Endothelial dysfunction is a marker of systemic response to the cardiac resynchronization therapy in heart failure

Patients with volume-loaded right ventricle - quantification of left ventricular hemodynamic response to intervention measured by noninvasive pressure-volume loops

Volume loading of the right ventricle (RV) in patients with atrial septal defect (ASD) and patients with repaired Tetralogy of Fallot (rToF) affects the pumping mechanics of the left ventricle (LV). Intervention of the lesion will relieve the RV volume load however quantifiable impact on exercise capacity, arrhytmias or death are limited. A possible explanation could be remaining effects on the function of the LV. The aim of this study was therefore to investigate if hemodynamics of the LV differs between patients with RV volume load due to ASD or rToF and healthy controls and if they change after intervention. Eighteen patients with ASD, 17 patients with rToF and 16 healthy controls underwent cardiac magnetic resonance imaging (CMR) and maximal exercise test with continuous gas analysis. Reexamination was performed 13 ± 2 months after closure of the ASD in 13 of the patients and 10 ± 4 months after pulmonary valve replacement (PVR) in 9 of the patients with rToF. Non-invasive PV-loops from CMR and brachial pressures were analyzed. Stroke work (SW) and potential energy (PE) increased after ASD closure but not in ToF patients after valve repair. Patients with ASD or rToF had higher contractility and arterial elastance than controls. No major effects were seen in LV energetics or in peak VO2 after ASD closure or PVR. Peak VO2 correlated positively with SW and PE in patients with ASD (r = 0.54, p < 0.05; r = 0.61, p < 0.01) and controls (r = 0.72, p < 0.01; r = 0.53, p < 0.05) to approximately the same degree as peak VO2 and end-diastolic volume (EDV) or end-systolic volume (ESV). In ToF patients there was no correlation between PV loop parameters and peak VO2 even if correlation was found between peak VO2 and EDV or ESV. In conclusion, the LV seems to adapt its pumping according to anatomic circumstances without losing efficiency, however there are indications of persistent vascular dysfunction, expressed as high arterial elastance, which might have impact on exercise performance and prognosis. Future studies might elucidate if the duration of RV volume load and decreased LV filling have any impact on the ability of the vascular function to normalize after ASD closure or PVR.

Endothelial Dysfunction Drives CRTd Outcome at 1-Year Follow-Up: A Novel Role as Biomarker for miR-130a-5p

Endothelial dysfunction (ED) causes worse prognoses in heart failure (HF) patients treated with cardiac resynchronization therapy (CRTd). ED triggers the downregulation of microRNA-130 (miR-130a-5p), which targets endothelin-1 (ET-1). Thus, we evaluated ED and the response to CRTd by assessing miR-130a-5p and ET-1 serum levels. We designed a prospective multi-center study with a 1-year follow-up to evaluate ED, ET-1, and miR-130a-5p in CRTd patients with ED (ED-CRTd) vs. patients without ED (NED-CRTd). Clinical outcomes were CRTd response, HF hospitalization, cardiac death, and all-cause death. At 1-year follow-up, NED-CRTd (n = 541) vs. ED-CRTd (n = 326) patients showed better clinical statuses, lower serum values of B type natriuretic peptide (BNP: 266.25 ± 10.8 vs. 297.43 ± 16.22 pg/mL; p < 0.05) and ET-1 (4.57 ± 0.17 vs. 5.41 ± 0.24 pmol/L; p < 0.05), and higher values of miR-130a-5p (0.51 ± 0.029 vs. 0.41 ± 0.034 A.U; p < 0.05). Compared with NED-CRTd patients, ED-CRTd patients were less likely to be CRTd responders (189 (58%) vs. 380 (70.2%); p < 0.05) and had higher rates of HF hospitalization (115 (35.3%) vs. 154 (28.5%); p < 0.05) and cardiac deaths (30 (9.2%) vs. 21 (3.9%); p < 0.05). Higher miR-130a-5p levels (HR 1.490, CI 95% [1.014−2.188]) significantly predicted CRTd response; the presence of hypertension (HR 0.818, CI 95% [0.669−0.999]), and displaying higher levels of ET-1 (HR 0.859, CI 98% [0.839−0.979]), lymphocytes (HR 0.820, CI 95% [0.758−0.987]), LVEF (HR 0.876, CI 95% [0.760−0.992]), and ED (HR 0.751, CI 95% [0.624−0.905]) predicted CRTd non-response. Higher serum miR-130a-5p levels (HR 0.332, CI 95% [0.347−0.804]) and use of ARNI (HR 0.319, CI 95% [0.310−0.572]) predicted lower risk of HF hospitalization, whereas hypertension (HR 1.818, CI 95% [1.720−2.907]), higher BNP levels (HR 1.210, CI 95% [1.000−1.401]), and presence of ED (HR 1.905, CI 95% [1.238−2.241]) predicted a higher risk of HF hospitalization. Hence, serum miR-130a-5p could identify different stages of ED and independently predict CRTd response, therefore representing a novel prognostic HF biomarker.

