Main pulmonary artery diameter in combination with cardiovascular biomarkers. New possibilities to identify pulmonary hypertension in patients with severe aortic valve stenosis?

BACKGROUND: Echocardiography is currently the noninvasive method of choice to screen patients with severe aortic valve stenosis (AS) for pulmonary hypertension (PH) by estimating systolic pulmonary artery pressure (sPAP). However, radiological options are also available by determining the main pulmonary artery (MPA) diameter in the setting of CT angiography. The aim of the present study was to compare cardiovascular biomarkers with the MPA diameter to allow other ways of detecting PH in patients with severe AS. METHODS: 194 patients with severe AS undergoing transcatheter aortic valve replacement (TAVR) were included in this study and were divided into two groups based on the CT-angiographically determined MPA diameter. In accordance with ESC guidelines, a cut-off value of 29 mm was determined in this study, with the absence of PH defined by an MPA diameter < 29 mm (n = 79/194) and the presence of PH defined by an MPA diameter ≥ 29 mm (115/194). Immediately before interventional aortic valve replacement, blood samples were drawn from the subjects and relevant cardiovascular biomarkers such as BNP, cTnI, GDF-15, H-FABP, IGF-BP2 and suPAR were assessed. RESULTS: Patients with an MPA diameter ≥ 29 mm had significantly higher BNP (p = 0.004), cTnI (p = 0.039) and HFABP (p = 0.015) plasma levels, whereas GDF-15 (p = 0.140), IGF-BP2 ( p = 0.088) and suPAR (p = 0.140) showed no significant differences. In addition, cut-off values were calculated to predict an MPA diameter ≥ 29 mm. Significant results were shown with 1634.00 pg/ml for BNP (p = 0.004), with 16.50 pg/ml for cTnI (p = 0.039) and with 1.16 ng/ml for H-FABP (p = 0.016). In a combined biomarker analysis, the 2-way combination of BNP and IGF-BP2 (AUC 0.671; 95%CI 0.538 - 0.805; p = 0.023) and the 3-way combination of BNP, H-FABP and IGF-BP2 (AUC 0.685; 95%CI 0.551 - 0.818; p = 0.015) showed the best results. Biomarker follow-up at 3 and 12 months after TAVR did not require additional information gain. Regarding 1-year survival, no significant difference could be detected between patients with an MPA diameter < 29 mm compared to patients with ≥ 29 mm (log-rank test: p = 0.262). CONCLUSIONS: The MPA diameter remains a controversial parameter for the detection of PH in patients with severe AS. Standing on its own, this non-invasive parameter may not be precise enough to detect PH accurately. Combining this parameter with several biomarkers did not provide significant additional information.

Transcatheter aortic valve implantation without prior balloon valvuloplasty is associated with less pronounced markers of myocardial injury.

