Chirurgie Aortique - Aortic Surgery

Etudes sur les petits anévrismes - Small aneurysm trials:

1. Lederle, F. A., G. R. Johnson, et al. (2003). "Quality of life, impotence, and activity level in a randomized trial of immediate repair versus surveillance of small abdominal aortic aneurysm." J Vasc Surg 38(4): 745-52.
OBJECTIVE: We compared long-term health-related quality-of-life outcome after randomization to immediate elective repair or imaging surveillance, and in relation to time of elective repair, in patients with small asymptomatic abdominal aortic aneurysm (AAA). METHODS: This randomized clinical trial was carried out in 16 Veterans Affairs medical centers. Study subjects were patients at good surgical risk, aged 50 to 79 years, with AAAs 4.0 to 5.4 cm in diameter. Interventions included immediate open surgical AAA repair or imaging surveillance every 6 months with repair reserved for AAAs that became symptomatic or enlarged to 5.5 cm. Main outcome measures considered were SF-36 health status questionnaire, prevalence of impotence, and maximum activity level, which were determined at randomization and at all follow-up visits. RESULTS: Eleven hundred thirty-six patients were randomized and followed up for 3.5 to 8 years (mean, 4.9 years). The two randomized groups did not differ significantly for most SF-36 scales at most times, but the immediate repair group scored higher overall in general health (P <.0001), which was particularly evident in the first 2 years after randomization, and slightly lower in vitality (P <.05). The baseline value of one SF-36 scale, physical functioning, was an independent predictor of mortality. Overall, more patients became impotent after randomization to immediate repair compared with surveillance (P <.03), but this difference did not become apparent until more than 1 year after randomization. Maximum activity level did not differ significantly between the two randomized groups, but decline over time was significantly greater in the immediate repair group (P <.02). CONCLUSIONS: For most quality-of-life measures and times there was no difference between randomized groups. Immediate repair resulted in a higher prevalence of impotence more than 1 year after randomization, but was also associated with improved perception of general health in the first 2 years.

2. Lederle, F. A., S. E. Wilson, et al. (2002). "Immediate repair compared with surveillance of small abdominal aortic aneurysms." N Engl J Med 346(19): 1437-44.
BACKGROUND: Whether elective surgical repair of small abdominal aortic aneurysms improves survival remains controversial. METHODS: We randomly assigned patients 50 to 79 years old with abdominal aortic aneurysms of 4.0 to 5.4 cm in diameter who did not have high surgical risk to undergo immediate open surgical repair of the aneurysm or to undergo surveillance by means of ultrasonography or computed tomography every six months with repair reserved for aneurysms that became symptomatic or enlarged to 5.5 cm. Follow-up ranged from 3.5 to 8.0 years (mean, 4.9). RESULTS: A total of 569 patients were randomly assigned to immediate repair and 567 to surveillance. By the end of the study, aneurysm repair had been performed in 92.6 percent of the patients in the immediate-repair group and 61.6 percent of those in the surveillance group. The rate of death from any cause, the primary outcome, was not significantly different in the two groups (relative risk in the immediate-repair group as compared with the surveillance group, 1.21; 95 percent confidence interval, 0.95 to 1.54). Trends in survival did not favor immediate repair in any of the prespecified subgroups defined by age or diameter of aneurysm at entry. These findings were obtained despite a low total operative mortality of 2.7 percent in the immediate-repair group. There was also no reduction in the rate of death related to abdominal aortic aneurysm in the immediate-repair group (3.0 percent) as compared with the surveillance group (2.6 percent). Eleven patients in the surveillance group had rupture of abdominal aortic aneurysms (0.6 percent per year), resulting in seven deaths. The rate of hospitalization related to abdominal aortic aneurysm was 39 percent lower in the surveillance group. CONCLUSIONS: Survival is not improved by elective repair of abdominal aortic aneurysms smaller than 5.5 cm, even when operative mortality is low.

