Evaluation of Anastomosis Efficiency in Arteriovenous Shunts Created by Using Hand-Sewn Microsurgery and Microvascular Anastomotic Coupler Device

OBJECTIVE

Microsurgery has made great contributions to the advancement of surgery. In parallel with the developments in microsurgery, various techniques have been developed to perfect the technique. Microvascular anastomotic coupler device (MACD) is one of these techniques. The aim of the study was to evaluate the effectiveness of anastomoses created by using hand-sewn microsurgery (HSM) and MACD.

METHODS

Twenty male Sprague-Dawley rats weighing 250 to 300 g were divided into 2 groups randomly. Arteriovenous shunt was performed between carotid artery and internal jugular vein with the principles of HSM in the first group (n=10) and by using the 1-mm anastomotic microvascular device in the second group (n=10). Groups were evaluated for anastomose time, success of anastomosis, thrombosis formation, color Doppler ultrasonography, and histopathological features.

RESULTS

Anastomotic time was faster with the coupler device compared with HSM technique. Flow rates were found significantly higher in the MACD group. Endothelialization and wall integrity rates were better in MACD group.

CONCLUSIONS

Microvascular anastomotic coupler device is faster than HSM. High quality and durability of vascularization, insignificant foreign body reactions are histopathological advantages of MACD.

Rare vascular involvement in Behçet's disease: Coronary artery pseudoaneurysm

Behçet's disease is a relapsing, inflammatory, multi-systemic disease. Coronary arterial involvement in Behçet's disease is very rare with a prevalence of less than 0.5%. We report the case of a 34-year-old man who presented with a coronary artery pseudoaneurysm associated with Behçet's disease. The patient underwent a successful left internal thoracic artery to left anterior descending artery bypass graft procedure, and remains symptom-free in a 6-month follow up with normal electrocardiogram.

A combination of severe complications in a case of infective endocarditis: Dehiscence of prosthetic aortic valve, aortic dissection, pseudoaneurysm, and hematoma causing right ventricular collapse

Prosthetic valve endocarditis with mechanical complications causing pulmonary edema is fatal, therefore it needs to be diagnosed early and should be treated surgically in emergency setting. Transesophageal echocardiogram is crucial for recognizing the mechanical complications, which can be encountered on daily practice, but the coexistence of complications occurring on different mechanism is rather uncommon. Herein, we report a 21-year-old gentleman presenting with acute heart failure, whose imaging tests showed a combination of dehiscence of mechanical aortic valve prosthesis, aortic dissection, pseudoaneurysm, and hematoma causing right ventricular collapse.

The role of immature platelet count and immature platelet fraction in determining the need for transfusion in patients undergoing CABG

BACKGROUND

Platelet dysfunction has been shown to play a role in postoperative bleeding, however it is not clear whether immature platelets (IP) can induce appropriate homeostasis to prevent excessive bleeding in patients undergoing coronary artery bypass grafting (CABG). The aim of this study was to evaluate the postoperative change in IP count (IPC), IP fraction (IPF) and mean platelet volume (MPV), and to examine their relationship with postoperative bleeding and blood transfusion.

METHODS

One hundred and forty-nine consecutive patients undergoing elective CABG were included in this prospective study. All CABGs were performed by the same surgical team in a standardised method, utilising the on-pump technique. IPC, MPV and IPF were measured pre-operatively, after the completion of surgery, and at the postoperative first, third and fifth days. The primary outcome measure of this study was whether the need for transfusion was associated with IP, IPF, MPV and platelet count.

RESULTS

There was a significant decrease of 7.77% in IPC on the day of the operation. Pre-operative IPC and IPF were correlated with postoperative drainage (p < 0.001), intraoperative blood transfusion (p < 0.001) and intensive care unit blood transfusion (p < 0.001). Pre-operative haemoglobin levels were significantly correlated with length of hospital stay. However, neither pre-operative IPC nor IPF were associated with length of hospital stay. Postoperative IPC was however associated with the length of hospital and intensive care unit stay (p = 0.008 and p = 0.009, respectively).

CONCLUSIONS

Pre-operative IPC and IPF were significantly correlated with postoperative drainage and blood transfusion frequency. In patients undergoing CABG, these can be seen as serious guiding parameters in the estimation of postoperative bleeding.

Is Biochemical Follow Up Possible in Peripheral Arterial Disease Treatment: Hypoxia Inducible Factor-1 Alpha?

Purpose

The hypoxia inducible factor (HIF)-1 is a dimeric protein complex that plays an integral role in the body’s response to hypoxia. This study aimed to analyze the regulation of HIF-1α following vascular and/or endovascular surgery in peripheral arterial disease (PAD) patients.

