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46 result(s) for "Caglayan, Evren"
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Pacing-induced cardiomyopathy in chronic right ventricular apical pacing: a midterm follow-up study
Background Data concerning the effect of chronic right ventricular pacing in patients with normal left ventricular ejection fraction (LVEF%) are contradictory. The aim of this study is to evaluate the prevalence of pacing-induced cardiomyopathy (PICM) at midterm follow-up after permanent pacemaker implantation (PPM). Methods A series of 170 patients were submitted to PPM within our facility. Inclusion criteria were the absence of structural heart disease and a preserved LVEF% (> 45%) at the time of PPM. A midterm clinical and echocardiographic follow-up was performed, and data were collected and analyzed retrospectively. PICM was defined as follow-up LVEF ≤ 45%, dyskinesia during RV pacing, and the absence of other known causes of cardiomyopathy. Results At a median echocardiographic follow-up of 24.5 months (IQR 10.0–43.0 months), the overall mean LVEF% decreased from a preimplantation value of 66.7% (± 8.6%) to 63.2% (± 10.6%) ( p  < 0.0001). PICM occurred in 11 patients (6.5%). Patients developing PICM had a significantly lower preimplantation LVEF% (58.4 ± 8.0% vs. 67.3 ± 8.4%; p  = 0.005), a trend for higher right ventricular pacing time rate (0.7 ± 0.3 vs. 0.5 ± 0.4; p  = 0.1), a significantly lower rate of PPM indication for sick sinus syndrome (SSS) (18.2% vs. 61.0%; p  = 0.009), and significantly higher rate of second-grade cardiac conduction block (36.4% vs. 11.3%; p  = 0.03). At multivariate logistic regression, only preimplantation LVEF% (OR = 0.88; CI 0.80–0.96; p  = 0.006) and the presence of SSS (OR = 0.1; CI 0.03–0.9; p  = 0.04) were independently related (inverse relationship) to follow-up PICM. Conclusions In this selected PPM patient cohort with preserved LVEF%, the rate of PICM at midterm follow-up is relatively low, but its occurrence seems to be related to baseline LVEF% and PPM indication category.
Heart rate at discharge in patients with acute decompensated heart failure is a predictor of mortality
Aims Heart failure is a syndrome with increasing prevalence in concordance with the aging population and better survival rates from myocardial infarction. Morbidity and mortality are high in chronic heart failure patients, particularly in those with hospital admission for acute decompensation. Several risk stratification tools and score systems have been established to predict mortality in chronic heart failure patients. However, identification of patients at risk with easy obtainable clinical factors that can predict mortality in acute decompensated heart failure (ADHF) are needed to optimize the care-path. Methods and results We retrospectively analyzed electronic medical records of 78 patients with HFrEF and HFmrEF who were hospitalized with ADHF in the Heart Center of the University Hospital Cologne in the year 2011 and discharged from the ward after successful treatment. 37.6 ± 16.4 months after index hospitalization 30 (38.5%) patients had died. This mortality rate correlated well with the calculated predicted survival with the Seattle Heart Failure Model (SHFM) for each individual patient. In our cohort, we identified elevated heart rate at discharge as an independent predictor for mortality ( p  = 0.016). The mean heart rate at discharge was lower in survived patients compared to patients who died (72.5 ± 11.9 vs. 79.1 ± 11.2 bpm. Heart rate of 77 bpm or higher was associated with an almost doubled mortality risk ( p  = 0.015). Heart rate elevation of 5 bpm was associated with an increase of mortality of 25% ( p  = 0.022). Conclusions Patients hospitalized for ADHF seem to have a better prognosis, when heart rate at discharge is < 77 bpm. Heart rate at discharge is an easily obtainable biomarker for risk prediction of mortality in HFrEF and HFmrEF patients treated for acute cardiac decompensation. Taking into account this parameter could be useful for guiding treatment strategies in these high-risk patients. Prospective data for validation of this biomarker and specific intervention are needed.
