PubMed Health⌕ Search

Biomedical subjects

Bilgin Timuralp

Publications and source records attributed to Bilgin Timuralp.

At least 19 recordsLinked to original sources
PubMed2007

The effect of successful electrical cardioversion on left ventricular diastolic function in patients with persistent atrial fibrillation: a tissue Doppler study.

BACKGROUND: Changes in mitral inflow and pulmonary venous flow after electrical cardioversion (ECV) in patients with persistent atrial fibrillation (AF) were showed in many former studies. In our study we investigated the effects of ECV on diastolic parameters by using tissue Doppler imaging (TDI) in patients with persistent AF. METHODS: Forty-one (24 women) consecutive patients underwent successful elective ECV for nonvalvular persistent AF, and maintained sinus rhythm for 1 month were enrolled to the study. Transthoracic echocardiography was applied to all patients before, 24 hours after and 1 month after ECV. Mitral annular TDI parameters were also measured with mitral inflow, pulmonary venous flow, and other standard echocardiographic measurements. RESULTS: No differences in peak myocardial early velocity (Em), deceleration time of Em, and myocardial isovolumic relaxation time measured from mitral lateral annulus before, 24 hours after, and one month after ECV were found. Peak myocardial late velocity measured 24 hours after ECV increased significantly at the end of 1 month. CONCLUSION: There were not any changes in LV diastolic function except restoration of atrial mechanical contraction following ECV in patients with persistent AF.

Aged↗
PubMed2006

Atrial fibrillation after percutaneous coronary intervention: predictive importance of clinical, angiographic features and P-wave dispersion.

Atrial fibrillation (AF) may occur during or after percutaneous coronary interventions (PCI). The purpose of the study was to determine the clinical, angiographic and electrophysiological predictors of AF after PCI. 225 patients undergoing PCI (mean age of 65 +/- 11 years) who had sinus rhythm (SR) before balloon inflation were taken to study. Of these 22 developed AF in catheterization laboratory after balloon inflation or in 24 h following PCI (AF group), 203 did not (SR group). The patients in AF group were older (67 +/- 9 vs. 63 +/- 8 years, p < 0.05) and their ventricular ejection fraction was lower than SR group (56 +/- 5 vs. 45 +/- 7%, p < 0.05). The P-wave dispersion was significantly higher in AF group than SR group (53 +/- 8 vs. 29 +/- 10 ms, p < 0.001). For the patients with ST elevation myocardial infarction, the time from the onset of symptoms to balloon inflation was 3.7 +/- 1.7 h in SR group. It was longer in AF group (4.1 +/- 1.8 h, p < 0.05). TIMI perfusion grades 2 and 3 were achieved in 23 of 27 patients in SR group, and 5 of 8 patients in AF group. Multivessel disease was documented in 93 of the patients in SR group, and 12 in AF group. Clinical reperfusion was thought to be established in 20 in SR group, and 4 in AF group. In conclusion, our results show the importance of clinical factors, angiographic results and P-wave analysis in prediction of AF following PCI.

Aged↗
PubMed2006

Importance of initiation pattern of polymorphic ventricular tachycardia in patients with implantable cardioverter defibrillators.

BACKGROUND: Stored intracardiac electrograms (ICEGs) are helpful in understanding the initiation mechanisms of sustained ventricular arrhythmias and in determining the appropriateness of the therapy delivered by implantable cardioverter defibrillators (ICDs). AIM: We investigated the initiation pattern of sustained polymorphic ventricular tachycardia (PVT) and the features of the therapy delivered by ICDs. METHODS: Sixty-six patients (mean age of 67 +/- 8 years) with 97 stored ICEGs showing PVT were evaluated. Cardiovascular diagnosis included coronary artery disease in 72.7% of the patients. The average left ventricular ejection fraction was 33+/-6%. RESULTS: Nonsudden onset episodes were more common than sudden onset episodes (63 episodes, 65% vs 34 episodes, 35%, P < 0.001). More PVT episodes were required multiple shock delivery if they had nonsudden onset initiation (28.6% vs 23.6%, P < 0.01). The mean shock energy delivered for arrhythmia termination was higher in PVT with nonsudden onset (20 +/- 4 vs 14 +/- 5 J, P < 0.01). CONCLUSIONS: The stored ICEGs demonstrate that PVT is most often preceded by ventricular ectopy. To be reverted, nonsudden onset episodes require higher levels of shock energy and more frequently multiple shock achievements than sudden onset episodes.

