The Contemporary Impact of Body Mass Index on Open Aortic Aneurysm Repair

INTRODUCTION

The Centers for Disease Control and Prevention (CDC) has deemed obesity a national epidemic and contributor to other leading causes of death including heart disease, stroke, and diabetes. Accordingly, the role of body mass index (BMI) and its impact on surgical outcomes has been a focus of persistent investigation. The purpose of this study was to quantify the effect of BMI on open abdominal aortic aneurysm repair (oAAA) outcomes in contemporary practice.

METHODS

All elective oAAAs in the VQI (2010-2021) were identified. End-points included 30-day death, in-hospital complications and 1-year mortality. Patients were stratified into four BMI cohorts (BMI<18.5, 18.5≤BMI<25, 25≤BMI<30, BMI≥30). Spline interpolation was used to explore a potential non-linear association between BMI and perioperative mortality. Mixed-effects Cox regression was used to assess the association between BMI and 1-year survival.

RESULTS

9,479 patients underwent oAAA over the study interval (median age-70, 74%-male, BMI 27±6). Lower BMI patients(<18.5) compared to higher BMI(>30) patients were more likely to be women (53% vs. 32%;p<.0001), current smokers(65% vs. 50%;p<.0001), and have COPD(58% vs. 37%;p<.0001). In contrast, an increased BMI was associated with a greater prevalence of diabetes and CAD (DM-26% vs. 6%;p<.0001; CAD-27% vs. 20%;p=.01). There was no difference in cross-clamp position or visceral/renal bypass between groups, though low BMI patients necessitated more frequent infrainguinal bypass(5% vs. 2%;p=.0002). 30-day mortality and in-hospital complications were greater among low BMI patients(30-day mortality:12% vs. 4%;p<.0001;complications-47% vs. 37%;p<.0001). Interestingly, low BMI conferred a nearly 2-fold increase in observed pulmonary complications(18% vs. 11%;p<.0001). Surgical site infections were twice as common among the lowest and highest BMI groups(4% vs. 2%;p<.0001). 1-year mortality was greatest among low BMI patients(23% vs. 9%;p<.0001). Adjusted spline-fit analysis demonstrated increased mortality among patients with BMI<21 or >34(BMI<18.5-HR 2.1, 95%CI 1.6-2.8;p<.0001; BMI>34-HR 1.3, 95%CI 1.1-1.6;p=.009).

CONCLUSION

Both low (<18.5) and high (>34) BMI were associated with increased oAAA mortality in current practice. Despite the perception that obesity confers substantial surgical risk during oAAA, diminished BMI was associated with a 3-fold increase in 30-day and 1-year mortality. It appears that BMI extremes are distinct proxies for differential clinical phenotypes and should inform risk stratification for oAAA repair.

Impact of an emergency endovascular aneurysm repair protocol on 30-day ruptured abdominal aortic aneurysm mortality

OBJECTIVE

To characterize the longstanding impact of an emergency endovascular aneurysm repair (EVAR) protocol for ruptured abdominal aortic aneurysm (rAAA) on 30-day mortality.

METHODS

All adult patients with an rAAA who underwent a surgical or endovascular intervention at a tertiary care center between March 2001 and December 2018 were evaluated. An emergency EVAR protocol was introduced in January 2004. The primary outcome was 30-day mortality, which was calculated using risk-adjusted logistic regression for the preprotocol and postprotocol periods. A risk-adjusted cumulative sum analysis examined changes in 30-day mortality after protocol implementation.

RESULTS

We identified 376 patients with rAAA between 2001 and 2018 (75 preprotocol and 301 postprotocol), with a decreasing incidence of rAAA during the study period. The introduction of the protocol in 2004 was associated with increased EVAR use (63.6% vs 6.7%; P < .001). Patients managed according to the protocol were more frequently unstable (systolic blood pressure [SBP] of ≤80 mm Hg, 46.5% postprotocol vs 22.7% preprotocol; P < 0.001), with a lower average SBP (87.4 mm Hg postprotocol vs 106 mm Hg preprotocol; P < .001) and worse renal function (estimated glomerular filtration rate 61.5 mL/min postprotocol vs 83.2 mL/min preprotocol; P < .001). The risk-adjusted 30-day mortality was 23.2% with the emergency EVAR protocol, versus 35.8% preprotocol (P = .0727). A subgroup analysis demonstrated improved the 30-day mortality for unstable patients (SBP of ≤80 mm Hg) at 38.0% (vs 62.4% preprotocol introduction; P = .0190). A cumulative sum analysis demonstrated worse than expected mortality outcomes in the preprotocol period, and stability of surgical performance over 15 years after protocol introduction.

