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Dive into the research topics where Muharrem Güldal is active.

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Featured researches published by Muharrem Güldal.


Pacing and Clinical Electrophysiology | 1987

Permanent Pacemaker Implantation in a Pregnant Woman with the Guidance of ECG and Two-Dimensional Echocardiography

Muharrem Güldal; Celal Kervancioğlu; Derviş Oral; Türkan Gürel; Çetin Erol; Ahmet Sonel

A 30‐year‐old pregnant woman was admitted to the Cardiology Research Center with syncope, dizziness, and fatigue on exertion. On ECG complete atrioventricular block was diagnosed. Permanent pacemaker implantation was performed with the guidance of ECG and two‐dimensional echocardiography and without the use of fluoroscopy.


Canadian Journal of Cardiology | 2007

Torsade de pointes associated with moxifloxacin: A rare but potentially fatal adverse event

Timucin Altin; Ozgur Ulas Ozcan; Sibel Turhan; Aydan Ongun Ozdemir; Ömer Akyürek; Remzi Karaoguz; Muharrem Güldal

Torsade de pointes occuring due to a long QT interval is a rare but potentially fatal arrhythmia. Acquired long QT develops most commonly because of drugs that prolong ventricular repolarization. It has been reported that fluoroquinolone antimicrobials prolong the corrected QT interval but rarely cause torsade de pointes. A patient with torsade de pointes risk factors (female sex, advanced age, extreme bradycardia and renal failure) who developed the condition on the fourth day of 400 mg/day of oral moxifloxacin treatment is presented. After the moxifloxacin was stopped, the corrected QT interval normalized and a permanent cardiac pacemaker was implanted. During 11 months of follow-up, arrhythmia did not recur.


American Journal of Cardiology | 1999

Value of ST-segment depression during paroxysmal supraventricular tachycardia in the diagnosis of coronary artery disease.

Sadi Gulec; Fatih Ertaþ; Remzi Karaoŏuz; Muharrem Güldal; Ahmet Alpman; Derviþ Oral

We evaluated 39 patients >45 years old with paroxysmal supraventricular tachycardia (SVT), 21 of whom had ST-segment depression during SVT. Treadmill exercise testing, including thallium stress scintigraphy, was performed in all patients and coronary angiography in 21 patients with ST-segment depression. Based on the presence of abnormal findings on exercise electrocardiogram and/or thallium in 7 of 21 patients (33%) with ST-segment depression, with additional corroboration by angiographic data, we conclude that myocardial ischemia and coronary artery disease is one, but not the only, mechanism involved in the genesis of ST-segment depression during paroxysmal SVT.


International Journal of Cardiology | 2001

Heart rate variability in hypertrophic obstructive cardiomyopathy: association with functional classification and left ventricular outflow gradients.

Oben Döven; Tamer Sayin; Muharrem Güldal; Remzi Karaoguz; Derviş Oral

BACKGROUND The aim of this study was to investigate cardiac autonomic control in patients with hypertrophic obstructive cardiomyopathy (HOCM) and to assess the indexes of heart rate variability (HRV) in relation to the clinical and echocardiographic features. METHODS AND RESULTS Twenty-three patients (17 male, six female: mean age 43+/-11) with HOCM and 18 healthy volunteers were included. M-mode and two-dimensional echocardiography, pulsed and continuous-wave Doppler studies were obtained. All patients and volunteers underwent continuous 24-h ambulatory ECG monitoring. Time domain variables considered in this study were standard deviation of mean R-R intervals (SDNN), root mean-squared successive difference (RMSSD) and percentage of cycles differing from the preceding one by more than 50 ms (PNN 50%). Patients were compared to detect associations between indices of heart rate variability, left ventricular outflow tract obstruction and clinical status. Heart rate variability parameters were also correlated with the echocardiographic and clinical characteristics of the patients. Both New York Heart Association (NYHA) functional class I-II patients (group I) and NYHA III-IV patients (group II) had lower values of SDNN, RMSSD and PNN 50% when compared with the control group (P<0.001, P<0.05 and P<0.01, respectively, for group I and P<0.001, P<0.001 and P<0.001, respectively, for group II). Time domain heart rate variability parameters were found to be significantly correlated with the subaortic dynamic obstruction. CONCLUSION Heart rate variability is reduced in HOCM and well correlated with the degree of subaortic obstruction. Heart rate variability indices are also sensitive markers of the functional status.


