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Öğe Alterations in right ventricular mechanics in patients with Behcet’s disease(Springer Science and Business Media B.V., 2022) Dinç Asarcıklı, Lale; Sarıtaş, Fatih; Güvenç, Tolga Sinan; Can, Fatma; Sert, Sena; Çetin Güvenc, Rengin; Poyraz, Esra; Ünal, ŞennurManifest myocardial involvement is somewhat rare in patients with Behcet’s disease (BD), although echocardiographic studies suggest that subclinical alterations in left ventricular (LV) contractility is rather common. Data on right ventricular (RV) involvement in BD is rather scarce. This study aims to determine whether RV systolic performance is affected in BD patients, and to understand the clinical and echocardiographic correlates of RV contractility in these patients. Forty-five patients who fulfilled criteria for BD and 45 age and gender matched controls were enrolled. All participants underwent a comprehensive echocardiographic examination, including deformation imaging, to characterize RV mechanics. Conventional morphologic and echocardiographic indicators of RV morphology and function were not different between groups, but RV apical strain and RV free wall strain (FWS) were significantly lower in BD patients as compared to the controls (P < 0.001 and P = 0.02, respectively). The only significant correlates of FWS were tricuspid regurgitation velocity and related indices in healthy controls, while FWS correlated with LV global longitudinal strain (GLS), morphologic measures of left and right atria and ventricles, and with conventional measures of right ventricular contractility. The relationship between FWS and GLS remained statistically significant after adjusting for other clinical and echocardiographic parameters (? = 0.379, P = 0.01). In patients with BD, there is a subclinical alteration in RV contractility and the degree of alteration in the RV systolic performance paralleled that of LV. Thus, present results support the presence of RV involvement in these patients. © 2022, The Author(s), under exclusive licence to Springer Nature B.V.Öğe Comparison of novel Martin/Hopkins and sampson equations for calculation of low-density lipoprotein cholesterol in diabetic patients(ARQUIVOS BRASILEIROS CARDIOLOGIA, 2022) Naser, Abdulrahman; Isgandarov, Khagani; Güvenç, Tolga Sinan; Güvenç, Rengin Çetin; Şahin, MüslümBackground: The accurate determination of low-density lipoprotein cholesterol (LDL-C) is important to reach guidelinere-commended LDL-C concentrations and to reduce adverse cardiovascular outcomes in diabetic patients. The commonly used Friedewald equation (LDL-Cf), gives inaccurate results in diabetic patients due to accompanying diabetic dyslipidemia. Recently two new equations - Martin/Hopkins (LDL-Cmh) and Sampson (LDL-Cs) - were developed to improve the accuracy of LDL-C estimation, but data are insufficient to suggest the superiority of one equation over the other one. Objective: The present study compared the accuracy and clinical usefulness of novel Martin/Hopkins and Sampson equations in diabetic patients. Methods: This study included 402 patients with diabetes. Patients' cardiovascular risk and LDL-C targets were calculated per European guidelines. Calculated LDL-Cmh, LDL-Cs, and LDL-Cf concentrations were compared with direct LDL-C concentration (LDL-Cd) to test agreement between these equations and LDL-Cd. A p-value <0.05 was accepted as statistically significant. Results: Both LDL-Cmh and LDL-Cs had a better agreement with LDL-Cd as compared to LDL-Cf, but no statistical differences were found among novel equations for agreement with LDL-Cd (Cronbach's alpha 0.955 for both, p=1). Likewise, LDL-Cmh and LDL-Cs showed a similar degree of agreement with LDL-Cd in determining whether a patient was in a guideline-recommended LDL-C target (96.3% for LDL-Cmh and 96.0% for LDL- Cs), which were marginally better than LDL-Cf (94.6%). In patients with a triglyceride concentration >400 mg/dl, agreement with LDL-Cd was poor, regardless of the method used. Conclusion: Martin/Hopkins and Sampson's equations show a similar accuracy for calculating LDL-C concentrations in patients with diabetes, and both equations were marginally better than the Friedewald equation.