Pulmonary arterial remodelling by deficiency of peroxisome proliferator-activated receptor-γ in murine vascular smooth muscle cells occurs independently of obesity-related pulmonary hypertension
Background Obesity is associated with cardiovascular complications, including pulmonary hypertension (PH). Reports suggest that peroxisome proliferator-activated receptor-γ (PPARγ) has direct action in preventing vascular remodelling in PH. Here we dissected the specific role of high-fat-diet (HFD)-induced obesity and vascular smooth muscle cell (VSMC)-PPARγ for remodelling of small pulmonary arteries. Methods Wild-type (WT) and VSMC-specific PPARγ-knockout (Sm Pparγ −/− ) mice were fed a low-fat-diet (LFD, 10% kcal from fat) or HFD (60% kcal from fat) for 24 weeks. Mice were metabolically phenotyped (e.g. weight development, insulin/glucose tolerance) at the beginning, and after 12 and 24 weeks, respectively. At 24 weeks additionally pulmonary pressure, heart structure, pulmonary vascular muscularization together with gene and protein expression in heart and lung tissues were determined. Results HFD increased right ventricular systolic pressure (RVSP) to a similar extent in WT and Sm Pparγ −/− mice. HFD decreased glucose tolerance and insulin sensitivity in both WT and Sm Pparγ −/− mice. Importantly, the increase in RVSP correlated with the degree of insulin resistance. However, VSMC-PPARγ deficiency increased pulmonary vascular muscularization independently of the diet-induced rise in RVSP. This increase was associated with elevated expression of early growth response protein 1 in heart and osteopontin in lung tissue. Conclusions Here we demonstrate a correlation of insulin resistance and pulmonary pressure. Further, deficiency of PPARγ in VSMCs diet-independently leads to increased pulmonary vascular muscularization.
Hypoxia Enhances Platelet-derived Growth Factor Signaling in the Pulmonary Vasculature by Down-Regulation of Protein Tyrosine Phosphatases
Platelet-derived growth factor (PDGF) plays a pivotal role in the pathobiology of pulmonary hypertension (PH) because it promotes pulmonary vascular remodeling. PH is frequently associated with pulmonary hypoxia. To investigate whether hypoxia alters PDGF β receptor (βPDGFR) signaling in the pulmonary vasculature. The impact of chronic hypoxia on signal transduction by the βPDGFR was measured in human pulmonary arterial smooth muscle cells (hPASMC) in vitro, and in mice with hypoxia-induced PH in vivo. Chronic hypoxia significantly enhanced PDGF-BB-dependent proliferation and chemotaxis of hPASMC. Pharmacologic inhibition of PI3 kinase (PI3K) and PLCγ abrogated these events under both normoxia and hypoxia. Although hypoxia did not affect βPDGFR expression, it increased the ligand-induced tyrosine phosphorylation of the receptor, particularly at binding sites for PI3K (Y751) and PLCγ (Y1021). The activated βPDGFR is dephosphorylated by protein tyrosine phosphatases (PTPs). Interestingly, hypoxia decreased expression of numerous PTPs (T cell PTP, density-enhanced phosphatase-1, PTP1B, and SH2 domain-containing phosphatase-2), resulting in reduced PTP activity. Hypoxia-inducible factor (HIF)-1α is involved in this regulation of gene expression, because hypoxia-induced βPDGFR hyperphosphorylation and PTP down-regulation were abolished by HIF-1α siRNA and by the HIF-1α inhibitor 2-methoxyestradiol. βPDGFR hyperphosphorylation and PTP down-regulation were also present in vivo in mice with chronic hypoxia-induced PH. Hypoxia reduces expression and activity of βPDGFR-antagonizing PTPs in a HIF-1α-dependent manner, thereby enhancing receptor activation and proliferation and chemotaxis of hPASMC. Because hyperphosphorylation of the βPDGFR and down-regulation of PTPs occur in vivo, this mechanism likely has significant impact on the development and progression of PH and other hypoxia-associated diseases.
