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Dive into the research topics where Andrzej Siniawski is active.

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Featured researches published by Andrzej Siniawski.


The Cardiology | 2006

Evaluation of Exercise Capacity with Cardiopulmonary Exercise Testing and Type B Natriuretic Peptide Concentrations in Adult Patients with Patent Atrial Septal Defect

Olga Trojnarska; Andrzej Szyszka; Adrian Gwizdała; Zofia Oko-Sarnowska; Sławomir Katarzyński; Andrzej Siniawski; Ewa Chmara; Andrzej Cieslinski

Adults with patent atrial septal defect (ASD) usually find their exercise capacity satisfactory, and therefore hesitate to accept proposed surgical treatment of the heart disease. The aim of our study was to evaluate both the exercise capacity, using the cardio-pulmonary stress test, and brain natriuretic peptide (BNP) levels in asymptomatic adults with ASD. Thirty-six patients with patent secundum type ASD (aged mean 44.7 ± 8.2 years) were studied. The control group consisted of 25 healthy subjects at the mean age of 45.6 ± 6.1 years. Echocardiography and CPST were performed and BNP levels measured in all subjects. Oxygen uptake (VO2 max) was lower in ASD patients than in controls (22.1 ± 5.6 vs. 30.0 ± 6.8 ml/kg/min, p = 0.00001); the VE/VO2 slope was elevated in ASD patients compared with healthy subjects (31.3 ± 6.6 vs. 26.9 ± 3.3, p = 0.001), and exceeded 34 in 5 patients. VO2 max showed a negative correlation with the pulmonary to systemic flow ratio Qp:Qs (r = –0.46, p = 0.004), and a positive correlation was found between the VE/VO2 slope and Qp:Qs (r = 0.32, p = 0.05). BNP levels were higher in the ASD group than in the controls (60.6 ± 49.9 vs. 32.6 ± 24.5 pg/ml, p = 0.02). BNP correlated positively with RV diameter and Qp:Qs (r = 0.38 and 0.39 respectively, p = 0.03) and negatively with maximum VO2 (r = –0.5, p = 0.004) and VO2% (r = –0.32, p = 0.07). Conclusions: Although most adult patients with ASD perceive their exercise capacity as satisfactory, objective assessment reveals that in fact it is significantly decreased. BNP levels are increased comparing to healthy individuals. Decreased exercise capacity and increased BNP levels seem to result from right ventricular volume overload.


Platelets | 2015

Comparison of the antiplatelet effect of two clopidogrel bisulfate formulations: Plavix and generic-Egitromb

Anna Komosa; Jolanta M. Siller-Matula; J. Kowal; Maciej Lesiak; Andrzej Siniawski; M. Mączyński; Michał Michalak; Tatiana Mularek-Kubzdela; Stefan Grajek

Abstract Due to expansion of the pharmaceutical market it seems necessary to prove the efficacy of the generic drugs. The aim of this study is to compare the effects of two clopidogrel formulations: brand-name-Plavix and generic drug – Egitromb. This is a prospective, randomized study comparing two groups of patients treated with two clopidogrel: brand-name Plavix and generic drug– Egitromb. The 53 consecutive patients with stable coronary artery disease qualifying for coronary angiography and PCI were enrolled in this trial. They were randomized into two groups. In the group A (n = 28) patients received Egitromb 300 mg at admission followed by 8 days of 75 mg Egitromb daily. In the group B (n = 25) patients received Plavix 300 mg on the admission followed by 8 days of 75 mg Plavix maintenance therapy. Blood samples for multiple electrode aggregometry testing were drawn at baseline, 5 hours and 8 days after taking the loading dose. Median values of platelet aggregation inhibition did not differ between the Plavix and Egitromb groups when assessed at baseline: 239AU/min (IQR:329) vs. 209 (IQR:406; p = 0.894), 5 hours after loading: 183 AU/min (IQR:107) vs. 165 (IQR:171; p = 0.831) or at day 8: 174 AU/min (IQR:133) vs. 211 (IQR:133; p = 0.332. The study showed no difference in the therapeutic effect of two clopidogrel formulations (Egitromb and Plavix).


Eurointervention | 2016

Percutaneous coronary intervention for chronic total occlusion of the coronary artery with the implantation of bioresorbable everolimus-eluting scaffolds. Poznan CTO-Absorb Pilot Registry.

