Chronic kidney disease and cardiac remodelling in patients with mild heart failure: results from the REsynchronization reVErses Remodeling in Systolic Left vEntricular Dysfunction (REVERSE) study

Fibulin7 Mediated Pathological Cardiac Remodeling through EGFR Binding and EGFR-Dependent FAK/AKT Signaling Activation

Adverse remodeling after myocardial infarction (MI) result in heart failure and sudden cardiac death. Fibulin7 (FBLN7) is an adhesion protein excreted into the extracellular matrix that functions in multiple biological processes. However, whether and how FBLN7 affects post-MI cardiac remodeling remains unclear. Here, the authors identify FBLN7 as a critical profibrotic regulator of adverse cardiac remodeling. They observe significantly upregulated serum FBLN7 levels in MI patients with left ventricular remodeling compared to those without MI. Microarray dataset analysis reveal FBLN7 is upregulated in human heart samples from patients with dilated and hypertrophic cardiomyopathy compared with non-failing hearts. The authors demonstrate that FBLN7 deletion attenuated post-MI cardiac remodeling, leading to better cardiac function and reduced myocardial fibrosis, whereas overexpression of FBLN7 results in the opposite effects. Mechanistically, FBLN7 binds to the epidermal growth factor receptor (EGFR) through its EGF-like domain, together with the EGF-like calcium-binding domain, and induces EGFR autophosphorylation at tyrosine (Y) 1068 and Y1173, which activates downstream focal adhesion kinase/AKT signaling, thereby leading to fibroblast-to-myofibroblast transdifferentiation. In addition, FBLN7-EGFR mediates this signal transduction, and the fibrotic response is effectively suppressed by the inhibition of EGFR activity. Taken together, FBLN7 plays an important role in cardiac remodeling and fibrosis after MI.

Clinical implications and risk factors for QRS prolongation over time in heart failure patients

BACKGROUND

QRS prolongation is an established prognostic marker in heart failure (HF). In contrast, the role of QRS width progression over time has been incompletely explored. The current study investigates the role of QRS width progression over time on clinical status and identifies underlying predictors.

METHODS

Datasets of ≥ 2 consecutive visits from 100 attendees to our HF clinic between April and August 2021 were analysed for changes in QRS complex duration.

RESULTS

In total 240 datasets were stratified into tertiles based on change in QRS duration (mm/month) (1st tertile: - 1.65 [1.50] 'regression'; 2nd tertile 0.03 [0.19] 'stable', 3rd tertile 3.57 [10.11] 'progression'). The incidence of the combined endpoint HF hospitalisation and worsening of symptomatic heart failure was significantly higher in the group with QRS width progression (3rd tertile) compared with the stable group (2nd tertile; log-rank test: p = 0.013). These patients were characterised by higher plasma NT-pro-BNP levels (p = 0.008) and higher heart rate (p = 0.007). A spline-based prediction model identified patients at risk of QRS width progression when NT-pro-BNP and heartrate were > 837 pg/ml and > 83/bpm, respectively. These markers were independent of guideline-directed medical HF therapy. Patients beyond both thresholds had a 14-fold increased risk of QRS width progression compared to those with neither or either alone (HR: 14.2 [95% 6.9 - 53.6]; p < 0.0001, p for interaction = 0.016).

CONCLUSIONS

This pilot study demonstrates that QRS width progression is associated with clinical deterioration of HF. NTproBNP plasma levels and heart rate indicate patients at risk QRS width progression, independently of HF therapy.

Characteristics and complications of fracture in older adults with chronic kidney disease: a cross-sectional study

Background

The aim of this study was to analyze the clinical characteristics of older fracture patients with chronic kidney disease (CKD) and to determine the risk factors of perioperative cardiovascular complications.

Methods

We retrospectively reviewed clinical data of older fracture patients with CKD admitted to the Third Hospital of Hebei Medical University from January 2016 to October 2021. The data we collected included baseline characteristics and complications. We finally determined the risk factors of perioperative cardiovascular complications by using logistic regression.

Results

We ended up enrolling 224 patients, and there were 91 (40.6%) males and 133 (59.4%) females, with a median age of 79 years. 80–84 years old was the age group with high incidence of fracture. The majority of fracture occurred indoors (130 cases, 58.0%) and morning (98 cases, 43.8%). Hip fracture was most common (183 cases, 81.7%), of which femoral neck fracture (101 cases, 45.0%) was the most prevalent. The most common comorbid condition was hypertension (171 cases, 76.3%), and anemia was the most common complication (148 cases, 66.1%). Age ≥ 80 years (OR = 2.023, 95% CI 1.110–3.688), previously combined with cardiovascular calcification (OR = 1.901, 95% CI 1.047–3.451) and admission hemoglobin level < 100 g/L (OR = 3.191, 95% CI 1.744–5.838) were independent risk factors of perioperative cardiovascular disease (CVD).

Conclusion

It was especially necessary to enhance fracture prevention for CKD. Patients whose age older than 80, hemoglobin less than 100 g/L on admission and have previous cardiovascular calcification are more likely to develop perioperative CVD. Such patients require reasonable decisions during the perioperative period to avoid the occurrence of CVD.

Renal function in patients with significant tricuspid regurgitation: pathophysiological mechanisms and prognostic implications

BACKGROUND

The pathophysiological mechanisms linking tricuspid regurgitation (TR) and chronic kidney disease (CKD) remain unknown. This study aimed to determine which pathophysiological mechanisms related to TR are independently associated with renal dysfunction and to evaluate the impact of renal impairment on long-term prognosis in patients with significant (≥ moderate) secondary TR.