Methods

Materials and A total of 40 patients with PAD (≥Rutherford category 3) were included in this prospective study. The mean age was 61.9±9.2 years. Open surgery was performed in 16 patients, and endovascular intervention was performed in 34 patients. At preoperative (T1), postoperative day 1 (T2), and month 3 (T3), the serum HIF-1α levels were checked using the ELISA technique.

Results

At T3, the ankle-brachial index was significantly higher than the preoperative value (P<0.001). Serum HIF-1α levels at T1, T2, and T3 were 2.0±1.7 ng/mL, 1.9±1.7 ng/mL, and 1.6±1.4 ng/mL, respectively. Serum HIF-1α levels between T1 and T3 and between T2 and T3 were significantly different (P<0.05). The preoperative HIF-1α levels were lowest in iliac lesions compared to femoropopliteal or tibial lesions.

Conclusion

The HIF-1α levels were decreased in all patients on postoperative days, T2 and T3, compared with the preoperative values. Our results indicated that HIF-1α may be a surrogate marker after revascularization in patients with PAD. Further studies are needed to analyze the sensitivity, specificity, and cut-off values of HIF-1α in patients with PAD.

Successful treatment of massive pulmonary embolism in a pregnant woman complicated with atypical hemolytic uremic syndrome

The treatment of the massive pulmonary embolism concomitant hemodynamic instability in pregnancy is difficult and controversial and carries a high risk for both the baby and the mother. The catheter-directed thrombectomy with or without extracorporeal membrane oxygenation support may be a suitable management strategy in suitable cases but pregnancy-related complications may follow the treatment of pulmonary embolism and atypical hemolytic uremic syndrome should be considered in the differential diagnosis. We present a case of a 32-year-old patient who had a pulmonary embolism with shock in the 8th week of pregnancy complicated by atypical hemolytic uremic syndrome.

The Effect of Hemodynamic Parameters on Cerebral Oxygenization During Carotid Endarterectomy

INTRODUCTION

Near-infrared spectroscopy (NIRS) is a non-invasive technique to detect cerebral ischemia by monitoring changes in regional cerebral oxygenation (rSO₂) in the frontal lobes. However, there are no studies showing the changes in NIRS values in response to hemodynamic variations during stages of carotid endarterectomy (CEA) procedure and clinical implications of these changes. The aim of this study was to determine if hemodynamic changes affect NIRS values during carotid endarterectomy and if our results may help to provide strategies for hemodynamic management in these patients.

METHODS

A total of 50 consecutive patients undergoing CEA were prospectively included in the study. NIRS was measured at first minute after clamping of carotid artery, and then systolic blood pressure was increased above 150 mmHg. NIRS values from both hemispheres were recorded simultaneously at certain time points and were analyzed to evaluate the changes at different stages of operation and to assess correlations with hemodynamic parameters.

RESULTS

NIRS values on the right and left sides were correlated with systolic (right P<0.001, R2:0.24; left P=0.02, R2:0.10) diastolic (right P<0.001, R2:0.36; left P=0.001, R2:0.18) and mean (right P<0.001, R2:0.33; left P=0.003, R2:0.17) blood pressures when the patient was under general anaesthesia. NIRS values were significantly lower than pre-incision values just after clamping of carotid artery in both hemispheres (P=0.005 for the right and P<0.001 for the left side).

CONCLUSION

NIRS values measured in our study show that there is a correlation between hemodynamic changes and cerebral oxygenation. This effect is especially pronounced while the patient is asleep and intubated, which implies the importance of close monitoring of patients with carotid disease during any surgery requiring general anaesthesia.

Validation of German Aortic Valve Score in a Multi-Surgeon Single Center

OBJECTIVE:

Risk assessment for operative mortality is mandatory for all cardiac operations. For some operation types such as aortic valve repair, EuroSCORE II overestimates the mortality rate and a new scoring system (German AV score) has been developed for a more accurate assessment of operative risk. In this study, we aimed to validate German Aortic Valve Score in our clinic in patients undergoing isolated aortic valve replacement.

METHODS:

A total of 35 patients who underwent isolated open aortic valve replacement between 2010 and 2013 were included. Patients with concomitant procedures and transcatheter aortic valve implantation were excluded. Patients' data were collected and analyzed retrospectively. Patients' risk scores EuroSCORE II were calculated online according to criteria described by EuroSCORE taskforce, Aortic Valve Scores were also calculated.