Maciej Lesiak; Magdalena Łanocha; Aleksander Araszkiewicz; Andrzej Siniawski; Marek Grygier; Małgorzata Pyda; Anna Olasińska-Wiśniewska; Sylwia Iwanczyk; Włodzimierz Skorupski; Przemysław Mitkowski; Lesiak M; Stefan Grajek

AIMS Data concerning the use of bioresorbable vascular scaffolds (BVS) for chronic total occlusion (CTO) lesions are limited. The aim of this study was to evaluate the early and midterm clinical outcomes of CTO stenting with BVS. METHODS AND RESULTS Forty consecutive patients (male 78%, mean age 59.9±8.3 years, diabetics 30%) with CTO treated with BVS were enrolled. Patients with a reference vessel diameter >4 mm, metallic stents, excessive calcium and tortuosity were excluded. Mean J-CTO score was 1.6. A total of 63 BVS were implanted with an average number of 1.6 per patient, and an average scaffold length of 42.4±21.5 mm. Procedural success was achieved in all patients with no device-related complications. At follow-up (median time 556 days), there were no deaths, one patient experienced subacute and late scaffold thrombosis (ST), and another one developed symptomatic in-scaffold focal restenosis treated with repeat PCI. At control angiography, performed at a median time of 329 days in 27 patients (68%), no more restenosis or vessel reocclusion was found. CONCLUSIONS CTO stenting with BVS is feasible with good acute performance, and good early and midterm clinical outcomes.


Journal of Cardiovascular Magnetic Resonance | 2013

Comparison of diffusion-weighted with T2-weighted imaging for detection of edema in acute myocardial infarction

Anna Kociemba; Małgorzta Pyda; Katarzyna Katulska; Magdalena Łanocha; Andrzej Siniawski; Magdalena Janus; Stefan Grajek

BackgroundRecent studies, performed with the use of a commercially available diffusion weighted imaging (DWI) sequence, showed that they are sensitive to the increase of water content in the myocardium and may be used as an alternative to the standard T2-weighted sequences. The aim of this study was to compare two methods of myocardial edema imaging: DWI and T2-TIRM.MethodsThe study included 91 acute and post STEMI patients. We applied a qualitative and quantitative image analysis. The qualitative analysis consisted of evaluation of the quality of blood suppression, presence of artifacts and occurrence of high signal (edema) areas. On the basis of edema detection in AMI and control (post STEMI) group, the sensitivity and specificity of TIRM and DWI were determined. Two contrast to noise ratios (CNR) were calculated: CNR1 - the contrast between edema and healthy myocardium and CNR2 - the contrast between edema and intraventricular blood pool. The area of edema was measured for both TIRM and DWI sequences and compared with the infarct size in LGE images.ResultsEdema occurred more frequently in the DWI sequence. A major difference was observed in the inferior wall, where an edema-high signal was observed in 46% in T2-TIRM, whereas in the DWI sequence in 85%. An analysis of the image quality parameters showed that the use of DWI sequence allows complete blood signal suppression in the left ventricular cavity and reduces the occurrence of motion artifacts. However, it is connected with a higher incidence of magnetic susceptibility artifacts and image distortion. An analysis of the CNRs showed that CNR1 in T2-TIRM sequence depends on the infarct location and has the lowest value for the inferior wall. The area of edema measured on DWI images was significantly larger than in T2-TIRM.ConclusionsDWI is a new technique for edema detection in patients with acute myocardial infarction which may be recommended for the diagnosis of acute injuries, especially in patients with slow-flow artifacts in TIRM images.


Advances in Interventional Cardiology | 2014

Significance of antiplatelet therapy in emergency myocardial infarction treatment

Anna Komosa; Maciej Lesiak; Andrzej Siniawski; Tatiana Mularek-Kubzdela; Stefan Grajek

Antiplatelet drugs play a crucial role in the treatment of patients with myocardial infarction, particularly in association with percutaneous coronary intervention. Their main advantage is the reduction of adverse ischemic incidents and the major disadvantage is the increase in the frequency of hemorrhages. Thus, the choice of appropriate drug depends on the right risk assessment of the development of these complications in individual patients. The aim of this article is to provide an update of antiplatelet therapy in emergency myocardial infarction treatment. Currently, the most important role in the process of platelet inhibition is played by ADP P2Y12 blockers: clopidogrel, prasugrel and ticagrelor. Clopidogrel and prasugrel belong to thienopyridines, and ticagrelor, a drug of irreversible action, is an analogue of adenosine triphosphate. By 2011 clopidogrel, alongside aspirin, had the highest recommendations of world cardiology associations for acute coronary syndrome treatment. The position on clopidogrel was changed following the publication of European Society of Cardiology guidelines for STEMI in 2012 which advocate the administration of acetylsalicylic acid (ASA) and ADP receptor blocker (in combination with ASA). It needs to be stressed that prasugrel and ticagrelor received class IB recommendation, while clopidogrel received only IC. However, the most recent studies aimed at introducing a new generation of antiplatelet drugs of high efficacy in prevention of ischemic incidents and of reversible action: cangrelor and elinogrel, which raise hopes for better prognosis for myocardial infarction patients.


