Comparing Endovascular Revascularization to Open Surgical Revascularization for Chronic Mesenteric Ischemia

A Systematic Review and Meta-analysis

Abstract

Although the incidence of chronic mesenteric ischemia (CMI) is uncommon, it could become life threatening. With improvements in diagnostic imaging and endovascular therapy over the past few decades, the treatment of CMI has evolved. Even though endovascular revascularization for CMI is prominent, it is unclear if the early advantages outweigh the long-term patency rates. This study conducts a systematic review and meta-analysis to present comprehensive insights into the validity of endovascular revascularization versus open revascularization as effective therapeutic modalities. Studies up to 2022 were searched in MEDLINE, Cochrane Database of Systematic Reviews, Scopus, and Embase. Additionally, references from earlier studies and review papers were manually searched for additional relevant reports. At least two authors examined all the results, making sure they fit the inclusion and exclusion criteria. In the event of disagreement, the authors were able to reach an understanding. Open revascularization is superior to endovascular approaches in maintaining vessel patency and reducing symptoms over the long term. Perioperative problems are more common in patients undergoing open procedures. Each patient's anatomy and physiology call for a different revascularization approach to be applied in treating this condition.

INTRODUCTION

Most frequently, atherosclerotic narrowing of the celiac or superior mesenteric artery causes chronic mesenteric ischemia (CMI).[¹²] Nearly 18% of persons over 65 have extensive mesenteric atherosclerosis, yet the majority do not exhibit any symptoms.[³] Multispecialty consensus guidelines provide a Class I recommendation for endovascular therapy (percutaneous transluminal angioplasty with or without stenting) and open surgery (endarterectomy or bypass grafting) for the treatment of symptomatic disease.[⁴] To avoid cachexia and end-organ ischemia, which are linked to high mortality of 50%–69%,[⁵] it is crucial to treat the condition as soon as symptoms appear.

Due to the large collateral network of the visceral vessels, signs and symptoms of chronic occlusive visceral vascular illness can manifest mild or nonspecific symptoms for an extended period of time, which might delay the identification of acute onset CMI. Only 43% of patients with acute mesenteric ischemia experienced CMI symptoms in the past.[⁶] This makes a 35-month median latency to diagnosis in individuals with symptomatic CMI seem intolerably protracted and potentially disastrous.[⁷]

Recent decades have seen a rise in the diagnosis and treatment of CMI due to improvements in diagnostic imaging and endovascular capability.[⁸⁹] Revascularization rates for CMI have risen over time,[¹⁰] but there are no randomized data contrasting different revascularization approaches.

Over the past couple of decades, improvements in diagnostic imaging and endovascular therapy have allowed for a more nuanced approach to treating CMI. A current effective screening tool for visceral artery occlusive disease is mesenteric duplex ultrasound, but computed tomography arteriography has emerged as the definitive diagnostic study because it assesses the bowel and abdominal vasculature adequately.[¹¹]

Due to many lesions or poor general health, open surgical intervention can be challenging[¹²] and may result in complications such postoperative bleeding, cerebrovascular accidents, and anastomotic aneurysm.[¹³¹⁴] Contrarily, endovascular intervention has demonstrated positive short-term outcomes while being comparatively safe. On long-term patency following endovascular intervention, there are, however, little data.

Currently, duplex ultrasonography and computed tomography (CT) arteriography are more commonly used than catheter-based arteriography for the diagnosis of CMI. Due to earlier identification, intervening with less invasive endovascular technique to manage the CMI has increased dramatically concomitant with the advancements in visceral imaging.[⁹]

Given that the number of endovascular procedures carried out for CMI grew more than sevenfold (0.6–4.5/million; P < 0.01) between 2000 and 2012, the endovascular approach has essentially replaced the open surgical approach as the first-line treatment of CMI due to its reported decreased periprocedural morbidity and death rates.[⁸¹⁵¹⁶] Although the endovascular approach appears to have a higher risk of recurrent symptoms and the need for treatment, the improvement in the survival rate is still unclear.[¹⁷¹⁸]

Interestingly, Tallarita et al.[¹⁹] have demonstrated that the patient's comorbidities – rather than the type of procedure – predict survival after revascularization for CMI. Despite the widespread use of the endovascular approach, evidence-based standards have certain limitations on the quality of the supporting data, and it is unclear whether the early advantages of the endovascular approach outweigh the lower patency rates. According to Arya et al.,[²⁰] the morbidity and mortality of the open approach is low, although it enables a greater patency. The objective of this research is to investigate the validity of open and endovascular therapeutic interventions for CMI patients.