BACKGROUND: Aortic valve stenosis is the most common valvulopathy in developed countries. Transcatheter aortic valve implantation (TAVI) is a therapeutic alternative in symptomatic patients at high or prohibitive perioperative risk. Predilatation by balloon aortic valvuloplasty (BAV) under rapid ventricular pacing (RVP) has been a routine part of TAVI. However, both RVP and BAV carry substantial risks and an increasing number of interventional centers are performing TAVI without predilatation (direct TAVI). A transient decrease of left ventricular function and elevated markers of myocardial injury after TAVI with predilatation were observed in previous studies. In this study, we investigated whether direct TAVI was associated with a similar increase in cardiac biomarkers and decrease in ejection fraction in a cohort of our patients. METHODS: Consecutive patients undergoing TAVI without predilatation using a self-expanding system at a single center between April 2013 and December 2015 were followed up for one year and were retrospectively analyzed regarding mortality, safety and efficacy endpoints as well as common laboratory and echocardiographic parameters. RESULTS: A total of 164 patients (83±6 years; 56% female) were included in the analysis. According to the Valve Academic Research Consortium 2 (VARC-2) criteria the technical success rate was 96.3% and 89.1% of patients remained free of a combined safety endpoint at 30 days. Mortality rates at 30 days and 1 year were 3.0% (N.=5) and 10.4% (N.=17), respectively. TAVI without predilatation was highly effective in lowering aortic valve peak velocity from 4.4±0.6 m/s before to 1.7±0.5 m/s (P<0.01), and mean pressure gradient across the valve from 48.7±15.1 mmHg to 8.3±4.5 mmHg (<0.05). Left ventricular function remained unaltered after the intervention (51±10% prior to TAVI and 51±9% post TAVI), whereas high sensitive troponin T (hs-TnT), a well-established marker for myocardial injury, increased significantly from 26 ng/L (interquartile range=18.00-44.00) to 119 ng/L (interquartile range=73.25-166.00, P<0.001) during this time. Notably, an increase in the plasma levels of hs-TnT >15 times the upper limit of normal was associated with mortality both one month and one year after TAVI. CONCLUSIONS: TAVI without predilatation is feasible, safe and effective for aortic valve replacement in symptomatic patients with severe aortic stenosis who are at high perioperative risk. In contrast to a cohort of patients who underwent TAVI with predilatation previously published by another center, our patients did not suffer from transient impairment of left ventricular function. As a marker of myocardial injury, hs-TnT showed a less pronounced increase than reported previously. This might be a marker for a prognostic benefit as hs-TnT has been shown to be a strong predictor of outcome in patients undergoing TAVI. We conclude that direct TAVI is a less invasive option involving less myocardial stress.

Atrial Fibrillation: A New Indicator for Advanced Colorectal Neoplasia in Screening Colonoscopy.

BACKGROUND: Colorectal cancer (CRC) is a common and potentially preventable malignancy. Evidence has emerged that coronary artery disease patients are at increased risk for developing CRC by shared risk factors. Here we investigated an association between CRC and atrial fibrillation (AF), a surrogate marker of cardiovascular risk, in the setting of routine screening colonoscopy. METHODS: We investigated 1949 asymptomatic participants (median age 61 [54-67] years, 49% females) undergoing screening colonoscopy within the SAKKOPI registry (Salzburg Colon Cancer Prevention Initiative). Forty-six participants with AF (2.4%) were identified, and colonoscopy findings were compared to non-AF participants. Propensity Score Matching (PSM) was used to create 1:1 and 3:1 age- and gender-matched couples. RESULTS: Abnormal findings on screening colonoscopy (any form of adenoma or carcinoma) were more common in AF participants with an odds ratios (OR) of 2.4 [1.3-4.3] in the unmatched analysis, and 2.6 [1.1-6.3] and 2.0 [1.1-4.0] in the 1:1 and 3:1 matched groups, respectively. Correspondingly, the odds of finding advanced adenomas or carcinomas was elevated about three-fold across the different matched and unmatched analyses (OR 3.3 [1.1-10.8] for 3:1 matched participants). At the same time, the prevalence and number of colonic lesions were significantly higher in AF participants (63.0% vs. 33.4% for 3:1 matched participants, p < 0.001). Non-CRC related findings on colonoscopy, like diverticulosis, were non-different between groups. CONCLUSION: Participants with AF had a higher burden of advanced premalignant adenomas and CRC in routine colonoscopy screening. Our data suggest that practitioners should monitor the CRC screening status, especially in AF patients.

Transcatheter aortic valve replacement for pure aortic valve regurgitation: "on-label" versus "off-label" use of TAVR devices.

