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Öğe A comprehensive review of the diagnosis and management of mitral paravalvular leakage(Turkish Soc Cardiology, 2020) Gürsoy, Mustafa Ozan; Güner, Ahmet; Kalçık, Macit; Bayam, Emrah; Özkan, MehmetMitral paravalvular leaks (PVLs) commonly occur in patients with prosthetic valves. Paravalvular defects may be clinically inconsequential and may aggravate hemolysis or cause heart failure through regurgitation. Accordingly, patients may eventually require intervention such as redo surgery or a transcatheter closure of the defects. The introduction of purpose-specific closure devices and new steerable catheters has opened a new frontier for the transcatheter PVL closure. This mode of treatment is an initial therapy in most centers with experienced structural heart team. However, head-to-head data comparing two treatment modalities (surgery and transcatheter closure) are limited, and the world-wide experience is based on nonrandomized studies. Multimodality imaging, including three-dimensional transesophageal echocardiography, facilitates the delineation of mitral PVLs and provides essential data that aids the communication between the members of the structural heart team. In the near future, the success of interventional therapies will most probably increase in patients with mitral PVLs with the introduction of hybrid imaging modalities (echocardiography, cardiac computed tomography, and fluoroscopy). In conclusion, this paper summarizes the etiopathogenesis, clinical characteristics, diagnosis, and treatment of mitral PVLs.Öğe A global perspective on mechanical prosthetic heart valve thrombosis: Diagnostic and therapeutic challenges(Turkish Society of Cardiology, 2019) Gürsoy, Mustafa Ozan; Kalçık, Macit; Yesin, Mahmut; Karakoyun, Süleyman; Bayam, Emrah; Gündüz, Sabahattin; Özkan, MehmetProsthetic valve thrombosis is one of the major causes of primary valve failure, which can be life-threatening. Multimodality imaging is necessary for determination of leaflet immobilization, cause of underlying pathology (thrombus versus pannus or both), and whether thrombolytic therapy attempt in the patient would be successful or surgery is needed. Current guidelines for the management of prosthetic valve thrombosis lack definitive class I recommendations due to lack of randomized controlled trials, and usually leave the choice of treatment to the clinician’s experience. In this review, we aimed to summarize the pathogenesis, diagnosis, and management of mechanical prosthetic valve thrombosis. (Anatol J Cardiol 2016; 16: 980-9). © 2016 by Turkish Society of Cardiology.Öğe Anticoagulation strategy and management of patients with mechanical prosthetic heart valves during pregnancy(Elsevier Ltd, 2019) Kalkan, Semih; Güner, Ahmet; Kalçık, Macit; Bayam, Emrah; Özkan, MehmetTo the Editor,We have read with great interest the article by Komatsu et al.entitled “A case of thrombolytic therapy with recombinant tissueplasminogen activator for mechanical valve thrombosis at 9 weeksof pregnancy in a Japanese woman” [1].Öğe Characteristic localization patterns of thrombus on various brands of bileaflet mitral mechanical heart valves as assessed by three-dimensional transesophageal echocardiography and their relationship with thromboembolism(Springer, 2021) Sarı, Munevver; Bayram, Zübeyde; Aytürk, Mehmet; Bayam, Emrah; Kalkan, Semih; Güner, Ahmet; Özkan, Mehmet; Kalçık, Macit; Gürsoy, Mustafa Ozan; Gündüz, SabahattinThree-dimensional transesophageal echocardiography (3D-TEE) provides detailed images of prosthetic valve thrombosis (PVT). However, data regarding PVT localization patterns based on 3D-TEE and their association with clinical findings among various bileaflet mitral prosthetic valve brands is lacking. The locations of thrombi were classified into 4 groups according to hinge and annulus involvement based on 3D-TEE: ring-like PVT involving entire mitral annulus (type-1), PVT involving peri-hinge(s) region and extends through some part of the annulus (type-2), PVT involving mitral annulus without involving hinge(s) region (type-3), and PVT involving only (peri)hinge(s) area (type-4). This study was conducted in 265 patients (male: 71, mean age: 46.3 +/- 12.7 years) with mitral PVT, including 150 St Jude Medical (SJM), 65 