Mortality of acute mesenteric ischemia remains unchanged despite significant increase in utilization of endovascular techniques

Abstract

Introduction

In this study, we evaluated if increase in utilization of endovascular surgery has affected in-hospital mortality rates among patients with acute mesenteric ischemia.

Methods

The National Inpatient Sample (2003–2011) was queried for acute mesenteric ischemia using ICD-9 code for acute mesenteric ischemia (557.1). This cohort was divided into patients treated with open vascular surgery (open vascular group) and by endovascular therapies (endovascular group) based on the ICD-9CM procedure codes. Multivariable logistic regression was used to determine temporal trend for mortality while adjusting for confounding variables.

Results

There was 1.45-fold increase in utilization of endovascular techniques in this study. In-hospital mortality rate, total median charges and length of stay were significantly lower among the endovascular group than the open vascular group despite having significantly higher Elixhauser comorbidities index (3 ± 0.1 vs. 2.7 ± 0.1, p = .003). Over the course of the study period, there was no change in the overall mortality rate despite higher endovascular utilization. Factors associated with increased mortality included age, open surgical repair (Odds ratio: 1.45, 95% Confidence Interval: 1.10–1.91, p = .016) and bowel resection Odds ratio: 2.88, 95% Confidence Interval: 2.01–4.12).

Conclusion

The mortality rate for acute mesenteric ischemia remains unchanged throughout this contemporary study. Open surgical intervention, bowel resection and age were associated with increased mortality. Endovascular group patients had better survival despite higher morbidity indices.

Keywords

Acute mesenteric ischemia endovascular utilization mortality rates resources utilization

Introduction

Acute mesenteric ischemia (AMI) is difficult to diagnose based on clinical presentation alone due to similarity of AMI presentation to that of a myriad of different abdominal pathological conditions. There are not any pathognomonic clinical signs of AMI to distinguish it from other abdominal maladies with good reliability. Additionally, as AMI is an uncommon cause of presentation to emergency rooms,¹ lack of clinical suspicion often leads to delayed presentation, development of peritoneal signs with and subsequent staggeringly high mortality rates.^1–4

The current armamentarium at the disposal of vascular surgeons includes both open and endovascular techniques. As endovascular procedures are less invasive, endovascular therapies are often touted as procedures to decrease mortality. Perhaps the most impressive evidence of the efficacy of endovascular technique is in reducing the mortality rates after both elective and emergent procedures on abdominal aorta anerrysm.^5–7 A number of studies have also shown increased utility and improved survival among AMI patients treated by endovascular therapies.^3,4,8 Nevertheless, the impact of higher utilization of endovascular treatments on survival trends of AMI in contemporary endovascular era is lacking. The objects of this study were to identify factors that affect the mortality after AMI and whether the increased utilization of endovascular has affected the AMI mortality rates. In this regard, this study strives to evaluate if higher utilization of endovascular technology corresponded to a trend in decreasing mortality as it was previously suggested.⁸

Methods

In order to evaluate surgical outcomes for patients undergoing interventions for AMI in the United States we used the Nationwide Inpatient Sample (NIS) years 2003–2011. The NIS is the largest database of its kind and includes all-payer discharge information from a national survey of 20% of all non-federal hospitals in the US. A complete overview and description of the NIS is available on their website.⁹

The studied cohort was identified by linking the International Classification of Disease (ICD9-CM) procedure codes¹⁰ for all patient-discharges that occurred for the primary diagnosis of AMI (557.0). Only patients that had a revascularization procedure were included in this analysis. The open surgical group (OVG) included patients whose primary procedures were aortomesenteric or aortoceliac bypass (ICD9-CM: 39.26) and/or embolectomy of abdominal arteries (38.16) and/or incision of visceral artery (38.06).¹⁰ The endovascular group (EVG) included patients with ICD9-CM procedure codes of mesenteric angioplasty (39.50) and/or stenting (39.90) and/or infusion of thrombolytic agents (99.10) as their primary procedures. Patients with combined vascular and endovascular procedures and those who only had abdominal exploration were excluded. Forty-six discharges included combined endovascular and open procedures. The treatment cohorts were also divided into groups with or without bowel resection depending on the presence or absence of ICD9-CM procedure codes for bowel resection (45.70-9) (Figure 1).