Öğe Coronary flow velocity reserve is reduced in patients with an exaggerated blood pressure response to exercise(Springer, 2022) Baycan, Ömer Faruk; Çelik, Fatma Betül; Güvenç, Tolga Sinan; Atıcı, Adem; Yılmaz, Yusuf; Konal, Oğuz; Ağırbaşlı, Mehmet; Kul, Şeref; Güllü, Hakan; Çalışkan, MustafaCoronary artery disease and cardiovascular mortality are increased in patients with an exaggerated blood pressure response to exercise. The exact cause of this increase remains unknown, but previous studies have indicated the presence of endothelial dysfunction in peripheral arteries and subclinical atherosclerosis in these patients. The present study aimed to clarify whether coronary microvascular dysfunction is also present in patients with exaggerated blood pressure response to exercise. A total of 95 patients undergoing exercise testing were consecutively enrolled. Flow-mediated vasodilatation and carotid intima-media thickness were measured using standardized methods. A transthoracic echocardiography examination was performed to measure coronary flow velocity reserve. Patients with an exaggerated blood pressure response to exercise had significantly lower coronary flow velocity reserve than the controls (2.06 (1.91–2.36) vs. 2.27 (2.08–2.72), p = 0.004), and this difference was caused by a reduction in hyperemic flow velocity (57.5 (51.3–61.5) vs. 62.0 (56.0–73.0), p = 0.004) rather than a difference in basal flow (26.5 (22.3–29.8) vs. 26.0 (24.0–28.8), p = 0.95). Patients with an exaggerated blood pressure response to exercise also had a significantly greater carotid intima-media thickness and significantly lower flow-mediated vasodilatation than controls. However, an exaggerated blood pressure response to exercise remained a significant predictor of coronary microvascular dysfunction after adjusting for confounders (OR: 3.60, 95% CI: 1.23–10.54, p = 0.02). Patients with an exaggerated blood pressure response to exercise show signs of coronary microvascular dysfunction, in addition to endothelial dysfunction and subclinical atherosclerosis. This finding might explain the increased risk of coronary artery disease and cardiovascular mortality in these patients.Öğe Coronary microvascular dysfunction is common in patients hospitalized with COVID-19 infection(Wiley, 2022) Atıcı, Adem; Çalışkan, Mustafa; Baycan, Ömer Faruk; Çelik, Fatma Betül; Güvenç, Tolga Sinan; Çağ, Yasemin; Konal, Oğuz; Bilgili, Ümmühan Zeynep; Ağırbaşlı, Mehmet Ali; Irgı, TuğçeBackground and Aims: Microvascular disease is considered as one of the main drivers of morbidity and mortality in severe COVID-19, and microvascular dysfunction has been demonstrated in the subcutaneous and sublingual tissues in COVID-19 patients. The presence of coronary microvascular dysfunction (CMD) has also been hypothe-sized, but direct evidence demonstrating CMD in COVID-19 patients is missing. In the present study, we aimed to investigate CMD in patients hospitalized with COVID-19, and to understand whether there is a relationship between biomarkers of myocardial injury, myocardial strain and inflammation and CMD.Methods:39 patients that were hospitalized with COVID-19 and 40 control subjects were included to the present study. Biomarkers for myocardial injury, myocardial strain, inflammation, and fibrin turnover were obtained at admission. A comprehen-sive echocardiographic examination, including measurement of coronary flow veloc -ity reserve (CFVR), was done after the patient was stabilized.Results:Patients with COVID-19 infection had a significantly lower hyperemic cor -onary flow velocity, resulting in a significantly lower CFVR (2.0 ± 0.3 vs. 2.4 ± 0.5, p< .001). Patients with severe COVID-19 had a lower CFVR compared to those with moderate COVID-19 (1.8 ± 0.2 vs. 2.2 ± 0.2, p< .001) driven by a trend toward higher basal flow velocity. CFVR correlated with troponin (p= .003, r: ?.470), B- type natriu-retic peptide (p< .001, r: ?.580), C- reactive protein (p< .001, r: ?.369), interleukin-6 (p< .001, r: ?.597), and d- dimer (p< .001, r: ?.561), with the three latter biomarkers having the highest areas-under- curve for predicting CMD.Conclusions:Coronary microvascular dysfunction is common in patients with COVID-19 and is related to the severity of the infection. CMD may also explain the “cryptic” myocardial injury seen in patients with severe COVID-19 infection.