INTRODUCTION: Transcatheter aortic valve replacement (TAVR) has become the mainstay of treatment for aortic stenosis in patients with high surgical risk. Pure aortic regurgitation (PAR) is considered a relative contraindication for TAVR; however, TAVR is increasingly performed in PAR patients with unfavorable risk profile. Herein, we aim to summarize available data on TAVR for PAR with special emphasis on "on-label" versus "off-label" TAVR devices. METHODS AND RESULTS: Pubmed was searched for studies of patients undergoing TAVR for PAR. Primary outcome was 30 day-mortality. Pooled estimated event rates were calculated. Twelve studies including a total of 640 patients were identified until December 2017. Among these, 208 (33%) patients were treated with devices with CE-mark approval for PAR ("on-label"; JenaValve and J valve). Overall, the procedural success rate was 89.9% (95% CI 81.1-96.1%; I2 80%). Major bleeding was reported in 6.4% (95% CI 2.9-10.8%; I2 48%). All-cause mortality at 30 days was 10.4% (95% CI 7.1-14.2%; I2 20%). Stroke occurred in 2.2% (95% CI 0.9-3.9%; I2 0%). A permanent pacemaker was required in 10.7% (95% CI 7.3-14.6%; I2 23%). At 30 days after TAVR, ≥ moderate AR post-interventional was observed in 11.5% (95% CI 2.9-23.6%; I2 90%). In the "on-label"-group, success rate was 93.0% (95% CI 85.9-98.1%; I2 52%). 30-day-mortality was 9.1% (95% CI 3.7-16.0%; I2 36%). More than trace AR was present in 2.8% (95% CI 0.1-7.6%; I2 0%). Compared to first-generation devices, second-generation devices were associated with significantly lower 30-day-mortality (r = - 0.10; p = 0.02), and significantly higher procedural success rates (r = 0.28; p < 0.001). Compared to other second-generation devices, the use of J valve or JenaValve was not associated with altered mortality (r = 0.04; p = 0.50), rates of > trace residual AR (r = - 0.05; p = 0.65) but with a significantly higher procedural success (r = 0.15; p = 0.042). CONCLUSION: Based on this summary of available observational data TAVR for PAR is feasible and safe in patients deemed inoperable. First-generation TAVR devices are associated with inferior outcome and should be avoided. The "on-label" use of PAR-certified TAVR devices is associated with a significantly higher procedural success rate and might be favorable compared to other second-generation devices.

Carcinoid heart disease involving the left heart: a case report and biomarker analysis.

Herein, we report the case of a 67-year-old woman who was admitted to our hospital because of dyspnoea and oedema of the lower extremities. Transthoracic echocardiography revealed severe tricuspid and mitral regurgitation, and the leaflets of the tricuspid valve were found to be rigid and almost immobile. The plasma concentrations of serotonin and chromogranin A were elevated, and hence, suspicion for carcinoid heart disease was raised. In addition to the diagnostic workup and medical and surgical treatment, we analysed levels of novel cardiovascular biomarkers throughout the entire follow-up by means of enzyme-linked immunosorbent assay. A dopa positron emission tomography (DOPA-PET) was conducted and showed a neoplasm in the terminal ileum. Tricuspid valve replacement, mitral valve repair, and a closure of the patent foramen ovale (PFO) were conducted. Two months later, hemicolectomy and liver segment resection were performed. The tumour was resected, and the diagnosis of a neuroendocrine tumour (NET) was confirmed. Throughout the follow-up, we observed a decrease in the plasma levels of novel biomarkers [e.g. interleukin-8 (IL-8), soluble suppression of tumorigenicity-2 (sST2), and heart-type fatty acid-binding protein (H-FABP)] over the follow-up period. In our case, carcinoid heart disease resulted in a severe tricuspid regurgitation as commonly seen in these patients. Moreover, a pre-existent mitral regurgitation was likely aggravated by fibrotic remodelling, because a PFO has led to a right-to-left shunt and might have caused left heart involvement. As IL-8 was associated with adverse outcomes in patients with NETs, and sST2 and H-FABP were associated with adverse outcomes in patients with heart failure previously, these biomarkers could aid in the risk stratification of patients with NET.

Visualization and appearance of artifacts of leadless pacemaker systems in cardiac MRI : An experimental ex vivo study.

