Transobturator Bypass Utilizing Fluoroscopic Guidance

Introduction

Transobturator bypass is an older and less frequently performed revascularization of the lower extremity that is useful in the setting of multiple failed lower extremity bypasses usually due to groin sepsis and infection(s). It can be a technically challenging operation due to anatomic constraints.

Report

We describe a successful transobturator bypass utilizing fluoroscopy for passage of bypass tunneler and graft through the obturator foramen.

Discussion

Live fluoroscopy is a versatile technique and in conjunction with our described surgical technique of lower extremity bypass should help increase the technical success rates of this procedure.

Thoracoscopic excision of mediastinal bronchogenic cysts: results in 20 cases

BACKGROUND

We present our experience with thoracoscopic resection of mediastinal bronchogenic cysts in adults.

METHODS

From November 1990 to September 1993, 20 patients with mediastinal bronchogenic cysts were operated on by thoracoscopy. The average cyst size was 4.9 cm, and the largest diameter was 10 cm. Ten cysts were located in the middle mediastinum and 10 in the posterior mediastinum. Two cysts were complicated.

RESULTS

Thirteen bronchogenic cysts were resected completely by thoracoscopy. We had to convert thoracoscopy into thoracotomy because of bleeding in two cases and because of major adhesions to vital structures in five cases. There were no operative deaths and no postoperative complications. Mean hospital stay was significantly less in the completely thoracoscopically treated group. Long-term follow-up (range, 4.5 to 7.5 years) showed no late complications and no recurrence.

CONCLUSIONS

Preoperative complications, intraoperative injuries, and major adhesions to vital structures seem to be the only unfavorable conditions to thoracoscopic treatment of bronchogenic cysts. This study found encouraging results for thoracoscopic excision of mediastinal bronchogenic cysts in selected patients.

Infrared spectroscopy in the evaluation of the process of calcification of valvular bioprostheses

BACKGROUND

The methods currently used to analyze the process of calcification of bioprostheses give only global information on calcium deposition. We investigated the potential advantage of infrared spectroscopy, which makes it possible to analyze the various components of the calcification process, ie, lipids, proteins, and calcium deposits.

METHODS

Sixty porcine aortic leaflets were fixed in 0.6% glutaraldehyde and then subsequently implanted in 10-day-old Wistar rats. The valve leaflets were removed 2, 7, 14, 21, 35, and 56 days after implantation.

RESULTS

Before implantation infrared spectroscopic analysis revealed the presence of proteins only. On day 2 after implantation, all valves showed minor lipid deposits. On day 7, amorphous calcium phosphate was detected. Between days 7 and 14, crystalline forms of calcium phosphate appeared and amorphous calcium phosphate progressively changed into carbapatite over the 56-day period.

CONCLUSIONS

Infrared spectroscopy yields valuable additional information on the nature and kinetics of the various components of glutaraldehyde-treated tissues after implantation. It may prove to be important in the evaluation of new techniques of calcium mitigation.

Does glutaraldehyde induce calcification of bioprosthetic tissues?

BACKGROUND

Glutaraldehyde has been said to be responsible in part for the calcification of glutaraldehyde-treated tissues after implantation in animals or humans. We investigated whether the origin of the tissue, autologous or heterologous, could have a more prominent role in the process of calcification.

METHODS

Three-month-old sheep received sheep pericardial samples (n = 133) and human pericardial samples (n = 123) implanted subcutaneously. Samples were treated with 0.6% glutaraldehyde for 5, 10, or 20 minutes or 7 days and then rinsed thoroughly before implantation. Samples were then retrieved after 3 months. Calcium content was assessed by spectrophometry.

RESULTS

The results show a low calcium content in the autologous group (mean 1.14+/-2.07) and a high calcium content in the heterologous group (mean 38.97+/-26). These results were the same regardless of the duration of the treatment.

CONCLUSIONS

Glutaraldehyde treatment (0.6%) does not play a significant role in the calcification of glutaraldehyde-treated tissue regardless of the origin, autologous or heterologous, of the tissue. Glutaraldehyde-treated autologous tissues are associated with an incidence of calcification lower than heterologous tissues.

Videothoracoscopic lung biopsy in diffuse infiltrative lung diseases: a 5-year surgical experience

BACKGROUND

To establish an accurate diagnosis of diffuse infiltrative lung disease, a surgical lung biopsy may be required. We report our experience with video-thoracoscopic lung biopsy over a period of 5 years.

METHODS

From March 1992 through December 1996, videothoracoscopic lung biopsy was performed in 64 patients (17 were women [26.5%]; age, 50.5+/-13 years) with a diagnosis of diffuse infiltrative lung disease of an unknown cause. All patients except one received general anesthesia. Single lung ventilation was used in 61 patients. All lung biopsies were obtained with an endoscopic stapler.