RESULTS:

The mean age of patients was 61.14±13.25 years (range 29-80 years). The number of female patients was 14 (40%) and body mass index of 25 (71.43%) patients was in range of 22-35. Mean German Aortic Valve Score was 1.05±0.96 (min: 0 max: 4.98) and mean EuroSCORE was 2.30±2.60 (min: 0.62, max: 2.30). The Aortic Valve Score scale showed better discriminative capacity (AUC 0.647, 95% CI 0.439-0.854). The goodness of fit was x2HL=16.63; P=0.436). EuroSCORE II scale had shown less discriminative capacity (AUC 0.397, 95% CI 0.200-0.597). The goodness of fit was good for both scales. The goodness of fit was x2HL=30.10; P=0.610.

CONCLUSION:

In conclusion, German AV score applies to our population with high predictive accuracy and goodness of fit.

Paricalcitol counteracts the increased contrast induced nephropathy caused by renin-angiotensin-aldosterone system blockade therapy in a rat model

OBJECTIVE

The effect of vitamin D and renin-angiotensin-aldosterone system blockade medications in pathophysiology of contrast induced nephropathy (CIN) is controversial. The effects of paricalcitol (active vitamin D analogue) and losartan treatments in an experimental model of CIN were investigated in this study.

MATERIALS AND METHODS

Thirty-six male Wistar albino rats were examined in five treatment groups. Placebo group (Group A; n = 4) received no active medication; control group (Group B; n = 8) received only contrast media (CM); Group C (n = 8) received paricalcitol; Group D (n = 8) received losartan and Group E (n = 8) received paricalcitol plus losartan. CIN was induced by NG-nitro-L-arginine methyl ester and indomethacin before iohexol injection. Renal histopathological findings were categorized and renal immunohistochemical examinations by caspase-3 rabbit primary antibody were performed.

RESULTS

Creatinine and cystatin C levels significantly increased in the treatment groups, compared to Group A. However, creatinine levels were not significantly increased in Groups C, D and E compared to Group B. Compared to Group B, a significant increase of cystatin C levels was observed in Group D (p < 0.01). In Group E, when paricalcitol treatment was added to losartan treatment, cystatin C levels were similar to Group B (p = 1.00). In histopathological and immunohistochemical examination frequency of Grade 2/3 tubular necrosis and renal caspase 3 activity scores were significantly higher in the losartan treatment group compared to the other treatment groups. The histopathological effects related to losartan treatment were found to be reversed when paricalcitol treatment was combined.

CONCLUSIONS

Our findings suggest that paricalcitol treatment counteracts increased contrast induced nephropathy caused by losartan. These findings warrant further clinical studies to investigate the benefit of paricalcitol in CIN prophylaxis.

Time from cardiac catheterization to cardiac surgery: a risk factor for acute kidney injury?

OBJECTIVES

Acute kidney injury can occur after cardiac catheterization and cardiac surgery. The negative effects of the contrast media and cardiopulmonary bypass on renal function may be additive when performed in close succession. The results in the literature are, however, conflicting.

METHODS

Preoperative, operative, perioperative and postoperative variables of 573 consecutive adult patients who underwent cardiac surgery on cardiopulmonary bypass were collected prospectively. Acute kidney injury (AKI) was defined according to the Acute Kidney Injury Network criteria based on changes in serum creatinine level within 48 h of surgery.

RESULTS

Acute kidney injury was detected in 233 patients (41%). In a multivariate analysis, older age (P = 0.01), longer cardiopulmonary bypass time (P = 0.003), lower preoperative haematocrit level (P = 0.02) and higher body mass index (P = 0.001) were found to be independently associated with development of acute kidney injury. Analysis of the time from cardiac catheterization to surgery by logistic regression modelling did not show any significant change in the risk of acute kidney injury. Risk related to time from catheterization to surgery was not increased even in the patients with elevated preprocedural creatinine levels (>106 μmol l(-1); P = 0.23), left ventricular dysfunction (ejection fraction <40%; P = 0.19) and older age (≥70 years; P = 0.86).

CONCLUSIONS

The time from cardiac catheterization to cardiac surgery is not a risk factor for the development of postoperative acute kidney injury even in patients with other risk factors. Surgical intervention should not be delayed in emergency or urgent cases. The optimization of renal function seems to be the correct strategy in clinically stable patients with risk factors for acute kidney injury.