The primary outcome measures for this retrospective study were to identify factors affecting mortality and whether there was a trend/change in postoperative in-hospital mortality rates after AMI for the overall cohort and for each procedure group (OVG, EVG). Secondary outcome measures included trends in bowel resection and resource utilization, namely hospital length of stay (LOS) and total hospital charges. Detailed procedure cost information is unavailable in the NIS therefore total hospital charges are used as a surrogate for cost information.

Bivariate comparison of categorical variables was performed using Chi square and continuous variables were compared using t-test. Multivariable logistic regression, which adjusts for confounding variables, was performed to determine whether there was a significant temporal change in hospital mortality. Covariates included in the logistic regression model were patient age, gender, insurance type, comorbid conditions (hypertension, diabetes mellitus (DM), chronic lung disease, coronary artery disease (CAD), congestive heart failure (CHF), valvular heart disease, obesity, renal failure), procedure type performed (open vs. endovascular) and bowel resection. The Elixhauser comorbidity SAS macro designed for use with administrative datasets was utilized to identify patient comorbidities for the purposes of bivariate and multivariable analyses.¹¹

The NIS provides a weighting strategy in order to draw estimates at the national level based on a 20% annual survey of hospitals. The statistical analyses were performed based on these weighted numbers and therefore the numbers provided in the results section are in the weighted format. This utilization of survey weights to make observations regarding surgical procedures at the national level is a method that has been previously utilized.^12,13

All statistical analyses were performed using SAS version 9.3 (Cary, North Carolina). For all tests a p < .05 was considered statistically significant.

Results

During the calendar years 2003–2011, we identified 42,154 patient discharges for AMI in the NIS sample. Of these, only 1563 had any invasive vascular procedures translating to a national weighted estimate of 7815 patients. The majority of patients were treated by endovascular procedures (EVG: 63.4% vs. 36.6%: OVG; p < 0.01). Table 1 contains national estimates of patient characteristics for the overall AMI population who underwent invasive vascular procedures.

Table 1.

Summary of the demographic differences between the open vascular group (OVG) and the endovascular group (EVG). The actual numbers are represented as ‘n’. Variables are summary of the weighted analyses.

Characteristic	Overall (n = 1563)	Endo group (n = 990)	Open group (n = 573)	p Value
Age
Mean ± SE	68.7 ± 0.4	68.5 ± 0.5	69.1 ± 0.5	0.397
Range	18–97	18–97	19–96
Gender:
Male	35%	36.7%	32.1%	<0.001
Female	65%	63.3%	67.9%	<0.001
Congestive heart failure	17.6%	18.6%	15.4%	0.017
Peripheral vascular disease	39.3%	45%	29.4%	<0.001
Hypertension	38.7%	40.7%	35.4%	<0.001
COPD	27.5%	28.7%	25.5%	<0.001
Diabetes w/complications	3%	3.4%	2.5%	0.349
Renal failure	8.9%	9.4%	7.9%	0.032
Elixhauser index	2.9 ± 0	3 ± 0.1	2.7 ± 0.1	0.008

Patient characteristics

There was an overall preponderance of female patients (65% vs. 35% male) with the gender compositions of the EVG and the OVG significantly different (p < 0.001) from one another. The OVG and the EVG patient groups were similar in age. With the exception of diabetes, all other recorded comorbidities were significantly higher in the EVG cohort. The Elixhauser's comorbidity index was significantly higher in the EVG (mean of 3 ± 0.1 vs. 2.7 ± 0.1, p = 0.003) (Table 1).

Bivariate analysis of patient postoperative mortality and the effect of bowel resection on in-hospital mortality

The total sample had an overall mortality rate of 17.7%. The mortality rate was significantly higher for OVG (21.9%) than EVG (15.3%; p < 0.001).

Overall 11.1% of the sample had bowel resection. Bowel resection was significantly more common among the OVG (14.9%) versus the EVG (9%, p < 0.001). The overall mortality in patients without bowel resection was 15.2%, which increased to 36% among patients undergoing bowel resection (Figure 2).

Bivariate analysis of LOS and median charges

The overall sample had a median LOS of 10 days and an associated median charge of $83000. LOS was significantly longer and median charges were significantly higher for OVG than EVG patients (both p < 0.001) (Figure 3). Bowel resection led to significant increases in LOS and charges for the overall sample and the two treatment groups. In the overall cohort of patients with bowel resection, LOS was 18 days and median charges were $147,588. Bowel resection led to similar increases in utilization in both treatment groups.