METHODS

A total of 1234 individuals (72 [IQR 63-78] years, 50% male) with significant secondary TR were followed up for the occurrence of all-cause mortality and the presence of significant renal impairment (eGFR of <60 mL min-1  1.73 m-2 ) at the time of baseline echocardiography.

RESULTS

Multivariable analysis demonstrated that severe right ventricular (RV) dysfunction (TAPSE < 14 mm) was independently associated with the presence of significant renal impairment (OR 1.49, 95% CI 1.11 to 1.99, P = 0.008). Worse renal function was associated with a significant reduction in survival at 1 and 5 years (85% vs. 87% vs. 68% vs. 58% at 1 year, and 72% vs. 64% vs. 39% vs. 19% at 5 years, for stage 1, 2, 3 and 4-5 CKD groups, respectively, P < 0.001). The presence of severe RV dysfunction was associated with reduced overall survival in stage 1-3 CKD groups, but not in stage 4-5 CKD groups.

CONCLUSIONS

Of the pathophysiological mechanisms identified by echocardiography that are associated with significant secondary TR, only severe RV dysfunction was independently associated with the presence of significant renal impairment. In addition, worse renal function according to CKD group was associated with a significant reduction in survival.

Renal denervation prevents myocardial structural remodeling and arrhythmogenicity in a chronic kidney disease rabbit model

BACKGROUND

The electrophysiological (EP) effects and safety of renal artery denervation (RDN) in chronic kidney disease (CKD) are unclear.

OBJECTIVE

The purpose of this study was to investigate the arrhythmogenicity of RDN in a rabbit model of CKD.

METHODS

Eighteen New Zealand white rabbits were randomized to control (n = 6), CKD (n = 6), and CKD-RDN (n = 6) groups. A 5/6 nephrectomy was selected for the CKD model. RDN was applied in the CKD-RDN group. All rabbits underwent cardiac EP studies for evaluation. Immunohistochemistry, myocardial fibrosis, and renal catecholamine levels were evaluated.

RESULTS

The CKD group (34.8% ± 9.2%) had a significantly higher ventricular arrhythmia (VA) inducibility than the control (8.6% ± 3.8%; P <.01) and CKD-RDN (19.5% ± 6.3%; P = .01) groups. In the CKD-RDN group, ventricular fibrosis was significantly decreased compared to the CKD group (7.4% ± 2.0 % vs 10.4% ± 3.7%; P = .02). Sympathetic innervation in the CKD group was significantly increased compared to the control and CKD-RDN groups [left ventricle: 4.1 ± 1.8 vs 0.8 ± 0.5 (10² μm²/mm²), P <.01; 4.1 ± 1.8 vs 0.9± 0.6 (10² μm²/mm²), P <.01; right ventricle: 3.6 ± 1.0 vs 1.0 ± 0.4 (10² μm²/mm²), P <.01; 3.6 ± 1.0 vs 1.0 ± 0.5 (10² μm²/mm²), P <.01].

CONCLUSION

Neuromodulation by RDN demonstrated protective effects with less structural and electrical remodeling, leading to attenuated VAs. In a rabbit model of CKD, RDN plays a therapeutic role by lowering the risk of VA caused by autonomic dysfunction.

Incidence and Risk Factors for Permanent Pacemaker Implantation Following Mitral or Aortic Valve Surgery

BACKGROUND

Risk factors for post-operative conduction disturbances after cardiac valve surgery requiring a permanent pacemaker (PPM) are poorly characterized.

OBJECTIVES

The aim of this study was to investigate the timing and risk factors for PPM implantation after mitral or aortic valve surgery.

METHODS

All patients who underwent open aortic or mitral valve surgery between January 1996 and December 2014 were reviewed using New York State's mandatory hospital discharge database. Patients with prior cardiac surgery or pre-existing PPM were excluded. The primary endpoint was PPM implantation within 1 year.

RESULTS

Among 77,882 patients, 63.8% (n = 49,706) underwent aortic valve replacement (AVR), 18.9% (n = 14,686) underwent mitral valve replacement (MVR), 10.5% (n = 8,219) underwent mitral valve repair (MVr), 5.4% (n = 4,202) underwent AVR plus MVR, and 1.4% (n = 1,069) underwent AVR plus MVr. The 1-year PPM implantation rate was 4.5% after MVr, 6.6% after AVR, 9.3% after AVR plus MVr, 10.5% after MVR, and 13.3% after AVR plus MVR (p < 0.001). Across all groups, the majority of PPMs were implanted during the index hospitalization (79.9%). MVr was associated with the lowest risk for PPM and AVR plus MVR with the highest risk. Older age, history of arrhythmias, pre-operative conduction disturbances, and concomitant index procedures were associated with increased risk for PPM during the index hospitalization. Conversely, beyond 30 days, chronic comorbidities were associated with increased risk for PPM.

CONCLUSIONS

Conduction disturbances requiring PPM remain a common adverse event after valve surgery. Identifying patients at risk for PPM will help facilitate perioperative planning and inform clinical decision making regarding post-operative rhythm surveillance.