International Journal of Cardiology | 1993

Cardioinhibitory response to carotid sinus massage in patients with coronary artery disease.

Ahmet Alpman; Derviş Oral; Muharrem Güldal; Çetin Erol; Kenan Ömürlü; Berkten Berkalp; Zehra Dagalp; Turhan Akyol

The relationship between cardioinhibitory response to the carotid sinus massage and the severity of coronary artery lesions and left ventricular impairment was investigated in 86 patients who underwent coronary angiography. The study group (Group 1) comprised 63 patients who had coronary lesions and the control group (Group 2) comprised 23 patients who had normal coronary arteries. There was no significant relationship between the severity of coronary artery lesions and the cardioinhibitory response to the carotid sinus massage in the study group. However, there was a positive correlation (r = 0.478, P < 0.01) between total left ventricular segment scores and the maximal change in RR interval (%) during the right carotid sinus massage in the study group. During the right carotid sinus massage, maximal change of RR interval (%) was significantly higher in patients who had segmental wall motion abnormalities than in patients who did not (83.0 +/- 72.4% vs. 32.9 +/- 42.5%, P < 0.01, respectively). In the patients who could have echocardiographic measurements there was negative correlation between fractional shortening value and maximal change of RR interval (%) (right massage; r = -0.482, P < 0.01, left massage; r = -0.334, P < 0.05). In conclusion, we found a significant relationship between the cardioinhibitory response to carotid sinus massage and the presence and severity of the segmental wall motion abnormalities and left ventricular impairment in patients with coronary artery disease.


Journal of Electrocardiology | 1995

Importance of notching and slurring of the resting QRS complex in the diagnosis of coronary artery disease

Ahmet Alpman; Muharrem Güldal; Berkten Berkalp; Erdem Diker; Çetin Erol; Derviş Oral

Data on the correlation of coronary artery disease (CAD) and electrocardiographic findings are, except for Q waves, still controversial. The purpose of this study was to determine whether QRS complex notching and slurring (N&S) is of significant value as a diagnostic discriminator in the detection of CAD. This study comprised 500 consecutive patients aged between 24 and 81 years (mean, 53.4 years) who underwent coronary angiography because of chest pain. Patients were evaluated for CAD, angiographic evidence of myocardial infarction (MI), N&S, and abnormal Q waves. Of these 500 patients, 418 had CAD, and 370 of these had significant (> or = 70%) coronary artery obstruction. The remaining 82 patients had normal coronary arteries. The data revealed that the distribution of N&S in the patients with or without CAD was similar in both the inferior and limb leads (P > .05). But the percentage of N&S in more than two contiguous limb leads was higher in the patients with CAD than in the patients without CAD. Notching and slurring in at least one limb lead was found to be of no value in the diagnosis of MI, of wall motion abnormalities, and of significant obstruction. Notching and slurring in the anterior leads is more sensitive but less specific than abnormal Q waves in the same leads in the detection of significant obstruction, anterior MI, and anterior wall motion abnormalities. Notching and slurring in the anterior leads has as much importance as abnormal anterior Q waves in the detection of angiographic evidence of anterior infarct, of anterior wall motion abnormalities, and of significant coronary artery obstruction.(ABSTRACT TRUNCATED AT 250 WORDS)


Pacing and Clinical Electrophysiology | 2007

Effect of transvenous cardiac resynchronization therapy device implantation on cardiac troponin I release

Timucin Altin; Ömer Akyürek; Kutay Vurgun; Osman Beton; Tamer Sayin; Mustafa Kilickap; Remzi Karaoguz; Muharrem Güldal; Çetin Erol

Background: Pacemaker and implantable cardioverter defibrillator (ICD) implantation increases cardiac troponin I (cTnI) levels which indicates myocardial injury. During implantation of a cardiac resynchronization therapy (CRT) device, balloon inflation for coronary sinus (CS) venogram, cannulation of CS side branch, and electrode advancement may interfere with CS drainage and, hence, may decrease the washout of toxic metabolites from the heart. Thus, CRT implantation may further increase cTnI levels. In this study, we investigated the effects of CRT implantation on cTnI release.