Does cardiac resynchronization therapy restore peripheral circulatory homeostasis?

Aims

To evaluate whether peripheral circulatory ‘remodelling’ as measured by changes in vascular compliance and in markers of nitric oxide signalling contributes to patient response to cardiac resynchronization therapy (CRT).

Methods and results

Effects of CRT were evaluated in 33 patients pre‐procedure and 6 months post‐procedure. Peak oxygen consumption, 6 min walk distance, New York Heart Association class, and quality of life score were evaluated. Augmentation index and its interactions with nitric oxide (NO) were evaluated by applanation tonometry. Platelet NO responsiveness and content of thioredoxin‐interacting protein were assessed. Plasma concentrations of N‐terminal proBNP, asymmetric and symmetric dimethylarginine (SDMA), high sensitivity C‐reactive protein, catecholamines, and matrix metalloproteinases‐2 and ‐9 were assessed. Despite significant improvement in 6 min walk distance (P = 0.005), New York Heart Association class (P < 0.001), quality of life (P = 0.001), and all echocardiographic parameters post‐CRT, there were no significant changes in augmentation index measurements, thioredoxin‐interacting protein content, and platelet NO response. Significant falls in N‐terminal proBNP (P = 0.008) and SDMA (P = 0.013; independent of renal function) occurred. Falls in SDMA predicted reduction in high‐sensitivity C‐reactive protein (P = 0.04) and increases in peak oxygen consumption (P = 0.04). There were no correlations between changes in echocardiographic parameters and those in vascular function.

Conclusions

These data suggest that the beneficial effects of CRT over 6 months are independent of any change in peripheral NO‐related signalling. However, there is evidence that suppression of inflammation occurs, and its magnitude predicts extent of clinical improvement.

Peripheral endothelial function may predict the effectiveness of beta-blocker therapy in patients with idiopathic dilated cardiomyopathy

OBJECTIVES

Beta-blockers have improved the prognosis of patients with dilated cardiomyopathy as they improve left ventricular (LV) systolic function and structure, which are crucial for myocardial recovery. However, to date, no accurate methods can predict the effectiveness of β-blocker therapy. Our goal was to evaluate whether peripheral endothelial function could be a useful predictor for β-blocker responses and related LV reverse remodeling (LVRR) in patients with idiopathic dilated cardiomyopathy (IDC).

METHODS

Fifty-two IDC patients were recruited and underwent brachial artery flow-mediated dilation (FMD). Beta-blockers were titrated to doses tolerable for each patient. LV function and structure were measured by echocardiography. A positive response to β-blockers was defined as an increase of ≥10% in LV ejection fraction (LVEF). LVRR was defined as an increase of ≥10% in LVEF and a decrease of ≥15% in LV end-systolic volume (LVESV).

RESULTS

Baseline FMD was 8.4±3.0% in IDC patients and significantly lower than healthy controls. At three-month follow-up, 54% of patients had a positive β-blocker response and 40% achieved LVRR. Patients with a positive response to β-blockers or with LVRR had significantly higher baseline FMD values than those without. FMD was the most significant predictor of changes in LVEF and LVESV. The sensitivity and specificity of baseline FMD to predict β-blocker responses was 64.3% and 83.3%, respectively, and to predict LVRR was 61.9% and 80.6%, respectively. Beta-blockers themselves did not influence FMD values.

CONCLUSIONS

FMD could serve as an independent predictor for monitoring β-blocker therapy effectiveness in IDC patients.