BACKGROUND: Leadless pacemaker systems are an important upcoming device in clinical rhythmology. Currently two different products are available with the Micra system (Medtronic) being the most used in the clinical setting to date. The possibility to perform magnetic resonance imaging (MRI) is an important feature of modern pacemaker devices. Even though the Micra system is suitable for MRI, little is yet known about its impact on artifacts within the images. OBJECTIVE: The aim of our ex vivo study was to perform cardiac MRI to quantify the artifacts and to evaluate if artifacts limit or inhibit the assessment of the surrounding myocardium. METHODS: After ex vivo implantation of the leadless pacemaker (LP) in a porcine model, hearts were filled with saline solution and fixed on wooden sticks on a plastic container. The model was examined at 1.5 T and at 3 T using conventional sequences and T2 mapping sequences. In addition, conventional X­rays and computed tomography (CT) scans were performed. RESULTS: Correct implantation of the LP could be performed in all hearts. In almost all MRI sequences the right ventricle and the septal region surrounding the (LP) were altered by an artifact and therefore would sustain limited assessment; however, the rest of the myocardium remained free of artifacts and evaluable for common radiologic diagnoses. A characteristic shamrock-shaped artifact was generated which appeared to be even more intense in magnitude and brightness when using 3 T compared to 1.5 T. CONCLUSION: The use of the Micra system in cardiac MRI appeared to be feasible. In our opinion, it will still be possible to make important clinical cardiac MRI diagnoses (the detection of major ischemic areas or inflammatory processes) in patients using the Micra system. We suggest the use of 1.5 T as the preferred method in clinical practice.

Soluble ST2 predicts 1-year outcome in patients undergoing transcatheter aortic valve implantation.

BACKGROUND: Soluble ST2 (sST2) has been introduced as a novel biomarker in patients suffering from heart failure for risk stratification. In this study, we sought to investigate whether sST2 is useful for risk stratification and prediction of mortality in patients undergoing transcatheter aortic valve implantation (TAVI). MATERIALS AND METHODS: A total of 274 patients undergoing TAVI were included in this study (149 female; age 81 ± 1 years; EUROSCORE 25 ± 1; STS score 3·8 ± 0·2). Plasma samples were obtained preinterventional and analysed for sST2. Patients were followed up 1 month and 1 year after TAVI. RESULTS: In a Cox regression analysis, sST2 plasma concentration was associated with increased mortality (changes per pg/mL sST2 concentration; HR 1·00006 95% (1·00004-1·00009); P < 0·001). A cut-off by means of the Youden Index was calculated (10 070·27 pg/mL), and patients were retrospectively divided into two cohorts, in those above (31·3%) and those below (68·7%) this value. These two groups were then compared regarding mortality both after 30 days and 1 year: whereas 1-month mortality did not differ (7·0% vs. 10·3%, OR 1·50 95% CI (0·60-3·79; P = 0·46)), patients with a sST2 concentration above the cut-off of 10 070·27 pg/mL showed a significantly worse outcome after 1 year (49·2% vs. 23·2%; OR 3·21 95% CI (1·70-6·04); P < 0·001). After correction for confounders in a multivariate Cox regression analysis, sST2 (1·0002 95% CI (1·0001-1·0003); P = 0·001) concentration remained associated with mortality. CONCLUSIONS: sST2 levels were associated with 1-year mortality after TAVI. Based on these results, we assume that sST2 might help to identify patients at high risk for death in whom conservative treatment should be considered.

Analysis of Ambient Influences Affecting Interleukin-6 Secretion in the Context of Clinical Trials of Stem Cell Therapy for Myocardial Infarction.

BACKGROUND: Contradictory results of large clinical trials of stem cell therapy in acute myocardial infarction (AMI) have impeded a wider clinical use. As signalling via paracrine factors in AMI has received more and more attention recently, we sought to compare processing protocols with special emphasis on interleukin-6 (IL-6), a factor of major relevance for triggering cardioprotective signals via STAT3 and PI3K. METHODS: Bone marrow and peripheral blood mononuclear cells were processed according to protocols used in the REPAIR-AMI and ASTAMI study. RESULTS: Keeping cells at higher temperatures significantly boosted secretion of IL-6. Moreover, the use of autologous serum and X-Vivo medium was superior over reagents used in the protocol of the ASTAMI study. CONCLUSIONS: External influencing factors (higher temperature, use of a modern cell culture medium supplemented with serum) led to higher concentrations of IL-6. These results could provide an explanation for the superior results found in the REPAIR-AMI study.

