Tissue and Serum Biomarkers in Degenerative Aortic Stenosis-Insights into Pathogenesis, Prevention and Therapy.

BACKGROUND AND AIM: Degenerative Aortic Stenosis (DAS) is a common disease that causes substantial morbidity and mortality worldwide, especially in the older population. Our aim was to further investigate novel serum and tissue biomarkers to elucidate biological processes involved in this entity. MATERIAL AND METHODS: We evaluated the expression of six biomarkers significantly involved in cardiovascular pathology, i.e., irisin, periostin, osteoglycin, interleukin 18, high mobility group box 1 and proprotein convertase subtilisin/kexin type 9 in the serum at the protein level, and in the tissue at both the protein and mRNA levels of patients with AS (N = 60). Five normal valves obtained after transplantation from hearts of patients with idiopathic dilated cardiomyopathy were also studied. Serum measurements were also performed in 22 individuals without valvular disease who served as controls (C). RESULTS: Higher levels of all factors were found in DAS patients' serum than in normal C. IHC and PCR mRNA tissue analysis showed the presence of all biomarkers in the aortic valve cusps with DAS, but no trace of PCR mRNA was found in the five transplantation valves. Moreover, periostin serum levels correlated significantly with IHC and mRNA tissue levels in AS patients. CONCLUSION: We showed that six widely prevalent biomarkers affecting the atherosclerotic process were also involved in DAS, suggesting a strong osteogenic and pro-inflammatory profile, indicating that aortic valve calcification is a multifactorial biological process.

Dynamics and prognostic value of B-type natriuretic peptide in left ventricular assist device recipients.

BACKGROUND: The prognostic utility of B-type natriuretic peptide (BNP) in heart failure is well recognized. Previous studies demonstrated that BNP levels decrease after left ventricular assist device (LVAD) implantation. We sought to investigate the predictive value of baseline and changes in BNP levels in LVAD recipients. METHODS: BNP was measured in baseline and follow-up plasma samples from consecutive patients receiving a continuous-flow LVAD from 2010 through 2016. Absolute values and changes from baseline were related to clinical outcomes. RESULTS: Median BNP at baseline was 885 [interquartile range (IQR): 450-1,624] pg/mL, decreasing to 289 (IQR: 154-534) pg/mL at 90 days after LVAD implantation. Cox regression analysis revealed that higher baseline and follow-up BNP levels were not associated with increased risk of death at 180 days (P=0.12 and P=0.32, respectively). In the univariate analysis 90-day BNP, but not baseline BNP, was significantly associated with the combined death/hospitalization outcome 180 days after LVAD implantation [hazard ratio (HR) 1.03, 95% CI: 1.01-1.06; P=0.006]. This significance was not preserved after adjusting for multiple covariates (HR 1.01, 95% CI: 0.98-1.04; P=0.62). At 90 days, there was no BNP lowering in 20.6% of subjects. This was not associated with higher risk for death or the composite of death/hospitalization (P=0.11 and P=0.06 respectively). CONCLUSIONS: BNP absolute levels and changes from baseline are not independently associated with clinical outcomes after LVAD-implantation. These findings suggest an impaired prognostic performance of BNP after LVAD implantation.

Differential expression patterns of Toll Like Receptors and Interleukin-37 between calcific aortic and mitral valve cusps in humans.