Effect of Diabetes Mellitus on Cardiac Resynchronization Therapy and to Prognosis in Heart Failure (from the Prospective Evaluation of Asian With Cardiac Resynchronization Therapy for Heart Failure Study)

The association of diabetes mellitus (DM) with cardiac resynchronization therapy (CRT) response and cardiovascular outcomes in Asian patients with heart failure (HF) is unclear. This study aims to investigate the effects of DM on CRT response and cardiovascular outcomes in Asian HF patients. Consecutive Asian HF patients receiving CRT were enrolled in the Prospective Evaluation of Asian with CRT for Heart Failure (PEACH) study from 2011 to 2017. CRT response and super-response were defined as decrease in end-systolic volume index ≥15% and ≥30%, respectively. Primary endpoint was time to composite of HF-hospitalization and all-cause mortality. Among 161 patients followed for 3.3 ± 1.5 years (age 66.7 ± 11.2 years, 22% females, mean QRS duration 154.3 ± 22.4 ms, 83% left bundle branch block), 84 (52%) were CRT responders and 57 (35%) were super-responders. Of 82 (51%) patients with DM (100% type 2, mean HbA1c 7.3 ± 1.9%), 35 (43%) were responders. DM attenuated reverse remodeling (CRT response: AOR 0.44, 95% confidence interval [CI] 0.20 to 0.98, p < 0.05; super-response: AOR 0.42, 95% CI 0.18 to 0.97, p <0.05), and DM increased HF-hospitalization and all-cause mortality (AHR 1.68, 95% CI 1.00 to 2.82, p = 0.05). The extent of CRT-response correlates with higher event-free survival (CRT response: AHR 0.5, 95% CI 0.30 to 0.81, p = 0.005; super-response: AHR 0.27, 95% CI 0.14 to 0.52, p < 0.001). In conclusion, the extent of reverse remodeling post-CRT is the strongest predictor of event free survival. However, DM is detrimental to the CRT recipient by attenuating reverse remodeling, inducing end organ dysfunction and is independently associated with worsened clinical outcomes among Asian HF patients.

The Role of Fibroblast Growth Factor 23 in Inflammation and Anemia

In patients with chronic kidney disease (CKD), adverse outcomes such as systemic inflammation and anemia are contributing pathologies which increase the risks for cardiovascular mortality. Amongst these complications, abnormalities in mineral metabolism and the metabolic milieu are associated with chronic inflammation and iron dysregulation, and fibroblast growth factor 23 (FGF23) is a risk factor in this context. FGF23 is a bone-derived hormone that is essential for regulating vitamin D and phosphate homeostasis. In the early stages of CKD, serum FGF23 levels rise 1000-fold above normal values in an attempt to maintain normal phosphate levels. Despite this compensatory action, clinical CKD studies have demonstrated powerful and dose-dependent associations between FGF23 levels and higher risks for mortality. A prospective pathomechanism coupling elevated serum FGF23 levels with CKD-associated anemia and cardiovascular injury is its strong association with chronic inflammation. In this review, we will examine the current experimental and clinical evidence regarding the role of FGF23 in renal physiology as well as in the pathophysiology of CKD with an emphasis on chronic inflammation and anemia.

T Cells Play a Causal Role in Diastolic Dysfunction during Uremic Cardiomyopathy

BACKGROUND

Uremic cardiomyopathy, characterized by left ventricular hypertrophy, diastolic dysfunction, and impaired myocardial strain, contributes to increased cardiovascular mortality in patients with CKD. Emerging evidence suggests a pathogenic role for T cells during chronic heart failure.

METHODS

To determine whether T cells contribute to uremic cardiomyopathy pathogenesis, we modeled this condition by inducing CKD via 5/6th nephrectomy in mice. We used flow cytometry to assess expression of markers of T cell memory or activation by lymphocytes from CKD mice and controls, as well as lymphocyte capacity for cytokine production. Flow cytometry was also used to quantify immune cells isolated from heart tissue. To test effects of T cell depletion on cardiac function, we gave CKD mice anti-CD3 antibody injections to deplete T cells and compared heart function (assessed by echocardiography) with that of controls. Finally, we correlated T cell phenotypes with structural and functional measures on clinically acquired echocardiograms in children with CKD.

RESULTS

Mice with CKD accumulated T cells bearing markers of memory differentiation (CD44hi) and activation (PD-1, KLRG1, OX40), as reported previously in human CKD. In addition, mice with CKD showed T cells infiltrating the heart. T cell depletion significantly improved both diastolic function and myocardial strain in CKD mice without altering hypertension or degree of renal dysfunction. In children with CKD, increasing frequency of T cells bearing activation markers PD-1 and/or CD57 was associated with worsening diastolic function on echocardiogram.

CONCLUSIONS

CKD results in an accumulation of proinflammatory T cells that appears to contribute to myocardial dysfunction.

Increasing sex differences in the use of cardiac resynchronization therapy with or without implantable cardioverter-defibrillator

Aims

Previous studies have identified sex disparities in the use of cardiac resynchronization therapy (CRT) and implantable cardioverter defibrillators (ICD), although the basis of underutilization in women remains poorly understood. The aim of this study was to assess sex differences in patterns of CRT use with our without ICD.