Multivariable analysis of in-hospital mortality and factors associated with bowel resection, LOS and charges

By multivariable logistic regression that adjusts for all the confounding variables, open surgery was independently associated with higher odds of mortality (Odds ratio (OR) 1.45; 95% Confidence Interval (CI) 1.10–1.91; p = 0.009) (Table 2). The other factor that was significantly associated with higher odds of postoperative mortality was bowel resection. Bowel resection was associated with increased odds of mortality for the overall sample (OR 2.88; 95% CI 2.01–4.12; p < 0.01), as well as for the OVG cohort (OR: 3.71; 95% CI: 2.28–6.04; p < 0.001) and the EVG sample (OR: 2.51; 95% CI: 1.50–4.18; p < 0.001) (Table 2). The year of the procedure did not independently affect mortality (OR: 1.03; 95% CI 0.98–1.08; p = 0.326) (Table 2). Similarly, the year of the procedure did not affect the mortality among the two treatment groups. Age was also an independent predictor of mortality (OR 1.65; 95% CI: 1.19–2.27; p = 0.002). The similar trend was noted among the EVG cohort but age was not independently associated with higher odds of mortality among the OVG (Table 2). History of peripheral vascular disease (PVD) was associated with decreased OR of mortality among the overall sample and the EVG cohort but this association was not significant among the OVG patients (Table 2).

Table 2.

Multivariable logistic regressions predicting odds of in-hospital mortality (columns overall, EVG and OVG) and bowel resection.

	Overall		EVG		OVG		Bowel resection
Contrast	OR (95%CI)	p Value	OR (95%CI)	p Value	OR (95%CI)	p Value	OR (95%CI)	p Value
Year	1.03 (0.98–1.08)	0.326	1.01 (0.94–1.08)	0.805	1.04 (0.97–1.12)	0.249	1.01 (0.89–1.15)	0.870
Age: 75 + vs. < 75	1.65 (1.19–2.27)	0.002	2.06 (1.33–3.20)	0.001	1.32 (0.80–2.17)	0.276	1.54 (0.74–3.20)	0.247
Female vs. Male	1.17 (0.88–1.56)	0.269	1.06 (0.73–1.56)	0.755	1.28 (0.80–2.03)	0.302	1.77 (0.94–3.34)	0.078
Medicare vs. private	1.46 (0.96–2.20)	0.074	1.61 (0.85–3.04)	0.143	1.39 (0.79–2.43)	0.252	1.35 (0.47–3.91)	0.579
Medicaid vs. private	0.93 (0.42–2.08)	0.858	1.17 (0.42–3.25)	0.770	0.78 (0.20–3.12)	0.730	0.30 (0.03–3.29)	0.326
Medicaid vs. Medicare	0.64 (0.29–1.38)	0.254	0.72 (0.28–1.91)	0.514	0.57 (0.15–2.13)	0.399	0.22 (0.02–2.03)	0.183
Elixhauser Index	1.03 (0.93–1.14)	0.606	1.08 (0.94–1.23)	0.276	0.95 (0.81–1.11)	0.526	0.92 (0.69–1.23)	0.569
PVD	0.59 (0.42–0.83)	0.003	0.41 (0.27–0.62)	<0.001	0.99 (0.57–1.72)	0.974	0.49 (0.19–1.29)	0.149
CHF	1.18 (0.83–1.68)	0.359	1.25 (0.80–1.95)	0.323	0.96 (0.53–1.74)	0.894	1.13 (0.48–2.66)	0.778
Diabetes	0.88 (0.60–1.27)	0.488	0.74 (0.46–1.19)	0.213	1.16 (0.65–2.07)	0.613	1.12 (0.40–3.12)	0.824
Weight loss	0.70 (0.48–1.03)	0.071	0.75 (0.44–1.27)	0.280	0.62 (0.34–1.12)	0.110	0.53 (0.22–1.30)	0.166
Bowel resection	2.88 (2.01–4.12)	<0.001	3.71 (2.28–6.04)	<0.001	2.51 (1.50–4.18)	<0.001
Open vs. Endo	1.45 (1.10–1.91)	0.009					0.87 (0.44–1.72)	0.691

EVG: endovascular group; OVG: open vascular group, CHF: congestive heart failure; PVD: peripheral vascular disease.

Factors that independently predict bowel resection are also depicted in Table 2. No association was noted between the year of the procedure and the type of procedure that was used for revascularization.

