Cem Yorgancioglu

Clinical performance and biocompatibility of poly(2-methoxyethylacrylate)-coated extracorporeal circuits

BACKGROUND Poly(2-methoxyethylacrylate) is an amphiphilic organic polymer consisting of a hydrophobic backbone with pendant hydrophilic groups that has been reported to reduce protein and platelet adsorption in in vitro and ex vivo studies. METHODS Sixty patients undergoing three-vessel coronary artery bypass grafting were divided into two equal groups. Group 1 had operation with Capiox poly(2-methoxyethylacrylate) coated SX18R oxygenators with noncoated circuits, and group 2 had operation with all noncoated circuits. Hemodynamic variables, blood and urine test results, hematologic variables, complement fractions, C3a and C4d, and interleukin-6 levels were documented preoperatively (T1), on cardiopulmonary bypass (T2), before cessation of cardiopulmonary bypass (T3), after protamine sulfate reversal (T4), and on the first postoperative day (T5). Protein electrophoresis was performed at T1 and T5. Blood cell adhesion and aggregation on fibers were analyzed with optical microscopy, and desorbed protein was evaluated quantitatively by a spectrophotometer using samples obtained when the oxygenators were dismantled after cardiopulmonary bypass. RESULTS Platelet counts in group 1 demonstrated significant differences at T3, T4, and T5 (p < 0.05) versus group 2 and white blood cell counts in group 1 versus group 2, at counts T4 and T5. Albumin levels were significantly better preserved in group 1 at T4, and T5 and fibrinogen levels, at T3 and T5 (p < 0.05). On electrophoresis, the postoperative albumin level was 57.9% +/- 3% in group 1 versus 50.2% +/- 3% in group 2 (p < 0.05). Postoperative hemorrhage was 452 +/- 35 mL in group 1 and 612 +/- 35 mL in group 2 (p < 0.05). Duration of intubation was significantly lower (p < 0.05) in group 1, as was need of blood transfusion (p < 0.01). More platelet adhesion and aggregation were demonstrated on noncoated oxygenator fibers. The amount of desorbed protein was 0.13 +/- 0.01 mg/dL versus 0.012 +/- 0.001 mg/dL (p < 0.001) on noncoated versus coated fibers, respectively. CONCLUSIONS Poly(2-methoxyethylacrylate)-coated oxygenators reduce platelet adhesion, platelet aggregation and protein adsorption. This surface provides a better perioperative clinical status through platelet-, albumin-, and fibrinogen-sparing effects.

Amiodarone versus digoxin and metoprolol combination for the prevention of postcoronary bypass atrial fibrillation

OBJECTIVE This prospective randomized study aims at evaluation and comparison of the prophylactic effects of amiodarone versus digoxin and metoprolol combination in postcoronary bypass atrial fibrillation. METHODS A total of 241 consecutive patients undergoing elective coronary artery bypass grafting were randomly allocated into three groups. Patients in Group1 (n=77) received metoprolol 100 mg/24 h per oral (P.O.), preoperatively, 2x0.5 mg digoxin intravenously on the operating day and digoxin 0.25 mg P.O.+metoprolol 100 mg P.O. on the first postoperative day until discharge. Patients in Group 2 (n=72) received totally 1200 mg intravenous/24 h amiodarone which the 300 mg - bolus dose/1 h was given as soon as the operation had been finished. On the next day patients were administered 450 mg/24 h amiodarone i.v. and 600 mg/day in three doses P.O. were given until discharge. Group 3 (n=92) was the control group with no antiarrhythmic prophylaxis. RESULTS Preoperative patient characteristics and operative parameters were similar in three groups. Atrial fibrillation occurred in 13 patients (16.8%) in Group 1, six patients (8.3%) in Group 2 and 31 patients (33.6%) in Group 3. CONCLUSION Both study groups were effective in the prevention of postcoronary bypass atrial fibrillation with respect to control (P<0.01 in Group 1 and P<0.001 in Group 2).

Coronary artery bypass surgery without cardiopulmonary bypass.