Methods and results

In this cross-sectional study using the National Inpatient Sample database we identified 311 009 patients undergoing CRT implantation in the United States between 2006 and 2012. Demographic and clinical characteristics were compared between men and women undergoing CRT implantation, with special attention to clinical predictors of left ventricular reverse remodelling (CRT response, score range: 0-4) and reduced ICD efficacy (score range: 0-7). When compared to men, women undergoing CRT implantation were significantly more likely to have ≥ 3 predictors of CRT response (47.3 vs. 33.2%, P < 0.001) and less likely to have ≥3 predictors of reduced ICD efficacy (27.0 vs. 37.3%, P < 0.001). Despite this, men were significantly more likely to undergo CRT with ICD (CRT-D) as the type of CRT (88.6 vs. 80.1% of all CRT implants). Compared to those with the greatest likelihood of CRT response (score ≥ 3), those with the least likelihood of CRT response had a significant decreased odds of CRT-D implant (adj odds ratio 0.27 [0.24-0.31], P < 0.001), with a greater decreased odds in women compared to men (P, for sex interaction <0.001). The difference in the % of CRT-D implant in men vs. women increased over the study period (P, sex Δ time trend = 0.012).

Conclusion

In this large, contemporary cohort, sex differences in CRT-D implantation were inversely related to predicted CRT efficacy and have increased over time. Future efforts to narrow the gap in CRT-D implantation in men and women may help better align device selection with those most likely to benefit.

Predictors of 1-Year Mortality After Transcatheter Aortic Valve Implantation in Patients With and Without Advanced Chronic Kidney Disease

Advanced chronic kidney disease (CKD) is an independent predictor of mortality in patients undergoing transcatheter aortic valve implantation (TAVI). We aimed to identify predictors of 1-year mortality in patients after TAVI stratified by the presence or absence of advanced CKD (defined as estimated glomerular filtration rate ≤30 ml/min/1.73 m² or permanent renal replacement therapy). Patients (n = 1204) from 10 centers in Europe, Japan, and Israel were included: 464 with and 740 without advanced CKD. Advanced CKD was associated with a 2-fold increase in the adjusted risk of 1-year all-cause death (p <0.001), and a 1.9-fold increase in cardiovascular death (p = 0.016). Interaction-term analysis was used to identify and compare independent predictors of 1-year mortality in both groups. Impaired left ventricular ejection fraction and poor functional class were predictive of death in the advanced CKD group (odds ratio [OR] 2.27, p = 0.002 and OR 3.87, p = 0.003, respectively) but not in patients without advanced CKD (p for interaction = 0.035 and 0.039, respectively), whereas bleeding was a predictor of mortality in the nonadvanced CKD group (OR 3.2, p = 0.005) but not in advanced CKD (p for interaction = 0.006). Atrial fibrillation was associated with a 2.2-fold increase (p = 0.032) in the risk of cardiovascular death in the advanced CKD group but not in the absence of advanced CKD (p for interaction = 0.022). In conclusion, the coexistence of advanced CKD and either reduced left ventricular ejection fraction or poor functional class has an incremental effect on the risk of death after TAVI. In contrast, bleeding had a greater effect on risk of death in patients without advanced CKD.

Multiple Comorbidities and Response to Cardiac Resynchronization Therapy: MADIT-CRT Long-Term Follow-Up

BACKGROUND

Data regarding cardiac resynchronization therapy (CRT) in patients with multiple comorbidities are limited.

OBJECTIVES

This study evaluated the association of multiple comorbidities with the benefits of CRT over implantable cardioverter-defibrillator (ICD) alone.

METHODS

We examined 1,214 MADIT-CRT (Multicenter Automatic Defibrillator Implantation Trial with Cardiac Resynchronization Therapy) study patients with left bundle branch block (LBBB) and 0, 1, 2, or ≥3 comorbidities, including renal dysfunction, hypertension (HTN), diabetes, coronary artery disease, history of atrial arrhythmias, history of ventricular arrhythmias, current smoking, and cerebrovascular accident. In an adjusted analysis, we analyzed risk of heart failure (HF) events or death by comorbidity group in all patients and in patients with CRT with defibrillator (CRT-D) versus ICD. Then we examined percent change in left ventricular (LV) end-diastolic volume, LV end-systolic volume, LV ejection fraction, left atrial volume, and LV dyssynchrony at 1-year in CRT-D patients by comorbidity group.

RESULTS

There was an inverse relationship between comorbidity burden and improvements in LV end-systolic volume, LV end-diastolic volume, left ventricular ejection fraction, left atrial volume, and LV dyssynchrony. In an adjusted model, there was an increasing risk of death or nonfatal HF events with increasing comorbidity burden regardless of treatment group (p < 0.001). During a mean follow-up of 4.65 years, there was no interaction with respect to comorbidity burden and the benefit of CRT-D versus ICD only for death or nonfatal HF events (interaction p = 0.943). In the groups with greatest comorbidity burden (2 and ≥3), the absolute risk reduction associated with CRT-D over ICD alone appeared greater than that seen for groups with less comorbidity burden (0 and 1).

CONCLUSIONS

During long-term follow-up of MADIT-CRT study patients with LBBB randomized to CRT-D, there were differences in HF or death risk and in the degree of reverse remodeling among comorbidity groups. However, the burden of comorbidity does not appear to compromise the clinical benefits of CRT-D compared with ICD alone.

Cardiac Resynchronization Therapy prevents progression of renal failure in heart failure patients

BACKGROUND

The goal of this study is to assess the effect of cardiac resynchronization therapy (CRT) over time on renal function and its impact on mortality. The effect of CRT on renal function in patients with heart failure is not well understood.

