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Yıldız, Ömer

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Ömer

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Yıldız

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Yıldız, Ömer

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2018 - 201952020 - 20212

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    How to safely implant a dual-chamber pacemaker for right ventricular outflow tract pacing in a patient with persistent left superior vena cava: a step by step guide
    (Taiwan Soc Cardiology, 2019) N/A; Yıldız, Ömer; Doctor; N/A; Koç University Hospital; N/A
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    AMPLATZER Muscular Ventricular Septal Occluder in transcatheter occlusion of the left main coronary artery in a patient with a huge aneurysm secondary to Kawasaki disease
    (Europa Edition, 2019) Çeliker, Alpay; N/A; Mutluer, Ferit Onur; Yıldız, Ömer; Doctor; Doctor; N/A; School of Medicine; Koç University Hospital; Koç University Hospital; N/A; N/A
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    QT dispersion in patients with chronic and advanced heart failure: is it only a methodological problem?
    (DNT Ortadoğu Yayıncılık, 2021) N/A; Yıldız, Ömer; Doctor; N/A; Koç University Hospital; N/A
    Aim: QT dispersion is a potential predictive marker for ventricular tachyarrhythmia events and sudden cardiac death (SCD). However, prior investigations on the prognostic value of QT dispersion in patients with chronic heart failure (CHF) have shown conflicting results. Therefore, the present study aims to assess the prognostic value of QT dispersion in patients with CHF. Material and Methods: A total of 66 patients with CHF (LVEF ≤35%, functional class NYHA II/III) were included in the study. Baseline ECG recording, Holter monitoring, equilibrium radionuclide ventriculography, and cardiopulmonary exercise test were carried out in all patients. Findings of the patients who experienced SCD group during the follow-up were compared with survivors. Results: Over 36.7 ± 11.7 months follow-up, 10 patients (7 of 10 with SCD) died, and 3 patients underwent cardiac transplantation. Mean heart rate (101 ± 23 vs. 81 ± 12bpm, p <0.006) and NHYA class (2.6 ± 0.5 vs. 2.0 ± 0.7; p <0.03) were significantly higher, and LVEF (16 ± 4 vs. 27 ± 8%, p <0.006) was significantly lower in the SCD group. No significant differences between the two groups were found for peak VO2 (13.6 ± 7.4 vs. 17.2 ± 5.8ml/kg/min, p =0.138), heart rate variability (88 ± 51 vs. 133 ± 59ms, p =0.059) and QT dispersion (88 ± 51 vs. 90 ± 35ms, p =0.089). Conclusions: Present findings indicate that in patients with chronic and advanced heart failure, both a decreased LVEF and increased heart rate but not QT dispersion provide predictive information on SCD. / Amaç: QT dispersiyonu ventriküler taşiaritmi ve ani kardiyak ölüm (AKÖ) olayları için potansiyel bir belirteçtir. Ancak, kronik kalp yetmezliği (KKY) olan hastalarda QT dispersiyonunun prognostik değeri üzerine yapılan önceki araştırmalar çelişkili sonuçlar göstermiştir. Bu çalışma, ileri evre KKY olan hastalarda QT dispersiyonunun prognostik değerini araştırmayı amaçlamaktadır. Gereç ve Yöntemler: Çalışmaya 66 ileri evre KKY olan hasta (sol ventriküler ejeksiyon fraksiyonu (SVEF) ≤%35, fonksiyonel sınıf NYHA II/III) dahil edildi. Tüm hastalarda başlangıçta EKG kaydı, holter monitörizasyonu, radyonüklid ventrikülografi ve kardiyopulmoner egzersiz testi yapıldı. Takip sırasında AKÖ grubu olan hastaların bulguları sağ kalanlarla karşılaştırıldı. Bulgular: Toplam 36,7 ± 11,7 ay üzerinde takipte, 10 hasta (7'sinde AKÖ) öldü ve 3 hastaya kalp nakli uygulandı. Ortalama kalp atış hızı (101 ± 23'e karşı 81 ± 12/dk., p <0,006) ve NHYA sınıfı (2,6 ± 0,5'e karşı 2,0 ± 0,7; p <0,03) anlamlı olarak daha yüksekti ve SVEF (16 ± 4'e karşı %27 ± 8, p <0,006) AKÖ grubunda anlamlı olarak daha düşüktü. Zirve VO2 (13,6 ± 7,4'e karşı 17,2 ± 5,8ml/kg/dk, p =0,138), kalp hızı değişkenliği (88 ± 51'e karşı 133 ± 59msn, p =0,059) ve QT dağılımı (88 ± 51'e karşı 90 ± 35msn, p =0,089) değerlerinde iki grup arasında anlamlı fark izlenmedi. Sonuç: Mevcut bulgular, ileri evre KKY olan hastalarda AKÖ riski açısından azalmış SVEF ve artmış kalp hızının istatiksel olarak anlamlı olduğunu, QT dispersiyonunun ise anlamsız öngörücü bilgi sağladığını göstermektedir.
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    The effect of cardiovascular risk factors and coronary atherosclerosis severity on long term graft patency rate in patients who underwent coronary artery bypass graft surgery