METHODOLOGY

Database and search strategy

Preferred Reporting Items for Systematic Reviews and Meta-Analyses criteria were followed for conducting this systematic review.[²¹²²] Studies up to 2022 were searched in MEDLINE, Cochrane Database of Systematic Reviews, Scopus, and Embase. The search term was (Chronic Mesenteric Ischemia) AND (Endovascular OR Open Surgical Revascularization) AND (Intervention OR Endovascular.) To find as many studies as feasible, the search was not language specific. Additionally, references from earlier studies and review papers were manually searched for additional relevant reports. At least two authors examined all the results, making sure they fit the inclusion and exclusion criteria. In the event of disagreement, the authors were able to reach an understanding.

Eligibility criteria

The enrolled studies must meet the inclusion criteria to be eligible. These criteria are (i) aiming to compare the endovascular and open surgical intervention, (ii) patients are diagnosed with a CMI, and (iii) information on patient numbers and outcome data. To prevent data duplication for numerous studies, published from the same health facility, only the most in-depth publication was considered.

The following criteria were used to exclude research: (i) overlapping or duplicated data, (ii) studies lacking reliability or validity, (iii) nonoriginal research articles, and (iv) studies with only an abstract available. There were no racial, ethnic, or geographical restrictions.

Data retrieval

An independent reviewer extracted data into a standardized, web-based form, which was then reconciled and sanitized. Study characteristics and methodological details were recorded. Data on outcomes of interest, including 30-day mortality, inhospital complications, postoperative recurrence in <3 years, and 3-year survival rate, were gathered with information on each intervention used.

Mortality at 30 days, postoperative complications, symptom improvement, and the necessity for a secondary procedure were all collected as outcomes. The average follow-up time was 5.5 months, and data were collected at 6 months, 1 year, 2 years, 3 years, and 5 years to determine the patency outcomes following surgery. One and three years after surgery, as well as during the median period of follow-up, patients reported a return of their symptoms. In addition to documenting symptom-free status at 1, 2, and 5 years after surgery, as well as over the mean follow-up period, the authors also noted that assisted primary patency was achieved at 1 and 5 years after surgery.

Data analysis

For this review, we pooled the data from all studies that met our inclusion criteria. Means were weighted. Overall results for open and endovascular operations were analyzed by treatment type, and a comparison of results and outcomes for each was made, as there have been notable methodological/technical improvements over the past two decades and a significant increase in the numbers of patients receiving endovascular procedures in the last decade. Categorical analysis was used to test for correlations, and results were presented as odds ratios (OR) with 95% confidence intervals (CI) or, in the case of 100% incidence variables, as absolute differences (values may be negative in these cases). A significant difference was determined to exist if P (<0.05). Microsoft Excel (version 2007; Microsoft Corp., Redmond, WA, USA) was used for the analyses, and the results were checked using SAS statistical software (version 9.1.3; SAS Institute, Cary, NC, USA).

RESULTS

Figure 1 shows the steps taken to select a research study. We started with a list of 1644 references and narrowed it down to 100 research (18,726 patients with CMI; 10,679 had undergone endovascular revascularization and 8047 had undergone an open surgical revascularization). Patients ranged in age from 9 to 99, with a median age of 69. Of the total population, 28% were male [Table 1]. As can be seen in Table 2, the prevalence of various cardiovascular risk factors among the study patients ranged widely; for example, patients had a smoking history and had hypertension. The majority of patients also complained of a decrease in weight and experienced abdominal pain.