In the years 1994 and 1995, 1087 patients underwent coronary artery bypass grafting at our institution. Of these, 297 were operated on without cardiopulmonary bypass. 239 were male, and 58 were female. Their ages ranged from 28 to 81 years (54.43 +/- 9.63). Of the total, 294 were operated on electively, two as a coronary reoperations, and one as an emergency after a failed percutaneous transluminal coronary angioplasty procedure. In all patients complete revascularization was the aim, and a cardiopulmonary bypass team was kept on standby. Median sternotomy was performed as the exposure in all patients, except a patient who underwent a coronary reoperation through a left thoracotomy incision. The average of the distal anastomoses was 1.51 +/- 0.6, ranging from 1 to 3. The left internal thoracic artery was used in 292 operations, which was an individual graft in 284, a sequential graft in five, and a free graft in four. Major complications in the early postoperative period were noted in three patients as reoperation for excessive bleeding. One patient had reoperation for left internal thoracic artery spasm, and one patient had lower extremity ischemia caused by intraoartic balloon counterpulsation. Hospital mortality was 0.3% with one patient. It is our belief that in selected cases coronary artery bypass grafting without cardiopulmonary bypass is a safe procedure with the advantage of improvement in recovery during the postoperative period.

Angiographic Assessment of Sequential and Individual Coronary Artery Bypass Grafting

Abstract  Objective: In trying to answer the question about the controversial use of sequential grafts, we determined the mid‐term angiographic outcome of patients in whom coronary artery bypass was performed with different types of vein grafts. Methods: A total of 1034 coronary anastomoses on 724 saphenous vein grafts (SVGs) (apart from 497 left internal mammarian artery (LIMA) anastomoses) were assessed in 509 patients in an average of 55.4 ∓ 17.6 months after coronary artery bypass grafting. Results: The patency rates of sequential conduits were markedly higher than those of individual ones (86.6% vs 69.6%, p = 0.0001). Also, the anastomoses on the sequential conduits had better patency rates (80.6% vs 69.6%, p = 0.0001). This difference was even more pronounced in coronary arteries of poor quality/small (<1.5 mm) diameter (68.9% vs 51.6%) for the sequential and individual grafts, respectively (p = 0.03). Also, the patency of the entire sequential conduit was lower when most distally located anastomosis was of poor runoff (45.2%). Conclusions: The patency of a sequential vein conduit is generally superior than that of an individual one, especially for poor runoff coronary vessels, provided that the most distally located anastomosis is performed on a good coronary artery in terms of quality and diameter. Using a minimal length of SVG is another advantage. However, failure of a single sequential conduit jeopardizes all of the anastomoses along that graft segment. Besides, being technically more demanding, technical expertise in performing a sequential anastomosis is probably among the important predictors of patency. (J Card Surg 2003;18:524‐529)

An unusual experience with posterior pericardiotomy

There are some recent reports on the effect of posterior pericardiotomy to the postoperative supraventricular tachyarrythmias (SVT). Although controversy still exists on its effect on atrial ®brillation, its clinical bene®t on pericardial tamponade is satisfactory [1±3]. To test its effectiveness on SVT we started performing posterior pericardiotomy where we experienced an unusual case on the 29th patient. A 55 year old man with left main coronary stenosis besides two vessel disease, normal ventriculography and ejection fraction 65% was operated in standard fashion with a roller pump, non-pulsatil ̄ow (2.0±2.4 l/min), Polystan membrane oxygenator, 328C systemic hypothermia, single cross clamp, initial antegrade 1 retrograde cold blood cardioplegia, repeated cold retrograde blood cardioplegia every 20 min, and a hot shut before the removal of the cross clamp. LIMA grafting to the LAD and sequantial saphenous graft to ®rst diagonal, intermediate and obtuse marginal arteries were performed. After an uneventful operation ( £ clamp time 42 min, total perfusion time 58 min) the patient was placed in the ICU ward where the patient deteriorated with lateral ST elevation and multifocal ventricular arrhythmias, which did not respond to the medical therapy, continued with ventricular ®brillation (VF), which also did not respond to de®brillation. The patient returned to the operating room urgently and re-explored. After reopening the sternum VF had been over come following the ®rst de®brillation with internal paddles. The hemodynamia returned to normal in a short time with positive inotrops followed by ST normalisation. All the bypass grafts were patent, nothing unusual was observed. Following haemostasis sternum was wired again. But by the time of cutaneous sutures, the ST elevation relapsed, the hemodynamia failed quickly, VF re-occurred. The sternum was reopened in a short time and the heart was de®brillated again. Grafts were patent again, but an ischaemic colour change was observed on the lateral and posterior aspect of the heart. On careful examination we had observed that a segment of saphenous graft (just before and after the intermediate artery anastomosis) and left atrial appendage protruded from the posterior pericardiotomy. The saphenous graft was squeezed by the edges of the posterior pericardiotomy incision. After closing the posterior pericardiotomy incision by primary sutures, and insertion of an intra-aortic balloon from left femoral artery the patient was taken to the ICU ward again. Reperfusion arrhythmia was controlled by amiodorone infusion. Postoperative peak CK-MB (mass) value was 42 ng/ml and Troponin T was 4.85 ng/ml, no Q waves were noted in electrocardiograms. Following an uneventful 5 days in the ICU the patient was discharged in his 10th postoperative day with lateral hypokinesia in echocardiography taken on the 8th day postoperatively. Posterior pericardiotomy is effective on early and late pericardial tamponade, can be effective on the incidence of SVT, but after this case in our opinion, should carefully be used with patients in whom posterior wall revascularization was performed especially by sequential grafting.

