Randomized clinical trial of remote ischaemic preconditioning versus no preconditioning in the prevention of perioperative myocardial infarction during open surgery for ruptured abdominal aortic aneurysm.

BACKGROUND: Remote ischaemic preconditioning (RIPC) has been suggested as a means of protecting vital organs from reperfusion injury during major vascular surgery. This study was designed to determine whether RIPC could reduce the incidence of perioperative myocardial infarction (MI) during open surgery for ruptured abdominal aortic aneurysm (AAA). Secondary aims were to see if RIPC could reduce 30-day mortality, multiple organ failure, acute intestinal ischaemia, acute kidney injury and ischaemic stroke. METHODS: This randomized, non-blinded clinical trial was undertaken at three vascular surgery centres in Denmark. Patients who had open surgery for ruptured AAA were randomized to intervention with RIPC or control in a 1 : 1 ratio. Postoperative complications and deaths were registered, and ECG and blood samples were obtained daily during the hospital stay. RESULTS: Of 200 patients randomized, 142 (72 RIPC, 70 controls) were included. There was no difference in rates of perioperative MI between the RIPC and control groups (36 versus 43 per cent respectively), or in rates of organ failure. However, in the per-protocol analysis 30-day mortality was significantly reduced in the RIPC group (odds ratio 0·46, 95 per cent c.i. 0·22 to 0·99; P = 0·048). CONCLUSION: RIPC did not reduce the incidence of perioperative MI in patients undergoing open surgery for ruptured AAA. Registration number: NCT00883363 ( http://www.clinicaltrials.gov).

Body Mass Index and Operating Times in Vascular Procedures.

INTRODUCTION: The influence of body mass index (BMI) on operating times in central and peripheral vascular surgical procedures was investigated. REPORT: A national cohort of Danish patients who underwent a vascular procedure between 1983 and 2012 was used for analysis. Data were analysed with pairwise comparisons of BMI groups for operating times using the independent samples Kruskall-Wallis test. DISCUSSION: A total of 3,255 carotid endarterectomies; 6,885 central vascular procedures; and 4,488 peripheral bypasses were included for the analysis. Median operating times for carotid endarterectomy and central vascular procedures were, respectively, 5 and 15 minutes longer in obese patients than in normal weight patients. This represents a 7% and 10% increase in median operating times, respectively. Linear and multi-adjusted linear regressions were conducted adjusting for confounders, showing a significant correlation between BMI and operating time. Obesity significantly increased the operating times in carotid endarterectomy and central vascular procedures. These may have ramifications for the individual operative stress but not necessarily on logistical operation planning.

Editor's Choice - Assessment of International Outcomes of Intact Abdominal Aortic Aneurysm Repair over 9 Years.

BACKGROUND: Case mix and outcomes of complex surgical procedures vary over time and between regions. This study analyses peri-operative mortality after intact abdominal aortic aneurysm (AAA) repair in 11 countries over 9 years. METHODS: Data on primary AAA repair from vascular surgery registries in 11 countries for the years 2005-2009 and 2010-2013 were analysed. Multivariate adjusted logistic regression analyses were carried out to adjust for variations in case mix. RESULTS: A total of 83,253 patients were included. Over the two periods, the proportion of patients ≥80 years old increased (18.5% vs. 23.1%; p < .0001) as did the proportion of endovascular repair (EVAR) (44.3% vs. 60.6; p < .0001). In the latter period, 25.8% of AAAs were less than 5.5 cm. The mean annual volume of open repairs per centre decreased from 12.9 to 10.6 between the two periods (p < .0001), and it increased for EVAR from 10.0 to 17.1 (p < .0001). Overall, peri-operative mortality fell from 3.0% to 2.4% (p < .0001). Mortality for EVAR decreased from 1.5% to 1.1% (p < .0001), but the outcome worsened for open repair from 3.9% to 4.4% (p = .008). The peri-operative risk was greater for octogenarians (overall, 3.6% vs. 2.1%, p < .0001; open, 9.5% vs. 3.6%, p < .0001; EVAR, 1.8% vs. 0.7%, p < .0001), and women (overall, 3.8% vs. 2.2%, p < .0001; open, 6.0% vs. 4.0%, p < .0001; EVAR, 1.9% vs. 0.9%, p < .0001). Peri-operative mortality after repair of AAAs <5.5 cm was 4.4% with open repair and 1.0% with EVAR, p < .0001. CONCLUSIONS: In this large international cohort, total peri-operative mortality continues to fall for the treatment of intact AAAs. The number of EVAR procedures now exceeds open procedures. Mortality after EVAR has decreased, but mortality for open operations has increased. The peri-operative mortality for small AAA treatment, particularly open surgical repair, is still considerable and should be weighed against the risk of rupture.

Male Sex Associated with Increased Long-term Cardiovascular Mortality after Peripheral Vascular Surgery for Atherosclerosis Despite Optimal Medical Treatment.

BACKGROUND: The cardiovascular burden and consequences of peripheral atherosclerosis appear to differ between men and women. Data regarding long-term outcomes, including the impact of medical prophylactic treatment, are insufficient. This study examined long-term outcomes according to sex following primary vascular surgery, adjusted for multiple variables as well as recommended medical prophylaxis. METHODS: All Danish patients who underwent peripheral vascular surgery from January 2000 to December 2007 were stratified into five procedural groups: (a) aorto-iliac bypass or thromboendarterectomy, (b) femoro-femoral crossover, (c) thromboendarterectomy of the femoral arteries, (d) infrainguinal bypass, or (e) axillo- uni-, and bifemoral bypass. Data were analyzed according to sex for differences in myocardial infarction, stroke, and death, individually and combined, after surgery. RESULTS: A total of 11,234 patients were included: 6,289 males and 4,945 females. The overall adjusted hazard ratio for male patients compared with female patients for death was 1.11 (95% CI 1.06-1.17), for MI was 1.16 (95% CI 1.04-1.29), for stroke was 0.99 (95% CI 0.89-1.11), and for any major adverse cardiovascular event was 1.10 (95% CI 1.05-1.16). CONCLUSIONS: These findings show that, despite indication, severity, and concomitant medical treatment of peripheral artery disease, men have a higher risk of mortality and adverse cardiovascular events following surgery for peripheral arterial disease.