The long-term outcomes of open and endovascular repair for abdominal aortic aneurysm: A meta-analysis

Outcomes of Endovascular Aneurysm Repair (EVAR) Compared to Open Repair in Abdominal Aortic Aneurysm: An Umbrella Meta-Analysis

This umbrella meta-analysis aims to investigate two surgical treatments for abdominal aortic aneurysm (AAA): endovascular aneurysm repair (EVAR) and open surgery repair (OSR). Our study aims to elucidate the 30-day mortality rate, reintervention rates, and aneurysm-related mortality in EVAR versus OSR for AAA.  We conducted a comprehensive assessment of meta-analyses (n = 34 articles) comparing EVAR and OSR for AAA. We adhered to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) protocol and considered statistical significance at P ≤ 0.05. For the 30-day mortality rate, a pooled odds ratio (pOR) of 0.59 (95% confidence interval [CI] 0.45-0.77, P = 0.0001, and I2 = 98%) indicates that EVAR was associated with a lower risk of mortality compared to OSR. For reintervention rates, a pOR of 1.33 (95% CI = 0.98-1.82, P = 0.11, and I2 = 90%). In aneurysm-related mortality, a pOR of 0.78 (95% CI = 0.63-0.97, P = 0.03, and I2 = 43%). In postoperative rupture of aneurysm, a pOR of 3.28 (95% CI = 2.16-4.98, P < 0.00001, and I2 = 50%). Furthermore, when analyzing systemic complications, only for visceral ischemia, significant results showed lower odds for EVAR, with a pOR of 0.57 (95% CI = 0.40-0.80, P = 0.001, and I2 = 0%) was found.  EVAR is better in terms of short-term mortality rate and aneurysm-related mortality. Furthermore, EVAR is still a safer procedure in elective settings, as the studies we included recruited patients for this setting. However, given the high reintervention rates and recent developments in surgical techniques and materials, more recent data and extensive research are needed.

Umbrella review and meta-analysis of reconstructed individual patient data of mortality following conventional endovascular and open surgical repair of infrarenal abdominal aortic aneurysm

OBJECTIVES

This umbrella review aims to quality assess published meta-analyses, conduct a de-novo meta-analysis of the available randomized control trials (RCTs), and test the hypothesis that there is a long-term difference in mortality between OSR and EVAR.

METHODS

A systematic search was conducted in MEDLINE and EMBASE's bibliographic databases (June 2022). Data were extracted using standardized extraction forms. The methodological quality of publications was assessed using the ROBIS tool. Data were analyzed with 'one-stage' and 'two-stage' approaches.

RESULTS

According to two-stage analysis, EVAR has significantly favorable mortality for up to four years (increasing evidence). Subsequently, until the longest available time period, there is no difference between EVAR and OSR; all the results are statistically non-significant.In one stage analysis, the Cox model demonstrated a non-significant (weak evidence) hazard ratio of 1.03 (95% confidence interval [CI]: 0.94-1.12) in favor of OSR. The best-fitting parametric model (generalized gamma), leads to an hazard ratio of 0.97 (95% CI: 0.93-1.01) in favor of EVAR, with the results approaching significance (weak evidence).

CONCLUSION

The results of this umbrella systematic review and meta-analysis failed to demonstrate any difference in long-term mortality following planned EVAR, compared with OSR of infrarenal AAA.

Cost-effectiveness of a population-based AAA screening program for men over 65 years old in Iran

BACKGROUND

Screening program tend to recognized patients in their early stage and consequently improve health outcomes. Cost-effectiveness of the abdominal aortic aneurysm (AAA) screening program has been scarcely studied in developing countries. We sought to evaluate the cost-effectiveness of a screening program for the abdominal aortic aneurysm (AAA) in men aged over 65 years in Iran.