Comparison of circadian rhythm characteristics of blood pressure and heart rate in patients before and after elective coronary artery bypass surgery.

Coronary artery bypass grafting surgery (CABGS) is done to reperfuse the ischemic myocardium of coronary disease patients. This study was designed to analyze the circadian rhythm characteristics of blood pressure (BP) and heart rate (HR) of patients before and after CABGS. Fifty-one patients undergoing elective CABGS were studied; 21 patients received one, 12 two and 18 three or more grafts. BP was monitored for 24h before and after CABGS while patients were recumbent in the hospital. Systolic (S) and diastolic (D) BP and HR were assessed every 30min. Of the 51 patients, 37 (73%) had nondipper 24h BP patterns (nocturnal decline in BP<10% of daytime mean level) in the preoperative baseline assessment. The peak and MESOR (rhythm-adjusted 24h mean) values of the circadian rhythm in SBP, DBP, and pulse pressure (PP) significantly declined following surgery, while HR and rate-pressure product (RPP=SBP×HR) markedly increased. The double amplitude (peak-to-trough variation) of the circadian rhythm in SBP and DBP was significantly reduced postoperatively, and that of the rhythm in HR and RPP significantly increased. The slopes of the morning rise and evening dip in the 24h SBP profile were reduced significantly after bypass grafting. The corresponding slopes of the HR profile, in contrast, were markedly increased.

Does microalbuminuria in diabetic patients affect the postoperative course after coronary artery bypass surgery

OBJECTIVES Microalbuminuria is a predictor of microvascular disease and a marker for multiorgan damage in diabetic patients. It has been proposed that in diabetic patients who would undergo coronary artery bypass surgery (CABG), microalbuminuria is associated with poor postoperative outcome, higher incidence of early and late morbidity and mortality. METHODS Microalbuminuria was prospectively studied preoperatively in 24-h urinary collections for 257 consecutive diabetic patients in a 2-year period. One hundred and sixty-eight patients (65.4%) were defined as microalbuminuria negative (Group A), and 89 (34.6%) were microalbuminuria positive (Group B) with respect to the cut-off point 30 mg/24 h. RESULTS The two groups did not differ with respect to preoperative and operative data, except that preoperative blood glucose levels (P=0.046), blood urea nitrogen (P=0.001), and creatinine (P=0.001) were higher and creatinine clearance was lower (P=0.025) in Group B. Postoperative serum creatinine levels on different days were higher in microalbuminuria positive patients (P=0.04). Also, positive inotropic agent usages at the time of leaving the operating room (21.3 vs. 10.1%; P=0.013) and on the 1st day in the intensive care unit (ICU; 29.2 vs. 14.9%; P=0.014), ICU stay day (2.3+/-2 vs. 2.4+/-1.6; P=0.02) and also atrial fibrillation rate (30.3 vs. 17.9%) were higher in Group B (P=0.019). Total hospital stay (7.5+/-2.9 vs. 7.2+/-1.3) was similar. The 30-day mortality was 5.6 times higher (3.4 vs. 0.6%) but statistically not significant (P=0.088) in Group B. The mean follow-up was 30.6+/-16. 2 months in total (30.9+/-16.2 in Group A and 30.1+/-16.5 in Group B). There were 12 late deaths, nine were cardiac, and no differences were detected between groups. CONCLUSIONS Our findings suggest that postoperative period may be more problematic in diabetic patients with microalbuminuria, but microalbuminuria does not seem to have a major effect on the postoperative course in patients undergoing CABG.