CONCLUSIONS

On reflection of a 17-year experience with EVAR for rAAA, the implementation of an emergency EVAR protocol demonstrated stable surgical performance for all patients with an rAAA and evidence of improved 30-day mortality for unstable patients with an rAAA. Since the protocol introduction, EVAR has become a mainstay intervention and, despite an increase in comorbid patients, the overall incidence of rAAA is declining. EVAR should be considered the first-line intervention for the appropriate patient unstable with an rAAA.

High-performance detection of an abdominal aortic aneurysm biomarker by immunosensing

Abdominal aortic aneurysm (AAA) is a serious, life-threatening vascular disease that presents as an enlarged area of the aorta, which is the main artery that carries blood away from the heart. AAA may occur at any location in the aorta, but it is mainly found in the abdominal region. A ruptured AAA causes serious health issues, including death. Traditional imaging techniques, such as computed tomography angiogram, magnetic resonance imaging, and ultrasound sonography, have been used to identify AAAs. Circulating biomarkers have recently become attractive for diagnosing AAAs due to their cost-effectiveness compared to imaging. Insulin-like growth factor 1 (IGF-1), a secreted hormone vital for human atherosclerotic plaque stability, has been found to be an efficient biomarker for AAA identification. In this report, immunosensing was performed by using an InterDigitated electrode (IDE) sensor to detect circulating levels of IGF-1. The detection limit of IGF-1 was found to be 100 fM with this sensor. Moreover, related protein controls (IGF-2 and IGFBP3) were not detected with the same antibody, indicating selective IGF-1 detection. Thus, immunosensing by using an IDE sensor may help to effectively diagnose AAAs and represents a basic platform for further development.

Comparative effectiveness of open surgery versus endovascular repair for hemodynamically stable and unstable ruptured abdominal aortic aneurysm

Several observational studies and randomized trials have compared open surgery (OS) and endovascular aortic repair (EVAR) for ruptured abdominal aortic aneurysm (rAAA). However, none of these studies addressed optimal management of hemodynamically (hd) unstable patients. Our objective was to compare perioperative outcomes in patients undergoing OS vs EVAR for hd-stable and hd-unstable rAAAs.This retrospective study was conducted in West China Hospital from January 2005 to December 2015. Unstable patients were defined as those who have at least 1 of the following: preoperative shock, preoperative transfusion >4 units, preoperative intubation, cardiac arrest, or unconsciousness. Univariable and multivariable logistic regression analyses were performed.Of the 102 patients, 70.6% underwent OS and 29.4% EVAR. About 46.1% were unstable, and for these patients, OS was performed in 70.2% and EVAR in 29.8%. The 30-day mortality was 23.6% (OS, 25.6%; EVAR, 18.8%; P = .585) for hd-stable patients and was 42.6% (OS, 45.5%; EVAR, 35.7%; P = .537) for hd-unstable patients. Patients with OS had longer operative time and more transfusion. Amongst hd-stable patients, OS subgroup had a higher rate of pneumonia (33.3% vs 6.3%, P = .045), longer intensive care unit (ICU) stay (43.2 vs 15.2 hours, P = .02), and length of stay (11.6 vs 8.6 days, P = .041). Among hd-unstable patients, OS subgroup had a longer ICU stay (134.3 vs 63.8 hours, P = .047). Hospitalization costs of OS group were significantly lower than those of EVAR group, regardless of hemodynamic stability.Approximately one-third of patients with rAAA were treated by EVAR at our institution. EVAR may be the preferred approach for anatomically suitable rAAAs. However, patients treated by EVAR had a similar mortality compared with those treated by OS. In addition, OS is not an independent factor for a higher 30-day mortality, and the costs of OS were much cheaper than those of EVAR. Therefore, OS is difficult to replace, especially in developing countries.