METHODS

A Markov cohort model with 11 mutually exclusive health statuses was used to evaluate the cost-effectiveness of a population-based AAA screening program compared with a no-screening strategy. Transitions between the health statuses were simulated by using 3-month cycles. Data for disease transition probabilities and quality of life outcomes were obtained from published literature, and costs were calculated based on the price of medical services in Iran and the examination of the patients' medical records. The outcomes were life-years gained, the quality-adjusted life-year (QALY), costs, and the incremental cost-effectiveness ratio (ICER). The analysis was conducted for a lifetime horizon from the payer's perspective. Costs and effects were discounted at an annual rate of 3%. Uncertainty surrounding the model inputs was tested with deterministic and probabilistic sensitivity analyses.

RESULTS

The mean incremental cost of the AAA screening strategy compared with the no-screening strategy was $140 and the mean incremental QALY gain was 0.025 QALY, resulting in an ICER of $5566 ($14,656 PPP) per QALY gained. At a willingness-to-pay of 1 gross domestic product (GDP) per capita ($5628) per QALY gained, the probability of the cost-effectiveness of AAA screening was about 50%. However, at a willingness-to-pay of twice the GDP per capita per QALY gained, there was about a 95% probability for the AAA screening program to be cost-effective in Iran.

CONCLUSIONS

The results of this study showed that at a willingness-to-pay of 1 GDP per capita per QALY gained, a 1-time AAA screening program for men aged over 65 years could not be cost-effective. Nevertheless, at a willingness-to-pay of twice the GDP per capita per QALY gained, the AAA screening program could be cost-effective in Iran. Further, AAA screening in high-risk groups could be cost-effective at a willingness-to-pay of 1 GDP per capita per QALY gained.

Management of abdominal aortic aneurysm in nonagenarians: A single-centre experience

OBJECTIVE

In the last decades, life expectancy has increased worldwide considerably. Traditionally, very elderly patients have been considered too frail to undergo major vascular interventions. Considering that abdominal aortic aneurysm is an age-related disease, there is an increasing need of a correct management of the disease even in nonagenarians, but data are still scarce. The purpose of this single-centre study is to report early and mid-term outcomes of all-comer abdominal aortic aneurysm patients in their 10th decades of age.

METHODS

A retrospective review of our prospectively maintained database identified a total of 33 patients aged ≥ 90 presenting with abdominal aortic aneurysm between 2014 and 2019. Elective and emergency repairs were both considered. Early technical success and mortality rate at 30 days were considered as primary outcomes. Mid-term clinical success was reported, and overall survival, freedom from aneurysm-related death, re-interventions and endoleaks were estimated with the Kaplan-Meier method, stratified for elective of emergency repair and type of treatment.

RESULTS

The mean age was 91.7 (range 90-96), and 63.6% were male. Mean abdominal aortic aneurysm diameter was 67.4 ± 16.8 mm. Sixteen patients were admitted for rupture abdominal aortic aneurysm: three untreated, five underwent open and seven underwent endovascular aneurysm repair (EVAR), with an early mortality rate of 100, 100 and 42.8%, respectively. Eighteen (60%) patients were asymptomatic, and all underwent elective EVAR, with an early mortality rate of 0%. At one-month follow-up, clinical success was 84% in EVAR group. At a median follow-up of 22.4 ± 14.5 months, no abdominal aortic aneurysm-related death was registered. Freedom from all cause of mortality was 77.3, 59.4 and 40.7% at one, two and three years. Freedom from endoleaks was 95.4% at one month and 61.7% at one and three years. Freedom from reintervention was 85.8% at three years.

CONCLUSION

Elective EVAR in nonagenarians is associated with acceptable early and mid-term outcomes. Age by itself should not be considered an exclusion criterion for treatment.

Meta-analysis of phase-specific survival after elective endovascular versus surgical repair of abdominal aortic aneurysm from randomized controlled trials and propensity score-matched studies

OBJECTIVE

Although endovascular aneurysm repair (EVAR) for abdominal aortic aneurysm (AAA) significantly decreases perioperative mortality compared with open surgical repair (OSR), we have not concluded superiority between EVAR and OSR beyond the perioperative period. The aim of this study was to compare phase-specific survival after EVAR vs OSR.

