Surgical pitfalls of minimally invasive direct coronary artery bypass procedure from the viewpoint of a surgeon in the learning curve

Introduction: Minimally invasive direct coronary artery bypass grafting (MIDCAB) offers arterial revascularization of the left anterior descending (LAD) coronary artery especially in lesions unsuitable for percutaneous coronary interventions. By avoidance of sternotomy and cardiopulmonary bypass its invasiveness is less than that of conventional bypass surgery. Aim: We in this study discuss our surgical experience in the MIDCAB procedure. Material and methods: Thirteen patients were operated on with the MIDCAB procedure. The inclusion criteria for MIDCAB were pure LAD disease totally occluded or severely stenotic. Patient demographics and preoperative and postoperative data were analyzed. Results: Mean age of the patients was 60.0 ±8.6 years. Patients' preoperative and postoperative levels of cardiac CK-MB (creatine kinase MB) were not significantly different (p = 0.993). However, cardiac troponin I (p < 0.001), hemoglobin (p < 0.001) and hematocrit (p < 0.001) were significantly different. No perioperative myocardial infarctions or cerebrovascular accidents were seen. The patients were discharged at a mean day of 4.77 with oral antiaggregant therapy. No mortality was seen in the study population. Conclusions: Minimally invasive direct coronary artery bypass is associated with few perioperative complications. Minimally invasive direct coronary artery bypass in our experience is a very good option for single vessel LAD disease

A simple heart valve replacement technique which improves surgical time

Aim of the study: Different heart valve replacement techniques have been described in the literature. In the present study, a simple and very fast heart valve replacement technique is presented. Material and methods: In a two-year period, 87 patients with the diagnosis of mitral valve disease, aortic valve disease or combined valve disease underwent valve replacement performed by the same surgeon. In this technique, the valve was implanted with the valve clamped to the surgical dressing without the assistant holding it. Patients with coexisting surgical pathologies were excluded from the study. A control group was created among the patients who were operated on during the same time period by different surgeons with the assistant holding the prosthesis. Control group operations were done by conventional valve holding and suturing techniques. Results: Mean age of the patients was 61.6 ± 3.2 years. Mitral valve replacement (MVR) was done to 51 patients, aortic valve replacement (AVR) to 12 patients and both aortic and MVR to 24 patients. Aortic cross clamp duration was 30.7 ± 3.3 min for MVR, 34.8 ± 6.2 min for AVR and 69.1 ± 6.1 min for both valve replacements. Aortic clamping durations were significantly higher in the conventional implantation technique. Discussion: The described technique has many advantages such as short myocardial ischemia duration, better exposure of the surgical field and facilitation of assistance. © 2014 Termedia Sp. z o.o. All rights reserved

Simple left atrial reduction in giant left atrium accompanying mitral stenosis

A patient with giant left atrium due to rheumatic mitral valve disease with spontaneous echocardiographic contrast in the giant left atrium is presented in this case report. The left atrial diameter reduction from dimensions of 118 × 104 mm to 80 × 77 mm was attained by excision of two-centimeter wide strips of left atrium on both sides by widely plicating the left atrial appendage from the inside with running polypropylene sutures. Spontaneous echocardiographic contrast disappeared in the postoperative echocardiographic control. The patient had uneventful recovery in the postoperative period and was discharged on the fifth day after the operation

An extensive calcified left ventricular aneurysm: Case report

A calcified left ventricular aneurysm (CLVA) is a rare, serious complication of acute myocardial infarction. It can lead to angina pectoris, thromboembolism of ventricular origin, ventricular arrhythmia, ventricular pseudoaneurysm or rupture, progressively enlarging aneurysms, congestive heart failure, and death. Treatment is surgical for symptomatic or asymptomatic LVAs larger than 5 cm, particularly when there is comorbid coronay artery disease. Its standard treatment is a ventriculoplasty and aneurysmectomy using the Dor technique. The aim of surgical treatment of an LVA is to reduce oxygen consumption in the LV by reducing end-diastolic volume (EDV), creating the ideal ventricle geometry, and preventing thrombus formation. The surgical results are often good. This article presents a patient with CLVA in whom we performed surgery. Copyright © 2016 by Türkiye Klinikleri