Endovascular repair versus open repair in the treatment of ruptured aortic aneurysms: a systematic review

INTRODUCTION

Rupture of abdominal aortic aneurysm remains a fatal event in up to 65% of cases and emergency open surgery (ruptured open aneurysm repair or rOAR) has a great intraoperative mortality of about 30-50%. The introduction of endovascular repair of abdominal aortic aneurysm (ruptured endovascular aneurysm repair or rEVAR) has rapidly challenged the conventional approach to this catastrophic event. The purpose of this systematic review is to compare the outcomes of open surgical repair and endovascular interventions.

EVIDENCE ACQUISITION

A literature search was performed using Medline, Scopus, and Science Direct from August 2010 to March 2017 using keywords identified and agreed by the authors. Randomized trials, cohort studies, and case-report series were contemplated to give a breadth of clinical data.

EVIDENCE SYNTHESIS

Ninety-three studies were included in the final analysis. Thirty-five (50.7%) of the listed studies evaluating the within 30 days mortality rates deposed in favor of rEVAR, while the others (comprising all four included RCTs) failed detecting any difference. Late mortality rates were found to be lower in rEVAR group in seven on twenty-seven studies (25.9%), while one (3.7%) reported higher mortality rates following rEVAR performed before 2005, one found lower incidence of mortality at 6 months in the endovascular group but higher rates in the same population at 8 years of follow-up, and the remaining (66.7%) (including all three RCTs) failed finding any benefit of rEVAR on rOAR. A lower incidence of complications was reported by thirteen groups (46.4%), while other thirteen studies did not find any difference between rEVAR and rOAR. Each of these two conclusions was corroborated by one RCTs. Other two studies (7.2%) found higher rates of tracheostomies, myocardial infarction, and acute tubular necrosis or respiratory, urinary complications, and acute renal failure respectively in rOAR group. The majority of studies (59.0%, 72.7%, and 89.3%, respectively) and all RCTs found significantly lower rates of length of hospitalization, intensive care unit transfer, and blood loss with or without transfusion need in rEVAR group. The large majority of the studies did not specified neither the type nor the brands of employed stent grafts.

CONCLUSIONS

The bulk of evidence regarding the comparison between endovascular and open surgery approach to RAAA points to: 1) non-inferiority of rEVAR in terms of early (within 30 days) and late mortality as well as rate of complications and length of hospitalization, with trends of better outcomes associated to the endovascular approach; 2) significantly better outcomes in terms of intensive care unit transfer and blood loss with or without transfusion need in the rEVAR group. These conclusions reflect the results of the available RCTs included in the present review. Thus rEVAR can be considered a safe method in treating RAAA and we suggest that it should be preferred when technically feasible. However, more RCTs are needed in order to give strength of these evidences, bring to definite clinical recommendations regarding this subject, and assess the superiority (if present) of one or more brands of stent grafts over the others.

Ruptured abdominal aortic aneurysm: Is endovascular aneurysm repair the answer for everybody?

Treatment paradigms for elective repair of asymptomatic abdominal aortic aneurysms (AAA) have evolved during the past 2 decades, with endovascular aneurysm repair as the preferred treatment modality. The patient care strategy for emergent treatment for ruptured AAA is not as straightforward, due in part to surgeon expertise and stent-graft availability at the institution. Although most reports have extrapolated elective endovascular aneurysm repair feasibility data to the ruptured AAA patient and the aneurysm anatomy, these expectations should be interpreted with caution. In the absence of level I evidence, and lack of adequate local hospital resources, endovascular aneurysm repair-first policy might not be feasible for all the patients who present with ruptured AAA.

Endovascular repair versus open surgery in patients in the treatment of the ruptured of aneurysms abdominal

INTRODUCTION

Rupture of abdominal aortic aneurysm is still a difficult challenge for the vascular surgeon due to the high perioperative mortality. The aim of our study is to describe the characteristics of the population as well as to compare morbidity and mortality in patients undergoing open surgery or endovascular repair in our center.

METHODS

Database with 82 rAAA between January 2002-December 2014, studying two cohorts, open surgery and endovascular repair. Epidemiologic, clinical, surgical techniques, perioperative mortality and complications are analyzed.

RESULTS

82 rAAA cases were operated (men: 80, women: 2). Mean age 72±9.6 years. 76.8% (63 cases) was performed by open surgery.