Figure 1: Flowchart of the study selection of the systematic review and meta-analysis

Table 1: Characteristics of patients included in the meta-analysis studies

Table 2: Comparison of risk factors

Comparison of risk factors

In comparison to open surgery, endovascular therapy had a considerably greater rate of utilization between 2007 and 2014 (P < 0.001). There was an increase from 1433 to1845 annual endovascular procedures and from 417 to 520 annual surgical procedures. Patients (mean age: 69 years) with CMI were found to have abdominal pain as the primary symptom in 93.1% of the published literature over 20 years. Weight loss (76.1%), diarrhea (36.16%), nausea/vomiting (32.9%), and constipation (19.7%) were also common symptoms, while 84.3% of patients reported feeling pain after eating. Patients undergoing open surgeries [Table 2] had a higher prevalence of smoking and a lower prevalence of preexisting conditions such as diabetes, coronary artery disease, myocardial infarction, hypertension, hyperlipidemia, and renal insufficiency compared to patients undergoing laparoscopic procedures. Neither group differed significantly from the other in terms of age, angina, congestive heart failure, coronary artery bypass grafting, stroke, chronic obstructive pulmonary disease, hypercoagulability, or peripheral vascular disease.

Bias evaluation risk of the included studies

There were no randomized controlled trials to choose from (27 were comparative and 73 were noncomparative). There was a low risk of bias in most of the 27 meta-analyses when it came to the selection of research participants, the identification of exposure, the elimination of confounding factors, and the determination of outcomes. The perceived prejudice was relatively modest across the board. The 73 studies that did not compare outcomes had sufficient methodological quality. Only 27 studies were vetted for legitimacy [Table 3].[^{202324252627282930313233343536373839404142434445464748}]

Table 3: Bias evaluation risk of the included comparative studies

Outcomes of interest

Mortality rates at 30 days were higher for the open surgical intervention group [18 studies; respiratory rate (RR), 1.57; 95% CI, 0.84–2.93; Figure 2] compared to the endovascular group. However, this difference was not statistically significant.

Figure 2: Forest plot for outcome

There was a higher incidence of problems during hospitalization following open surgery [15 studies; RR, 2.19; 95% CI, 1.84–2.60; Figure 3]. Hematomas at the puncture site and embolization were more common with the endovascular method, while bowel resection and infections were more likely with the surgical method. Open surgery was linked with decreased incidence of 3-year recurrence (13 studies; RR, 0.47; 95% CI, 0.34–0.66). Open surgical surgery and endovascular technique yielded similar 3-year survival rates (13 studies; RR, 0.96; 95% CI, 0.86–1.07).

Figure 3: Forest plot for hospitalization

Noncomparative studies

The incidence rates for the outcomes of interest were reported for each intervention, but no comparisons were made between the studies. The overall quality of evidence was then deduced.

DISCUSSION

The goals of treating CMI are to alleviate the patient's symptoms, boost the patient's nutritional status, and stop the patient from suffering a visceral infarction. All patients with symptoms should be evaluated for visceral revascularization since the natural history of symptomatic CMI puts them at high risk for catastrophic gut infarction. Revascularization may be warranted in asymptomatic patients with severe occlusive disease of all three mesenteric arteries who are undergoing a simultaneous aortic operation for another indication, as has been suggested in a number of other papers (occlusive or aneurysmal disease).[⁴⁹]

The most efficient surgical treatment for CMI is still a matter of debate. Since Shaw and Maynard performed the first endarterectomy of the superior mesenteric artery in 1958, open surgery has remained the gold standard treatment. Percutaneous transluminal angioplasty and stenting, on the other hand, are now standard forms of endovascular surgery.

Endovascular intervention favors “early-stage” patients with CMI. However, because recanalizing the target vessel was impossible because of the severity of the calcification, only 67.7% of patients were considered technically successful. Treatment of CMI by the endovascular technique has improved during the study period, with higher technical success rates compared to earlier areas.