METHODS

All patients who underwent CRT implantation at University of Kansas between year 2000 and 2009 were reviewed and patients who had pre and post CRT renal function studied were included in our study. Stages of chronic kidney disease (CKD) were defined based on Kidney Disease Outcome Quality Initiative (KDOQI) guidelines. The effect of CRT on renal and cardiac function were studied at short term (≤6 months post implantation) and long term (>6 months).

RESULTS

A total of 588 patients with mean age of 67 ± 12 yrs were included in the study. CRT responders (defined by increase in LVEF ≥ 5%) were 54% during short term follow-up and 65% on long term follow-up. When compared to baseline, there was no significant deterioration in mean Glomerular Filtration Rate (GFR) during follow up. When analyzed based on the stages of CKD, there was significant improvement of renal function in patients with advanced kidney disease. Multivariate logistic regression analysis showed that stable GFR or an improvement in GFR independently predicted mortality after adjusting for co-morbidities.

CONCLUSIONS

CRT was associated with stabilization of renal function in patients with severe LV dysfunction and improvement in stage 4 and 5 CKD. Improved renal function was associated with a lower mortality.

Cardiac resynchronization therapy: results, challenges and perspectives for the future

Heart failure (HF) is considered as an epidemic and affects 2% of the population in the Western world. About 15-30% of patients with HF and reduced ejection fraction (HFrEF) also have prolonged QRS duration on the surface ECG, most commonly as a result of left-bundle branch block (LBBB). Increased QRS duration is a marker of a dyssynchronous activation, and subsequent contraction, pattern in the left ventricle (LV). When dyssynchrony is superimposed on the failing heart it further reduced systolic function and ultimately worsens outcome. During the past 15 years several randomized controlled clinical trials have documented that resynchronization of the dyssynchronous failing heart with a biventricular pacemaker - cardiac resynchronization therapy (CRT) - which can restore a more synchronous activation and contraction pattern. This translates in halted or reversed disease progression and improved clinical outcome, including reduced mortality. In this review, we will discuss several aspects of CRT including mechanisms of dyssynchrony and resynchronization in the failing heart, evidence of CRT efficacy derived from clinical trials and current challenges in CRT including patient selection and optimization of therapy delivery. Last, we will discuss future perspectives including the role of CRT to prevent adverse events in patients with an indication for antibradycardia pacing, the role of leadless pacing in the CRT setting as well as a new clinical arena where dyssynchrony and resynchronization may be important.

Comparative Effectiveness of CRT-D Versus Defibrillator Alone in HF Patients With Moderate-to-Severe Chronic Kidney Disease

BACKGROUND

Patients with moderate-to-severe chronic kidney disease (CKD) are poorly represented in clinical trials of cardiac resynchronization therapy (CRT).

OBJECTIVES

This study sought to assess the real-world comparative effectiveness of CRT with defibrillator (CRT-D) versus implantable cardioverter-defibrillator (ICD) alone in CRT-eligible patients with moderate-to-severe CKD.

METHODS

We conducted an inverse probability-weighted analysis of 10,946 CRT-eligible patients (ejection fraction <35%, QRS >120 ms, New York Heart Association functional class III/IV) with stage 3 to 5 CKD in the National Cardiovascular Data Registry (NCDR) ICD Registry, comparing outcomes between patients who received CRT-D (n = 9,525) versus ICD only (n = 1,421). Outcomes were obtained via Medicare claims and censored at 3 years. The primary endpoint of heart failure (HF) hospitalization or death and the secondary endpoint of death were assessed with Cox proportional hazards models. HF hospitalization, device explant, and progression to end-stage renal disease were assessed using Fine-Gray models.

RESULTS

After risk adjustment, CRT-D use was associated with a reduction in HF hospitalization or death (hazard ratio [HR]: 0.84; 95% confidence interval [CI]: 0.78 to 0.91; p < 0.0001), death (HR: 0.85; 95% CI: 0.77 to 0.93; p < 0.0004), and HF hospitalization alone (subdistribution HR: 0.84; 95% CI: 0.76 to 0.93; p < 0.009). Subgroup analyses suggested that CRT was associated with a reduced risk of HF hospitalization and death across CKD classes. The incidence of in-hospital, short-term, and mid-term device-related complications did not vary across CKD stages.

CONCLUSIONS

In a nationally representative population of HF and CRT-eligible patients, use of CRT-D was associated with a significantly lower risk of the composite endpoint of HF hospitalization or death among patients with moderate-to-severe CKD in the setting of acceptable complication rates.

Midkine Deteriorates Cardiac Remodeling via Epidermal Growth Factor Receptor Signaling in Chronic Kidney Disease

In chronic kidney disease, activation of the epidermal growth factor receptor (EGFR) leads to cardiac hypertrophy, which affects morbidity and mortality. In patients with renal insufficiency and heart failure, the expression of midkine, a heparin-binding growth factor, is increased. Therefore, we investigated the association between midkine and EGFR in the induction of cardiac hypertrophy and dysfunction in chronic kidney disease. We performed subtotal nephrectomies in midkine-knockout mice and wild-type mice. We found that subtotal nephrectomy-induced cardiac hypertrophy and phosphorylation of extracellular signal-regulated kinase 1/2 and AKT were attenuated in midkine-knockout mice compared with wild-type mice. An antiphosphotyrosine receptor antibody array was used to demonstrate that EGFR phosphorylation in the heart was also lower in midkine-knockout mice than in wild-type mice. Midkine induced EGFR, extracellular signal-regulated kinase 1/2, and AKT phosphorylation and led to hypertrophy in neonatal rat cardiomyocytes. Pretreatment with EGFR inhibitors or EGFR silencing suppressed midkine-stimulated phosphorylation of extracellular signal-regulated kinase 1/2 and AKT, induction of fetal cardiac gene expression, and hypertrophy in cardiomyocytes. To confirm the association between midkine and EGFR in vivo, mice subjected to subtotal nephrectomy were treated with the EGFR inhibitor gefitinib. Gefitinib treatment attenuated subtotal nephrectomy-induced cardiac hypertrophy. These results indicate that midkine might be a key mediator of cardiorenal interactions through EGFR activation, which plays a crucial role in cardiac hypertrophy in chronic kidney disease.