Global research trends in the medical therapy of pulmonary arterial hypertension 2000-2014.

BACKGROUND: Pulmonary arterial hypertension is a progressive disease of the pulmonary vasculature that affects more than 200.000 patients worldwide. Without medical treatment it leads to right heart failure and death. Extensive fundamental and clinical research has been performed throughout the globe to modify the disease and improve survival. METHODS: We performed a bibliometric study on medical treatment for pulmonary arterial hypertension to identify study characteristics, impact factors and the countries of origin of basic and clinical studies that were published between 2000 and 2014. For visualization of the obtained data density equalizing maps were prepared. RESULTS: A total of 681 studies were eligible, of these 56% were clinical studies that have included a total of 30960 patients. Most studies were performed on endothelin receptor antagonists, followed by prostacyclins and phosphodiesterase type 5 inhibitors. Impact factors did not differ between clinical and basic science studies. The United States for clinical studies, and China for basic science studies were identified as main contributors to the global scientific output. CONCLUSIONS: This first bibliometric study in the field of pulmonary arterial hypertension shows that a significant amount of scientific research was performed within the last 14 years mainly in North America, Asia and Europe. As current trends in this field of research we identified combination therapies and Asian countries being a new hatchery for emerging experimental and clinical studies.

Estrogen attenuates left ventricular and cardiomyocyte hypertrophy by an estrogen receptor-dependent pathway that increases calcineurin degradation.

Left ventricular (LV) hypertrophy commonly develops in response to chronic hypertension and is a significant risk factor for heart failure and death. The serine-threonine phosphatase calcineurin (Cn)A plays a critical role in the development of pathological hypertrophy. Previous experimental studies in murine models show that estrogen limits pressure overload-induced hypertrophy; our purpose was to explore further the mechanisms underlying this estrogen effect. Wild-type, ovariectomized female mice were treated with placebo or 17beta-estradiol (E2), followed by transverse aortic constriction (TAC), to induce pressure overload. At 2 weeks, mice underwent physiological evaluation, immediate tissue harvest, or dispersion of cardiomyocytes. E2 replacement limited TAC-induced LV and cardiomyocyte hypertrophy while attenuating deterioration in LV systolic function and contractility. These E2 effects were associated with reduced abundance of CnA. The primary downstream targets of CnA are the nuclear factor of activated T-cell (NFAT) family of transcription factors. In transgenic mice expressing a NFAT-activated promoter/luciferase reporter gene, E2 limited TAC-induced activation of NFAT. Moreover, the inhibitory effects of E2 on LV hypertrophy were absent in CnA knockout mice, supporting the notion that CnA is an important target of E2-mediated inhibition. In cultured rat cardiac myocytes, E2 inhibited agonist-induced hypertrophy while also decreasing CnA abundance and NFAT activation. Agonist stimulation also reduced CnA ubiquitination and degradation that was prevented by E2; all in vitro effects of estrogen were reversed by an estrogen receptor (ER) antagonist. These data support that E2 reduces pressure overload induced hypertrophy by an ER-dependent mechanism that increases CnA degradation, unveiling a novel mechanism by which E2 and ERs regulate pathological LV and cardiomyocyte growth.

17 Beta-estradiol differentially affects left ventricular and cardiomyocyte hypertrophy following myocardial infarction and pressure overload.