Surgical management of left ventricular aneurysms by endoventricular pericardial patch plasty.

BACKGROUND Early and late surgical outcomes of endocardial resection and aneursymectomy repaired with an autologous pericardial patch were studied. METHODS We studied 125 patients who underwent endoaneurysmorrhaphy with pericardial patch during the period from June 1993 until June 2000. Preoperative, early and late postoperative results, annual postoperative echocardiography of all patients and hemodynamic controls of 35 patients within a mean follow-up of 64+/-8 months were analyzed. RESULTS Mean NYHA improved to postoperative 2.1+/-0.5 from preoperative 2.8+/-0.4. Mean number of bypass grafts was 2.6+/-1.1. Left ventricular ejection fraction rate improved to 36.2+/-8% in one month, 39.3+/-9% in 6 months, 42.3+/-8% in one year versus preoperative 29.2+/-9% (P< or =0.05).Perioperative mortality was 6.4% (eight patients) and 11 deaths were observed in the late follow-up (9.4%). CONCLUSION Endoaneurysmorrhaphy with pericardial patch may be an alternative option in the management of left ventricular aneurysms within acceptable surgical results.

Chlamydia and atherosclerotic coronary arterial disease in Turkey.

OBJECTIVE Chlamydia pneumoniae, which is a Gram(-) intracellular bacteria, besides being a respiratory pathogen, is thought to play an active role in the progress of acute myocardial infarction and chronic coronary artery disease. In this study we aim to determine the frequency of C. pneumoniae in coronary artery lesions of Turkish people. METHODS AND RESULTS The atherosclerotic material taken from 8 cases by directional atherectomy and from 23 cases by surgical endarterectomy and examined by indirect immunofluorescence (IIFA) test and polymerase chain reaction (PCR). C. pneumoniae positivity was 32.3% (10/31) by IIFA and 29.0% (9/31) by PCR while the evaluation of the methods together yield a positivity of 35.5% (11/31). CONCLUSIONS A statistically significant difference could not be established between C. pneumoniae positive and negative groups according to age and the classical atherosclerotic risk factors such as diabetes mellitus, smoking, hypercholesterolaemia, hypertension, family history; besides, a statistically significant difference could not be found between the presence of C. pneumoniae and the severity and clinical picture of coronary artery disease.

Coronary Artery Bypass Grafting without Cardiopulmonary Bypass

Between March 1994 and April 1998, 2869 patients underwent coronary artery bypass grafting at our institution. Of these, 415 (14.5%) with a mean age of 54.4 ± 9.9 years were operated on without cardiopulmonary bypass. Internal thoracic artery was used in 402 cases (97%) and the left anterior descending artery was revascularized in all except 1. Distal anastomoses ranged from 1 to 3, with a mean of 1.45 ± 0.58. Major postoperative complications comprised reoperation because of internal thoracic artery spasm in 1 patient, lower extremity ischemia due to intraaortic balloon pumping in 1 patient, revision for excessive bleeding in 3, and perioperative myocardial infarction in another 3. Hospital mortality was 1.2% (5 deaths). Coronary angiography was performed in 38 patients, 1 to 44 months postoperatively. Examination of 56 distal anastomoses revealed a patency rate of 86.1% for internal thoracic artery grafts and 55% for saphenous vein grafts. It was concluded that coronary bypass surgery without cardiopulmonary bypass gave favorable results in the early postoperative period. However, considering the late graft patency rates, either patient selection or the technique should be reevaluated.