3. Lederle, F. A., G. R. Johnson, et al. (2000). "Yield of repeated screening for abdominal aortic aneurysm after a 4-year interval. Aneurysm Detection and Management Veterans Affairs Cooperative Study Investigators." Arch Intern Med 160(8): 1117-21.
BACKGROUND: Little is known about the rate at which new abdominal aortic aneurysms (AAAs) develop or whether screening older men for AAA, if undertaken, should be limited to once in a lifetime or repeated at intervals. METHODS: A large population of veterans, aged 50 through 79 years, completed a questionnaire and underwent ultrasound screening for AAA. Of these, 5151 without AAA on the initial ultrasound (defined as infrarenal aortic diameter of 3.0 cm or larger) were selected randomly to be invited for a second ultrasound screening after an interval of 4 years. Local records and national databases were searched to identify deaths and AAA diagnoses made during the study interval in subjects who did not attend the rescreening. RESULTS: Of the 5151 subjects selected for a second screening, 598 (11.6%) had died (none due to AAA), and 20 (0.4%) had an interim diagnosis of AAA. A second screening was performed on 2622 (50.9%), of whom 58 (2.2%; 95% confidence interval, 1.6%-2.8%) had new AAA. Three new AAAs were 4.0 to 4.9 cm, 10 were 3.5 to 3.9 cm, and 45 were 3.0 to 3.4 cm. Independent predictors of new AAA at the second screening included current smoker (odds ratio, 3.09; 95% confidence, 1.74-5.50), coronary artery disease (odds ratio, 1.81; 95% confidence interval, 1.07-3.07), and, in a separate model using a composite variable, any atherosclerosis (odds ratio, 1.97; 95% confidence interval, 1.16-3.35). Adding the interim and rescreening diagnosis rates suggests a 4-year incidence rate of 2.6%. Rescreening only in subjects with infrarenal aortic diameter of 2.5 cm or greater on the initial ultrasound would have missed more than two thirds of the new AAAs. CONCLUSIONS: A second screening is of little practical value after 4 years, mainly because the AAAs detected are small. However, the incidence that we observed suggests that a second screening after longer intervals (ie, more than 8 years) may provide yields similar to those seen in initial screening and therefore warrants further study.

4. (1998). "Length of hospital stay following elective abdominal aortic aneurysm repair. U.K. Small Aneurysm Trial Participants." Eur J Vasc Endovasc Surg 16(3): 185-91.
OBJECTIVES: To investigate factors associated with a prolonged hospital stay after elective open surgical repair of abdominal aortic aneurysm. PATIENTS AND METHODS: We have investigated prospectively base-line risk factors associated with an increased length of postoperative hospital stay in 474 of the patients undergoing surgery as part of the U.K. Small Aneurysm Trial. RESULTS: The median length of hospital stay was 11 days (interquartile range 9-14 days). Age (within the range 60-76 years), sex body mass index, aneurysm diameter, graft type (tube or bifurcated), hospital (university or other), ECG characteristics, angina (from Rose questionnaire) and/or previous myocardial infarction were not associated with length of hospital stay. Quality of life also was assessed before surgery using the Medical Outcomes Study SF20. Psychosocial aspects including level of social functioning, role functioning, mental health, health perceptions and pain were not associated with length of postoperative stay. The level of preoperative physical functioning was associated inversely with length of hospital stay, p = 0.004. Patients' length of hospital stay also was inversely associated with preoperative lung function: FEV1, p = 0.011 and FVC, p = 0.006. In contrast, smoking habit was of only borderline significance, p = 0.09. CONCLUSION: Conditional logistic regression analysis identified only preoperative lung function (FEV1 and FVC) and physical functioning, three intrinsically linked factors, as predictors of length of hospital stay after elective repair of an abdominal aortic aneurysm.

5. (1998). "Mortality results for randomised controlled trial of early elective surgery or ultrasonographic surveillance for small abdominal aortic aneurysms. The UK Small Aneurysm Trial Participants." Lancet 352(9141): 1649-55.
BACKGROUND: Early elective surgery may prevent rupture of abdominal aortic aneurysms, but mortality is 5-6%. The risk of rupture seems to be low for aneurysms smaller than 5 cm. We investigated whether prophylactic open surgery decreased long-term mortality risks for small aneurysms. METHODS: We randomly assigned 1090 patients aged 60-76 years, with symptomless abdominal aortic aneurysms 4.0-5.5 cm in diameter to undergo early elective open surgery (n=563) or ultrasonographic surveillance (n=527). Patients were followed up for a mean of 4.6 years. If the diameter of aneurysms in the surveillance group exceeded 5.5 cm, surgical repair was recommended. The primary endpoint was death. Mortality analyses were done by intention to treat. FINDINGS: The two groups had similar cardiovascular risk factors at baseline. 93% of patients adhered to the assigned treatment. 309 patients died during follow-up. The overall hazard ratio for all-cause mortality in the early-surgery group compared with the surveillance group was 0.94 (95% CI 0.75-1.17, p=0.56). The 30-day operative mortality in the early-surgery group was 5.8%, which led to a survival disadvantage for these patients early in the trial. Mortality did not differ significantly between groups at 2 years, 4 years, or 6 years. Age, sex, or initial aneurysm size did not modify the overall hazard ratio. INTERPRETATION: Ultrasonographic surveillance for small abdominal aortic aneurysms is safe, and early surgery does not provide a long-term survival advantage. Our results do not support a policy of open surgical repair for abdominal aortic aneurysms of 4.0-5.5 cm in diameter.