Left ventricular global longitudinal strain is associated with cardiovascular risk factors and arterial stiffness in chronic kidney disease

Background

Global longitudinal strain (GLS) has emerged as a superior method for detecting left ventricular (LV) systolic dysfunction compared to ejection fraction (EF) on the basis that it is less operator dependent and more reproducible. The 2-dimensional strain (2DS) method is easily measured and integrated into a standard echocardiogram. This study aimed to determine the relationship between GLS and traditional and chronic kidney disease (CKD)-related risk factors of cardiovascular disease (CVD) in patients with CKD.

Methods

A cross sectional study of patients with moderate CKD stages 3 and 4 (n = 136). Clinical characteristics, anthropometric, biochemical data including markers of inflammation [C-reactive protein (CRP)], uremic toxins [indoxyl sulphate (IS), p-cresyl sulphate (PCS)], and arterial stiffness [pulse wave velocity (PWV)] were measured. Inducible ischemia was detected using exercise stress echocardiogram. GLS was determined from 3 standard apical views using 2-dimensional speckle tracking and EF was measured using Simpson’s rule. Associations between GLS and traditional and CKD-related risk factors were explored using multivariate models.

Results

The study population parameters included: age 59.4 ± 9.8 years, 58 % male, estimated glomerular filtration rate (eGFR) 44.4 ± 10.1 ml/min/1.73 m², GLS −18.3 ± 3.6 % and EF 65.8 % ± 7.8 %. This study demonstrated that GLS correlated with diabetes (r = 0.21, p = 0.01), history of heart failure (r = 0.20, p = 0.01), free IS (r = 0.24, p = 0.005) free PCS (r = 0.23, p = 0.007), body mass index (BMI) (r = 0.28, p < 0.001), and PWV (r = 0.24, p = 0.009). Following adjustment for demographic, baseline co-morbidities and laboratory parameters,GLS was independently associated with free IS, BMI and arterial stiffness (R² for model = 0.30, p < 0.0001).

Conclusions

In the CKD cohort, LV systolic function assessed using GLS was associated with uremic toxins, obesity and arterial stiffness.

Electronic supplementary material

The online version of this article (doi:10.1186/s12882-015-0098-1) contains supplementary material, which is available to authorized users.

Long-Term Outcomes With Cardiac Resynchronization Therapy in Patients With Mild Heart Failure With Moderate Renal Dysfunction

Background—

We aimed to determine the impact of renal function on long-term outcomes with cardiac resynchronization therapy with defibrillator among patients with mild heart failure (HF).

Methods and Results—

We stratified 1820 Multicenter Automatic Defibrillator Implantation Trial–Cardiac Resynchronization Therapy patients by QRS morphology into those with and without left bundle-branch block. Subgroups within each QRS morphology category were created based on glomerular filtration rate (GFR): GFR <60 and ≥60 mL/min per 1.73 m 2 . Primary end point was death; secondary end points were HF/death and HF events alone during long-term follow-up. Among 1274 left bundle-branch block patients, 413 (32%) presented with GFR <60 (mean, 48.1±8.3) mL/min per 1.73 m 2 . Relative to the 861 (68%) patients with GFR ≥60 (mean, 79.6±16.0) mL/min per 1.73 m 2 , low-GFR patients experienced higher risk of death (hazard ratio [HR], 2.09; 95% confidence interval [CI], 1.53–2.86; P <0.01) and HF/death (HR, 1.46; 95% CI, 1.17–1.82; P <0.01). In both GFR groups, cardiac resynchronization therapy with defibrillator was associated with reduction in death (GFR <60: HR, 0.66; 95% CI, 0.44–1.00; P =0.05 and GFR ≥60: HR, 0.68; 95% CI, 0.44–1.05; P =0.08) and HF/death (GFR <60: HR, 0.49; 95% CI, 0.36–0.67; P <0.01 and GFR ≥60: HR, 0.50; 95% CI, 0.38–0.66; P <0.01). In the low-GFR group, there was greater absolute reduction in risk of death (GFR <60: 14% and GFR ≥60: 6%) and HF/death (GFR <60: 25 and GFR ≥60: 15%). Among non–left bundle-branch block patients, low GFR predicted outcomes; however, no benefit from cardiac resynchronization therapy with defibrillator was observed.

Conclusions—

In patients with mild HF, moderate renal dysfunction is associated with higher risk of death and HF during long-term follow-up. Patients with left bundle-branch block, regardless of baseline renal function, derive long-term benefit from cardiac resynchronization therapy with defibrillator, with greater absolute risk reduction in death and HF among those with moderate renal dysfunction.

Clinical Trial Registration—

URL: http://www.clinicaltrials.gov . Unique identifiers: NCT00180271, NCT01294449, and NCT02060110.