Left Atrial Leiomyosarcoma Extending into the Posterior Mediastinum and Mimicking a Left Atrial Myxoma

<p><strong>Background:</strong> Intracardiac malignancies are extremely rare and hard to detect or differentiate preoperatively.</p><p><strong>Case Report:</strong> We present a 48-year-old female patient who was diagnosed primarily with left atrial myxoma and taken into emergency surgery. The tumor extended into the pulmonary veins and infiltrated the atrial endocardium, and the histopathologic diagnosis was leiomyosarcoma. The left atrial endocardium was successfully peeled off with the tumor and complete resection was achieved.</p><p><strong>Conclusion:</strong> The possible malignant nature of intracardiac masses should be kept in mind, especially in middle-aged patients. The extent of the tumor must be determined in elective cases to establish the proper strategy for complete resection, which is the only chance of successful treatment for this lethal disease entity. Endocardial peeling is warranted for successful removal of the tumor mass in leiomyosarcoma.</p>

Popliteal artery pseudoaneurysm associated with solitary osteochondromatosis

Osteochondroma is the most common benign tumor of the bone, seen mostly during adolescence. In the current study, we report a 19-year-old male patient with a two-week history of pain and swelling of the medial side of his right thigh just above the knee without any trauma. CT angiography revealed a popliteal artery pseudoaneurysm and its close relationship with a femoral osteochondroma. Surgical repair consisted of repair of pseudoaneurysm and removal of osteochondroma. In young patients, a non-traumatic pseudoaneurysm of distal femoral artery may be a complication of an osteochondroma and this treatable pathology should be looked for to prevent recurrence.

Double-layer pericardial patch for atrial septal defect closure

After repair of atrial septal defects with or without patch, residual shunt, shrinkage, haemolysis and thromboembolic complications may occur. Even though the pericardium is quite a suitable material for the closure of atrial septal defects, the external surface of the pericardium is not smooth and may be a nidus for thrombus formation. We present a new technique to prevent these complications by using a folded, double-layer, durable pericardial patch without chemical pretreatment.

Geometric reconstruction of the sinus of Valsalva: utilization of the porcine aortic root

Surgical repair of ruptured sinus of Valsalva aneurysm can be challenging, although it has been reported that mortality and morbidity is low. Distortion of sinus of Valsalva geometry can cause aortic valve regurgitation immediately or progressively after surgery. Maintenance of the appropriate geometry of sinus of Valsalva after resection of the aneurysm is critical in preserving the native aortic valve and its competency. Successful reconstruction with various patch materials such as Dacron patches (DuPont, Wilmington, DE) or pericardial patches has been reported. Nevertheless, the size and shape of patches used had to be created impromptu by surgeons without reliable methodology of reproducing the precise shape of the naturally occurring sinus of Valsalva. Herein, we report a successful repair of sinus of Valsalva aneurysm by utilizing a porcine sinus of Valsalva from a commercially available Freestyle valve (Medtronic Inc, Minneapolis, MN). We believe that this is a previously unreported technique.

Congenital coronary anomalies and surgical treatment

Coronary artery anomalies are not uncommon, occurring in 1.3% (range = 0.3-5.6%) of the population, and are often an incidental finding in asymptomatic patients. Approximately 20% of coronary anomalies have potential for life-threatening complication, including myocardial infarction, arrhythmia, or sudden death early in life or during adulthood. Coronary artery anomalies are composed of a wide variety of disorders. Some, such as anomalous location of a coronary ostium, duplication of coronary arteries, or multiple ostia, become clinically significant only when another cardiac surgical procedure is necessary, and generally, surgical correction is not required in these patients. On the other hand, the diagnosis of anomalous origin of left coronary artery from pulmonary artery or from the opposite sinus with inter-arterial course is an indication for operation. Some anomalies like coronary artery fistulas, myocardial bridging, and coronary aneurysm require operation only when they cause clinical symptoms. Coronary artery anomalies should be included in the differential diagnosis of anginal symptoms, myocardial infarction, arrhythmia, or heart failure, especially in young patients. Increased awareness of these pathologies will lead to earlier diagnosis and treatment of a potentially life-threatening condition.

Concomitant surgery for renal neoplasm with pulmonary tumor embolism

OBJECTIVE

Gross tumor pulmonary embolism from renal carcinoma is rarely diagnosed preoperatively. Individual cases of intraoperative embolization of tumor during radical resection of the kidney have been reported. We report on 9 patients who underwent pulmonary arterial tumor removal concomitant with nephrectomy.

METHODS

Between 2000 and 2008, 9 patients underwent simultaneous nephrectomy and removal of gross embolic tumor from the pulmonary arteries. In 7 of these patients the diagnosis was made preoperatively by either computed tomography or magnetic resonance imaging. Cardiopulmonary bypass was used in all cases. Bilateral removal of pulmonary artery tumor was required in 7 patients and unilateral in 2.