Carbomedics, 29 Medtronic ATS open-pivot, and 21 Sorin bileaflet mechanical valves. There was a significant difference in most common PVT localization patterns between different prosthetic valves (type-1 for Carbomedics and Sorin; type-2 for SJM and type-3 for ATS valves; p < 0.001). Additionally, PVT involving only (peri)hinge region(s) (type-4) was mostly observed in patients with SJM valves (18%). (Peri)hinge(s) area involvement was observed in the majority of study patients (78.1%). In patients who presented with thromboembolism, the most common PVT localization pattern was type-1 (53%). Increased age, low international normalized ratio on admission, PVT with a mobile part > 2 mm, type-1 and type-4 PVT were associated with thromboembolic events. In conclusion, thrombus can be displayed in distinct locations in several types of bileaflet mechanical valves due to different design, hinge and pivot mechanisms, which can be complicated with thromboembolic events.Öğe Comparison of different anticoagulation regimens in pregnant patients with mechanical prosthetic heart valves(Oxford Univ Press, 2017) Kalçık, Macit; Bayam, Emrah; Yesin, Mahmut; Gündüz, Sabahattin; Gürsoy, Mustafa Ozan; Karakoyun, Süleyman; Özkan, Mehmet[Abstract Not Available]Öğe Comparison of Different Anticoagulation Regimens Regarding Maternal and Fetal Outcomes in Pregnant Patients With Mechanical Prosthetic Heart Valves (from the Multicenter ANATOLIA-PREG Registry)(Excerpta Medica Inc-Elsevier Science Inc, 2020) Güner, Ahmet; Kalçık, Macit; Gürsoy, Mustafa Ozan; Gündüz, Sabahattin; Astarcıoğlu, Mehmet Ali; Bayam, Emrah; Özkan, MehmetMechanical prosthetic heart valves (MPHVs) are highly thrombogenic, and a pregnancyinduced procoagulant status increases the risk of MPHV thrombosis. Despite numerous case reports, 2 major registries and meta-analyses/systematic reviews, optimal anticoagulation therapy during pregnancy remains controversial. The goal of this study was to evaluate different anticoagulation regimens in pregnant patients with MPHVs. The outcomes of anticoagulation regimens were assessed retrospectively in pregnant women (110 women; 155 pregnancies) with MPHVs. The study population was divided into 5 groups according to anticoagulation regimens used; high-dose warfarin (>5 mg/d) throughout pregnancy (group 1), low-dose warfarin (<= 5 mg/d) throughout pregnancy (group 2), low molecular weight heparin (LMWH) throughout pregnancy (group 3), first trimester LMWH, 2nd and 3rd trimester warfarin (group 4), first 2 trimester LMWH, and 3rd trimester warfarin (group 5). Of 155 pregnancies, 55 (35%) resulted in fetal loss; whereas 41 (27%) cases with abortion (miscarriage and therapeutic) and 14 (9%) stillbirths occurred. The comparison of the groups showed that the whole abortion rates including therapeutic abortion were significantly higher in Group 1, and lower in groups 3 and 5 (p <0.001). However, miscarriage rates were similar between the groups. A total of 53 pregnancies (34%) suffered from prosthetic valves thrombosis (PVT) during pregnancy or in the postpartum period. Group 2 had significantly lower rates of PVT than the other groups (p <0.001). In conclusion, the current data suggests that there is no optimal therapy, and that all managements have advantages and disadvantages. Low-dose warfarin (<= 5 mg/day) regimen with therapeutic international normalized ratio levels may provide effective maternal protection throughout pregnancy with acceptable fetal outcomes. (C) 2020 Elsevier Inc. All rights reserved.Öğe Echocardiographic measurement of epicardial adipose tissue thickness in patients with microvascular angina(Akademiai Kiado Zrt, 2019) Kalçık, Macit; Yesin, Mahmut; Güner, Ahmet; Bayam, Emrah; Yetim, Mücahit; Doğan, Tolga; Karavelioğlu, YusufIntroduction: Impaired coronary microcirculation, inflammation, and endothelial dysfunction were reported etiological factors for microvascular angina (MVA). Recently, increased epicardial adipose tissue (EAT) thickness has been associated with hypertension, metabolic syndrome, and coronary artery disease in general population. In this study, we aimed to evaluate the EAT thickness in patients with MVA. Methods: This study enrolled 200 patients (83 males; mean age: 55.4 +/- 8.2 years) who have been diagnosed with MVA and 200 controls (89 