    (Sağlık Bilimleri Üniversitesi, 2021) Akbal, Özgür Yaşar; Kültürsay, Barkın; Keskin, Berhan; Çeneli, Doğancan; Tanyeri, Seda; Karagöz, Ali; Efe, Süleyman Çağan; Tokgöz, Hacer Ceren; Bayram, Zübeyde; Özdemir, Nihal; Kaymaz, Cihangir; Fındıkçıoğlu, Uğur; Sancar, Kadriye Memiç; Tayyareci, Yelda; Yazıcıoğlu, Nuran; Yurdakul, Selen; Çiftçi, Çavlan; Şahin, Bingül Dilekçi; N/A; Yıldız, Ömer; Doctor; N/A; Koç University Hospital; N/A
    Introduction: The postoperative success of coronary artery bypass grafting depends on graft patency rate. The atherosclerotic process goes on in native arteries and bypass grafts of patients who underwent coronary artery bypass graft surgery. In this study, we aimed to investigate the effect of preoperative cardiovascular risk factors and the extensity of atherosclerosis detected by coronary angiography on long-term graft survival after the operation. Patients and Methods: We included 974 patients (738 males, 236 females, mean age 57.9 ± 9.0 years) who underwent isolated coronary artery bypass graft surgery between the years 1990-2010 and coronary angiography due to various reasons during their follow-ups. The cardiovascular risk factors of the patients were detected and the extensity of coronary artery disease in the pre-operative coronary angiographies was determined by calculating Gensini Score Index. The effect of these results on graft patency was analyzed. Results: As a result of coronary angiography, overall graft patency rates were found to be 52.6%, 64.6%, and 38.4% in the 1st, 5th and 10th years, respectively. Arterial grafts showed better patency rates than venous grafts in both short-term (1st year) and long-term (5th and 10th years). Independent cardiovascular risk factors were age (beta: 0.006, p= 0.001), smoking (beta: 0.101, p= 0.003), and family history (beta: 0.063, p= 0.03) for all occluded grafts. Diabetes mellitus (beta: 0.03, p= 0.02) and Gensini Score Index (beta: 0.01, p= 0.03) were associated with occluded left internal mammary artery graft. Age (beta: 0.05, p= 0.002), smoking (beta: 0.073, p= 0.002), and Gensini Score Index (beta: 0.001, p= 0.002) were associated with occluded saphenous vein graft. Smoking (beta: 0.047, p= 0.001), family history (beta: 0.033, p= 0.013), and Gensini Score Index (beta: 0.001, p= 0.001) were associated with occluded right internal mammary artery graft. Conclusion: According to short and long-term results of a large group of patients, graft atherosclerosis was associated with cardiovascular risk factors, the extensity of coronary atherosclerosis, type and duration of graft. Today, primary and secondary cardiovascular risk factors should be improved to achieve higher longterm graft patency rates. / Giriş: Koroner arter baypas greft cerrahisi sonrası başarı, greft açıklığı ile doğru orantılıdır. Koroner arter baypas greft operasyonu geçiren hastalarda nativ arterler ve baypas greftlerinde aterosklerotik süreç devam eder. Bu çalışmanın amacı, koroner arter baypas greft cerrahisi öncesinde belirlenen kişiye ait kardiyovasküler risk faktörlerinin ve koroner anjiyografide saptanan ateroskleroz yaygınlığının operasyon sonrası uzun dönemde greft ömrüne etkisini araştırmaktır. Hastalar ve Yöntem: Çalışmaya 1990-2010 yılları arasında izole koroner arter baypas greft cerrahisi uygulanan ve takiplerinde çeşitli nedenlerle koroner anjiyografileri yapılan toplam 974 hasta (738’i erkek, 236’sı kadın, yaş ortalaması 57.9 ± 9.0 yıl) dahil edildi. Hastalara ait kardiyovasküler risk faktörleri saptandı ve operasyon öncesi koroner anjiyografilerdeki koroner arter hastalığının yaygınlığı Gensini skor indeksi hesaplanarak belirlendi. Tüm bunların uzun dönem greft açıklık oranına etkisi analiz edildi.Bulgular: Koroner anjiyografi sonucunda; tüm greftlerde açıklık oranı birinci yılda %52.6, beşinci yılda %64.6, 10. yılda %38.4 olarak bulunmuştur. Açıklık oranları hem erken (birinci yıl) hem de geç dönemlerde (5 ve 10. yıl) arteryel greftlerde, venöz greftlerden daha iyiydi. Kardiyovasküler risk faktörlerinden yaş (beta: 0.006, p= 0.001), sigara (beta: 0.101, p= 0.003) ve aile hikayesi (beta: 0.063, p= 0.03) tüm greftlerin tıkanıklığında bağımsız risk faktörü olarak bulunmuştur. Tıkalı sol internal mammary arter ile diabetes mellitus (beta: 0.03, p= 0.02) ve Gensini skor indeksi (beta: 0.01, p= 0.03); tıkalı safen ven greft ile yaş (beta: 0.05, p= 0.002), sigara (beta: 0.073, p= 0.002), Gensini skor indeksi (beta: 0.001, p= 0.002); tıkalı sağ internal mammary arter grefti ile sigara (beta: 0.047, p= 0.001), aile hikayesi (beta: 0.033, p= 0.013), Gensini skor indeksi (beta: 0.001, p= 0.001) ilişkili bulunmuştur. Sonuç: Geniş ölçekli bir hasta grubunda kısa ve uzun dönem sonuçların araştırıldığı bu çalışmada, greft aterosklerozu kardiyovasküler risk faktörleri, koroner aterosklerozun yaygınlığı, greft tipi ve greft süresi ile ilişkili bulunmuştur. Uzun dönem greft açıklık oranlarını artırmada günümüzde temel hedef, primer ve sekonder kardiyovasküler risk faktörlerinin iyileştirilmeye çalışılması olmalıdır.