RESULTS

All patients survived to hospital discharge after a median stay of 8.8 days (mean, 6-17 days). Two patients are currently alive 4 and 56 months after the operation. Six patients died of distant metastasis or local recurrence of disease after 6, 9, 12, 17, 25, and 29 months. Actuarial survival at 6 months, 1, 2, and 3 years was 100%, 75%, 50%, and 25%, respectively.

CONCLUSIONS

Pulmonary artery embolic tumor removal concomitant with nephrectomy for renal carcinoma can be performed safely. Survival of patients with combined surgery is comparable with that of patients with the same stage of renal neoplasm without pulmonary tumor embolism. The pulmonary tumor embolism in patients with renal carcinoma should be considered as extension of vena caval tumor but not as a distant metastasis. Pulmonary tumor removal provides symptomatic relief and may provide a survival benefit in these patients.

Aortic valve replacement in isolated severe aortic stenosis with left ventricular dysfunction: long-term survival and ventricular recovery

OBJECTIVE

The aim of this study was to assess the effects of aortic valve replacement (AVR) on the recovery of left ventricular function and the predictors for long-term survival in patients suffering from isolated severe aortic stenosis (AS) with a significant left ventricular dysfunction (LVD).

METHODS

This retrospective study was conducted on 46 patients with isolated severe AS and LVD [left ventricular ejection fraction (LVEF) = or < 40%] who underwent AVR in our clinic between January 1993 and March 2006. Patients with coronary artery disease, with more than moderate aortic regurgitation (>2), with previous valve replacement or repair, and with other valve pathologies were excluded. The mean aortic valve area was 0.7+/- 0.09 cm2. The following fourteen variables were analyzed: etiology, age (= or >70 years), sex, preoperative New York Heart Association (NYHA) functional class, chronic obstructive pulmonary disease, hypertension, diabetes, peripheral arterial disease, chronic renal insufficiency, need for concomitant procedures for the ascending aorta, cardiopulmonary bypass time = or >120 min, aortic cross-clamp time = or >90 min, intraaortic balloon pump support and inotropic support. Statistical analysis for comparison of pre- and postoperative changes in clinical and functional variables was performed using Wilcoxon rank test. The predictors of early mortality after AVR were analyzed using logistic regression analysis and late survival was studied using Cox proportional regression and Kaplan Meier survival analyses.

RESULTS

Operative mortality was 8.6% with four patients. As the result of univariate logistic regression analysis, preoperative NYHA functional class = or >3 was found to be predictive of early mortality. Patients with NYHA class = or >3 had 12.6 times (OR: 12.6; 95%CI: 1.2-131.3; p=0.035) higher probability of early mortality than those with a lower NYHA class. However, multivariate logistic regression analysis demonstrated no predictor for early mortality. A positive change was observed in the LVEF in 79.3% of survivors and the mean LVEF increased from 34.5+/- 3.9% to 44.7+/- 10.4% (p<0.001). There were eight (19%) late deaths. Actuarial survival was 83. +/- 5.9% at 5 years and 59.6% +/- 10.9% at 10 years. Cox proportional hazards regression analysis demonstrated diabetes mellitus (HR: 6.6; 95% CI: 1.19-36.9, p=0.031) and intraaortic balloon pump use (HR: 10.7; 95% CI: 2.9-39.7, p<0.001) as significant predictors for late mortality.

CONCLUSION

Left ventricular ejection fraction and symptoms improve after AVR in patients with isolated severe AS and LVD with an acceptable operative mortality and satisfactory long-term survival.

Effects of patient-prosthesis mismatch on postoperative early mortality in isolated aortic stenosis

BACKGROUND AND AIM OF THE STUDY

Small valve size and patient-prosthesis mismatch (PPM) generate high postoperative transvalvular gradients and may decrease both early and long-term survival. The study aim was to evaluate whether mismatch affected early mortality after aortic valve replacement (AVR) for isolated aortic stenosis (AS).

METHODS

A total of 701 patients (437 males, 264 females; mean age 53.3 +/- 15.1 years; range: 14-84 years) with pure AS underwent AVR at the authors' institution between 1985 and 2005. The majority of patients (92%) received a mechanical valve. PPM was considered severe if the indexed effective orifice area was < or =0.65 cm2/m2, and moderate if > 0.65 but < or = 0.85 cm2/m2.