BACKGROUND: Significant differences are mentioned in the progress of calcification between aortic and mitral valve. Evidence of inflammation in calcific aortic and mitral valve disease suggests that pathways of Toll Like Receptors (TLR) and Interleukin (IL)-37 expression may contribute to this process. We sought to investigate the role of TLR-mediated inflammatory response and IL-37 pathway expression on aortic and mitral valve calcification. MATERIAL AND METHODS: One-hundred twenty stenotic valve cusps/leaflets (60 aortic, 60 mitral) were excised during surgery and were collected for histological, immunohistochemistry and morphometric analysis at our department. After total RNA isolation from a second part of valve cusps/leaflets, cDNA synthesis and quantitative reverse transcription polymerase chain reaction (qRT-PCR) protocols were performed and relative mRNA levels of target genes were assessed. RESULTS: By histological analysis, the anti-inflammatory IL-37 levels were increased in mitral valve leaflets (MVL) compared to aortic valve cusps (AVCu) while all other biomarkers, including TLR, presented a reverse pattern with decreased levels as compared to AVCu. In terms of calcification biomarkers, only osteopontin differed between AVCu and MVL. mRNA analysis confirmed increased expression of IL-37 and decreased levels of TLR in MVL compared to AVCu. CONCLUSIONS: Stenotic cusps of aortic valves express lower IL-37 and increased TLRs levels than stenotic mitral valve leaflets, suggesting a differential pro-calcification and pro-inflammatory profile between the two valves. This may explain the higher incidence of calcification of AVCu than MVL and offer therapeutic considerations.

Resternotomy does not adversely affect outcome after left ventricular assist device implantation.

BACKGROUND: Resternotomy in cardiac surgery is considered a risk factor for postoperative complications. Previous studies have demonstrated an ambiguous relationship between resternotomy and clinical outcomes. Registry data from a mixed population of durable circulatory support devices suggest that history of cardiac surgery is a risk factor for mortality. Our study investigates the prognostic significance of resternotomy in a homogenous cohort of left ventricular assist device (LVAD) recipients. METHODS: The study included adult patients receiving a continuous-flow LVAD at our institution during the period 2010-2016. Postoperative adverse events and length of stay were analyzed. Survival was assessed at 6 months and by the end of the study. Multivariate risk factor analysis was conducted for independent predictors of death. RESULTS: One hundred twelve patients, who received an intrapericardial LVAD (HVAD, HeartWare), were included in our analysis. Twenty-four patients (21.4%) had a history of previous sternotomy. These patients were older and non-eligible for bridging, and had more frequently coronary heart disease. Univariate analysis demonstrated no differences in the observed complications postoperatively. Survival was similar among groups. Destination therapy was the only predictor of mortality in our analysis (p = 0.02). CONCLUSIONS: Resternotomy was not associated with worse outcomes after LVAD implantation in our cohort.

Serum and tissue biomarkers in aortic stenosis.

BACKGROUND: Calcific aortic valve stenosis (CAVS) is seen in a large proportion of individuals over 60 years. It is an active process, influenced by lipid accumulation, mechanical stress, inflammation, and abnormal extracellular matrix turnover. Various biomarkers (BMs) are studied, as regards mechanisms, diagnosis and prognosis. METHODS: In the calcified valves calcium deposition, elastin fragmentation and disorganization of cellular matrix were assessed, together with expression of OPN, OPG, osteocalcin (OCN) and RL2. We prospectively studied the following serum BMs in 60 patients with CAVS and compared them to 20 healthy controls, free from any cardiac disease: Matrix metalloproteinases (MMP) 2 and 9 and tissue inhibitor of metalloproteinase 1 (TIMP1), which regulate collagen turnover, inflammatory factors, i.e. tumor necrosis factor a (TNFa), interleukin 2 (IL2), transforming growth factor ß1 (TGF-ß1) which regulates fibrosis, fetuin-A (fet-A), osteopontin (OPN), osteoprotegerin (OPG), sclerostin (SOST), and relaxin-2 (RL2) which positively or negatively regulate calcification. Monocyte chemoattractant protein 1 (MCP-1) which regulates migration and infiltration of monocytes/macrophages was also studied as well as malondialdehyde (MDA) an oxidative marker. RESULTS: Extent of tissue valve calcification (Alizarin Red stain) was negatively correlated with tissue elastin, and RL2, and positively correlated with tissue OCN and serum TIMP1 and MCP-1 and negatively with MMP9. Tissue OCN was positively correlated with OPN and negatively with the elastin. Tissue OPN was negatively correlated with elastin and OPG. Tissue OPN OPG and RL2 were not correlated with serum levels In the serum we found in patients statistically lower TIMP1, fet-A and RL2 levels, while all other BMs were higher compared to the healthy group. Positive correlations between SOST and IL2, OPG and MDA but negative with TNFa and OPN were found; also MMP9 was negatively correlated with TNFa and MCP-1 was negatively correlated with TIMP1. CONCLUSION: We found that many BMs expressing calcification, collagen breakdown, or formation, and inflammation are increased in the valve tissue and in the serum of patients with CAVS as compared with healthy group. Our findings may give new insights towards diagnosis but also therapy. Thus antisclerostin, and antiflammatory agents could be tried for preventing aortic calcification progression.