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    Outcome of drug resistant severe atrial tachycardia during pregnancy treated with catheter ablation
    (Premchand Shantidevi Research Foundation, 2018) N/A; Aslan, Gamze; Yıldız, Ömer; Bengisu, Hale; Mutluer, Ferit Onur; Karaoğuz, Mustafa Remzi; Doctor; Doctor; Doctor; Doctor; Doctor; N/A; N/A N/A; N/A; N/A; Koç University Hospital; N/A; N/A; N/A; N/A; N/A
    A 24-year-old primigravid woman at 28 weeks of gestation was admitted to the hospital because of drug-refractory atrial tachycardia and heart failure. The arrhythmia did not respond to drug therapy and electrical cardioversion. Since tachycardia was intractable and had potentially life-threatening consequences for mother and fetus, it was decided to ablate the tachycardia after a multidisciplinary meeting. During the procedure, maternal hypotension occurred, consequently causing persistent fetal heart rate reduction. Radiofrequency ablation was immediately cancelled and emergency cesarean section was carried out. At 72 hours after the caesarean-section, successful RF ablation could be performed. Mother was discharged on the 7. postoperative day. The newborn was hospitalized until having reached 2500 g and he was discharged in good condition. Mother's left ventricle systolic function significantly improved and no atrial tachyarrhythmia was observed on the 6th month follow-up visit.
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    Comparison of long-term follow-up in patients with single or dual chamber pacemakers: is downtrodden or take its rightful place?
    (Edizioni Minerva Medica, 2019) Usalp, Songul; Demircan, Sabri; Baskurt, Murat; Kaplan, Ozgur; Canbolat, Ismail; Ciftci, Cavlan; Yazicioglu, Nuran; N/A; Yıldız, Ömer; Doctor; N/A; Koç University Hospital; N/A
    Background: In this study, at a median follow-up of 7.9 years (3-22), the patients who had implanted either single chamber (VDD) or dual chamber (DDD) pacemakers were compared according to the changes in left ventricular function, pacemaker-related complications, and mortality. Methods: In between January 1985 and August 2016, a total of 1238 patients, who presented with a diverse set of clinical situations and had implanted a single or double chamber pacemaker were retrospectively included in the present study. Age, prior history of hypertension, diabetes mellitus, heart failure and coronary artery disease did not differ between the groups (P>0.05). Results: When pre-implantation echocardiographic data was compared to the post-implantation values, in both groups, there were a significant decrease in LVEF (P<0.001) and increase in LVEDD (P<0.001), LA size (P<0.001) and sPAP (P<0.008). Results: When the patients who had a pacemaker due to a complete AV block were analysed, regardless of having VDD or DDD pacemaker, a significant decrease in LVEF was observed (P<0.0001). When the current rhythm at the last visit was evaluated, we found that patients with VDD were mostly in sinus rhythm (P<0.001). During the long-term follow-up, pacemaker-related complications (tamponade, infection, and pneumothorax) did not differ between the two groups (P>0.05). The comparison of the two pacemaker groups according to the decline in LVEF (<=% 40) did not show any significant difference (P=0.122). Conclusions: Patients with VDD or DDD pacemakers have both a decline in LVEF and an increase in LV diameter during the long-term follow-up. Mortality and complication rates were not different between the two groups. When compared to the DDD group, left ventricular dimensions and functions were better preserved in VDD group.
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    PublicationOpen Access
    Retrograde transcatheter closure of anterior mitral valve leaflet perforation
    (Medknow Publications, 2019) N/A; N/A; Şengün, Berke; Yıldırım, Işıl Şafak; Yıldız, Ömer; Çeliker, Alpay; Undergraduate Student; Other; School of Medicine
    Transcatheter closure of mitral valve leaflet perforation is a very rarely performed and a difficult procedure for repairing the defect. Herein, we are the first to report on both the safety and feasibility of percutaneous retrograde transcatheter closure of anterior mitral valve leaflet perforation with an AMPLATZER (TM) Duct Occluder II (6 mm x 6 mm; ADO II; Abbott Vascular, IL, USA) device in a 19-year-old patient with a severe mitral valve regurgitation following cardiac surgery.