males; mean age: 54.4 +/- 8.5 years). All patients underwent transthoracic echocardiography, and EAT thickness was measured from a parasternal long-axis view as the hypoechoic space on the right ventricular free wall. Results: The mean EAT thickness was significantly higher in MVA patients than the controls (5.5 +/- 1.1 vs. 4.9 +/- 0.7 mm; p < 0.001). Multiple logistic regression analysis showed that increased EAT thickness was an independent predictor of MVA (OR = 1.183, 95% CI = 1.063-1.489; p = 0.023). In receiver operating characteristic curve analyses, EAT thickness above 5.3 mm predicted MVA with a sentivity of 68% and a specificity of 63% (AUC = 0.711, 95% CI = 0.659-0.762; p < 0.001). Conclusions: The EAT thickness was observed significantly higher in MVA patients as compared to controls. Increased EAT thickness may be associated with mechanisms that play a major role in the pathogenesis of MVA.Öğe Evaluation of the potential predictors of embolism in patients with left atrial myxoma(Blackwell Publishing Inc., 2019) Kalçık, Macit; Bayam, Emrah; Güner, Ahmet; Küp, Ayhan; Kalkan, Semih; Yesin, Mahmut; Gürsoy, Mustafa Ozan; Gündüz, Sabahattin; Karakoyun, Süleyman; Özkan, MehmetIntroduction: Cardiac myxomas are the most common primary intracardiac tumors. Although myxomas are histologically benign, they are potentially dangerous due to potential risk of systemic and cerebral embolism. In this study, we aimed to investigate the potential predictors of embolism in patients with left atrial myxoma. Methods: This single-center retrospective study enrolled 93 patients (mean age: 52.9 ± 15.3 years, female: 70 [75.3%]) with left atrial myxomas between 2014 and 2018. The patients were classified into two groups (embolic vs nonembolic) to investigate possible predictors of embolism. Demographic, laboratory, and echocardiographic parameters were recorded into a dataset and compared between patients with and without embolism. Results: The study population was composed of 13 (14%) patients in embolic (11 cerebrovascular and 2 peripheral) and 80 (86%) patients in nonembolic group. Demographic and laboratory parameters were similar between the groups. Tumor sizes were significantly higher in the embolic group than in the nonembolic group (5.59 ± 1.08 vs 4.29 ± 0.61; P = 0.001). By multivariate analysis, increased tumor size, increased left atrial diameter, and the presence of atrial fibrillation and irregular tumor surface were identified as independent predictors of embolism. In ROC curve analyses, tumor size above 4.6 cm predicted embolism with a sensitivity of 77% and a specificity of 73% (AUC: 0.858; 95% CI: 0.752–0.964; P < 0.001). Conclusion: The presence of atrial fibrillation, irregular tumor surface, increased tumor size, and increased left atrial diameter is associated with increased risk of embolism in patients with left atrial myxoma. Early surgery should be scheduled for such patients due to increased potential for embolism. © 2019 Wiley Periodicals, Inc.Öğe Evaluation of the relationship between platelet indices and spontaneous echo contrast in patients with mitral prosthetic heart valves(2020) Kalçık, Macit; Sayar, Ahmet Güner; Bayam, Emrah; Yesin, Mahmut; Kalkan, Semih; Gürsoy, Mustafa Ozan; Özkan, Mehmet AkifObjective: Spontaneous echo contrast (SEC) is defined as dynamic, smoke-like echoes within the cardiac cavities with a characteristic swirling motion seen on echocardiography. Clinical studies have demonstrated that SEC is a risk factor for left atrial thrombus formation and an important indicator for potential systemic embolism. Platelet indices have been associated with the presence of SEC in patients with mitral stenosis. The aim of this study was to investigate the relationship between platelet indices and SEC in patients with prosthetic heart valves. Methods: A total of 89 patients [female: 38 (42.4%); median age: 52 years (range: 36-67 years)] with SEC formation in the left atrium, and 257 control subjects [female: 123 (47.5%); median age: 56 years (range: 45-65 years)] without SEC formation were enrolled. All of the patients were evaluated by using transthoracic and transesophageal echocardiography. Laboratory tests including complete blood count and biochemical parameters were analyzed. Results: Patients with SEC formation had more