Increased number of circulating progenitor cells after implantation of ventricular assist devices.

BACKGROUND: Bone marrow-derived circulating progenitor cells possess tissue repair potential, improving perfusion, left ventricular remodeling, and contractility in experimental models. We quantified and investigated the kinetics of 4 circulating progenitor cell sub-populations on the basis of CD34, CD133, and vascular endothelial growth factor receptor-2 (VEGFR-2) antigen expression. METHODS: CD34+, CD34+/CD133+/VEGFR-2-, CD34+/CD133+/VEGFR-2+, and CD34+/CD133-/VEGFR-2+ cells were counted in 10 male patients with end-stage congestive heart failure. Five underwent left ventricular/biventricular assist device (LVAD/BiVAD) implantation (VAD group), and 5 were ineligible for VAD implantation (no-VAD group). Peripheral blood was collected at 3 time points for each patient: before, 15, and 60 days after VAD placement in the VAD group and at the same time points in the no-VAD group. Purified CD34+ cells were stained with anti-CD34, anti-CD133, and anti-VEGFR-2 monoclonal antibodies and analyzed by flow cytometry. Serum levels of granulocyte-colony stimulating factor (G-CSF), interleukin-8, vascular endothelial growth factor-alpha (VEGF-alpha), and B-type natriuretic peptide (BNP) were also measured. RESULTS: In the VAD group the number of CD34+ cells/ml of blood tended to increase, from 159.6 +/- 137.0 at baseline to 428.9 +/- 224.3 at 15 days, and decreased to 343.8 +/- 165.7 at 60 days (p = 0.05 vs no-VAD group). In the other 3 cell populations, no significant differences occurred over time or between groups. A significant interaction between BNP levels and VAD status was observed (p = 0.005): BNP levels decreased over time in VAD patients vs no-VAD patients. G-CSF levels tended to decrease over time in both groups, but without a significant difference (p = 0.3). Serum levels of interleukin-8 and VEGF-alpha over time or between VAD and no-VAD patients were not significantly different. CONCLUSIONS: After VAD implantation, a transient increase occurs in the number of circulating CD34+ cells, in parallel to a reduction in BNP levels. Release of these cells from the bone marrow may contribute to the improvement of tissue perfusion and cardiac recovery occasionally seen after VAD placement.

Right atrial and septal reconstruction after tumor excision: the single-patch technique.

Surgical excision is the only therapy for benign atrial tumors, if serious complications are to be avoided. We propose a simplified technique whereupon a single autologous pericardial patch is used to not only close the septal defect, but to also reconstruct the right atrium. This new technique allows for wide excision of tumors without reduction of the right atrium, distortion of the tricuspid valve or traction on the atrioventricular node. We propose that this new approach will probably reduce the incidence of postoperative arrhythmias.

Orthotopic heart transplantation: ten years' clinical experience.