Öğe Formulating and characterizing an exosome-based dopamine carrier system(Jove, 2022) Naser, Abdulrahman; Isgandarov, Khagani; Güvenç, Tolga Sinan; Ekmekçi, Ahmet; Güvenç, Rengin Çetin; Şahin, Müslüm; Gündüz, Sabahattin; Şahin, MüslümExosomes between 40 and 200 nm in size constitute the smallest subgroup of extracellular vesicles. These bioactive vesicles secreted by cells play an active role in intercellular cargo and communication. Exosomes are mostly found in body fluids such as plasma, cerebrospinal fluid, urine, saliva, amniotic fluid, colostrum, breast milk, joint fluid, semen, and pleural acid. Considering the size of exosomes, it is thought that they may play an important role in central nervous system diseases because they can pass through the blood-brain barrier (BBB). Hence, this study aimed to develop an exosome-based nanocarrier system by encapsulating dopamine into exosomes isolated from Wharton's jelly mesenchymal stem cells (WJ-MSCs). Exosomes that passed the characterization process were incubated with dopamine. The dopamine-loaded exosomes were recharacterized at the end of incubation. Dopamine-loaded exosomes were investigated in drug release and cytotoxicity assays. The results showed that dopamine could be successfully encapsulated within the exosomes and that the dopamine-loaded exosomes did not affect fibroblast viability.Öğe Gut microbiota-derived metabolite trimethylamine N-oxide and biomarkers of inflammation are linked to endothelial and coronary microvascular function in patients with inflammatory bowel disease(Elsevier, 2022) Kul, Sere; Caliskan, Zuhal; Güvenç, Tolga Sinan; Celik, Fatma Betul; Sarmis, Abdurrahman; Atici, AdemBackground: Inflammatory bowel disease (IBD), which is an umbrella term used for ulcerative colitis (UC) and Crohn's disease (CD), is associated with an increased risk for atherosclerotic cardiovascular disease (CVD). We aimed to investigate the association of local and systemic biomarkers of inflammation and gut microbiota-derived metabolite trimethylamine N-oxide (TMAO) with endothelial and coronary microvascular dysfunction in IBD. Methods: A total of 56 patients with IBD (20 with UC and 36 with CD) and 34 age and gender matched controls were included. For all participants, samples were collected to analyze faecal calprotectin, and TMAO concentrations. Ultrasound-based examinations were done to measure flow-mediated vasodilatation (FMD) and coronary flow velocity reserve (CFVR). Results: Patients with IBD had lower CFVR (2.07 (1.82–2.40)) and FMD (8.7 ± 3.7) as compared to controls (2.30 (2.07–2.74), p = 0.005 and 11.9 ± 6.8, p = 0.03). In patients with IBD, TMAO concentration (r = ?0.30, p = 0.03), C-reactive protein (r = ?0.29, p = 0.03) and WBC count (r = ?0.37, p = 0.006) had a significant negative correlation with CFVR, and TMAO (? = ?0.27, 95 % CI: ?0.23 to ?0.02) and WBC count (? = ?0.31, 95 % CI: ?0.56 to ?0.06) were significant predictors of CFVR after multivariate adjustment. None of the biomarkers of inflammation or TMAO showed significant correlations with FMD. In patients with UC, TMAO showed a significant correlation with both CFVR (r = ?0.55, p = 0.01) and FMD (r = ?0.60, p = 0.005) while only WBC count had a statistically significant correlation with CFVR (r = ?0.49, p = 0.004) in patients with CD. Conclusions: Gut microbiota-derived metabolite TMAO and biomarkers of systemic inflammation are associated with measures of endothelial/coronary microvascular dysfunction in patients with IBD. © 2022Öğe Lack of right ventricular hypertrophy is associated with right heart failure in patients with left ventricular failure(Springer, 2022) Naser, Abdulrahman; Isgandarov, Khagani; Güvenç, Tolga Sinan; Ekmekçi, Ahmet; Gündüz, Sabahattin; Güvenç, Rengin Çetin; Şahin, MüslümPresence of right heart failure (RHF) is associated with a worse