Tables 3 and 4 summarize the factors that independently increase LOS and total charges, respectively. The year of the procedure was independently associated with a decreased LOS among the overall cohort (β estimates: –0.02; 95% CI: –0.04 to –0.01; p = 0.10) and the EVG cohort (β: –0.03; 95% CI: –0.05 to 0.00; p = 0.02) but no significant association was noted among the OVG group (Table 3). Presence of preoperative weight loss, CHF, bowel resection and endovascular surgery were independently associated with increase in LOS (Table 3). History of PVD was associated with a decrease in LOS among the overall and treatment cohorts (Table 3). A significant association was noted between increasing total charges and the year of the procedure, presence of CHF, preop weight loss, bowel resection and the type of procedure (Table 4). Open surgery led to a significant increase in total charges (β: 0.28; 95%CI: 0.20–0.37; p < 0.001).

Table 3.

Multivariable regression analysis predicting length of stay (LOS).

Variable	Overall		EVG		OVG
Variable	Beta (95%CI)	p Value	Beta (95%CI)	p Value	Beta (95%CI)	p Value
Year	−0.02 (−0.04, −0.01)	0.010	−0.03 (−0.05,0.00)	0.022	−0.02 (−0.05,0.01)	0.182
Age: 75 + vs. < 75	−0.08 (−0.19, 0.03)	0.169	−0.14 (−0.28, 0.00)	0.050	0.02 (−0.15, 0.20)	0.789
Female vs. Male	−0.07 (−0.16, 0.02)	0.109	−0.09 (−0.21, 0.02)	0.109	−0.09 (−0.24, 0.05)	0.217
Medicare vs. private	−0.09 (−0.22, 0.04)	0.178	0.01 (−0.15, 0.17)	0.881	−0.25 (−0.43, −0.06)	0.008
Medicaid vs. private	0.09 (−0.14, 0.32)	0.448	0.15 (−0.15, 0.44)	0.338	−0.10 (−0.47, 0.28)	0.612
Medicaid vs. Medicare	0.18 (−0.05, 0.4)	0.123	0.13 (−0.16, 0.42)	0.371	0.15 (−0.22, 0.51)	0.425
Elixhauser Index	0.01 (−0.03, 0.04)	0.655	0.05 (0.00, 0.09)	0.044	−0.06 (−0.12, −0.01)	0.032
PVD	−0.20 (−0.3, −0.11)	<0.001	−0.22 (−0.34, −0.10)	<0.001	−0.22 (−0.39, −0.06)	0.007
CHF	0.27 (0.16, 0.39)	<0.001	0.21 (0.06, 0.36)	0.006	0.33 (0.16, 0.51)	<0.001
Diabetes	−0.03 (−0.16, 0.09)	0.582	−0.04 (−0.18, 0.11)	0.621	−0.07 (−0.29, 0.16)	0.560
Weight loss	0.57 (0.46, 0.68)	<0.001	0.64 (0.49, 0.79)	<0.001	0.47 (0.32, 0.63)	<0.001
Bowel resection	0.34 (0.20, 0.48)	<0.001	0.40 (0.21, 0.59)	<0.001	0.28 (0.08, 0.48)	0.005
Open vs. Endo	0.49 (0.39, 0.58)	<0.001

EVG: endovascular group; OVG: open vascular group, CHF: congestive heart failure; PVD: peripheral vascular disease.

Table 4.

Multivariable regression analysis predicting total charges.