Aged↗
PubMed2005

Visualization of the site of the onset of ventricular depolarization by acceleration mode Tissue Doppler imaging technique.

Tissue Doppler imaging (TDI) is a relatively new echocardiographic technique that shows regional myocardial wall velocities. The aim of this study was to evaluate the potential value of acceleration mode TDI technique for the visualization of the origin of ventricular activation site using the model of right ventricular pacing. Twenty-seven patients with implanted permanent pacemakers were studied by acceleration mode TDI, 4 of these patients were pacemaker dependent. Parasternal and apical chamber views were recorded on video tape by using acceleration mode TDI technique during sinus rhythm with preserved atrioventricular conduction in 23 subjects who were not pacemaker-dependent, and also during right ventricular apical pacing in VVI mode in 27 subjects in whom pacing lower rate was increased if necessary. Fifty images recorded during sinus and pacing rhythm in cineloop were examined by two independent observers who were unaware of the rhythm patterns and by the same observer on two different occasions for localizing the site of onset of ventricular acceleration. The origin of ventricular activation during sinus rhythm started at basal septal part of the ventricle and during pacing started at apical part of the ventricle was considered as correct localizations. The origin of ventricular depolarization was correctly localized for 46 of 50 images (92%) and 44 of 50 images (88%) by the first and the second observers, respectively. Concordant results between observers appeared in 48 of 50 (96%) of images. The diagnostic accuracy of the concordant results was 44 of 48 (91.6%) images. The kappa for interobserver variability was 0.77 (p<0.001), and for intraobserver variability was 0.64 (p<0.001) and 0.63 (p<0.001) for the first and the second observers, respectively. These results suggest that acceleration mode TDI can be used to detect the initial ventricular excited position and seems to have a potential value for localizing of the origin of normal or abnormal myocardial depolarization.

Adult↗
PubMed2005

Detection of hibernate myocardium by 99mTc sestamibi gated SPECT during low-dose dobutamine infusion plus nitrate in patients with first acute myocardial infarction.

AIM: To investigate the role of Tc-MIBI gated SPECT imaging following the administration of low-dose dobutamine plus nitrate (LDD+nitrate) in the assessment of left ventricular function and the perfusion of hibernate myocardial tissue. METHODS: The study group comprised 29 patients diagnosed as having acute myocardial infarction. In the first month post-infarction, Tc-MIBI gated SPECT imaging was performed in all patients at rest-dobutamine stress and LDD+nitrate. Ejection fraction, end diastolic volume (EDV), end systolic volume (ESV), stroke volume, volume, extent score, and reversibility score values were calculated. RESULTS: The findings of Tc-MIBI gated SPECT imaging following the administration of LDD+nitrate and the rest Tc-MIBI gated SPECT findings revealed that while the levels of ejection fraction (P=0.004) and reversibility score (P=0.000) increased significantly, there was a significant decrease in EDV (P=0.001), ESV (P=0.001), volume (P=0.017), stroke volume (P=0.257) and extent score (P=0.039) values. CONCLUSION: The use of Tc-MIBI gated SPECT concomitantly with the administration of LDD+nitrate is useful in the determination of myocardial hibernation in patients with left ventricular failure following acute myocardial infarction.