Journal of Cardiovascular Magnetic Resonance | 2015

Influence of inflammatory response on infarct size and microvascular obstruction estimated by cardiac magnetic resonance in patients with ST-elevation myocardial infarction

Justyna Rajewska-Tabor; Magorzata Pyda; Anna Kociemba; Magdalena Janus; Magdalena Lanocha; Andrzej Siniawski

Background The inflammatory response during ST-segment elevation myocardial infarction (STEMI) has been shown to influence the clinical outcome. Moreover, infarct size (IS) and microvascular obstruction (MVO) predict major adverse events in patients with STEMI. The aim of the study was to compare the inflammatory response measured by C-reactive protein (CRP) serum concentration and the number of white blood cells (WBC) with the infarct size and MVO estimated by CMR. Methods We examined 85 patients (mean age 59±11 years; 59 males and 26 females) with acute STEMI. CRP and white blood cells were measured at the admission to the hospital. CMR examinations were performed on a 1.5 T scanner (Siemens, Avanto) using an eight-channel phased-array coil combined with 4-6 elements of spinal coil within 3 days after STEMI. Cine imaging with steady-state free precession and late gadolinium enhancement (LGE) were performed in the long axis and the contiguous short axis slices to evaluate myocardial function, IS and MVO. Infarct size was defined as an area greater than 50% of the maximal signal intensity within LGE (FWMH - full-width half maximum). MVO was diagnosed as an area of contrast hypoenhancement within the infarct zone and was included in the assessment of IS. IS and MVO were determined by planimetry and a summation of discs method. Results


Journal of Cardiovascular Magnetic Resonance | 2011

Detection of myocardial oedema with the use of diffusion-weighted imaging in acute myocardial infarction

Anna Kociemba; Magdalena Lanocha; Katarzyna Katulska; Andrzej Siniawski; Magdalena Janus; Stefan Grajek; Małgorzata Pyda

MR diffusion-weighted imaging is an important application for oedema detection in various tissues. Evaluation of the area at risk in reperfused acute myocardial infarction (AMI) is currently performed with STIR T2-weighted and LGE sequences.


Frontiers in Endocrinology | 2018

The Usefulness of Magnetic Resonance Imaging of the Cardiovascular System in the Diagnostic Work-Up of Patients With Turner Syndrome

Monika Obara-Moszynska; Justyna Rajewska-Tabor; Szymon Rozmiarek; Katarzyna Karmelita-Katulska; Anna Kociemba; Barbara Rabska-Pietrzak; Magdalena Janus; Andrzej Siniawski; Bartlomiej Mrozinski; Agnieszka Graczyk-Szuster; Marek Niedziela; Małgorzata Pyda

Cardiovascular defects occur in 50% of patients with Turner syndrome (TS). The aim of the study was to estimate the usefulness of cardiac magnetic resonance imaging (CMR) and magnetic resonance angiography (angio-MR) as diagnostics in children and adolescents with TS. Forty-one females with TS, aged 13.9 ± 2.2 years, were studied. CMR was performed in 39 patients and angio-MR in 36. Echocardiography was performed in all patients. The most frequent anomalies diagnosed on CMR and angio-MR were as follows: elongation of the ascending aorta (AA) and aortic arch, present in 16 patients (45.7%), a bicuspid aortic valve (BAV), present in 16 patients (41.0%), and partial anomalous pulmonary venous return (PAPVR), present in six patients (17.1%). Aortic dilatation (Z-score > 2) was mostly seen at the sinotubular junction (STJ) (15 patients; 42.8%), the AA (15 patients; 42.8%), the thoracoabdominal aorta at the level of a diaphragm (15 patients; 42.8%), and the transverse segment (14 patients; 40.0%). An aortic size index (ASI) above 2.0 cm/m2 was present in six patients (17.1%) and above 2.5 cm/m2 in three patients (8.6%). The left ventricular end-diastolic volume (EDV), end-systolic volume (ESV), and stroke volume (SV) were diminished (Z-score < −2) in 10 (25.6%), 9 (23.1%), and 8 patients (20.5%), respectively. A webbed neck was correlated with the presence of vascular anomalies (p = 0.006). The age and body mass index (BMI) were correlated with the diameter of the aorta. Patients with BAV had a greater aortic diameter at the ascending aorta (AA) segment (p = 0.026) than other patients. ASI was correlated with aortic diameter and descending aortic diameter (AD/DD) ratio (p = 0.002; r = 0.49). There was a significant correlation between the right ventricular (p = 0.002, r = 0.46) and aortic diameters at the STJ segment (p = 0.0047, r = 0.48), as measured by echocardiography and CMR. Magnetic resonance can identify cardiovascular anomalies, dilatation of the aorta, pericardial fluid, and functional impairment of the ventricles not detected by echocardiography. BMI, age, BAV, and elongation of the AA influence aortic dilatation. The ASI and AD/DD ratio are important markers of aortic dilatation. The performed diagnostics did not indicate a negative influence of GH treatment on the cardiovascular system.