BACKGROUND

smokers 59, 7%, alcoholism 19.5%, DM 10.9%, AHT: 53.6%, dyslipidemia 30.5%. The most frequent clinical presentation was abdominal pain with lumbar irradiation: 50 cases (20.7% associating syncope). Overall hospital mortality was 58.5%. Hemodynamic shock prior to intervention was associated with increased mortality (p <.001). Anemia, leukocytosis, aneurysm size, sex and age did not show a statistically significant difference with respect to mortality (p>.05). The presence of iliac aneurysms was associated with increased mortality (p <.0045). Perioperative mortality in endovascular repair was 42%, and in open surgery was 63.5% (p>.05). Hospital stay was lower in the endovascular group (p=.3859).

CONCLUSIONS

Hemodynamic shock and the presence of concomitant iliac aneurysms have a statistically significant association with perioperative mortality in both groups. We found clinically significant differences in mortality, complications and hospital stay when comparing both groups with better results for EVAR, without statistically significant differences.

Endovascular vs. Open Repair for Ruptured Abdominal Aortic Aneurysm

Background

Patients presenting with ruptured abdominal aortic aneurysms are most often treated with open repair despite the fact that endovascular aneurysm repair is a less invasive and widely accepted method with clear benefits for elective aortic aneurysm patients. A debate exists regarding the definitive benefit in endovascular repair for patients with a ruptured abdominal aortic aneurysm. The aim of this literature review was to determine if any trends exist in favor of either open or endovascular repair.

Material/Methods

A literature search was performed using PUBMED, OVID, and Google Scholar databases. The search yielded 64 publications.

Results

Out of 64 publications, 25 were retrospective studies, 12 were population-based, 21 were prospective, 5 were the results of RCTs, and 1 was a case-series. Sixty-one studies reported on early mortality and provided data comparing endovascular repair (rEVAR) and open repair (rOR) for ruptured abdominal aneurysm groups. Twenty-nine of these studies reported that rEVAR has a lower early mortality rate. Late mortality after rEVAR compared to that of rOR was reported in 21 studies for a period of 3 to 60 months. Results of 61.9% of the studies found no difference in late mortality rates between these 2 groups. Thirty-nine publications reported on the incidence of complications. Approximately half of these publications support that the rEVAR group has a lower complication rate and the other half found no difference between the groups. Length of hospital stay has been reported to be shorter for rEVAR in most studies. Blood loss and need for transfusion of either red cells or fresh frozen plasma was consistently lower in the rEVAR group.

Conclusions

Differences between the included publications affect the outcomes. Randomized control trials have not been able to provide clear conclusions. rEVAR can now be considered a safe method of treating rAAA, and is at least equal to the well-established rOR method.

Comparison of Efficacy of Endovascular Aneurysm Repair Versus Open Surgical Repair in Middle/High-Risk Patients With Abdominal Aortic Aneurysm

To explore the efficacy of endovascular aneurysm repair (EVAR) compared with traditional open surgical repair (OSR) in the treatment of middle/high-risk patients with abdominal aortic aneurysm (AAA). With a retrospective method, we analyzed the clinical data of 57 patients with middle/high-risk AAA admitted to Linyi People's Hospital Affiliated to Shandong University from January 2010 to January 2014. Twenty-eight of the 57 patients received EVAR and 29 others received OSR. Statistical analysis was conducted by the design of spreadsheet according to preoperative, intraoperative, perioperative, and postoperative follow-up relevant information. Our study showed that the difference in baseline characteristics of different therapies in middle/high-risk AAA patients was not statistically significant in preoperative period (P > 0.05). In intraoperative period, the efficacy of middle/high-risk AAA patients in EVAR group was significantly superior to OSR group in terms of blood loss, blood transfusion, and general anesthesia rate (all P < 0.01). In perioperative period, the ICU observation time and the average fasting time of middle/high-risk AAA patients in EVAR group were remarkably lower than OSR group (all P < 0.01), but the average hospital stay and the operation cost of middle/high-risk AAA patients in EVAR group were notably higher than OSR group. In postoperative follow-up period, OSR group was identified with a lower incidence of surgery-related complications than EVAR group (P < 0.05), but EVAR group was demonstrated with a higher survival rate than OSR group (P < 0.05); after 12 months of follow-up, SF-36 scale scores in OSR group were higher than EVAR group (P < 0.05). In conclusion, EVAR may have a better short-term effect, whereas OSR may have a better long-term effect in the treatment of middle/high-risk AAA patients.