Adult↗
PubMed2005

Long-term effects of antilipidaemic therapy on left ventricular function in patients with dyslipidaemia: multigated radionuclide ventriculography study.

AIM: It has been reported that dyslipidaemia impairs left ventricular systolic (LVs) and diastolic (LVd) functions, irrespective of atherogenic effects, in the setting of coronary artery disease. The aim of the present study was to evaluate the effects of anti-lipidaemic therapy on LVs and LVd functions by means of multigated radionuclide ventriculography (RNV) in subjects with signs of dyslipidaemia and with preserved left ventricular function. METHODS: Eighteen patients with dyslipidaemia (eight men, 10 women, mean age 50+/-10 years) were included in the study. While the clinical examination and treadmill exercise test results were normal in all patients, low-density lipoprotein levels exceeded 160 mg . dl. Patients with medical conditions including coronary artery disease, hypertension, diabetes, cardiomyopathy and valvular heart disease which would influence left ventricular function were excluded from the study. RNV was performed in all subjects, taking into account the best septal position to differentiate the left ventricle from the right ventricle. The following parameters were calculated: ejection fraction, peak ejection rate (PER), time to peak ejection (TPER), a ejection rate (aER), a ejection fraction (aEF), Peak filling rate (PFR), time to peak filling rate (TPFR), a filling rate (aFR), a filling fraction (aFF). RESULTS: The low-density lipoprotein value decreased and the high-density lipoprotein value increased after statin therapy (P<0.001 and P<0.003, respectively). PER, aER and aFF significantly increased and TPER decreased as a consequence of statin therapy (respectively, P<0.05, P<0.05, P<0.05 P<0.05). CONCLUSION: Anti-lipidaemic therapy is effective in dyslipidaemic patients. RNV is a useful and non-invasive method for monitoring changes in ventricular function following anti-lipidaemic treatment strategies.

Dyslipidemias↗
PubMed2005

Regional distribution and extent of perfusion abnormalities, and the lung to heart uptake ratios during exercise thallium-201 SPECT imaging in patients with cardiac syndrome X.

BACKGROUND: Cardiac syndrome X is defined as angina-like chest pain with transient ischemic ST-segment changes during exercise and angiographically normal epicardial coronary arteries. Studies with myocardial perfusion imaging in this syndrome have indicated that some patients, but not all, have an abnormality on perfusion scan. However, the impact of these perfusion abnormalities on pulmonary thallium uptake is not clear in this group of patients. OBJECTIVE: To evaluate the regional distribution and extent of perfusion abnormalities, and the lung to heart (L:H) uptake ratios using exercise thallium-201 single-photon emission computed tomography (TI-201 SPECT) in patients with cardiac syndrome X. METHODS: The study group consisted of 31 selected cardiac syndrome X patients with regional perfusion abnormalities during exercise TI-201 SPECT imaging. A control group included 26 healthy subjects with normal coronary angiograms, exercise testing and exercise TI-201 SPECT imaging. Exercise TI-201 SPECT results were analyzed with further estimation of the L:H ratios, number and localization of regional perfusion defects, and their mean extent scores expressed in pixels and in per cent of the left ventricular wall. Twenty-two patients with known coronary artery disease were also included in the analysis of the L:H ratios. RESULTS: Multiple perfusion defects were detected in 13 (42%) patients and perfusion defects of single localization were detected 18 (58%) patients. All patients had reversible perfusion abnormalities: 21 (67.7%) had anterior, 14 (45.2%) had inferior and 12 (38.7%) had lateral localization of perfusion defects. The analysis of the extent of the perfusion defects revealed that the mean scores of the extent of the single regional defects were 38.61+/-43.8 pixels and those of multiregional defects were 106.1+/-55.2 pixels, which corresponded to 6.05+/-1.8% and 16.6+/-5.4% of the left ventricular wall defects, respectively. Patients with cardiac syndrome X had a significantly higher L:H ratio during exercise than the healthy subjects (0.46+/-0.02 versus 0.34+/-0.03, P<0.01). In addition, L:H ratios were found to be higher in patients with multiple perfusion defects (0.50+/-0.02) than in patients who had only anterior (0.45+/-0.08) or inferior (0.43+/-0.02) perfusion defects (P<0.05 for both). There were no statistically significant differences in the rest L:H ratios between the study and control groups. Also, no significant differences were observed in exercise L:H ratios between the cardiac syndrome X patients and the patients with coronary artery disease (0.46+/-0.02 versus 0.49+/-0.03, P>0.05). CONCLUSIONS: The results suggest that multiple perfusion defects in multiple vascular regions are relatively common in cardiac syndrome X patients, with the majority of these patients having at least one abnormal perfusion bed. Patients with this syndrome who have perfusion abnormalities also had significantly higher L:H ratios during exercise than did the control patients. Increased exercise L:H ratios were more prominent in patients with multiple perfusion defects.