RESULTS

Moderate-severe PPM was present in 47% of patients, and severe PPM in 13%. The early mortality was 5.4% (n=38). Multivariate analysis revealed age > or = 70 years (p < 0.001), female gender (p = 0.04) and severe PPM (p = 0.003) as independent predictors of early mortality. Moderate mismatch was not a predictor of early mortality on both univariate and multivariate analysis. Left ventricular dysfunction (ejection fraction < or = 40%) was a risk factor for early mortality only in patients with severe PPM.

CONCLUSION

Patient-prosthesis mismatch should be prevented in patients undergoing AVR for isolated AS, especially in those with left ventricular dysfunction.

Risk Factors for Requirement of Permanent Pacemaker Implantation After Aortic Valve Replacement

BACKGROUND

The aim of this study was to evaluate the frequency of requirement for permanent pacing and related risk factors after aortic valve replacement.

METHODS

Among 465 patients operated between 1994 and 2004, 19(4.1%) patients with a mean age 49.9 +/- 17.2 years required the implantation of a permanent pacemaker. Eleven of them were female (57.9%). The main indication was aortic stenosis (89.5%). Severe annular calcification was documented in 78.9% of them, and the aortic valve was bicuspid in 57.9%.

RESULTS

Risk factors for permanent pacing after aortic valve replacement (AVR) identified by univariate analysis were female sex, hypertension, preoperative ejection fraction, aortic stenosis, annular calcification, bicuspid aorta, presence of right bundle branch block (RBBB) or left bundle branch block (LBBB), prolonged aortic cross-clamp and perfusion times, and preoperative use of calcium channel blockers. Multivariate analysis showed that female sex (p = 0.01, OR; 5.21, 95% CI: 1.48-18.34), annular calcification (p < 0.001, OR; 0.05, 95% CI: 0.01-0.24), bicuspid aortic valve (p = 0.02, OR; 0.24, 95% CI: 0.07-0.84), presence of RBBB (p = 0.009, OR; 0.03, 95% CI: 0.003-0.44) or LBBB (p = 0.01, OR; 0.13, 95% CI: 0.02-0.69), hypertension (p = 0.03, OR; 0.22, 95%CI: 0.05-0.89), and total perfusion time (p = 0.002, OR; 1.05, 95% CI: 1.01-1.08) were associated risk factors.

CONCLUSION

Irreversible atrioventricular block requiring a permanent pacemaker implantation is an uncommon complication after AVR. Risk factors are annular calcification, bicuspid aorta, female sex, presence of RBBB or LBBB, prolonged total perfusion time, and hypertension.

Melatonin protects against ischemia/reperfusion injury in skeletal muscle

Melatonin has been shown to diminish ischemia-reperfusion (I/R) injury in many tissues. The main aim of this study was to evaluate the protective antioxidant effect of melatonin in skeletal muscle during I/R injury. Wistar albino rats were randomly divided into three groups. Hindlimb ischemia was achieved by clamping the common femoral artery in two groups but not in control group. Limbs were rendered ischemic for 1.5 hr; at the end of the reperfusion period of 1.5 hr muscle tissue samples were taken for the histological evaluation and biochemical analysis. Melatonin (10 mg/kg) was injected i.p. in the I/R + Mel group at the onset of ischemia whereas the vehicle solution was injected in the I/R group. In I/R + Mel group histological damage was significantly less than in the I/R group (P < 0.001). In the I/R + Mel group, the mean malonedialdehyde level was lower than in the I/R group (P < 0.01) and was quite near to the levels in the control group (P > 0.05). Glutathione levels were found to be reduced in the I/R group compared with the control (P < 0.01) and I/R + Mel group (P < 0.01). Melatonin has a protective effect against I/R injury in skeletal muscle and may reduce the incidence of compartment syndrome, especially after acute or chronic peripheral arterial occlusions.

Reversed-J inferior versus full median sternotomy: which is better for awake coronary bypass surgery

BACKGROUND

The aim of this study was to ascertain whether the approach with a less invasive reversed-J inferior sternotomy could improve intraoperative patient compliance and postoperative recovery than the standard median sternotomy.

METHODS

Seventeen patients underwent elective single coronary artery bypass graft operation under high thoracic epidural anesthesia without endotracheal intubation. The reversed-J sternotomy was performed in 10 patients (Group A) and full sternotomy in 7 patients (Group B). The technical and surgical difficulties, pulmonary functions (by spirometric tests) and hospital stay were assessed.