Variable	Overall		EVG		OVG
Variable	Beta (95%CI)	p Value	Beta (95%CI)	p Value	Beta (95%CI)	p Value
Year	0.07 (0.06, 0.09)	<0.001	0.08 (0.05, 0.10)	<0.001	0.07 (0.04, 0.10)	<0.001
Age: 75 + vs. < 75	−0.13 (−0.23, −0.03)	0.010	−0.15 (−0.27, −0.04)	0.009	−0.09 (−0.26, 0.08)	0.301
Female vs. male	0.00 (−0.08, 0.08)	0.999	0.00 (−0.10, 0.10)	0.990	−0.05 (−0.18, 0.09)	0.517
Medicare vs. private	−0.09 (−0.20, 0.02)	0.125	−0.03 (−0.17, 0.10)	0.613	−0.16 (−0.35, 0.03)	0.098
Medicaid vs. private	−0.03 (−0.23, 0.18)	0.791	0.04 (−0.20, 0.28)	0.741	−0.26 (−0.63, 0.11)	0.171
Medicaid vs. Medicare	0.06 (−0.13, 0.25)	0.524	0.07 (−0.16, 0.31)	0.529	−0.10 (−0.44, 0.24)	0.571
Elixhauser Index	−0.03 (−0.06, 0.00)	0.093	0.00 (−0.04, 0.04)	0.976	−0.08 (−0.14, −0.02)	0.005
PVD	−0.21 (−0.29, −0.13)	<0.001	−0.26 (−0.36, −0.15)	<0.001	−0.15 (−0.30, 0.00)	0.051
CHF	0.25 (0.15, 0.36)	<0.001	0.22 (0.09, 0.35)	0.001	0.29 (0.11, 0.47)	0.001
Diabetes	−0.04 (−0.15, 0.06)	0.427	−0.03 (−0.15, 0.09)	0.587	−0.10 (−0.32, 0.11)	0.335
Weight loss	0.43 (0.32, 0.54)	<0.001	0.40 (0.27, 0.54)	<0.001	0.48 (0.31, 0.66)	<0.001
Bowel resection	0.48 (0.36, 0.60)	<0.001	0.56 (0.42, 0.70)	<0.001	0.41 (0.23, 0.60)	<0.001
Open vs. Endo	0.28 (0.20, 0.37)	<0.001

EVG: endovascular group; OVG: open vascular group; CHF: congestive heart failure; PVD: peripheral vascular disease.

Trends in mortality and bowel resection

From 2003 to 2011, the utilization of endovascular procedures had significantly increased. In 2003, 48.9% of mesenteric revascularizations were performed by endovascular methods. By 2011, this rate was increased to more than 72%, an increase of 1.45-folds. Despite this increase in utilization of endovascular technology, rates of bowel resection (Figure 2) and mortality (Figure 3) remained statistically unchanged. Year as an independent variable was not associated with either the mortality rate or the bowel resection rate as noted above in multivariable analyses.

Discussion

In this retrospective observational study of contemporary national data (2003–2011) we have found that utilization of endovascular techniques have increased by 1.45-folds for treatment of patients with AMI with the endovascular procedures composing the majority of cases towards the end of the study period. Compared to the EVG, the OVG patients had significantly higher rates of in-hospital mortality (21.9% vs. 15.3%; p = .001) and bowel resection (14.9% vs. 9%; p < 0.001). By multivariable analysis, age and open surgery as well as bowel resection were independently associated with higher odds of in-hospital mortality. In terms of resources utilization, median total hospital charges and median LOS were significantly higher in the OVG than in the EVG (p < .0001 for both analyses). Open procedure (vs. endovascular) and presence of bowel resection (vs. no bowel resection) independently increased both LOS and total charges. Despite higher utilization of less invasive endovascular techniques, this study showed no trend in decreasing the mortality rate or rate of bowel resection.

The overall mortality rates after AMI have been reported to be staggeringly high. Mortality rates of 60–80% have been reported,^1,2 which is thought to be mainly related to delay in diagnosis and long duration of mesenteric ischemia. Early diagnosis and shorter duration of mesenteric ischemia have been shown to significantly decrease mortality rates due to AMI.¹⁴ In a recent analysis, Beaulieu et al.⁴ showed that in-hospital mortality rates due to mesenteric ischemia remained high. In our study, the overall in-hospital mortality rate due to AMI (17.7%) is quite comparable to mortality rate reported in the study by Schermerhorn et al.,⁸ which was less than reported by Beaulieu et al.⁴ The differences between the mortality rates reported here and in Beaulieu may stem from our methodology. Unlike Beaulieu et al.,⁴ in our analysis, we only included patients with AMI who had either open or endovascular revascularization and excluded those who did not have vascular revascularization, e.g. patients who were explored only (Figure 1). Among patients who had bowel resection, nonetheless, the mortality rates of our sample was similar to Beaulieu et al.⁴ Our results were comparable to the contemporary mortality rates of a single institution study¹⁵ where authors reported a 17% mortality rate after AMI in 2000s. In that regard this study serves not only to further update the findings of the previous studies but also validates the previously utilized ICD9-CM–based coding methodology.