Association of serum levels of FGF23 and α-Klotho with glomerular filtration rate and proteinuria among cardiac patients

Background

Expression and/or excretion of fibroblast growth factor-23 (FGF23) and its co-receptor Klotho are altered in patients with end-stage renal disease. The possibility that the FGF23/α-Klotho system mediates the aggravated cardiovascular outcome among patients with chronic kidney disease (CKD) has been suggested. We determined whether FGF23 and α-Klotho concentrations are altered among patients with reduced renal function and proteinuria.

Methods

Serum FGF23 and α-Klotho were measured in cardiology patients who were not undergoing chronic hemodialysis. Estimated glomerular filtration rate (eGFR) was correlated negatively with FGF23 and positively with α-Klotho.

Results

The correlation between FGF23 and the renal tubular maximum reabsorption rate of phosphate to the GFR (TmP/GFR) was not significant, but that between FGF23 and serum calcium or inorganic phosphate was significant among patients with an estimated GFR of less than 60 mL/min/m². By stepwise multivariate regression analysis, eGFR was selected as significant predictor for FGF23 or α-Klotho among patients with an estimated GFR of less than 60 mL/min/m²; however, urine albumin/creatinine ratio was not selected as a predictor for FGF23 or α-Klotho irrespective of the eGFR levels. In patients with eGFR of <60 mL/min/1.73 m², UACR was significantly associated with log(FGF23); but, this association did not remain statistically significant in a multivariate model.

Conclusions

Among cardiology patients with various stages of CKD, serum concentrations of FGF23 and α-Klotho were associated with renal function, but not with the extent of proteinuria.

The association between glomerular filtration rate and left ventricular function in two independent community-based cohorts of elderly

Background

The cardiorenal syndrome, the detrimental bi-directional interplay between symptomatic heart failure and chronic kidney disease, is a major clinical challenge. Nonetheless, it is unknown if this interplay begins already at an asymptomatic stage. Therefore we investigated whether the glomerular filtration rate (GFR) is associated with left ventricular function in participants free from clinical heart failure and with a left ventricular ejection fraction (LVEF) >40% and with pre-specified sub-group analyses in individuals with a GFR >60 mL/min/m².

Methods

Two independent community-based cohorts were used; the Prospective Investigation of the Vasculature in Uppsala Seniors (PIVUS; n = 911; 50% women; mean age: 70 years) and the Uppsala Longitudinal Study of Adult Men (ULSAM; n = 538; mean age: 71 years). We investigated cross-sectional association between cystatin C-based GFR (estimated glomerular function [eGFR]) and systolic (LVEF), diastolic- (isovolumic relaxation time [IVRT]) and global left ventricular function (myocardial performance index [MPI]) determined by echocardiography.

Results

In both PIVUS and ULSAM, higher eGFR was significantly associated with higher LVEF (P = 0.004 [PIVUS] and P = 0.005 [ULSAM]). In PIVUS, higher eGFR was significantly associated with lower IVRT (P = 0.001) and MPI (P = 0.006), in age- and sex-adjusted models. After further adjustment for cardiovascular risk factors, the association between higher eGFR and higher LVEF was still statistically significant (P = 0.008 [PIVUS] and P = 0.02 [ULSAM]). In PIVUS, the age- and sex-adjusted association between eGFR and left ventricular function was similar in participants with eGFR >60 mL/min/m².

Conclusions

Our data suggest that the interplay between kidney and heart function begins prior to the development of symptomatic heart failure and kidney disease.

Impact of mild to moderate reductions of glomerular filtration rate on coronary artery disease severity

BACKGROUND & AIMS

The bases of the link between reduced glomerular filtration rate (GFR) and coronary artery disease (CAD) are complex and to some extent still unclear. We performed this observational, single referral center, cohort study to evaluate whether mild to moderate GFR reduction is associated with more severe CAD and/or with a worse cardiac prognosis independently of proteinuria, diabetes and traditional risk factors.

METHODS AND RESULTS

In 1752 consecutive non-diabetic patients without proteinuria or moderate/severe kidney disease undergoing a clinically driven coronary angiography, coronary arteries lesions, myocardial function and hypertrophy and 10-yrs incidence of cardiac events and death were evaluated in relation to classes of estimated GFR defined according the lowest eGFR value (105+, 90+, 75+, 60+, 45+). A reduced eGFR was independently associated with hypertension, myocardial hypertrophy and stress induced ischemia, while the excess coronary lesions and the worse myocardial systolic function were both largely explained by age and cardiovascular risk factors. When compared to subjects 75+, both the risk of cardiac death (1.67[1.10-2.57] and 3.06[1.85-5.10]) and non-fatal myocardial infarction (2.58[1.12-6.49] and 2.73[1.31-6.41]) adjusted for age and comorbidities were higher in eGFR 60+ and 45+ patients.

CONCLUSIONS

A mild-moderate reduction of eGFR is closely associated to higher rates of stress-induced ischemia, myocardial hypertrophy and higher risk of fatal and non-fatal cardiac events. The associations of reduced eGFR with coronary atherosclerosis and myocardial systolic dysfunction are both largely explained by age and traditional risk factors.