RESULTS

Through the reversed-J sternotomy coronary revascularization was accomplished without any additional technical difficulties and with a good exposure of both the left anterior descending artery and the left internal thoracic artery. No conversion to standard sternotomy and no intubation were observed. Additional doses of local anesthetic at jugular notch was not required in Group A. Pleura was opened more in Group B (57% vs. 20%; p = 0.14). Oxygen saturation was better in Group A during the surgical procedure (98.8 +/- 0.7% vs. 97.1 +/- 2.1%; p = 0.033), however, intraoperative PaCO2 was similar in both the groups. The patients in Group A were discharged from the hospital earlier (3.2 +/- 1.5 vs. 7.3 +/- 3.5 days; p = 0.004).

CONCLUSIONS

Less invasive approach to coronary artery bypass graft operations is possible through combination of the high thoracic epidural anesthesia and a reversed-J sternotomy. This technique is less traumatic for patient and provides practical better oxygenation and shorter hospital stay.

Long-Term Outcome After Total Correction of Tetralogy of Fallot in Adolescent and Adult Age

Although most patients with tetralogy of Fallot (TOF) undergo radical repair during infancy and childhood, patients remaining undiagnosed and untreated until adulthood can still be treated. These patients have either a previous palliative or natural collateral circulation to the lung or a mild form of right ventricular outflow tract (RVOT) obstruction. The aim of this study is to analyze the perioperative and long-term results of radical corrective procedures in patients who reached adult ages. Two hundred and seven patients with TOF underwent complete correction between 1985-and 2002, 64 (30.9%) of whom were aged 14 years or more. The mean age at corrective repair for this group was 20.6 +/- 7.5 years (range 14 to 49 years). Only two patients had previous modified Blalock-Taussig shunts. In 44 patients (68.7%) besides infundibular resection, a transannular gluteraldehyde-treated pericardial patch was used to reconstruct right ventricular outflow tract (RVOT). Only infundibular patching was used in 15 patients (23.4%) and infundibular muscular resection with primary closure of right ventricle was performed in five patients (7.8%). Hospital mortality was 3.1% with two patients. Four patients (6.2%) underwent reoperation because of recurrent ventricular septal defect (VSD) with/without residual obstruction or pulmonary regurgitation. All survivors were in NYHA class I (42) or II (17). Late mortality was recorded in two patients and 16-year actuarial survival was 89.2%+/- 4.9%. The significant negative predictors of late survival determined by univariate analysis were reoperation <0.018) and associated cardiac anomalies <0.011). Multivariate analysis showed that there was no negative predictor of late-term mortality. Corrective procedures in adult patients with TOF can be performed successfully compared to patients who underwent operation during infancy and childhood.

Surgery for Chronic Total Occlusion of the Left Main Coronary Artery- Myocardial Preservation

We report seven patients with chronic total occlusion of the left main coronary artery that were operated in our institution and discuss the myocardial preservation options in these patients. In addition to total occlusion of the left main coronary artery, three patients also had severe lesions of right coronary artery. Prior myocardial infarction history and significantly depressed left ventricle functions were detected in all three patients with right coronary artery lesions. Five patients were operated on cardiopulmonary bypass while two patients were operated off pump. All patients received alternating antegrade/retrograde cardioplegia for myocardial preservation. In patients with simultaneous right coronary artery disease we first established the origin of the collaterals to the left coronary system. For patients with collaterals arising from the right coronary artery segment distal to the right coronary artery lesion, the antegrade component was administered through the saphenous vein graft bypassed to a distal part of right coronary artery segment. Thus we have achieved a more effective distribution of the antegrade cardioplegia. In off-pump-operated patients the left coronary system was revascularized before the right coronary system. Postoperative low cardiac output syndrome occurred in only one patient who was operated off pump. There was no operative and early mortality. Mean follow-up was 32 +/- 21.42 (range, 4 to 60) months. Alternating antegrade/retrograde cardioplegia was used with acceptable results in patients with total occlusion of the left main coronary artery. In patients with simultaneous RCA lesion we recommend regulation of the antegrade component based on the origin of collaterals that supplies the left coronary system. In off-pump-operated patients we suggest avoiding of clamping of right coronary artery at the beginning of the operation while it still supplies all the coronary circulation.

Off-Pump Awake Coronary Revascularization Using Bilateral Internal Thoracic Arteries

BACKGROUND

A new technique has been developed that permits complete arterial revascularization of the lateral and/or inferior wall of the heart using in situ bilateral internal thoracic artery grafts in awake patients. This technique, without cardiopulmonary bypass and mechanical ventilation, creates the least invasive revascularization method for the lateral and/or posterior wall of the heart yet described.