The observation in the current work that AMI patients who underwent open surgery had a 1.45-fold higher in-hospital mortality rates than the endovascular patients is similar to other studies.^3,4,8 In this administrative database, it is difficult to appropriately compare the two groups since anatomical data and clinical information are missing. We can speculate that the EVG group may include group of patients with less degree of mesenteric ischemia. Beaulieu et al.,⁴ for example, have shown that the patients with open surgery in the NIS sample had higher percentage of lactic acidosis and ARDS and may have been “preferentially” treated by open surgery.⁴ It is, therefore, not possible to appropriately compare the two cohorts without conducting a randomized prospective trial of AMI patients, something that is unlikely to be completed due to the rarity of the condition and the degree of extremis of these patients. In the interim, other measures of adequacy of performance between the two procedures have been evaluated such as economic outcomes including LOS data and cost information.

The current work found that for patients undergoing endovascular revascularization for AMI, there is a significant difference in hospital LOS and median charges. Overall, open surgery was associated with significantly greater median total hospital charges ($101762) than EVG ($73,317, p < 0.001). Bowel resection increased the overall costs by more than $50,000. To our knowledge, this is the first study to evaluate total charges for open revascularization and endovascular therapy for AMI at the national level. Multivariable analyses also suggested that open surgery and presence of bowel resection independently increased LOS and total charges.

Despite significant increases in utilization of endovascular approach (such as clot evacuation techniques, recanalization etc.), and significant survival advantages among the EVG, our study showed no statistically significant trend in decreasing the overall mortality for patients treated for AMI in the US from 2003 to 2011. In the work presented here the overall mortality rates were significantly better than previously reported rates of 50–80%.^2,3,14,16 But our work suggests that even though majority of these procedures were performed using endovascular procedures, the mortality rates have remained unchanged in the last decade. This finding is dissimilar to Schermerhhorn et al.⁸ publication that suggested a trend of decrease in mortality between procedures after and before 2000.⁸ In our study the overall mortality rate did not significantly decrease and we did not observe a decreasing trend in mortality. Additionally, in our study, bowel resection rates were stable as well. As bowel resection is a significant predictor of mortality, this may be another reason that despite endovascular advances and adoption of endovascular techniques, the mortality rate has remained unchanged. One major difference between the results here and what was reported by Schermerhorn et al.⁸ is that the latter evaluated almost a 20-year span with significant differences in technology used during the study span to treat vascular patients. The lack of significant contrast in the utilization of endovascular procedures and bowel resection rates throughout our study period compared to Schermerhorn et al.⁸ most likely accounts for stable mortality rates.

The limitations of studies based on administrative datasets such as the NIS have been described previously.¹⁷ Coding inaccuracies in terms of patient case-mix, such as prevalence of comorbidities, or in reporting the primary vs. secondary procedures are possible. To minimize these inaccuracies we used established comorbidity software to attempt to appropriately characterize patients with pre-existing comorbid conditions.¹¹ Additionally, in-hospital outcomes are a sub-optimal measure of overall success when evaluating surgical interventions. Ideally long-term information such as 30-day and 1-year mortality rates would be better to evaluate mortality. However due to the arduous patient de-identification process employed by the NIS, follow-up information is unavailable. Similarly, total hospital charges as a marker of economic impact of a surgical procedure provides only crude information and therefore in this study is used as a surrogate for cost information and conclusions should be drawn with this fact in mind. Previous works have utilized this total hospital charge information¹⁸ which was corroborated with institutional studies and mitigates this limitation to some degree suggesting that the hospital charges is a reasonable surrogate of procedure costs.

Our study suggests that the utilization of endovascular approaches to AMI have surpassed open surgical revascularization. Our study cannot distinguish between antegrade and retrograde endovascular approaches, as there are no unique ICD9 codes with retrograde approach. The proven efficacy of the hybrid retrograde approach¹⁹ in treatment of AMI in such settings may prove advantageous over purely open or endovascular revascularization procedures. With the increasing prevalence of hybrid operating rooms, revascularization via retrograde approach may be attempted first before embarking on complicated open revascularization in these often very hemodynamically compromised patients. This may eventually prove to be the key in decreasing mortality in patients with AMI.

Conclusion

From the year 2003–2011, and within the limitations of a large administrative dataset, we have shown that endovascular utilization for treatment of AMI has increased. Further, the EVG has advantages in the mortality rates, resources utilization and the rates of bowel resection when compared with the OVG. Despite this increase in the utilization of endovascular techniques, in this contemporary analysis, we observed no trend in improvement of the mortality rates or the bowel resection rates.

Footnotes

Declaration of conflicting interests

The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Funding

The author(s) received no financial support for the research, authorship, and/or publication of this article.

Acknowledgement

This work was previously presented at the 27th Eastern Vascular Society Annual Meeting, White Sulphur, WA, September 2013.

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