frequent atrial fibrillation, higher left atrial diameter (LAD) and lower left ventriular ejection fraction values. Platelet indices including platelet count, platelet distribution width, mean platelet volume, and plateletcrit did not differ between the groups. Increased LAD was detected as the only independent predictor of SEC development. Conclusion: Platelet indices were not found to be associated with the presence of SEC formation in the left atrium among patients with mitral prosthetic valves. Therefore, the use of platelet indices alongside known echocardiographic and clinical risk factors to predict SEC development in patients with a mitral prosthesis is debatable.Öğe Identification of mechanical prosthetic heart valves based on distinctive cinefluoroscopic and echocardiographic markers(Sage Publications Ltd, 2019) Kalçık, Macit; Güner, Ahmet; Yesin, Mahmut; Bayam, Emrah; Kalkan, Semih; Gündüz, Sabahattin; Özkan, MehmetThe past 65 years have witnessed remarkable progress in the development of safe, hemodynamically favorable mechanical heart valves. Today, there are a large number and variety of prostheses in use and many prostheses have been used for a while and then discontinued. When patients lack reliable information about their heart valve prostheses, identification of valve model becomes difficult even for specialized physicians in this area. A combination of cinefluoroscopy and echocardiography makes it possible to provide accurate and detailed information regarding identification of prosthetic valve models. Fluoroscopic examination is a useful technique to evaluate patients following mechanical heart valve replacement. However, transthoracic echocardiography and transesophageal echocardiography have almost replaced cinefluoroscopy in the evaluation of prosthetic heart valves. Especially, real-time three-dimensional transesophageal echocardiography provides distinctive images of prosthetic heart valves, particularly for those in the mitral position. A large body of literature has been published to familiarize physicians with the radiological appearance of numerous mechanical prostheses. However, there is a lack of data regarding the identification of prosthetic valve models based on echocardiographic appearance. In this review, we aimed to describe distinctive echocardiographic and cinefluoroscopic markers for identifying the type and brand of several commonly used mechanical prosthetic heart valves.Öğe Increased Ventricular Activation Time in Patients with the Diagnosis of Cardiac Syndrome X(2019) Kalçık, Macit; Bayam, Emrah; Güner, Ahmet; Yesin, Mahmut; Yetim, Mücahit; Doğan, Tolga; Karavelioğlu, Yusuf; Bekar, LütfüIntroduction: Cardiac syndrome X (CSX) is defined as typical angina with detectable ischaemia on noninvasive stress tests without any evidence of coronary artery stenosis during coronary angiography. Impaired coronary microcirculation, inflammation and endothelial dysfunction are accepted aetiological factors for CSX. The ventricular activation time (VAT) has been reported to be prolonged in myocardial ischaemia due to the conduction delay in the Purkinje fibres and the myocytes. In this study, we aimed to investigate the electrocardiographic parameters including VAT in patients with CSX. Patients and Methods: This study enrolled 120 patients (mean age, 54.7 ± 8.6 years; male, 53) diagnosed with CSX and 130 healthy controls (mean age, 53.3 ± 8.9; male, 66) without ischaemia. All patients underwent electrocardiography and transthoracic echocardiography. VAT was defined as the interval from the beginning of the QRS complex until the peak of the R or R’ wave. Results: There was no significant difference in terms of demographic, laboratory and echocardiographic parameters between CSX patients and controls. Comparison of electrocardiographic parameters yielded that there was no significant difference in terms of the heart rate, P-wave duration, PR interval, QT and corrected QT intervals between the groups. However, the QRS duration (95.1 ± 13.8 vs. 90.4 ± 12.7 msec; p= 0.006) and VAT (34.8 ± 5.7 vs. 29.2 ± 5.6 msec; p< 0.001) were significantly higher in patients with CSX. Conclusion: The present study demonstrated that QRS duration and VAT were prolonged significantly in patients with CSX. This prolongation may be due to the presence of impaired microvascular perfusion and ischaemia-induced conduction delay.