Advances in Interventional Cardiology | 2017

Right heart catheterization procedures in patients with suspicion of pulmonary hypertension – experiences of a tertiary center

Maciej Grymuza; Katarzyna Małaczyńska-Rajpold; Stanisław Jankiewicz; Andrzej Siniawski; Marek Grygier; Przemysław Mitkowski; Marta Kałużna-Oleksy; Maciej Lesiak; Tatiana Mularek-Kubzdela; Aleksander Araszkiewicz

Introduction Right heart catheterization (RHC) is an invasive procedure providing direct and accurate measurements of hemodynamics of the cardiovascular system. Acute pulmonary vasoreactivity testing (APVT) following basal RHC in some patients is an established tool evaluating the reversibility of hypertension in the pulmonary vasculature. Aim We sought to assess the most common indications, vascular approaches and complications during RHC in a single high-volume center. Material and methods A total of 534 RHC procedures in 348 patients (64% male) were performed. The prospective registry was carried out for 28 months. Collected data included indications for RHC, vascular approaches, hemodynamic and clinical data, complications and response of pulmonary vessels in APVT. Results In 401 (75%) procedures pulmonary hypertension (mean pulmonary artery pressure (mPAP) ≥ 25 mm Hg) was confirmed. Left heart failure was the most common indication (55.8%), mainly ischemic (26%) or dilated cardiomyopathy (19.9%). Other indications included a suspicion of arterial (21.7%), or chronic thromboembolic pulmonary hypertension (14.6%). The right internal jugular vein approach was used in 89.1% of procedures. Acute pulmonary vasoreactivity testing was performed in 143 patients, and it was positive in 67 (46.9%) cases. Complications occurred in 21 (3.9%) procedures and included pulmonary edema (0.2%), pneumothorax (0.2%) and puncture of the artery followed by the insertion of a vascular sheath (0.4%), atrial arrhythmia (0.2%), superior vena cava dissection (0.2%), incidental artery puncture (1.1%) and local hematoma (2.2%). Conclusions The most frequent indication for RHC was left heart failure, and the most common approach was the right internal jugular vein. RHC is safe procedure with a low rate of major complications.


Journal of Cardiovascular Magnetic Resonance | 2015

Detection of myocardial edema with diffusion weighted imaging in patients with acute myocarditis

Anna Kociemba; Justyna Rajewska-Tabor; Magdalena Lanocha; Magdalena Janus; Andrzej Siniawski; Katarzyna Karmelita-Katulska; Magorzata Pyda

Methods We have analyzed 26 consecutive patients: 22 male, average age: 27 years (range 13-43) with clinical diagnosis of acute myocarditis. The CMR examinations were performed on a 1,5 T scanner using an eight-channel phasedarray coil combined with 4-6 elements of spinal coil. All patients underwent assessment of myocardial oedema: T2weighted triple inversion recovery (STIR), T1-weighted turbo spin echo pre and post contrast, function (cine Steady State Free Precession) and scar (Late Gadolinium Enhancement). Additionally DWI EPI sequence with b = 50 sec/mm was acquired before contrast administration. The sequence parameters were as follows: slice thickness 10 mm, repetition time (depending on patient breath cycle) 3-4 s, echo time 78 ms, bandwidth 1,736 Hz/Px. The DWI sequence was ECG-gated and synchronized to the respiratory cycle using PACE technique. For all patients T1 and T2 ratio were calculated and presence of LGE areas were reported. For STIR and DWI contrast between healthy myocardium and edema was calculated as a difference between edematous and normal myocardial muscle divided by standard deviation of image noise. Results We managed to acquired good quality DWI images in all 26 patients, average acquisition time was 120s per slice, distortion artifacts occurred in 5 patients but did not impaired diagnostic value of analyzed images. Increased signal intensity in DWI images occurred in all patients in the area of LGE enhancement and were consistent with areas of increased signal in STIR. All patients met at least two out of three criteria for inflammatory activity and injury. T2 ratio was increased (≥ 2) in 24 patients, T1 ratio (≥ 4) in 23 cases, all patients had focal non ischemic enhancement in LGE. CNR was higher in DWI than in STIR: 23,8 vs. 17,6 respectively.

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Stefan Grajek

Poznan University of Medical Sciences

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Maciej Lesiak

Poznan University of Medical Sciences

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Małgorzata Pyda

Poznan University of Medical Sciences

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Adrian Gwizdała

Poznan University of Medical Sciences

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Anna Kociemba

Poznan University of Medical Sciences

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Magdalena Janus

Poznan University of Medical Sciences

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Magdalena Lanocha

Poznan University of Medical Sciences

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Marek Grygier

Poznan University of Medical Sciences

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Przemysław Mitkowski

Poznan University of Medical Sciences

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