Detection of arrhythmia using an implantable cardiac monitor following a cryptogenic stroke: a single-center observational study
Background Detection of atrial fibrillation (AF) after cryptogenic stroke (CS) has therapeutic implications, but the most effective type and optimal duration of monitoring have still to be defined. This study that involved patients with CS or transient ischemic attack (TIA), all of whom carried an implantable cardiac monitor (ICM), sought to assess the incidence of AF and other arrhythmia detected using tele-monitoring or interval-based follow-up by an internal cardiologist at the university medical center of Rostock (UMR) or an external cardiologist. Methods The ICM implantation was performed during the inpatient stay in the neurology department, with inclusion and exclusion criteria jointly determined by the neurology and cardiology departments. Cardiologists programmed individual threshold values during ICM implantation, which were designed to instantly trigger an episode being recording and an alarm message being sent out. Outpatient care consisted of tele-monitoring of implants or interval-based follow-up care. Results The indication for ICM implantation was made for 102 patients, 88 of whom underwent ICM implantation, with full documentation available for these 88 study patients. Within a median observation period of 21.5 months, AF occurred in 19 patients, with a median observation time to the event of 7 months. In all cases, AF detection was followed by immediate medical intervention. Comparing patients with and without AF revealed that the median age of the AF group exceeded by 10 years that of the other patients. Stroke recurrence was recorded in five patients, with a median observation time to the event of 9 months. Comparing patients with and without stroke recurrence revealed that the median age in the stroke recurrence group tended to be higher by 14 years. No statistically significant between-group differences were found with regard to integration into tele-monitoring, nor were there any differences identified between outpatient care at the UMR or in the outpatient sector. Conclusions This study confirmed the feasibility of using an interdisciplinary and intersectoral therapeutic approach for monitoring CS patients with implanted ICMs. Further randomized studies are warranted to confirm these encouraging data. An open discussion concerning optimal care forms and opportunities for introducing digitizing care pathways appears warranted.
Profilin-1 Is Expressed in Human Atherosclerotic Plaques and Induces Atherogenic Effects on Vascular Smooth Muscle Cells
Profilin-1 is an ubiquitous actin binding protein. Under pathological conditions such as diabetes, profilin-1 levels are increased in the vascular endothelium. We recently demonstrated that profilin-1 overexpression triggers indicators of endothelial dysfunction downstream of LDL signaling, and that attenuated expression of profilin-1 confers protection from atherosclerosis in vivo. Here we monitored profilin-1 expression in human atherosclerotic plaques by immunofluorescent staining. The effects of recombinant profilin-1 on atherogenic signaling pathways and cellular responses such as DNA synthesis (BrdU-incorporation) and chemotaxis (modified Boyden-chamber) were evaluated in cultured rat aortic and human coronary vascular smooth muscle cells (VSMCs). Furthermore, the correlation between profilin-1 serum levels and the degree of atherosclerosis was assessed in humans. In coronary arteries from patients with coronary heart disease, we found markedly enhanced profilin expression in atherosclerotic plaques compared to the normal vessel wall. Stimulation of rat aortic and human coronary VSMCs with recombinant profilin-1 (10(-6) M) in vitro led to activation of intracellular signaling cascades such as phosphorylation of Erk1/2, p70(S6) kinase and PI3K/Akt within 10 minutes. Furthermore, profilin-1 concentration-dependently induced DNA-synthesis and migration of both rat and human VSMCs, respectively. Inhibition of PI3K (Wortmannin, LY294002) or Src-family kinases (SU6656, PP2), but not PLCγ (U73122), completely abolished profilin-induced cell cycle progression, whereas PI3K inhibition partially reduced the chemotactic response. Finally, we found that profilin-1 serum levels were significantly elevated in patients with severe atherosclerosis in humans (p<0.001 vs. no atherosclerosis or control group). Profilin-1 expression is significantly enhanced in human atherosclerotic plaques compared to the normal vessel wall, and the serum levels of profilin-1 correlate with the degree of atherosclerosis in humans. The atherogenic effects exerted by profilin-1 on VSMCs suggest an auto-/paracrine role within the plaque. These data indicate that profilin-1 might critically contribute to atherogenesis and may represent a novel therapeutic target.