Öğe Management of an acute ischemic stroke during thrombolytic treatment in a pregnant patient with prosthetic valve thrombosis(Akademiai Kiado Rt., 2017) Kalçık, Macit; Yesin, Mahmut; Bayam, Emrah; Gürsoy, Mustafa Ozan; Güner, Ahmet; Gündüz, Sabahattin; Özkan, MehmetProsthetic valve thrombosis (PVT) is a life-threatening complication in pregnant women with mechanical prosthetic heart valves. Thrombolytic therapy (TT) has evolved as an effective treatment alternative to surgery, which is associated with very high maternal and fetal mortality and morbidity in these patients. Acute ischemic stroke may rarely occur during TT for PVT. Here, we present a pregnant patient who was complicated with cerebral thromboembolism during TT for PVT and successfully managed with continuation of TT. © 2017 The Author(s).Öğe Management of prosthetic valve thrombosis complicated by ischemic stroke in pregnancy(Elsevier Espana Slu, 2019) Güner, Ahmet; Kalçık, Macit; Bayam, Emrah; Kalkan, Semih; Özkan, MehmetTo the Editor, We have recently read with great interest the article by Morgado et al. entitled ‘‘A pregnant woman with a prosthetic mechanical valve’’.1Öğe Noninvasive diagnostic tools available for discrimination pannus from thrombus in patients with prosthetic valve dysfunction(Blackwell Publishing Inc., 2019) Güner, Ahmet; Kalçık, Macit; Gündüz, Sabahattin; Yesin, Mahmut; Bayam, Emrah; Kalkan, Ali Kemal; Kalkan, Semih; Özkan, MehmetWe have recently read with great interest the article by Barroso Freitas?Ferraz et al1 entitled “Prosthetic aortic valve thrombosis: To fibrinolyse or not to fibrinolyse? That is the question!”. The authors reported a case of aortic prosthetic valve dysfunction (PVD), which was successfully treated surgically. We congratulate the authors for achieving a successful outcome in such a high?risk patient. However, we would like to discuss the importance of noninvasive diagnostic tools for differentiation of prosthetic valve thrombus and pannus, which are the major causes of PVD, before surgical treatment.Öğe Normal reference values for mechanical mitral prosthetic valve inner diameters and areas assessed by two-dimensional and real-time three-dimensional transesophageal echocardiography(Springer, 2021) Kalçık, Macit; Özkan, Mehmet; Gündüz, Sabahattin; Gürsoy, Mustafa Ozan; Yesin, Mahmut; Bayam, Emrah; Tanboğa, Halil IbrahimIt was previously observed that two dimensional (2D) Doppler derived and real-time three-dimensional (RT-3D) directly measured valve areas were smaller than reported manufacturer sizes. It may be helpful to obtain the ranges of inner diameters (IDs) and the geometric orifice area (GOA) during evaluation of prosthetic mitral valves. In this study, we aimed to provide reference dimensional parameters of bileflet mitral mechanical prosthetic valves. Patients with recent mitral valve replacement were examined by 2D and RT-3D transesophageal echocardiography (TEE) in the early postoperative period when the presence of pannus overgrowth was unlikely. Measurements of 2D IDs, 3D hinge to hinge (HHD) and edge to edge diameters (EED) and 3D GOA were obtained and compared with reported manufacturer sizes and areas. This study enrolled 126 patients with mitral prosthetic valves (38 ATS, 42 Carbomedics, 46 St. Jude Medical, all bileaflet). The measured 2D and 3D IDs and GOA were significantly smaller than reported manufacturer sizes in the majority of the valve sizes. This RT-3D TEE-guided study provides ranges of reference values for directly measured IDs and GOA of the three most commonly used mechanical mitral prosthetic valve types for the first time in a relatively large series.Öğe Oscillating left atrial appendage in a massive pericardial effusion due to severe paravalvular leakage after mitral valve replacement(Taylor and Francis Ltd., 2017) Yesin, Mahmut; Kalçık, Macit; Çağdaş, Metin; Karakoyun, Süleyman; Bayam, Emrah; Özkan, MehmetA 36-year-old female patient was referred to our hospital with a transient ischaemic attack (TIA) that had occurred three days before and with progressive dyspnoea for about one week.