Clinical autologous in vitro endothelialization of 153 infrainguinal ePTFE grafts.

BACKGROUND: Over the past 17 years, our group has developed and clinically applied an in vitro endothelialization procedure whereby infrainguinal expanded polytetrafluoroethylene (ePTFE) prostheses are confluently lined with cultured autologous endothelial cells before implantation. After a successful randomized pilot study from 1989 to 1993, the procedure was adopted for routine operations. METHODS: Since June 1993, 153 endothelialized ePTFE grafts were implanted in the infrainguinal position in 136 patients (102 above knee (AK) and 51 below knee (BK), 89 men and 47 women, mean age 64.7+/-9.4 years). Seventeen patients received an endothelialized prosthesis bilaterally. Autologous endothelial cells were harvested from 4- to 5-cm segments of a subcutaneous vein (in 86% the cephalic vein), grown to first-passage mass cultures and confluently lined onto 6- (n = 113) or 7-mm (n = 40) inner diameter (ID) ePTFE grafts, precoated with fibrin glue. The observation period for 6-mm grafts was 7 years, and for 7-mm grafts was 4 years. Patency assessment for Kaplan-Meier survivorship analyses was based on duplex sonography and angiography. RESULTS: Kaplan-Meier survivorship function revealed a primary patency rate of 62.8% after 7 years (SE = 0.05) for all infrainguinal reconstructions (60% AK/70.8% BK). The primary patency for stage II and III patients was 64.4% after 7 years. The more recent group of 7-mm ID grafts showed a primary patency of 83.7% after 4 years. CONCLUSIONS: Our data provide strong evidence that autologous endothelial cell lining distinctly improves the patency of small diameter vascular grafts.

The bridge graft: a new concept for infrapopliteal surgery.

BACKGROUND: The long-term results of ePTFE grafts are particularly poor in crural reconstructions. We report on a novel surgical technique, whereby both run-off and anastomotic mismatches are concomitantly addressed. PATIENTS AND METHODS: Short segments of vein grafts (5-15 cm in length) were used to bridge two crural artery segments. Subsequently, a femoro-distal ePTFE graft was anastomosed to the bridge graft. Venous valves were made incompetent to allow bi-directional flow. In a retrospective series of 45 patients with crural bridge grafts, 12 patients were in stage III and 33 in stage IV. In 18 patients the reconstruction was the first procedure and in the remaining 28 patients it was the first or second re-operation. RESULTS: The primary patency rate at 1, 2, 3 and 4 years was 53, 44, 35 and 26% respectively. The secondary patency rate was 67, 53, 49 and 39% respectively. The corresponding limb salvage rate was 70, 61, 56 and 45%. In a small subgroup of patients, in which the crural bridge was the first reconstructive procedure, the primary patency was 76 at 1 year and 64 at 4 years. CONCLUSION: convincing long-term crural bridge grafts should be considered in those patients who have more than one crural or pedal artery available for grafting and an insufficient length of saphenous vein.

Crystalloid versus blood cardioplegia in coronary by-pass surgery. A prospective, randomized, controlled study in 100 consecutive adults.

In a prospective randomized trial we investigated the benefit of blood versus asanguinous cardioplegia in routine coronary by-pass grafting. One hundred consecutive adult patients were randomly assigned to two groups: Group A (53 patients) received cold blood cardioplegia and group B (47 patients) had standard St. Thomas solution. In all patients we combined ante- and retrograde administration, in group A warm reperfusion was carried out before aortic declamping. Aortic cross clamp times, amount of cardioplegic solution and blood potassium levels at the end of cardio-pulmonary by-pass were higher in group A than in group B. The need for inotropic support at the end of the operation as well as in the postoperative period was more frequent in the crystalloid cardioplegia group. The occurrence of atrial fibrillation showed no clear correlation to the kind of cardioplegia used. Perioperative infarction was less frequent in the blood cardioplegia group (3.7% vs 6.3%; p < 0.01) and 30-day-mortality was nil (0% vs 3.2%; p < 0.01). Hospital stay did not differ between the two groups. In this clinical trial we could demonstrate the superiority of blood versus crystalloid cardioplegia in routine coronary by-pass grafting. Ante- and retrograde delivery of cold blood cardioplegia followed by warm reperfusion is a safe and simple method yielding satisfactory results.