baseline NT-proBNP levels >1,000 pg/ml had fallen to ≤1,000 pg/ml. Risk of the primary endpoint was 59% lower in patients with a fall in NT-proBNP to ≤1,000 pg/ml than in those without such a fall. In sacubitril/valsartan-treated patients, median NT-proBNP was significantly lower 1 month after randomization than in enalapril-treated patients, and it fell to ≤1,000 pg/ml in 31% versus 17% of patients treated with sacubitril/valsartan and enalapril, respectively. There was no significant interaction between treatment and the relationship between change in NT-proBNP and the subsequent risk of the primary endpoint.

CONCLUSIONS

Patients who attained a significant reduction in NT-proBNP had a lower subsequent rate of cardiovascular death or HF hospitalization independent of the treatment group. Treatment with sacubitril/valsartan was nearly twice as likely as enalapril to reduce NT-proBNP to values ≤1,000 pg/ml. (Prospective Comparison of ARNI [Angiotensin Receptor-Neprilysin Inhibitor] with ACEI [Angiotensin-Converting-Enzyme Inhibitor] to Determine Impact on Global Mortality and Morbidity in Heart Failure Trial) [PARADIGM-HF]; NCT01035255.).

Natriuretic Peptides, 6-Min Walk Test, and Quality-of-Life Questionnaires as Clinically Meaningful Endpoints in HF Trials

The Expedited Access for Premarket Approval and De Novo Medical Devices Intended for Unmet Medical Need for Life Threatening or Irreversibly Debilitating Diseases or Conditions document was issued as a guidance for industry and for the Food and Drug Administration. The Expedited Access Pathway was designed as a new program for medical devices that demonstrated the potential to address unmet medical needs for life threatening or irreversibly debilitating conditions. The Food and Drug Administration would consider assessments of a device's effect on intermediate endpoints that, when improving in a congruent fashion, are reasonably likely to predict clinical benefit. The purpose of this review is to provide evidence to support the use of 3 such intermediate endpoints: natriuretic peptides, such as N-terminal pro-B-type natriuretic peptide/B-type natriuretic peptide, the 6-min walk test distance, and health-related quality of life in heart failure.

ANMCO/ELAS/SIBioC Consensus Document: biomarkers in heart failure

Biomarkers have dramatically impacted the way heart failure (HF) patients are evaluated and managed. A biomarker is a characteristic that is objectively measured and evaluated as an indicator of normal biological or pathogenic processes, or pharmacological responses to a therapeutic intervention. Natriuretic peptides [B-type natriuretic peptide (BNP) and N-terminal proBNP] are the gold standard biomarkers in determining the diagnosis and prognosis of HF, and a natriuretic peptide-guided HF management looks promising. In the last few years, an array of additional biomarkers has emerged, each reflecting different pathophysiological processes in the development and progression of HF: myocardial insult, inflammation, fibrosis, and remodelling, but their role in the clinical care of the patient is still partially defined and more studies are needed before to be well validated. Moreover, several new biomarkers have the potential to identify patients with early renal dysfunction and appear to have promise to help the management cardio-renal syndrome. With different biomarkers reflecting HF presence, the various pathways involved in its progression, as well as identifying unique treatment options for HF management, a closer cardiologist-laboratory link, with a multi-biomarker approach to the HF patient, is not far ahead, allowing the unique opportunity for specifically tailoring care to the individual pathological phenotype.

Established and Emerging Roles of Biomarkers in Heart Failure Clinical Trials

The role of circulating biomarkers in heart failure clinical trials has evolved in recent decades. Increasing evidence behind the use of natriuretic peptides, emergence of novel biomarkers, and increased emphasis on targeting therapies toward physiological basis of disease (so-called precision medicine) have all contributed to the continued expansion of biomarker use in heart failure clinical trials. We will explore the advantages and pitfalls encountered through the use of biomarkers in clinical trials as an inclusion criterion, toxicity marker, and end point. We will also review their role in providing insights into the mechanism of action of therapeutics and guiding therapy in the management of patients with heart failure.