Voies d'abord - Approaches:

1. Fassiadis, N., M. Roidl, et al. (2005). "Randomized clinical trial of vertical or transverse laparotomy for abdominal aortic aneurysm repair." Br J Surg 92(10): 1208-11.
BACKGROUND: The objective of this randomized trial was to evaluate the incidence of incisional hernia after transverse or vertical incisions for open aortic aneurysm repair. METHODS: The study group comprised 69 patients who underwent elective aneurysm repair between November 1998 and November 2000 (60 men, nine women; mean age 72.8 (range 56-95) years). Patients were randomized to a transverse (n = 32) or vertical (n = 37) incision for the procedure. Of the 42 patients who were still alive in February 2004, 37 (15 transverse, 22 vertical incisions) attended for review. Laparotomy scars were assessed both clinically and ultrasonographically by the same examiner, to look for incisional hernia. RESULTS: Mean follow-up was 4.4 years. A multivariable logistic regression analysis revealed that the type of incision was the only parameter that significantly influenced the rate of incisional hernia: six of 15 patients with a transverse laparotomy versus 20 of 22 with a vertical laparotomy (P = 0.010). CONCLUSION: The incidence of incisional hernia was high after aortic aneurysm repair, but was lower in patients who had a transverse incision.

2. Weber, G., M. Istvan, et al. (1997). "A randomized comparison between minilaparotomy and conventional approach for aortoiliac reconstructive surgery." Acta Chir Hung 36(1-4): 391-2.
To decrease the surgical stress on patients undergoing aortic surgery the authors developed a less extensive procedure utilizing minilaparotomy and videoendoscopy. From June 1993 through July 1996, patients undergoing surgery for aortoiliac occlusive disease were randomized comparing the minilaparotomy (ML) with conventional approach (CA). Sixty-two patients participated in this trial, with 37 in the ML group and 25 in CA group. There were no significant differences between the groups in terms of age, sex or comorbid conditions. The incidence of intraoperative complications was similar for both groups. After surgery, nasogastric drainage was significantly (p = 0.01) shorter, bowel movement and initiation of alimentation began earlier in ML group. Both groups of patients showed a significant decrease in vital capacity and forced exspiration volume postoperatively, but this depression was significantly higher (p = 0.05) in CA group. The ML group also had significantly shorter stay in the intensive care unit (p = 0.001) and the mean duration of the postoperative hospital stay was also significantly less (p = 0.05). Generally, the patients operated by ML method during the postoperative recovery period required less analgesia, and expressed better "overall satisfaction". In long-term follow-up (mean 21 months), there was no significant difference in survival rates between two groups.

3. Sicard, G. A., J. M. Reilly, et al. (1995). "Transabdominal versus retroperitoneal incision for abdominal aortic surgery: report of a prospective randomized trial." J Vasc Surg 21(2): 174-81; discussion 181-3.
PURPOSE: The purpose of this study was to perform a randomized, prospective trial that compares the transabdominal with the retroperitoneal approach to the aorta for routine infrarenal aortic reconstruction. METHODS: From August 1990 through November 1993, patients undergoing surgery for abdominal aortic aneurysm (AAA) disease or aortoiliac occlusive disease (AIOD) were asked to participate in a randomized trial comparing the transabdominal incision (TAI) to the retroperitoneal incision (RPI) for aortic surgery. One hundred forty-five patients were randomized, with 75 (41 with AAA and 34 with AIOD) in the TAI group and 70 (40 with AAA and 30 with AIOD) in the RPI group. There were no significant differences between the groups in terms of age, sex, postoperative pain control (epidural vs patient-controlled analgesia), or comorbid conditions, except for a higher incidence of chronic obstructive pulmonary disease in the TAI group (21 vs 8 patients). RESULTS: The incidence of intraoperative complications was similar for both groups. After surgery, the incidence of prolonged ileus (p = 0.013) and small bowel obstruction (p = 0.05) was higher in the TAI group. Overall, the RPI group had significantly fewer complications (p < 0.0001). The overall postoperative mortality rate (two deaths) was 1.4%, with both occurring in the TAI group (p = 0.507). The RPI group also had significantly shorter stays in the intensive care unit (p = 0.006), a trend toward shorter hospitalization (p = 0.10), lower total hospital charges (p = 0.019), and lower total hospital costs (p = 0.017). There was no difference in pulmonary complications (p = 0.71). In long-term follow-up (mean 23 months), the RPI group reported more incisional pain (p = 0.056), but no difference was found in incisional hernias or bulges (p = 0.297). CONCLUSIONS: We conclude that the RPI approach for abdominal aortic surgery is associated with fewer postoperative complications, shorter stays in the hospital and intensive care unit, and lower cost. There is, however, an increase in long-term incisional pain. Current methods of postoperative pain control seem to decrease the incidence of pulmonary complications.