Adult↗
PubMed2005

Transesophageal echocardiographic diagnosis of ventricular noncompaction associated with an atrial septal aneurysm in a patient with dilated cardiomyopathy of unknown etiology.

The present report discusses a case of noncompaction of the ventricular myocardium in a 51-year-old woman with dilated cardiomyopathy of unknown etiology. Multiple transthoracic echocardiography examinations had failed to show myocardial noncompaction, but subsequently performed transesophageal echocardiography clearly demonstrated the characteristic findings of this unusual disease. Also, an atrial septal aneurysm was identified by transesophageal echocardiography. Patients with cardiomyopathy of unknown origin should be investigated to define the presence or absence of myocardial noncompaction, even if transthoracic echocardiography fails to show anatomical features of this disease. The present case is the first reported case of ventricular noncompaction associated with an atrial septal aneurysm as a congenital anomaly.

Cardiomyopathy, Dilated↗
PubMed2003

Initiation of monomorphic ventricular tachycardia: electrophysiological, clinical features, and drug therapy in patients with implantable defibrillators.

At least 2 distinct patterns of sustained monomorphic ventricular tachycardia (MVT) have been ascribed during analysis of stored intracardiac electrograms retrieved from implantable cardioverter defibrillators and Holter recordings in patients with ventricular arrhythmia. We aimed to investigate the electrophysiological features of MVT with different initiation patterns in patients with implantable cardioverter defibrillators and to assess whether there is a relationship of the initiation patterns of sustained MVT with clinical characteristics and efficacy of antiarrhythmic therapy. Seventy-four stored intracardiac electrograms in 21 patients (mean age of 68.2 +/- 4.2 years) with MVT were evaluated. Cardiovascular diagnosis included coronary artery disease in 85.7% of the patients. All MVT episodes were classified as those initiating with ventricular premature beats (nonsudden onset MVT) and those without ventricular ectopy preceding tachycardia (sudden onset MVT). There was significant difference in left ventricular ejection fraction between MVTs with different initiation pattern, being the lower in those with nonsudden onset (33.6% +/- 38.4% vs. 38.4 +/- 7.0%, P <.04). Ventricular tachycardia cycle length was shorter in group of MVT with nonsudden onset as compared with sudden onset (338.5% +/- 48.1% vs. 376.8% +/- 57.0%, P <.02). Tachycardia with sudden onset was associated with shorter preceding RR interval than tachycardia with nonsudden onset (821.8 +/- 136.2% vs. 748.7 +/- 107.7%, P <.01). There were no significant differences in the type of antiarrhythmic drug therapy used between groups (P >.05). Monomorphic ventricular tachycardias with nonsudden onset occurred more frequently than with sudden onset, without precipitating RR cycles shortening, are faster in rate, associating with lower ejection fraction. Monomorphic ventricular tachycardias with sudden onset are characterized by preceding shortening of RR intervals, slower cycle length, and less worsening of ejection fraction.

Aged↗