RESULTS

Single lung biopsies were performed in 39 patients (61%), two biopsies in 23 patients (36%), and three biopsies in 2 patients. Minithoracotomies were necessary in 10 patients (15.6%) owing to an iatrogenic pulmonary wound (1 patient), extensive pleural adhesions (6 patients), and a stiff lung (3 patients). Postoperative complications were rare and included five discrete pneumothoraces (7.8%), all resolving spontaneously, one prolonged air leak (1.6%), and one hemothorax requiring reoperation. Three preoperatively debilitated patients died (4.7%), 2 with progression of respiratory failure and 1 owing to septic shock. Average chest tube duration was 2.4+/-2 days and average hospital stay was 4.6+/-2.5 days. Lung biopsy contributed to the diagnosis in 59 patients (92%).

CONCLUSIONS

Videothoracoscopic lung biopsy using an endoscopic stapler is a safe and effective procedure in most cases and should be performed by trained thoracic surgeons.

Surgical management of mitral regurgitation associated with Marfan's syndrome

BACKGROUND

The surgical treatment of mitral regurgitation associated with Marfan's syndrome remains controversial because of the underlying degenerative process.

METHODS

From October 1986 to June 1996, 33 patients with Marfan's syndrome underwent a mitral valve procedure. The mean age was 30 years (range, 2 to 55 years). Mitral regurgitation was caused by annulus dilatation in 2 patients, leaflet prolapse in 30 patients, and restricted leaflet motion in 1 patient. Mitral valve repair was performed in all patients except 1 who had mitral valve replacement.

RESULTS

Two patients died in the perioperative period. All survivors were available for follow-up, which ranged from 1 month to 122 months (mean follow-up, 39 months). There were three late deaths, two of which were related to aortic complications. The actuarial survival rate was 78.9% at 10 years. Freedom from mitral valve reoperation was 87.1% at 10 years. Echocardiographic studies were obtained in all survivors and showed absent or mild (1+) mitral regurgitation in 21 patients and moderate (2+) mitral regurgitation in 3.

CONCLUSIONS

Mitral valve repair for mitral regurgitation in patients with Marfan's syndrome can be performed safely in almost all instances. This technique provided stable midterm results comparable with those obtained for other degenerative mitral valve diseases.

Comparison of cold versus warm cardioplegia. Crystalloid antegrade or retrograde blood?

BACKGROUND

To evaluate the efficacy of warm versus cold and antegrade versus retrograde cardioplegia, 163 patients were randomized in sequence in three groups and underwent isolated coronary artery bypasses (mean, 4 grafts/patients) alternating in sequence.

METHODS AND RESULTS

The demographic profiles were identical. Cold crystalloid cardioplegia (group 1) was delivered through the aortic root intermittently. The warm retrograde (group 2) was started antegrade with high potassium solution until the heart stopped. It was continued with retrograde coronary sinus perfusion, 100 mL/min of warm blood. Cold retrograde blood cardioplegia (4:1) (group 3) was started antegrade and continued retrograde through the coronary sinus. The heart temperature was kept at 10 degrees to 15 degrees C. Patients were evaluated intraoperatively and postoperatively for (1) supraventricular tachycardia, (2) ECG changes, (3) lactate dehydrogenase and total CPK and isoenzyme (MB) studies, and (4) hemodynamic studies in the intensive care unit. Warm retrograde and cold retrograde patients had sampling of the ascending aorta (antegrade) and the coronary sinus (retrograde) measuring pH, A-VO2 differences, and CK enzyme leak.

RESULTS

The incidence of supraventricular tachycardia was 29% in group 2, 22% in group 1, 18% in group 3; not significant (NS). CPK isoenzyme MB fraction showed identical levels (NS). The warm heart consumed 1.3 to 1.6 mL O2/100 mL flow, while the cold group 3 showed 0.5 to 0.6 mL O2/100 mL flow (P < .001). Cold crystalloid cardioplegia (group 1) was similar to group 3 (0.3 mL O2/100 mL). All three groups were similar hemodynamically (cardiac output, cardiac index, left ventricular stroke work index). Two of 163 patients died in group 2. Four sustained stroke, three in group 2, one with a fatal outcome.

CONCLUSIONS

Continuous warm cardioplegia (group 2) did not provide better myocardial protection despite that no CK-MB isoenzyme leak was demonstrated intraoperatively. Intermittent cold crystalloid cardioplegia and cold retrograde provided a clearer operative field and motionless heart. As long as O2 was adequately supplied, under 90 minutes' cross-clamp time, cold crystalloid cardioplegia and cold retrograde blood cardioplegia is safe under hypothermic conditions, whereas warm cardioplegia requires continuous uninterrupted technique with oxygen delivery.

Oxypurinol protects normothermic ischemic hearts

Rabbit hearts were mounted on a Langendorff apparatus and after measurement of baseline hemodynamic function exposed to 30 minutes normothermic arrest. Hearts were reperfused at 37 degrees C with buffer solution containing oxypurinol in different concentration: group II (0.01 mM), group III (0.1 mM), group IV (1 mM). Group I did not receive active drug and served as control. Each group consisted of eight hearts. After reperfusion, hemodynamic function was again measured and compared to baseline. Groups III and IV showed significantly less deterioration (p less than 0.05) than the control, while group II was better than the control, but in general differences were nonsignificant. We conclude that oxypurinol ameliorates ischemic cardiac damage following normothermic cardiac arrest. The beneficial effect of oxypurinol is most likely due to the drug's scavenging effect of oxygen-free radicals.