Bileaflet versus posterior-leaflet-only preservation in mitral valve replacement

In the present study of mitral valve replacement, we investigated whether complete preservation of both leaflets (that is, the subvalvular apparatus) is superior to preservation of the posterior leaflet alone. Seventy patients who underwent mitral valve replacement in our clinic were divided into 2 groups: MVR-B (n=16), in whom both leaflets were preserved, and MVR-P (n=54), in whom only the posterior leaflet was preserved. The preoperative and postoperative clinical and echocardiographic findings were evaluated retrospectively. No signs of left ventricular outflow tract obstruction were observed in either group. In the MVR-B group, no decrease was observed in left ventricular ejection fraction during the postoperative period, whereas a significant reduction was observed in the MVR-P group (P=0.003). No differences were found between the 2 groups in their need for inotropic agents or intra-aortic balloon pump support, or in cross-clamp time, duration of intensive care unit or hospital stays, postoperative development of new atrial fibrillation, or mortality rates. Bileaflet preservation prevented the decrease in left ventricular ejection fraction that usually followed preservation of the posterior leaflet alone. However, posterior leaflet preservation alone yielded excellent results in terms of decreased left ventricular diameter. Bileaflet preservation should be the method of choice to prevent further decreases in ejection fraction and to avoid death in patients who present with substantially impaired left ventricular function. © 2014 by the Texas Heart ® Institute, Houston

Proximal aortic arch cannulation for proximal ascending aortic aneurysms

Introduction: Different arterial inflow sites have been reported to date for particularly challenging cardiac operations. The ascending aorta, femoral artery, and subclavian artery are the most commonly used sites. Although its use has been reported, the aortic arch has not gained popularity in the performance of cannulation. According to a search performed in the PubMed database, aortic arch cannulation for ascending aorta replacement has not been examined in a separate study before. In the present study, we report the treatment outcomes of patients with ascending aortic aneurysms in whom the aortic arch was cannulated for arterial inflow. Material and methods: Twenty-seven patients with aneurysmal dilatation of the ascending aorta underwent ascending aorta replacement from April 2010 to March 2013. The mean age of the patients was 64 years. All operations were carried out by cannulating the aortic arch distally from the origin of the innominate artery. Results: There was no mortality or cannulation-related morbidity. In 23 patients, only the supracoronary ascending aorta was replaced, whereas in 4 patients, the button modification of the Bentall procedure was performed to replace the root and the ascending aorta. Conclusions: The technique of aortic arch cannulation distal to the origin of the innominate artery is worthy of consideration in the treatment of aneurysms limited to the ascending aorta due to its safety, simplicity, and low morbidity

Long onlay bypass grafting using the left internal mammary artery for proximal and mid stenosis of the left anterior descending artery

Aim of the study: According to the literature, many surgeons aim to obtain complete revascularization during coronary artery surgery. This becomes an issue when the left anterior descending (LAD) artery is diffusely diseased. This study presents the results of revascularization surgery of LAD arteries with multiple stenoses and the subsequent angiographic control examinations. Material and methods: Forty-seven patients with proximal and mid-segment left anterior descending (LAD) artery disease were included in the study. Left anterior descending arteries were bypassed with left internal mammary arteries (LIMAs). Left anterior descending arteries were longitudinally opened over the mid stenotic segments 4-5 mm distally and proximally from the stenosis. The LIMAs were then anastomosed to the LAD arteries with a running suture, using 7-0 polypropylene sutures. Thirteen patients, who provided their informed consent, were angiographically evaluated at a mean of 12.5 ± 3.7 months after the operation (range 6-18 months). Results: The mean age of the patients was 64.1 ± 8.9 years. The mean number of distal anastomoses was 3.5 ± 0.9 (range 1-6). The mean length of LAD anastomoses was 1.88 ± 0.54 cm (range 1.5-4 cm). Cardiac troponin I levels were below perioperative myocardial infarction thresholds. Mean postoperative hospitalization was 6.10 ± 0.98 days (range 5-9 days). There was no mortality in the study group. Control angiography revealed patent bypass grafts in all patients. Conclusions: Long anastomosis to the LAD artery provides excellent mid-term patency. It is safe and effective in perfusing the proximal and distal non-stenotic segments of the LAD artery, as well as in perfusing the unoccluded side branches originating from the stenotic segments. © 2014 Termedia Sp. z o.o. All rights reserved