No randomized trials contrasting endovascular versus open surgery have been performed as of yet. However, endovascular revascularization is a feasible first line of treatment for almost all patients with CMI due to the reduced complication rates and rapid recovery associated with these treatments. This is especially true for patients whose stenosis in the affected veins is very short, meaning that angioplasty and stent implantation would not jeopardize a future landing location for an open bypass transplant. Patients with complex occlusive disease of the mesenteric vessels, patients in whom stent placement would jeopardize plausible subsequent bypass grafting (e.g., short celiac artery with significant disease), and patients who are technically unsuitable for endovascular procedures should still undergo open revascularization.

At high-throughput tertiary care center, three highly experienced interventional radiologists with specialized training in various visceral artery treatments performed all procedures (e.g., aneurysm and pseudoaneurysm treatment and hemorrhage treatment). In addition to the advantages of ET in terms of technical success, length of hospital stay, and morbidity, a backup complimentary to ET treatment for all patients was provided.

The nearly 19,000 patients were included in the 22 meta-analyses that compared trials and the 78 meta-analyses that did not compare studies. Compared to open revascularization, the endovascular method for CMI was related to decreased perioperative complication and mortality rates, but it was not as long lasting, as a higher symptom recurrence rate was observed at 3 years. Long-term survival at 3 years was comparable despite these variations in perioperative outcomes and recurrence rates.

Perioperative mortality was significantly higher in the CMI group (8% vs. 2%; RR, 1.57; 95% CI, 0.84–2.93), although this is to be expected given the complexity of the open surgery and the elderly, medically compromised nature of the CMI patient population. Given the 9%–13% mortality rates reported from the state and national administrative databases, it is somewhat unexpected that the mortality rate for the open repair was so low; this may indicate a publication bias for the open operations included in the review.[⁹]

Considering the types of complications commonly linked with the two methods, the difference in perioperative complications seen was unfavorable from the patient's perspective. The endovascular method may also be preferred as it enabled lesser durations in hospital stay, intensive care unit stay, discharge disposition, and transfusion need. Yet, these findings need to be augmented with unequivocal evidence inferred from large-scale cohorts.

Although this evaluation is the most thorough of its kind, our results are similar to those of previous meta-analyses comparing open and endovascular treatment for CMI.[^1017184950] Patency was significantly higher in the open group (OR, 3.57; 95% CI, 1.83–6.97; P < 0.0002), but there were no differences in perioperative morbidity, perioperative death, or survival. The endovascular group had a lower complication rate and a higher recurrence rate (8 trials, 569 cases), but Cai et al.[¹⁷] found no difference in perioperative mortality or survival.

Despite the similarity in perioperative mortality and survival, Gupta et al.[⁴⁹] reported that open repair was linked to a higher rate of postoperative complication, as well as higher 5-year primary patency (OR, 3.8; 95% CI, 2.4–5.8; P < 0.001). Moreover, the lack of recurrence of symptoms was greater (OR, 4.4; 95% CI, 2.8–7.0; P < 0.001).

Patients having endovascular versus open repair for CMI have shorter hospital and critical care unit stays, according to Zacharias et al.,[⁴⁸] whereas Indes et al.[¹⁵] found that a greater number of patients were discharged after the endovascular method.

Revascularization for CMI does not appear to affect long-term survival, as reported by Tallarita et al.[¹⁹] and Fidelman;[⁵¹] however, they did find that age >80 years, chronic kidney disease stages 4 and 5, and use of oxygen at home were predictors of all-cause mortality, and that death from mesenteric causes was remarkable in geriatric populations and medically compromised patients.

Hospital and overall care-related expenses for the treatment of CMI have not been widely compared to those for open versus endovascular repair of abdominal aortic aneurysms. Although the endovascular approach has a higher re-intervention rate, Hogendoorn et al.[⁵⁰] conducted a decision analysis comparing open and endovascular treatment of CMI and found that the endovascular strategy is more cost-effective across all age categories.

To conclude, the findings of this study are consistent with the mainstream that encourages opting for endovascular therapeutic interventions to treating CMI.[²⁷⁵¹]

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.