Cardiopulmonary Exercise Testing in Heart Failure

Exercise intolerance, indicated by dyspnea and fatigue during exertion, is a cardinal manifestation of heart failure (HF). Cardiopulmonary exercise testing (CPET) precisely defines maximum exercise capacity through measurement of peak oxygen uptake (VO2). Peak VO2 values have a critical role in informing patient selection for advanced HF interventions such as heart transplantation and ventricular assist devices. Oxygen uptake and ventilatory patterns obtained during the submaximal portion of CPET are also valuable to recognize because of their ease of ascertainment during low-level exercise, relevance to ability to perform activities of daily living, independence from volitional effort, and strong relationship to prognosis in HF. The ability of peak VO2 and other CPET variables to be measured reproducibly and to accurately reflect HF severity is increasingly recognized and endorsed by scientific statements. Integration of CPET with invasive hemodynamic monitoring and cardiac imaging during exercise provides comprehensive characterization of multisystem reserve capacity that can inform prognosis and the need for cardiac interventions. Here, we review both practical aspects of conducting CPETs in patients with HF for clinical and research purposes as well as interpretation of gas exchange patterns across the spectrum of preclinical HF to advanced HF.

Trends in Utilization of Surrogate Endpoints in Contemporary Cardiovascular Clinical Trials

Surrogate endpoints facilitate trial efficiency but are variably linked to clinical outcomes, and limited data are available exploring their utilization in cardiovascular clinical trials over time. We abstracted data regarding primary clinical, intermediate, and surrogate endpoints from all phase II to IV cardiovascular clinical trials from 2001 to 2012 published in the 8 highest Web of Science impact factor journals. Two investigators independently classified the type of primary endpoint. Of the 1,224 trials evaluated, 677 (55.3%) primary endpoints were clinical, 165 (13.5%) intermediate, and 382 (31.2%) surrogate. The relative proportions of these endpoints remained constant over time (p = 0.98). Trials using surrogate endpoints were smaller (187 vs 1,028 patients) and enrolled patients more expeditiously (1.4 vs 0.9 patients per site per month) compared with trials using clinical endpoints (p <0.001 for both comparisons). Surrogate endpoint trials were independently more likely to meet their primary endpoint compared to trials with clinical endpoints (adjusted odds ratio 1.56, 95% CI 1.05 to 2.34; p = 0.03). Rates of positive results in clinical endpoint trials have decreased over time from 66.1% in 2001 to 2003 to 47.2% in 2010 to 2012 (p = 0.001), whereas these rates have remained stable over the same period for surrogate (72.0% to 69.3%, p = 0.27) and intermediate endpoints (74.4% to 71.4%, p = 0.98). In conclusion, approximately a third of contemporary cardiovascular trials use surrogate endpoints. These trials are completed more expeditiously and are more likely to meet their primary outcomes. The overall scientific contribution of these surrogate endpoint trials requires further attention given their variable association with definitive outcomes.

Trends in characteristics of cardiovascular clinical trials 2001-2012

BACKGROUND

Efficient conduct of clinical trials is essential for the timely generation of critical medical knowledge.

METHODS

We systematically assessed size, duration, enrollment rates, and geographic distribution of randomized cardiovascular trials published between 2001 and 2012 in the 8 highest-impact journals in general medicine and cardiology.

RESULTS

Of the 1,224 trials, 27.0% were conducted in North America, 36.5% in Western Europe, and 7.7% in other countries, and 28.8% were multiregional. Trials enrolled a median of 452 patients (interquartile range 167-1,530) in 20 sites (2-76). Median duration was 2.1 (1.3-3.3) years, with an estimated enrollment rate of 1.1 (0.5-3.5) patients/site per month. Between 2001-2003 and 2009-2012, the proportion of North American trials decreased from 34.5% to 25.7% (P = .006), whereas that of multiregional trials (from 26.0% to 30.3%; P = .046) and trials conducted in other countries (from 4.6% to 10.3%; P = .012) increased. Over time, trials involved more patients (from 400 to 500 [median]; P = .032) and sites (from 20 to 22; P = .049), multiregional trials involved more countries (from 12 to 18; P = .031), and enrollment rate declined from 1.2 to 0.9 patients/site per month (P = .017). The proportion of trials meeting their primary end point ("positive") decreased from 69% to 57% (P < .001). Trials with higher enrollment rates were more likely to be positive (odds ratio 1.20 per doubling, 95% CI 1.12-1.29), as were industry-sponsored compared with government-sponsored trials (odds ratio 2.62, 95% CI 1.67-4.12).

CONCLUSIONS

From 2001 to 2012, cardiovascular clinical trials have become larger, more global, and less likely to meet their primary end point. Enrollment rates have declined, requiring more sites and regions.

Reduction of lymphocyte G protein-coupled receptor kinase-2 (GRK2) after exercise training predicts survival in patients with heart failure

BACKGROUND

Increased cardiac G protein-coupled receptor kinase-2 (GRK2) expression has a pivotal role at inducing heart failure (HF)-related β-adrenergic receptor (βAR) dysfunction. Importantly, abnormalities of βAR signalling in the failing heart, including GRK2 overexpression, are mirrored in circulating lymphocytes and correlate with HF severity. Exercise training has been shown to exert several beneficial effects on the failing heart, including normalization of cardiac βAR function and GRK2 protein levels. In the present study, we evaluated whether lymphocyte GRK2 levels and short-term changes of this kinase after an exercise training programme can predict long-term survival in HF patients.