INTRODUCTION: Heart transplantation is the "gold standard" in the treatment of patients with end-stage heart failure who satisfy strict selection criteria. METHODS: We reviewed ten years' clinical experience (1996-2006) from 53 orthotopic transplants in our centre. RESULTS: Low perioperative (3.7%) and long-term (7.5%) mortality rates yielded a 95% survival rate in the first year, 92% at five years, and 70% at ten years--significantly better than the corresponding rates worldwide. In addition, excellent functional recovery was achieved in all transplant recipients. CONCLUSIONS: The strict application of international criteria in the selection of both candidates and donors, together with uninterrupted, multidisciplinary follow up, have made it feasible to perform heart transplantation with excellent results, despite the curiously low number of potential recipients and the shortage of acceptable donor hearts.

Calculated reduction aortoplasty for dilatation of the ascending aorta associated with aortic valve replacement.

BACKGROUND: Previous studies have advocated reduction aortoplasty to normalize the diameter of a moderately dilated ascending aorta associated with aortic valve disease. One of the reported techniques is the shawl lapel aortoplasty, which we have adopted and modified by setting a simple set of calculations. We present our midterm results. METHODS: Between February 1996 and February 2004, 25 patients underwent reduction aortoplasty during replacement of their aortic valves. Concomitant cardiac procedures were performed in 11 patients. Eighteen patients had predominantly severe aortic valve stenosis and 7 patients moderate to severe aortic valve insufficiency. Ascending aortic aneurysm size ranged from 43 to 50 mm, measured echocardiographically. In one small sized patient the aorta was 38 mm. Following their discharge patients were instructed to have control echocardiograms every 6 months for the first postoperative year and then annually. They were interviewed by telephone annually to date. RESULTS: There were no hospital deaths. Twenty-four patients were alive at follow-up, at 2 to 96 months (average 2.9 years). There was one late death, 2 years postoperatively. The first follow-up transthoracic echocardiogram performed at a mean of 6.2 months postoperatively (range, 1-11 months), as well as the subsequent annual echocardiograms in all patients, showed no evidence of further enlargement of the ascending aorta, compared to the reduced diameter obtained during the initial operation. The first 3 patients of this study remained essentially unchanged postoperatively, with only a minor reduction of their aortic diameter. CONCLUSIONS: The shawl lapel technique based on simple calculations, used as a diameter-reduction strategy for ascending aortic dilatation encountered during aortic valve replacement, is an efficacious method with excellent medium-term results.

Inhaled iloprost controls pulmonary hypertension after cardiopulmonary bypass.

PURPOSE: Severe pulmonary hypertension (PH) is a major cause of right ventricular (RV) dysfunction. Various iv vasodilator modalities have been used with limited results because of lack of pulmonary selectivity. The aim of the present controlled study was to evaluate the efficacy of inhaled iloprost, a synthetic prostacyclin analogue, in patients with elevated pulmonary vascular resistance (PVR) immediately after separation from cardiopulmonary bypass (CPB). METHODS: Twelve patients with persistent PH after discontinuation of CPB were included in the study. In all patients standard hemodynamic monitoring was used. Inhaled iloprost was administered via nebulized aerosol at a cumulative dose of 0.2 micro g*kg(-1) for a total duration of 20 min. Complete sets of hemodynamic measurements were performed before inhalation (baseline), during and after cessation of the inhalation period. Echocardiographic monitoring of RV function was also used. RESULTS: Inhaled iloprost induced a reduction in the transpulmonary gradient at the end of the inhalation period in comparison to baseline (9.33 +/- 3.83 mmHg vs 17.09 +/- 6.41 mmHg, P < 0.05). The mean pulmonary artery pressure to systemic artery pressure ratio decreased over this period (0.28 +/- 0.08 vs 0.45 +/- 0.17, P < 0.05). A statistically significant decrease of the PVR to systemic vascular resistance ratio was also observed (0.15 +/- 0.05 vs 0.21 +/- 0.05, P < 0.05). Improved indices of RV function were observed in echocardiographic monitoring. CONCLUSION: Inhaled iloprost appears to be a selective pulmonary vasodilator and may be effective in the initial treatment of PH and the improvement of RV performance in the perioperative setting.