Öğe Relationship between heparanase levels and prosthetic valve thrombosis: clinical implications(Oxford Univ Press, 2017) Bayam, Emrah; Kalçık, Macit; Yesin, Mahmut; Numanoğlu Gündüz, Sinem; Gürsoy, Mustafa Ozan; Karakoyun, Süleyman; Özkan, Mehmet[Abstract Not Available]Öğe Relationship between P wave peak time and coronary artery disease severity in non-ST elevation acute coronary syndrome(Urban & Vogel, 2021) Bayam, Emrah; Yıldırım, Ersin; Kalçık, Macit; Karaduman, Ahmet; Kalkan, Semih; Güner, Ahmet; Uyan, CihangirBackground. Early diagnosis of non-ST elevation acute coronary syndrome (NSTEACS) and prediction of the severity of current coronary artery disease (CAD) play a major role in patient prognosis. Electrocardiography has a unique value in the diagnosis and provides prognostic information on patients with NSTE-ACS. In the present study, we aimed to examine the relationship between P wave peak time (PWPT) and the severity of CAD in patientswith NSTE-ACS. Methods. A total of 132 consecutive patients (female: 35.6%; mean age: 60.1 +/- 11.6 years) who were diagnosed with NSTE-ACS were evaluated retrospectively. Gensini scores (GSs) were used to define the angiographic characteristics of the coronary atherosclerotic lesions. The patients were divided into two groups according to the GS. The PWPT was defined as the duration between the beginning and the peak of the P wave, and R wave peak time (RWPT) was defined as the duration between the beginning of the QRS complex and the peak of the R wave. Results. There were 59 (44.6%) patients in the high-GS group (GS =25) and 73 (55.3%) patients in the low-GS group (GS <25). Presence of diabetesmellitus, low left ventricular ejection fraction, and high RWPT and PWPT were identified as predictors of a high GS in the study population. There was no significant difference between the area under the curves of PWPT and RWPT for predicting the severity of CAD (0.663 vs. 0.623, respectively; p= 0.573). Conclusion. The present study found that both PWPT and RWPT on admission electrocardiography were associated with the severity and complexity of CAD in patients with NSTE-ACS.Öğe Sequential combination of different thrombolytic therapy regimens in the management of patients with prosthetic valve thrombosis and stuck valves(Oxford Univ Press, 2019) Kalçık, Macit; Güner, Ahmet; Bayam, Emrah; Kalkan, Semih; Yesin, M.; Gürsoy, Mustafa Ozan; Özkan, Mehmet[Abstract Not Available]Öğe Status of the epicardial coronary arteries in non-ST elevation acute coronary syndrome in patients with mechanical prosthetic heart valves (from the TROIA-ACS Trial)(Elsevier Inc., 2018) Yesin, Mahmut; Karakoyun, Süleyman; Kalçık, Macit; Gürsoy, Mustafa Ozan; Gündüz, Sabahattin; Astarcıoğlu, Mehmet Ali; Bayam, Emrah; Cerşit, Sinan; Güner, Ahmet; Özkan, MehmetCoronary thromboembolism (CE) is a rare cause of prosthetic valve derived complications. This study investigates the diagnosis and treatment strategies for non-ST elevation acute coronary syndrome (NSTEACS) in patients with prosthetic heart valves. Forty-eight NSTEACS patients with prosthetic heart valves (mitral:27; aortic:14; mitral+aortic:7) were included in this study. All patients underwent transthoracic and transesophageal echocardiographic examination and coronary angiography. Normal coronary angiographic findings, or visible trombus in one of the coronary arteries, international normalized ratio <2, concomitant prosthetic valve thrombosis (PVT) and absence of multivessel atherosclerotic disease favored CE rather than atherothrombosis. Thrombolytic therapy (TT) with low-dose slow-infusion of tissue type plasminogen activator was used in patients with suspected CE and/or PVT. Coronary angiography demonstrated normal coronary arteries in 26 patients, CE in 16 patients and coronary atherosclerosis in 6 patients. Transesophageal echocardiography revealed obstructive PVT in 9 and nonobstructive PVT in 28 patients whereas 11 patients had normally functioning prostheses. TT was administered to 24 patients with PVT and/or CE. In these patients, TT was successful in 19 patients, partially successful in 4 patients and failed in 1 patient. In conclusion, NSTEACS in patients with prosthetic heart valves is more likely to be associated with PVT derived CE rather than atherosclerosis. TT with low-dose slow infusion of type plasminogen activator has proved its efficacy and safety in patients with CE and/or PVT. © 2018 Elsevier Inc.