Differential Roles of Cardiomyocyte and Macrophage Peroxisome Proliferator–Activated Receptor γ in Cardiac Fibrosis
Differential Roles of Cardiomyocyte and Macrophage Peroxisome Proliferator–Activated Receptor γ in Cardiac Fibrosis Evren Caglayan 1 2 , Bradley Stauber 1 , Alan R. Collins 3 , Christopher J. Lyon 3 , Fen Yin 1 , Joey Liu 3 , Stephan Rosenkranz 2 , Erland Erdmann 2 , Leif E. Peterson 4 , Robert S. Ross 5 , Rajendra K. Tangirala 1 and Willa A. Hsueh 3 1 Division of Endocrinology, Diabetes and Hypertension, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, California 2 Klinik III für Innere Medizin, Universität zu Köln, Köln, Germany 3 Division of Diabetes, Obesity and Lipids, The Methodist Hospital Research Institute, Houston, Texas 4 Center for Biostatistics, The Methodist Hospital Research Institute, Houston, Texas 5 Division of Cardiology, Department of Medicine, Veterans Affairs Medical Center and University of California, San Diego, San Diego, California Corresponding author: Willa A. Hsueh, wahsueh{at}tmhs.org Abstract OBJECTIVE— Cardiac fibrosis is an important component of diabetic cardiomyopathy. Peroxisome proliferator–activated receptor γ (PPARγ) ligands repress proinflammatory gene expression, including that of osteopontin, a known contributor to the development of myocardial fibrosis. We thus investigated the hypothesis that PPARγ ligands could attenuate cardiac fibrosis. RESEARCH DESIGN AND METHODS— Wild-type cardiomyocyte- and macrophage-specific PPARγ −/− mice were infused with angiotensin II (AngII) to promote cardiac fibrosis and treated with the PPARγ ligand pioglitazone to determine the roles of cardiomyocyte and macrophage PPARγ in cardiac fibrosis. RESULTS— Cardiomyocyte-specific PPARγ −/− mice (cPPARγ −/− ) developed spontaneous cardiac hypertrophy with increased ventricular osteopontin expression and macrophage content, which were exacerbated by AngII infusion. Pioglitazone attenuated AngII-induced fibrosis, macrophage accumulation, and osteopontin expression in both wild-type and cPPARγ −/− mice but induced hypertrophy in a PPARγ-dependent manner. We pursued two mechanisms to explain the antifibrotic cardiomyocyte-PPARγ–independent effects of pioglitazone: increased adiponectin expression and attenuation of proinflammatory macrophage activity. Adenovirus-expressed adiponectin had no effect on cardiac fibrosis and the PPARγ ligand pioglitazone did not attenuate AngII-induced cardiac fibrosis, osteopontin expression, or macrophage accumulation in monocyte-specific PPARγ −/− mice. CONCLUSIONS— We arrived at the following conclusions: 1 ) both cardiomyocyte-specific PPARγ deficiency and activation promote cardiac hypertrophy, 2 ) both cardiomyocyte and monocyte PPARγ regulate cardiac macrophage infiltration, 3 ) inflammation is a key mediator of AngII-induced cardiac fibrosis, 4 ) macrophage PPARγ activation prevents myocardial macrophage accumulation, and 5 ) PPARγ ligands attenuate AngII-induced cardiac fibrosis by inhibiting myocardial macrophage infiltration. These observations have important implications for potential interventions to prevent cardiac fibrosis. Footnotes Published ahead of print at http://diabetes.diabetesjournals.org on 28 May 2008. Readers may use this article as long as the work is properly cited, the use is educational and not for profit, and the work is not altered. See http://creativecommons.org/licenses/by-nc-nd/3.0/ for details. The costs of publication of this article were defrayed in part by the payment of page charges. This article must therefore be hereby marked “advertisement” in accordance with 18 U.S.C. Section 1734 solely to indicate this fact. Accepted May 14, 2008. Received July 5, 2007. DIABETES
Prevalence and Progression of Cognitive Impairment in Atrial Fibrillation Patients after Treatment with Catheter Ablation or Drug Therapy
Purpose. In atrial fibrillation (AF) patients, the effect of catheter ablation or drug therapy on cognition is currently not well investigated. Therefore, we prospectively evaluated AF patients who were either treated 'with drug therapy or underwent catheter ablation for the prevalence and progression of cognitive impairment (CI). Methods. Randomized participants of the CABANA trial (catheter ablation versus antiarrhythmic drug therapy for atrial fibrillation) and the CASTLE-AF (catheter ablation versus standard conventional treatment in patients with left ventricular dysfunction and atrial fibrillation) study were assessed twice within 6 months by Montreal Cognitive Assessment (MoCA) and Mini-Mental State Examination (MMSE) in our institution. Results. Forty-five patients from both trials were investigated, and twenty-eight patients received catheter ablation, whereas seventeen patients received drug therapy for rhythm or rate control. The mean age of the twenty-one CABANA trial patients (AF group) was 68.8 ± 7.0 years and of the twenty-four CASTLE-AF study patients (AF/HF group) was 66.8 ± 8.1 years, respectively. Mean time from ablation/randomization to the first interview was 16.8 ± 11 months in the AF group and 28.3 ± 18.4 months in the AF/HF group, respectively. All patients investigated were classified as cognitively impaired with mean cutoff scores <24 by MoCA. Overall, we could not detect significant differences in medically treated versus catheter ablation patients within both groups in mean MMSE or MoCA scores between the first and the second interview (p>0.09). Moreover, patients who received catheter ablation did not show statistically significant differences in the prevalence or progression of cognitive impairment compared to patients who were treated medically, neither within the two groups nor between AF and AF/HF patients (p>0.05). Conclusions. Prevalence of cognitive impairment in AF patients with comorbidities is substantial. However, in this preliminary prospective study, no apparent impact of AF pretreatment on the prevalence and course of cognitive impairment could be observed.