Prothèses - Grafts:

1. Prager, M. R., T. Hoblaj, et al. (2003). "Collagen- versus gelatine-coated Dacron versus stretch PTFE bifurcation grafts for aortoiliac occlusive disease: long-term results of a prospective, randomized multicenter trial." Surgery 134(1): 80-5.
BACKGROUND: In this prospective randomized multicenter trial, knitted gelatine-coated Dacron, knitted collagen-coated Dacron, and stretch polytetrafluoroethylene (PTFE) aortic bifurcation grafts were compared for their long-term results. METHODS: Between 1991 and 1998, 149 patients undergoing elective revascularization for aortoiliac occlusive disease were prospectively randomized at 3 tertiary referral centers of vascular surgery. The patients received either gelatine-coated Dacron (GEL-D) grafts (n = 52), collagen-coated Dacron (COL-D) grafts (n = 49), or stretch PTFE grafts (n = 48). RESULTS: No intraoperative deaths were recorded. The 30-day mortality was 4%. The mean follow-up time was 97 months. Primary patency rates were 77% for GEL-D, 78% for COL-D, and 79% for PTFE at 8 years. The differences were not different (P >.8). Secondary corrected 8-year patency rates were also not significantly different (P >.5): 91% for GEL-D, 96% for COL-Dm and 90% for PTFE. Five Dacron and 1 PTFE grafts were affected by infections. CONCLUSIONS: Bifurcation grafts for revascularization of aortoiliac occlusive disease using these 3 materials were comparable in terms of primary and secondary patency and long-term complication rates.

2. Prager, M., P. Polterauer, et al. (2001). "Collagen versus gelatin-coated Dacron versus stretch polytetrafluoroethylene in abdominal aortic bifurcation graft surgery: results of a seven-year prospective, randomized multicenter trial." Surgery 130(3): 408-14.
BACKGROUND: A prospective randomized multicenter trial was performed to compare knitted gelatin-coated Dacron bifurcation grafts, knitted collagen-coated Dacron grafts, and stretch polytetrafluoroethylene (PTFE) grafts. METHODS: Between 1991 and 1998, 315 elective patients were randomized by age, gender, diabetes, runoff, indication (aneurysm, aortoiliac occlusive disease), and nicotine consumption at 3 centers of vascular surgery in Austria. The patients received gelatin-coated Dacron (GEL-D) grafts (n = 109), collagen-coated Dacron (COL-D) grafts (n = 100), or stretch PTFE grafts (n = 106). RESULTS: No intraoperative deaths occurred. The 30-day mortality was 3%. No difference was found between the 3 graft materials in long-term patency. The primary 5-year patency rates were 92% for GEL-D, 89% for COL-D, and 91% for stretch PTFE (P =.6001). The secondary 5-year patency rates also differed: 97% for GEL-D, 100% for COL-D, and 97% for stretch PTFE (P =.2062). Early occlusions were observed overall in 3% and late occlusions in 5% of patients. When both Dacron grafts were compared collectively with stretch PTFE, a difference was found in infection rate: Dacron 3% (6/209) versus PTFE 0% (0/106); P <.03. CONCLUSIONS: The bifurcation grafts of all 3 materials were comparable in primary and secondary patency rates, incidence of false aneurysms, and rate of perioperative complications. Graft infections were confined to the 2 Dacron grafts and did not occur in stretch PTFE grafts.

3. Quarmby, J. W., K. G. Burnand, et al. (1998). "Prospective randomized trial of woven versus collagen-impregnated knitted prosthetic Dacron grafts in aortoiliac surgery." Br J Surg 85(6): 775-7.
BACKGROUND: Despite the theoretical advantages of coating knitted grafts with a material designed to reduce blood loss, their performance has not been directly compared with woven grafts in a prospective randomized trial. The aim of this study was to compare the graft handling qualities and operative blood loss of the two types of arterial prosthesis, as well as complication rate and patient survival at 1 year. METHODS: A total of 267 consecutive patients having surgery for occlusive or aneurysmal disease of the aortoiliac arteries were randomized to receive woven (141 patients) or knitted collagen-impregnated Dacron (126 patients) grafts. Graft patency was assessed on discharge and at 1 year by duplex imaging. RESULTS: Mean(s.d.) intraoperative blood loss was statistically greater with woven grafts (1690(1424) ml) compared with knitted (1363(1172) ml) (P = 0.049). An insignificant 1-year increase in mean(s.d.) graft diameter of 1.2(0.2) mm was found at the distal anastomosis in the knitted group. There was no difference in graft patency between the groups and only one graft became infected. CONCLUSION: This study suggests that knitted and woven grafts have similar clinical performance and therefore the less expensive material (woven) should usually be selected unless haemorrhagic complications are anticipated.