Unilateral or bilateral cerebral perfusion in hemiarch replacement: A prospective randomized study

Background: We designed a prospective randomized clinical study to compare unilateral and bilateral antegrade cerebral perfusion (ACP) under moderate hypethermia in open distal aortic hemiarch replacement in ascending aortic aneurysm. Methods: Forty-two patients were prospectively randomized into two groups; unilateral ACP to Group 1 and bilateral ACP to Group 2. Inclusion criteria were pathological aortic aneurysm in the ascending aorta and/or aortic arch, elective operation, normal preoperative carotid Doppler ultrasonography, and nonexistence of preoperative neurological event. Patients were evaluated with preoperative and postoperative biochemical blood analysis, magnetic resonance imaging (MRI), and neurological disorders. The primary endpoints were permanent neurological disorder and death. Results: There were 21 patients in each group. Mean age was 56.57 ± 10.06 years in Group 1 and 50.95 ± 15.64 years in Group 2 (p =.170). No significant difference was found according to demographic data. ACP times were significantly higher in bilateral ACP (Group 1: 12.62 ± 5.04 min, Group 2: 18.23 ± 9.04 min, p =.018) whereas cross-clamp time and cardiopulmonary bypass times were not (p =.693 and p =.584 sequentially). Transient neurological disorder was found in seven patients in Group 1 and in 4 patients in Group 2 (p =.484). Postoperative MRI revealed new milimetric ischemic zones in three patients in Group 1 but none in Group 2. No permanent neurological disorder or mortality was seen. Conclusion: The present randomized clinical prospective study could not prove the superiority of one of the technique in cerebral protection probably because, our overall ACP time was too short. © 2020 Wiley Periodicals LL

Determination of Optimum Flotation Parameters of Zonguldak Fine Hard Coal by Using Efficiency Index

Kömür madenciliğinde mekanizasyona bağlı olarak ince kömür üretimi düzenli bir şekilde artmaktadır. Flotasyon mevcut durumda ince kömürlerin zenginleştirilmesinde kullanılan en etkili yöntemdir. Temiz kömür külü ve yanabilir verim flotasyon işleminin değerlendirilmesinde en yaygın olarak kullanılan parametrelerdir. Kömür yıkama performansı verimlilik indeksi olarak adlandırılan basit bir indeks ile değerlendirilebilir. Bu indeks çeşitli işletme koşulları altında temizleme işlemlerinin performansının karşılaştırılmasında kullanılan bir parametredir. Bu çalışmada, Zonguldak-Kozlu bölgesi % 46,10 küllü kömür numuneleri üzerinde yapılan deneylerde en uygun flotasyon parametreleri verimlilik indeksi ile tespit edilmiştir. En uygun tane boyutu, toplayıcı cinsi ve miktarı, köpürtücü cinsi ve miktarı ve bastırıcı miktarı tespit edilmiştir. Sonuçta % 55,48 ağırlığında ve % 18,84 küllü kaba temiz kömür elde edilmiştir. Ayrıca yapılan temizleme flotasyonunda nihai temiz kömür % 36,43 ağırlık oranında, %12,78 külde elde edilmiştir.According to the improvement of coal mining mechanization techniques, the proportion of fine coal has been regularly increased. Flotation is still the most effective method of fine coal benefication in the present case. Clean coal ash and combustible recovery are commonly used flotation evaluation parameters. Coal cleaning performance can be evaluated by a simple index called efficinency index. This index is a useful parameter to compare the relative performances of the cleaning operation under the various operating conditions. In this study, the optimal flotation parameters of Zonguldak- Kozlu fine hard coal having 46.10% ash content were determined by using efficiency index. It was determined optimal particle size, collector type and dosage, frother type and dosage and depressant dosage. As a result, the rougher clean coal having 55.48% by weight and 18.84% ash content were obtained. Moreover, the clean coal having 36.43% by weight and 12.78% ash content were obtained in the cleaning flotation stage