prognosis in patients with left ventricular failure (LVF). While the cause of RHF secondary to LVF is multifactorial, an increased right ventricular (RV) afterload is believed as the major cause of RHF. However, data are scarce on the adaptive responses of the RV in patients with LVF. Our aim was to understand the relationship of right ventricular hypertrophy (RVH) with RHF and RV systolic and diastolic properties in patients with LVF. 55 patients with a left ventricular ejection fraction of 40% or less were included in the present study. A comprehensive two-dimensional transthoracic echocardiographic examination was done to all participants. 12 patients (21.8%) had RHF, and patients with RHF had a signifcantly lower right ventricular free wall thickness (RVFWT) as compared to patients without RHF (5.3±1.7 mm vs. 6.6±0.9 mm, p=0.02) and the diference remained statistically signifcant after adjusting for confounders (?x?:1.34 mm, p=0.002). RVFWT had a statistically signifcant correlation with tricuspid annular plane systolic excursion (r=0.479, p<0.001) and tricuspid annular lateral systolic velocity (r=0.360, p=0.007), but not with the indices of the RV diastolic function. None of the patients with concentric RVH had RHF, while 22.2% of patients with eccentric RVH and 66.7% of patients without RVH had RHF (p<0.01 as compared to patients with concentric RVH). In patients with left ventricular systolic dysfunction, absence of RVH was associated with worse RV systolic performance and a signifcantly higher incidence of RHFÖğe Thrombolysis in myocardial infarction risk index predicts one-year mortality in patients with heart failure: an analysis of the SELFIE-TR study(KARGER, 2022) Güvenç, Rengin Çetin; Güvenç, Tolga Sinan; Ural, Dilek; Cavusoglu, Yuksel; Yilmaz, Mehmet BirhanObjective: Predicting outcomes is an essential part of evaluation in patients with heart failure (HF). While there are multiple individual laboratory and imaging variables, as well as risk scores available for this purpose, they are seldom useful during the initial evaluation. In this analysis, we aimed to understand predictive usefulness of Thrombosis in Myocardial Infarction Risk Index (TIMI-RI), a simple index that is calculated at bedside using three commonly available variables, using data from a multicenter HF registry. Subjects and Methods: A total of 728 patients from 23 centers were included to this analysis. Data on hospitalizations and mortality were collected by direct interviews, phone calls and electronic databases. TIMI-RI was calculated as defined before. Patients were divided into three equal tertiles to perform analyses. Results: Rehospitalization for HF was significantly higher in patients within the 3rd tertile, and 33.5% of patients within the 3rd tertile were dead within one-year follow up as compared to 14.5% of patients within the 1st tertile and 15.6% patients within the 2nd tertile (p<0.001, log-rank p<0.001 for pairwise comparisons on survival analysis). A TIMI-RI higher than 33 had a negative predictive value of 84.8% and a positive predictive value of 33.8% for prediction of one-year mortality. This predictive usefulness was independent of other demographic, examination and clinical variables (OR:1.74, 95%CI:1.05-2.86, p=0.036). Conclusion: TIMI-RI is a simple index that predicts one-year mortality in patients with HF, and it could be useful for rapid evaluation and triage of HF patients at the time of initial contact.Öğe Transcutaneous puncture and successfully retrieval of undeflated peripheral angioplasty balloon(NLM (Medline), 2022) Isgandarov, Khagani; Naser, Abdulrahman; Şahin, Müslüm; Güvenç, Tolga SinanPercutaneous transluminal angioplasty has gained increasing popularity in the treatment of peripheral artery disease. However, the increase in the frequency of this procedure also increases the risk of complications. Percutaneous transluminal angioplasty has serious and general complications in terms of device and technique at puncture and dilatation sites. In this case, we describe the easy and practical management of deflating an undeflated ballon in the right superficial femoral artery.