Impact of Rescue-Thrombolysis during Cardiopulmonary Resuscitation in Patients with Pulmonary Embolism
Cardiac arrest in patients with pulmonary embolism (PE) is associated with high morbidity and mortality. Thrombolysis is expected to improve the outcome in these patients. However studies evaluating rescue-thrombolysis in patients with PE are missing, mainly due to the difficulties of clinical diagnosis of PE. We aimed to determine the success influencing factors of thrombolysis during resuscitation in patients with PE. We analyzed retrospectively the outcome of 104 consecutive patients with confirmed (n = 63) or highly suspected (n = 41) PE and monitored cardiac arrest. In all patients rtPA was administrated for thrombolysis during cardiopulmonary resuscitation. In 40 of the 104 patients (38.5%) a return of spontaneous circulation (ROSC) could be achieved successfully. Patients with ROSC received thrombolysis significantly earlier after CPR onset compared to patients without ROSC (13.6+/-1.2 min versus 24.6+/-0.8 min; p<0.001). 19 patients (47.5%) out of the 40 patients with initially successful resuscitation survived to hospital discharge. In patients with hospital discharge thrombolysis therapy was begun with a significantly shorter delay after cardiac arrest compared to all other patients (11.0+/-1.3 vs. 22.5+/-0.9 min; p<0.001). Rescue-thrombolysis should be considered and started in patients with PE and cardiac arrest, as soon as possible after cardiac arrest onset.
Diagnostic accuracy of NT-proBNP ratio (BNP-R) for early diagnosis of tachycardia-mediated cardiomyopathy: a pilot study
Background When heart failure and tachycardia occur simultaneously, a useful diagnostic tool for early discrimination of patients with benign tachycardia-mediated cardiomyopathy (TMC) versus major structural heart disease (MSHD) is not available. Such a tool is required to prevent unnecessary and wearing diagnostics in patients with reversible TMC. Moreover, it could lead to early additional diagnostics and therapeutic approaches in patients with MSHD. Methods A total of 387 consecutive patients with supraventricular arrhythmia underwent assessment at a single center. Of these patients, 40 fulfilled the inclusion criteria with a resting heart rate ≥100 bpm and an impaired left ventricular ejection fraction <40%. In all patients, successful electrical cardioversion was performed. At baseline, day 1 and weekly for 4 weeks, levels of NT-proBNP and echocardiographic parameters were evaluated. An NT-proBNP ratio (BNP-R) was calculated as a quotient of baseline NT-proBNP/follow-up NT-proBNP. After 4 weeks, cardiac catheterization was performed to identify patients with a final diagnosis of TMC versus MSHD. Results Initial NT-proBNP concentrations were elevated and consecutively decreased after cardioversion in all patients. Multivariate regression and ROC analysis revealed that BNP-R discriminated between patients with TMC versus MSHD independent and superior to all other variables. The area under the ROC curve for BNP-R to detect TMC was 0.90 (95% CI 0.79–1.00; p  < 0.001) after 1 week and 0.995 (95% CI 0.99–1.00; p  < 0.0001) after 4 weeks. One week after cardioversion already, a BNP-R cutoff ≥2.3 was useful for TMC diagnosis indicated by an accuracy of 90%, sensitivity of 84% and specificity of 95%. Conclusion BNP-R was found to be highly accurate for the early diagnosis of TMC.