METHODS

The review was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guideline. Embase and MEDLINE were searched up to November 2019 to identify randomized controlled trials and propensity score-matched studies that investigated ≥2-year all-cause mortality (primary outcome) after EVAR vs OSR for intact infrarenal AAA. For each study, the hazard ratio (HR) with 95% confidence interval (CI) of mortality for EVAR vs OSR was calculated using survival curves for the following specific phases: early term (0-2 years after repair), midterm (2-6 years after repair), long term (6-10 years after repair), and very long term (≥10 years after repair). The risk ratio (RR) in the perioperative (in-hospital or 30-day) period was also extracted. Phase-specific HRs or RRs were separately pooled using the random effects model. Sensitivity analyses were performed by removing one study at a time to confirm that our findings were not derived from any single study. Funnel plot asymmetry was also examined using the linear regression test.

RESULTS

Our search identified four randomized controlled trials and seven propensity score-matched studies enrolling a total of 106,243 AAA patients assigned to EVAR (n = 53,123) or OSR (n = 53,120). The mortality after EVAR compared with OSR was significantly lower in the perioperative period (RR, 0.39; 95% CI, 0.29-0.51; P < .00001) and similar in the early-term period (HR, 0.93; 95% CI, 0.84-1.03; P = .16). Notably, significantly higher mortality was observed in the EVAR group compared with the OSR group in the midterm period (HR, 1.15; 95% CI, 1.03-1.29; P = .01). However, similar mortality was observed between the EVAR group and the OSR group in the long-term (HR, 1.06; 95% CI, 0.96-1.17; P = .27) and very-long-term (HR, 1.17; 95% CI, 0.93-1.47; P = .19) periods. In sensitivity analyses, the significant benefit of EVAR in the perioperative period and that of OSR in the midterm period were not changed. No funnel plot asymmetry was identified in all analyses.

CONCLUSIONS

Compared with OSR, EVAR was associated with lower perioperative mortality and higher mortality in the midterm period for intact infrarenal AAA. The superiority of EVAR was absent in the early-term period, and the inferiority of EVAR in the midterm period disappeared in the long-term and very-long-term periods.

Long-Term Outcomes of Endovascular vs Open Surgical Repair for Abdominal Aortic Aneurysms: A Meta-Analysis of Randomized Trials

OBJECTIVE

The aim of this meta-analysis was to investigate whether Endovascular abdominal aortic aneurysm repair (EVAR) is inferior to open surgical repair in terms of adverse events during late follow up, defined as >8 years after the procedure.

BACKGROUND

EVAR is associated with reduced morbidity and mortality compared to open surgery in the early perioperative period. However, it is unknown whether this pattern remains during long-term follow up >8 years.

METHODS

A meta-analysis was conducted with the use of random effects modeling. Hazard ratios were calculated for mortality at different time intervals, and risk ratios were calculated in cases where the total number of events was available.

RESULTS

There was no difference in all-cause mortality during follow up of each study (HR: 1.04; 95%CI: 0.93-1.17; I² = 16.0%). Subgroup analyses for all-cause mortality at 4 to 8 years of follow up (HR: 1.13; 95%CI: 0.94-1.35; I² = 0.0%) and all-cause mortality at follow up >8 years (HR: 1.07; 95%CI: 0.89-0.28; I² = 36.6%) also did not show any significant difference between the two approaches. The risks of aneurysm-related mortality and aneurysm rupture were similar during follow-up. However, the cumulative risk for reintervention during follow up was greater in the EVAR group (RR: 2.18; 95%CI: 1.50-3.17; I² = 76.1%) and occurred in 29% vs 15% of patients in the EVAR vs surgery groups respectively.

CONCLUSIONS

EVAR and open surgical repair of AAA are equally safe and have no difference in all-cause mortality. However, endovascular repair is associated with an increased need for re-intervention. Emerging technology in endovascular devices will likely further improve the outcomes of EVAR. Subject codes: Meta-analysis; aneurysm; atherosclerosis; complications.