Annals of Noninvasive Electrocardiology | 2008

The impact of the distance between the atrial electrode and the atrial wall on atrial undersensing in patients with VDD pacemakers: long-term follow-up.

Timucin Altin; Muharrem Güldal; Basar Candemir; Cegerhun Polat; Aydan Ongun Ozdemir; Cansin Tulunay; Cagdas Ozdol; Ömer Akyürek; Remzi Karaoguz; Çetin Erol

Aim: Atrial undersensing (AUS) in single‐lead VDD pacemakers may be due to diminished P‐wave amplitude secondary to local inflammation beneath the electrodes closer to atrial wall. The aim of this study was to assess the potential effect of distance between atrial electrode and atrial wall on immediate and long‐term atrial sensing stability in VDD systems.


International Journal of Cardiology | 2000

Left atrial appendage function in patients with different pacing modes

Fatih Sinan Ertaş; Sadi Gulec; Irem Dincer; Çetin Erol; Eralp Tutar; Muharrem Güldal; Remzi Karaoguz; Derviş Oral

Many studies suggest that patients who receive a ventricular pacemaker have a higher incidence of systemic thromboembolism compared to patients receiving a physiological pacemaker. However, the exact mechanism regarding the etiology of thromboembolism remains unclear. We evaluated the left atrial appendage (LAA) functions, using multiplane transesophageal echocardiography (TEE), in patients with different pacing modes. In order to evaluate the ejection fraction (EF), peak emptying (V(E)) and filling (V(F)) flow velocities of the LAA by TEE, we studied 31 patients (mean age 63+/-18.5 years) who had been paced for 5.0+/-2.9 years. Patients with atrial fibrillation, left ventricular dysfunction and mitral valve disease were excluded. The pacing indications were complete atrioventricular block (AVB) in 19 patients (9 VVI, 10 VDD or DDD) and sick sinus syndrome (SSS) in 12 patients (5 VVI, 7 DDD). Mean EF, V(E) and V(F) of the LAA were significantly lower in all patients with ventricular pacing (25.5+/-15.6%, 30.4+/-15.6 cm/s and 29. 1+/-19.2 cm/s, respectively) compared to those with physiologic pacing (48.5+/-16.9%, 59.6+/-16.3 cm/s, 57.9+/-18.5 cm/s, respectively) (P<0.01 in all). When patients were further classified with respect to underlying heart disease whether they had SSS or AVB, all measurements of the LAA (EF, V(E) and V(F)) in both subgroup of patients with SSS and AVB were found significantly lower in those with ventricular pacing than in those with physiologic pacing (Tables 3 and 4). This decrease, especially in LAA flow, was much greater in those with SSS (Mean V(E) and V(F) <20 cm/s). In a patient paced with VVI for SSS, a thrombus was detected within the LAA cavity. In conclusion, these results suggest that the pacing modality appeared to influence the LAA functions in paced patients. Patients with asynchronous ventricular pacing modes had a significantly higher incidence of depressed LAA functions than did patients with physiological pacing, especially more marked in patients with sick sinus syndrome. This may be a factor responsible for increased risk of thrombus formation and thromboembolic events in this patient population.


Pacing and Clinical Electrophysiology | 1996

Undersensing of the Tiny QRS Complexes That Emerged After the Isolation of the Right Ventricle in a Patient with Ventricular Tachycardia

Muharrem Güldal; Remzi Karaoguz; Antonio Pacifico; Gerald M. Lawrie; Turhan Akyol

This article describes a patient who underwent right ventricular disconnection for medically refractory ventricular tachycardia associated with arrhythmogenic right ventricular dysplasia. After the operation there was no ventricular tachycardia recurrence. Two years after the operation, he received a permanent VVI pacemaker for the symptomatic second‐degree AV block. Sensing function of the pacemaker was normal for the normal QRS complexes, but the tiny QRS complexes that appeared after the arrhythmia surgery were not sensed by the pacemaker and therefore caused no problem.

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