BACKGROUND: We have shown previously that 17beta-estradiol (E2) increases left ventricular (LV) and cardiomyocyte hypertrophy after myocardial infarction (MI). However, E2 decreases hypertrophy in pressure overload models. We hypothesized that the effect of estrogen on cardiac hypertrophy was dependent on the type of hypertrophic stimulus. METHODS AND RESULTS: Ovariectomized wild-type female mice (n = 192) were given vehicle or E2 treatment followed by coronary ligation (MI), transverse aortic constriction (TAC), or sham operation. Signaling pathway activation was studied at 3, 24, and 48 hours, whereas echocardiography and hemodynamic studies were performed at 14 days. MI induced early but transient activation of p38 and p42/44 MAPK pathways, whereas TAC induced sustained activation of both pathways. E2 had no effect on these pathways, but increased Stat3 activation after MI while decreasing Stat3 activation after TAC. MI caused LV dilation and decreased fractional shortening (FS) that were unaltered by E2. TAC caused LV dilation, reduced FS, and increased LV mass, but in this model, E2 improved these parameters. After MI, E2 led to increases in myocyte cross-sectional area, atrial natriuretic peptide (ANP) and beta-myosin heavy chain (MHC) gene expression, but E2 diminished TAC-induced increases ANP and beta-MHC gene expression. CONCLUSIONS: These data demonstrate that the effects of E2 on LV and myocyte remodeling depend on the nature of the hypertrophic stimulus. The opposing influence of E2 on hypertrophy in these models may, in part, result from differential effects of E2 on Stat3 activation. Further work will be necessary to explore this and other potential mechanisms by which estrogen affects hypertrophy in these models.

Estrogen receptor alpha up-regulation and redistribution in human heart failure.

Clinical and animal studies suggest that estrogen receptors are involved in the development of myocardial hypertrophy and heart failure. In this study, we investigated whether human myocardial estrogen receptor alpha (ERalpha) expression, localization, and association with structural proteins was altered in end stage-failing hearts. We found a 1.8-fold increase in ERalpha mRNA and protein in end-stage human dilated cardiomyopathy (DCM, n=41), as compared with controls (n=25). ERalpha was visualized by confocal immunofluorescence microscopy and localized to the cytoplasm, sarcolemma, intercalated discs and nuclei of cardiomyocytes. Immunofluorescence studies demonstrated colocalization of ERalpha with beta-catenin at the intercalated disc in control hearts and immunoprecipitation studies confirmed complex formation of both proteins. Interestingly, the ERalpha/beta-catenin colocalization was lost at the intercalated disc in DCM hearts. Thus, the ERalpha/beta-catenin colocalization in the intercalated disc may be of functional relevance and a loss of this association may play a role in the progression of heart failure. The increase of total ERalpha expression may represent a compensatory process to contribute to the stability of cardiac intercalated discs.

Upregulation of myocardial estrogen receptors in human aortic stenosis.

BACKGROUND: Estrogen receptor (ER)-mediated effects have been associated with the modulation of myocardial hypertrophy in animal models and in humans, but ER expression in the human heart and its relation to hypertrophy-mediated gene expression have not yet been analyzed. We therefore investigated sex- and disease-dependent alterations of myocardial ER expression in human aortic stenosis together with the expression of hypertrophy-related genes. METHODS AND RESULTS: ER-alpha and -beta, calcineurin A-beta, and brain natriuretic peptide (BNP) mRNA were quantified by real-time polymerase chain reaction in left ventricular biopsies from patients with aortic valve stenosis (n=14) and control hearts with normal systolic function (n=17). ER protein was quantified by immunoblotting and visualized by immunofluorescence confocal microscopy. ER-alpha mRNA and protein were increased 2.6-fold (P=0.003) and 1.7-fold (P=0.026), respectively, in patients with aortic valve stenosis. Left ventricular ER-beta mRNA was increased 2.6-fold in patients with aortic valve stenosis (P<0.0001). ER-alpha and -beta were found in the cytoplasm and nuclei of human hearts. A strong inverse correlation exists between ER-beta and calcineurin A-beta mRNA in patients with aortic valve stenosis (r=-0.83, P=0.002) but not between ER-alpha or -beta and BNP mRNA. CONCLUSIONS: ER-alpha and -beta in the human heart are upregulated by myocardial pressure load.