[Dacron and polytetrafluoroethylene aorto-bifemoral grafts].

INTRODUCTION

In reconstructive procedures of the abdominal aorta synthetic grafts are today mostly used. There are two types of bifurcated synthetic grafts: Dacron and polytetrafluorethilene (PTFE). In many papers these grafts are compared in aortobifemoral position. Karner 1988, and Lord 1988, found no significant difference between them after aortobifemoral reconstructions. In 1955. Paaske wrote about a new "stretch" bifurcated PTFE graft in aortobifemoral position. Comparing this material with standard Dacron graft, he only found a shorter operating time. The aim of this paper is to compare Dacron and PTFE bifurcated grafts in aortobifemoral position in patients with aortoiliac occlusive diseases.

MATERIAL AND METHODS

This prospective study included 283 aortobifemoral reconstructions due to aortoiliac occlusive diseases operated between January 1st, 1984 and December 31st, 1992 at the Institute for Cardiovascular Diseases of the Serbian Clinical Centre in Belgrade. Bifurcated PTFE grafts were used in 136 patients, and nonimpregnated knitted Dacron grafts in 147 subjects. There were 25 (8.8%) female and 258 (91.2%) male patients, average age 56.88 years. Ninety one (32.2%) patients had a claudication discomfort (Fonten stadium II), 91 (32.2%) disabling claudication discomfort (Fonten stadium IIB), 45 (15.9%) rest pain (Fonten stadium III), and 56 (19.8%) gangrene (Fonten stadium IV). In 45 (15.9%) patients previous vascular procedures were performed. Prior to operation, Doppler ultrasonography and translumbar aortography were carried out (Figure 1). Transperitoneal approach to abdominal aorta, and standard inguinal approach to femoral arteries were used. In 154 (54.4%) patients proximal anastomosis had an end to side (TL), and in 129 (45.6%) end to end (TT) form. In 152 (26.88%) cases distal anastomosis was done in the common femoral (AFC) artery, and in 414 (73.2%) cases in the deep femoral (APF) artery. In 7 patients the aorto-femoro-popliteal "jumping" bypass was done, and in 29 patients simultaneous sequential femoro-popliteal bypass graft. The patients were following-up over the period from one, six and twelve months after operation, and later once a year, using physical examination and Doppler ultrasonography. In patients with suspected graft occlusion, anastomotic stenosis, pseudoaneurysms, progression of distal arterial diseases, Duplex ultrasonography and angiography were also used, and leukoscintigraphy in patients with suspected infection. Statistical analysis was performed using Long Rank and Student t-test.

RESULTS

Inhospital mortality rate was 11 (7%). Distal reconstructions significantly increased the mortality rate when simultaneously performed with aortobifemoral bypass graft (p < 0.01). The follow-up period was from 2 months to 9.5 years (mean 3.6 years). The early patency rate was 97% from PTFE and 99.4% for Dacron grafts, while the late patency rate was 94.9% for PTFE and 96.6% for Dacron grafts. The type of the graft had no statistical influence on the early and late graft patency (p > 0.05) (Graphs 1, 2, 3). Six (2.1%) early unilateral limb occlusions were observed. Five patients had the PTFE and one the Dacron graft, without statistically significant difference (p > 0.05). The reasons for early graft occlusion were: stenosis of distal anastomosis in 3 patients, and pure run off in 3 patients. In 5 patients urgent reoperation (limb thrombectomy with profundoplasty or femoro-popliteal bypass graft above the knee) were done with complete recovery of legs. However, in one patient the above knee amputation was done. During the follow-up period, 14 (5.2%) late graft occlusions were recorded. There were 11 unilateral limb occlusions and 3 bilateral. All patients with bilateral occlusions had PTFE grafts but this was not statistically significant (p > 0.05) comparing two types of grafts. Taking into account all late occlusions, there were 7 PTFE and 7 Dacron grafts. There was no statistical difference betwe