Editor's Choice - Endovascular vs. Open Repair for Abdominal Aortic Aneurysm: Systematic Review and Meta-analysis of Updated Peri-operative and Long Term Data of Randomised Controlled Trials

OBJECTIVE

The objective was to investigate whether endovascular aneurysm repair (EVAR) has better peri-operative and late clinical outcomes than open repair for non-ruptured abdominal aortic aneurysm.

METHODS

Electronic bibliographic sources (MEDLINE, EMBASE, and CENTRAL) were searched up to July 2019 using a combination of thesaurus and free text terms to identify randomised controlled trials (RCTs) comparing the outcomes of EVAR and open repair. The systematic review was conducted according to the Preferred Reporting Items for Systematic reviews and Meta-Analyses guidelines. Pooled estimates of dichotomous outcomes were calculated using odds ratio (OR) or risk difference (RD) and 95% confidence interval (CI). A time to event data meta-analysis was performed using the inverse variance method and the results were reported as summary hazard ratio (HR) and 95% CI.

RESULTS

Seven RCTs reporting a total of 2 983 patients were included in quantitative synthesis. Three of the trials reported long term follow up that extended to 15.8 years, 14.2 years, and 12.5 years. Meta-analysis found significantly lower odds of 30 day (OR, 0.36; 95% CI 0.20-0.66) and in hospital mortality with EVAR (RD -0.03; 95% CI -0.04 to -0.02). Meta-analysis of the three trials reporting long term follow up found no significant difference in all cause mortality at any time between EVAR and open repair (HR 1.02; 95% CI 0.93-1.13; p = .62). The hazard of all cause (HR 0.62; 95% CI 0.42-0.91) and aneurysm related death within six months (HR 0.42; 95% CI 0.24-0.75) was significantly lower in patients who underwent EVAR, but with further follow up, the pooled hazard estimate moved in favour of open surgery; in the long term (>8 years) the hazard of aneurysm related mortality was significantly higher after EVAR (HR 5.12; 95% CI 1.59-16.44). The risk of secondary intervention (HR 2.13; 95% CI 1.69-2.68), aneurysm rupture (OR, 5.08; 95% CI 1.11-23.31), and death due to rupture (OR, 3.57; 95% CI 1.87-6.80) was significantly higher after EVAR, but the risk of death due to cancer was not significantly different between EVAR and open repair (OR, 1.03; 95% CI 0.84-1.25).

CONCLUSION

Compared with open surgery, EVAR results in a better outcome during the first six months but carries an increased risk of aneurysm related mortality after eight years.

Long noncoding RNAs in key cellular processes involved in aortic aneurysms

Aortic aneurysm (AA) is a complex and dangerous vascular disease, featuring progressive and irreversible vessel dilatation. AA is typically detected either by screening, or identified incidentally through imaging studies. To date, no effective pharmacological therapies have been identified for clinical AA management, and either endovascular repair or open surgery remains the only option capable of preventing aneurysm rupture. In recent years, multiple research groups have endeavored to both identify noncoding RNAs and to clarify their function in vascular diseases, including aneurysmal pathologies. Notably, the molecular roles of noncoding RNAs in AA development appear to vary significantly between thoracic aortic aneurysms (TAAs) and abdominal aortic aneurysms (AAAs). Some microRNAs (miRNA - a non-coding RNA subspecies) appear to contribute to AA pathophysiology, with some showing major potential for use as biomarkers or as therapeutic targets. Studies of long noncoding RNAs (lncRNAs) are more limited, and their specific contributions to disease development and progression largely remain unexplored. This review aims to summarize and discuss the most current data on lncRNAs and their mediation of AA pathophysiology.

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This current review covers studies that have identified long non-coding RNAs in aortic aneurysm development and progression.

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We separately discuss transcripts and mechanisms of importance to thoracic as well as abdominal aortic aneurysms.

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Functional data on lncRNAs being identified are highlighted.

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Some have been studied in human as well as experimental models of the disease pathology.