METHODS

In 7 patients double or triple vessel coronary artery bypass grafting was performed without general anesthesia. A high thoracic epidural anesthesia was started one hour before surgery. Bilateral internal thoracic arteries were harvested and all anastomoses were performed with the off-pump technique by standard median sternotomy. Circumflex, or the right coronary artery, were anastomosed with bilateral internal thoracic arteries using a heart positioner. Six patients received double bypass grafting and one patient received triple bypass grafts (bilateral internal thoracic arteries and one radial artery).

RESULTS

All patients remained awake throughout the whole procedure. There was no perioperative myocardial infarction or mortality. Pneumothorax was observed in three patients, but it was repaired in two. Only one patient completed the procedure with unilateral pneumothorax. There were no hemodynamic and pulmonary problems during lateral or posterior wall revascularization. Two patients required unexpected coronary endarterectomy during circumflex and right coronary artery anastomoses.

CONCLUSIONS

Complete arterial revascularization by median sternotomy using in situ bilateral internal thoracic artery grafts without general anesthesia is a feasible and safe procedure for multivessel disease. This approach gives a chance for awake revascularization of the right and/or circumflex coronary artery.

Combined coronary artery bypass grafting and lung surgery

Combined coronary bypass and lung surgery was performed in 3 patients. Through a median sternotomy or a left thoracotomy, bypass grafting was performed on beating heart or under cardiopulmonary bypass, followed by the lung operation. The lung lesion was diagnosed as carcinoma in 2 patients and hydatid cyst in 1 patient. With few exceptions, beating heart coronary bypass through a median sternotomy can be performed in a combined operation.

Complete off-pump coronary revascularization in patients with dialysis-dependent renal disease

Patients who have dialysis-dependent renal disease frequently present with coronary artery disease but are considered at high risk for coronary artery bypass grafting. From 1 September 2000 through 31 August 2003, we performed complete off-pump coronary revascularization in 6 patients who had end-stage dialysis-dependent renal failure, and we prospectively studied the perioperative and early postoperative results. The effect of off-pump coronary artery bypass grafting on mortality, morbidity, postoperative complications, and transfusion requirements in this group of patients was investigated. No perioperative deaths or ischemic cardiac events were observed after off-pump coronary artery bypass grafting. In all patients, anginal symptoms were relieved during the postoperative period. The mean duration of follow-up was 172 +/- 12.4 months. Patients with dialysis-dependent chronic renal failure who present with coronary artery disease should be thoroughly evaluated preoperatively for risk factors and coexistent severe diseases. We believe that in patients with end-stage dialysis-dependent chronic renal failure, off-pump coronary revascularization is a good alternative.

Markers of myocardial ischemia in the evaluation of the effect of left anterior descending coronary artery lesion and collateral circulation on myocardial injury in 1-vessel off-pump coronary bypass surgery

BACKGROUND

The purpose of this study was to use serum markers for myocardial tissue damage to evaluate the effect of the severity of left anterior descending artery (LAD) lesions after 1-vessel off-pump coronary artery bypass grafting.

METHODS

A consecutive series of 20 patients with a totally occluded LAD and only retrograde filling (group T; n = 10) or critical stenosis (70%-99%) and only antegrade filling (group C; n = 10) were included in this study. One patient in group C who displayed no increases in the levels of markers for myocardial ischemia was excluded from the study because of the intraoperative repetition of the anastomosis. Creatine kinase activity (CK), CK-MB activity, and CK-MB mass, myoglobin, lactate, and cardiac troponin I (cTnI) concentrations were determined in venous blood samples taken immediately before and after the anastomosis and at 4, 8, 12, 24, and 48 hours postoperatively.

RESULTS

There were no perioperative myocardial infarctions. One patient in group T developed low cardiac output syndrome 48 hours after the operation and died after 1 month. His enzyme levels did not increase in the first 2 days postoperatively. Anastomosis times were similar for the T and C groups (6.85 +/- 0.9 minutes versus 8.4 +/- 2.2 minutes, respectively; P =.069). The levels of all cardiac markers except cTnI increased significantly in the first 24 postoperative hours. CK-MB activity, CK-MB mass concentration, and cTnI concentration were not different between the 2 groups. Four patients in each group were evaluated for the patency of the anastomosis, and all control angiography and myocardial scanning tests showed patent anastomoses and no ischemia.

CONCLUSIONS

One-vessel off-pump coronary artery bypass grafting can be performed safely in patients with serious LAD stenosis and borderline antegrade blood flow without the need for any coronary collateral circulation support. A short anastomosis time prevents myocardial injury during off-pump coronary surgery.