Contrast-induced acute kidney injury in patients undergoing cardiac resynchronization therapy-incidence and prognostic importance. Sub-analysis of data from randomized TRUST CRT trial

Introduction

Because data on contrast-induced acute kidney injury (CI-AKI) in patients undergoing cardiac resynchronization therapy (CRT-D) are scarce, we aimed to assess the incidence, natural course and prognostic importance of this syndrome in CRT recipients.

Methods

Study population consisted of 100 consecutive patients enrolled into the Triple Site Versus Standard Cardiac Resynchronization (TRUST CRT) trial, who were treated with CRT-D. Two patients were excluded up to 3 months after randomization and not analysed further. CI-AKI was defined as a rise in serum creatinine of at least 26.5 μmol/L (0.3 mg/dL) within 48 h after contrast exposure, or at least 50 % increase from the baseline value during index hospital stay with CRT-D implantation according to KDIGO Clinical Practice Guideline for Acute Kidney Injury.

Results

Among 98 subjects of TRUST CRT trial, 10 patients (10.2 %) developed CI-AKI after CRT-D implantation. In patients with glomerular filtration rate (GFR) <60 mL/min/1.73 m² on admission, the incidence of CI-AKI was almost twofold (15.4 %) higher than in subjects with GFR ≥60 (8.3 %). CRT-D recipients with CI-AKI had significantly higher mortality rate (50.0 %) compared to those without CI-AKI (17.0 %) during 30 months of follow-up (logrank p = 0.012). Multivariate Cox regression analysis showed CI-AKI as significant and independent risk factor for death in CRT-D recipients (hazard ratio 5.71; 95 % CI 5.16–6.26; p = 0.001).

Conclusions

Contrast-induced acute kidney injury is a serious and frequent procedural complication of CRT-D implantation with a significant negative influence on long-term survival. The results suggest that clinical evaluation regarding renal function should be considered in CRT-D recipients, both before and after device implantation.

Heart failure highlights in 2012-2013

Heart failure has become the cardiovascular epidemic of the century. The European Journal of Heart Failure is dedicated to the advancement of knowledge in the field of heart failure management. In 2012 and 2013, several pioneering scientific discoveries and paradigm-shifting clinical trials have been published. In the current paper, we will discuss the most significant novel insights into the pathophysiology, diagnosis, and treatment of heart failure that were published during this period. All relevant research areas are discussed, including pathophysiology, co-morbidities, arrhythmias, biomarkers, clinical trials, and device therapy, including left ventricular assist devices.

Usefulness and consequences of cardiac resynchronization therapy in dialysis-dependent patients with heart failure

Cardiac resynchronization therapy (CRT) is often deferred in dialysis-dependent patients with heart failure (HF) because of a perceived lack of benefit and potentially higher risks, although the outcomes associated with CRT in dialysis have not been reported. We therefore studied our center's experience with CRT in dialysis-dependent patients. We constructed a descriptive assessment of these patients (n = 15) and performed a case-control analysis matching for age, gender, bundle branch morphology, diabetes mellitus, cardiomyopathy origin, and β-blocker and angiotensin-converting enzyme inhibitor or angiotensin II receptor blocker use. Baseline and 6-month echocardiograms were assessed for evidence of reverse remodeling. No periprocedural or long-term complications were observed among dialysis patients. Heterogenous improvement in ejection fraction (+3.1 ± 9.2%) was noted and 2 patients derived absolute improvements of 8% and 22%, respectively. Dialysis patients demonstrated the following 3-year event rates: HF hospitalization, 31%; all-cause hospitalization, 100%; mortality, 73%; and HF hospitalization or death, 82%. In the case-control analysis, controls demonstrated superior reverse remodeling (+9.2 ± 9.5% increase in ejection fraction), decreased mortality (73% vs 44%, p = 0.038), and all-cause hospitalizations (76% vs 100%, p = 0.047), with no difference in HF hospitalizations (p = 0.39), compared with dialysis patients. In conclusion, at our center, the dialysis-dependent patients with HF who underwent CRT implantation did so safely and no serious complications were observed. Certain dialysis patients demonstrated compelling improvement after device implantation. Compared with matched controls, dialysis patients were at increased risk for adverse events and worsened echocardiographic outcomes.

Serum cystatin C concentration as an independent marker for hypertensive left ventricular hypertrophy

Background

Serum cystatin C levels can be used to predict morbidity and mortality in patients with cardiovascular disease. However, the clinical relevance of serum cystatin C levels in patients with hypertensive left ventricular hypertrophy (LVH) has rarely been investigated. We designed the present study to investigate whether serum cystatin C levels are associated with cardiac structural and functional alterations in hypertensive patients.

Methods

We enrolled 823 hypertensive patients and classified them into two groups: those with LVH (n = 287) and those without LVH (n = 536). All patients underwent echocardiography and serum cystatin C testing. We analyzed the relationship between serum cystatin C levels and LVH.

Results

Serum cystatin C levels were higher in hypertensive patients with LVH than in those without LVH (P < 0.05). Using linear correlation analysis, we found a positive correlation between serum cystatin C levels and interventricular septal thickness (r = 0.247, P < 0.01), posterior wall thickness (r = 0.216, P < 0.01), and left ventricular weight index (r = 0.347, P < 0.01). When analyzed by multiple linear regression, the positive correlations remained between serum cystatin C and interventricular septal thickness (β = 0.167, P < 0.05), posterior wall thickness (β = 0.187, P < 0.05), and left ventricular weight index (β = 0.245, P < 0.01).

Conclusion

Serum cystatin C concentration is an independent marker for hypertensive LVH.