METHODS

For this purpose, we prospectively studied 193 HF patients who underwent a 3-month exercise training programme. Lymphocyte GRK2 protein levels, plasma N-terminal pro-brain natriuretic peptide, and norepinephrine were measured at baseline and after training along with clinical and functional parameters (left ventricular ejection fraction, NYHA class, and peak-VO2). Cardiac-related mortality was evaluated during a mean follow-up period of 37 ± 20 months.

RESULTS

Exercise was associated with a significant reduction of lymphocyte GRK2 protein levels (from 1.29 ± 0.52 to 1.16 ± 0.65 densitometric units, p < 0.0001). Importantly, exercise related changes of GRK2 (delta values) robustly predicted survival in our study population. Interestingly, HF patients who did not show reduced lymphocyte GRK2 protein levels after training presented the poorest outcome.

CONCLUSIONS

Our data offer the first demonstration that changes of lymphocyte GRK2 after exercise training can strongly predict outcome in advanced HF.

Impact of mineralocorticoid receptor antagonists on changes in cardiac structure and function of left ventricular dysfunction: a meta-analysis of randomized controlled trials

BACKGROUND

A comprehensive evaluation of the benefits of mineralocorticoid receptor antagonists on cardiac remodeling is lacking. We aimed to evaluate the impact of mineralocorticoid receptor antagonists on changes in cardiac structure and function of left ventricular dysfunction.

METHODS AND RESULTS

Articles were identified by online searches in PubMed, EMBASE, Cochrane, and ClinicalTrials.gov databases before June 2012, by hand searches of reviews and relevant journals, and by contact with the authors. Qualified articles were restricted to randomized controlled trials. There were, respectively, 12, 4, and 3 qualified trials that randomized 572, 647, and 407 patients to spironolactone, canrenoate, and eplerenone, and 531, 655, and 395 patients to placebo or active treatment, respectively. Overall, under mineralocorticoid receptor antagonist treatment there was improvement in left ventricular ejection fraction (weighted mean difference, 2.97; 95% confidence interval [95% CI], 2.26-3.67; P<0.0005), left ventricular end-systolic and end-diastolic volume index (weighted mean difference, -5.64; 95% CI, -7.94 to -3.34; P<0.0005 and weighted mean difference, -7.46; 95% CI, -11.63 to -3.3; P<0.0005), serum amino-terminal peptide of procollagen type-III (weighted mean difference, -1.12; 95% CI, -1.49 to -0.74; P<0.0005), B-type natriuretic peptide (weighted mean difference, -67.06; 95% CI, -91.24 to -42.88; P<0.0005), peak velocities of early mitral inflow (E; weighted mean difference, -9.57; 95% CI, -12.98 to -6.17; P<0.0005), and E wave deceleration time (weighted mean difference, 7.08; 95% CI, 4.07-10.09; P<0.0005). There was low probability of heterogeneity and publication bias.

CONCLUSIONS

Our findings demonstrate that mineralocorticoid receptor antagonist treatment may exert beneficial effects on the reversal of cardiac remodeling and improvement of left ventricular function.

Endothelial dysfunction, arterial stiffness, and heart failure

Outcomes for heart failure (HF) patients remain suboptimal. No known therapy improves mortality in acute HF and HF with preserved ejection fraction; the most recent HF trial results have been negative or neutral. Improvement in surrogate markers has not necessarily translated into better outcomes. To translate breakthroughs with potential therapies into clinical benefit, a better understanding of the pathophysiology establishing the foundation of benefit is necessary. Vascular function plays a central role in the development and progression of HF. Endothelial function and nitric oxide availability affect myocardial function, systemic and pulmonary hemodynamics, and coronary and renal circulation. Arterial stiffness modulates ventricular loading conditions and diastolic function, key components of HF with preserved ejection. Endothelial function and arterial stiffness may therefore serve as important physiological targets for new HF therapies and facilitate patient selection for improved application of existing agents.

Circulation: Heart Failure Editors’ Picks

The following are highlights from Circulation: Heart Failure Topic Review. This series summarizes the most important articles, as selected by the editors, that have been published in the Circulation portfolio. The objective of this series is to provide our readership with a timely comprehensive selection of important articles that are relevant to the heart failure audience. The studies included in this article represent the most noteworthy research in the areas of heart failure and therapeutics.