Table of Contents  
ORIGINAL ARTICLE
Year : 2022  |  Volume : 9  |  Issue : 4  |  Page : 296-301

Perioperative outcomes of open surgical repair for juxtarenal and infrarenal aortoiliac occlusive disease in patients with poor cardiac status


Department of Vascular Surgery, Madurai Medical College, Madurai, Tamil Nadu, India

Date of Submission26-Jun-2022
Date of Decision08-Aug-2022
Date of Acceptance24-Aug-2022
Date of Web Publication8-Nov-2022

Correspondence Address:
Sudharsan Reddy Yalamuru
Department of Vascular Surgery, Madurai Medical College, Madurai, Tamil Nadu
India
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Source of Support: None, Conflict of Interest: None


DOI: 10.4103/ijves.ijves_37_22

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  Abstract 


Purpose: The most common cause of mortality in patients undergoing open surgical repair for aortoiliac disease is from cardiac complications. As there is a paucity of literature about the surgical outcomes in patients with compromised cardiac status, this study was undertaken to study the perioperative outcomes of open surgical repair for aortoiliac occlusive disease in patients with poor cardiac status. Methodology: A retrospective study was carried out from January 2017 to December 2020. Patients with aortoiliac occlusive disease based on computed tomography angiographic findings with poor cardiac reserve (ejection fraction ≤40% on echocardiography) were included in the study. The primary endpoints were perioperative complications which included intraoperative hemodynamic complications and early postoperative complications. Results: During 2017–2020, a total of 44 patients with aortoiliac occlusive disease (AIOD) with erectile function ≤40% underwent open surgical repair. Of these, 25 (57%) patients had infrarenal aortoiliac involvement and 19 (43%) had juxtarenal aortoiliac involvement. In our study of open surgical repair for juxtarenal and infrarenal aortoiliac occlusive disease in patients with poor cardiac status, intraoperative hemodynamic complications were noted in 26 (59%) patients, early postoperative complications were noted in 11 (25%), and mortality rate was 4.5%. Conclusion: Even though AIOD patients with poor cardiac status are at high operative risk than patients with normal cardiac status, open surgical repair with in-line bypass can be considered as a suitable option in these patients, especially where facilities for appropriate intraoperative monitoring and management are available.

Keywords: Aortoiliac disease, open surgical repair, poor cardiac status


How to cite this article:
Balaji S K, Robinson C S, Yalamuru SR, Kumar SG, Maruthupandian AK, Ahmed SM, Bharat Arun M V, Ray R. Perioperative outcomes of open surgical repair for juxtarenal and infrarenal aortoiliac occlusive disease in patients with poor cardiac status. Indian J Vasc Endovasc Surg 2022;9:296-301

How to cite this URL:
Balaji S K, Robinson C S, Yalamuru SR, Kumar SG, Maruthupandian AK, Ahmed SM, Bharat Arun M V, Ray R. Perioperative outcomes of open surgical repair for juxtarenal and infrarenal aortoiliac occlusive disease in patients with poor cardiac status. Indian J Vasc Endovasc Surg [serial online] 2022 [cited 2022 Nov 28];9:296-301. Available from: https://www.indjvascsurg.org/text.asp?2022/9/4/296/360543




  Introduction Top


Epidemiologic studies have estimated that more than 200 million individuals are currently affected by peripheral arterial disease (PAD) worldwide.[1] PAD has been divided into the aortoiliac, femoropopliteal, and tibiopedal segments anatomically. The aortoiliac segment is one of the most commonly involved areas, with epidemiologic studies demonstrating significant aortoiliac atherosclerosis in over half of patients with symptomatic PAD.[2] These patients can present with claudication of gluteal, thigh, and calf compartments or with chronic limb-threatening ischemia (CLTI) (rest pain or tissue loss). Leriche syndrome, a unique manifestation of aortoiliac disease, is characterized by gluteal claudication, impotence, and absent femoral pulses.

Patients presenting with intermittent claudication are managed with risk factor modification, best medical therapy (antiplatelet agents, statins) and supervised exercise program. Revascularization is indicated in patients presenting with CLTI. Most aortoiliac lesions can be treated using an endovascular approach, frequently using bare metal or covered stents, while surgery is reserved for extensive occlusions or after failed endovascular procedures.[3],[4],[5]

Surgical options include aortoiliac endarterectomy and aortobifemoral bypass (ABFB). The 5-year patency rate of ABFB is 85%–90%.[6] Morbidity rates reported after aortoiliac surgery range from 17% to 32%.[7] Myocardial infarction (MI) is reported in up to 1%–5% of them.[7] In patients undergoing aortoiliac surgery, cardiac complications are the most common cause of mortality, which result from the hemodynamic stress associated with major vascular surgery and the obligatory fluid shifts during the early postoperative period in these patients.[8] Another factor which makes these patients at risk for surgery is preexisting cardiac disease. Coronary artery disease (CAD) is highly prevalent in vascular surgical patients. Hertzer et al. showed that only small percentage of vascular surgery patients (8%) were free of CAD.[9]

In view of high prevalence of coronary involvement among PAD patients and with fewer studies currently available on the surgical outcomes in patients with compromised cardiac status, we undertook this research to study the perioperative outcomes of open surgical repair for aortoiliac occlusive disease in patients with poor cardiac status.


  Methodology Top


This was retrospective study conducted over a period of 4 years from January 2017 to December 2020. Data of patients diagnosed to have aortoiliac occlusive disease (AIOD) based on computed tomography angiogram report, during the above-mentioned period, was collected. Aortoiliac occlusive disease was defined as Infra renal disease – i.e., without involvement of the origin of the inferior mesenteric artery (IMA) or juxtarenal disease-where disease extends cephalad to IMA, approaching the level of the renal arteries.[10] Inclusion criteria were as follows: patients with AIOD who underwent open surgical repair with poor cardiac reserve (ejection fraction ≤40% on echocardiogram), and exclusion criteria were as follows: AIOD patients with GOLD4 criteria on pulmonary function test (PFT) and patients who underwent extra-anatomic bypass.

All patients satisfying the above inclusion and exclusion criteria were included in the study, and details regarding demographics, clinical history, examination findings, preoperative investigations (echocardiography [ECHO] and PFT findings), surgical procedure, and intraoperative and postoperative events were collected from the records.

Surgical procedure

All patients underwent transperitoneal approach for AIOD. Infrarenal aortic exposure is performed by retracting the transverse colon cephalad and the small bowel to right side after dividing the ligament of Treitz, and dissecting the retroperitoneal tissue over the aorta. For disease limited to the infra-aortic segment, infrarenal clamping of aorta was done after systemic heparinization. Aorta was transected proximal to IMA origin and endarterectomy was done. Using Dacron graft, aortobifemoral bypass was done with end-to-end anastomosis proximally and graft tunnelled retroperitoneally anterior to native vessels and posterior to ureters [Figure 1], [Figure 2], [Figure 3], [Figure 4]. In patients with occluded or severely diseased external iliac arteries but with patent common and internal iliac arteries, end to side anastomosis was done to preserve pelvic perfusion via internal iliac arteries. In patients with juxtarenal occlusion, supra renal aortic clamping was done along with clamping of bilateral renal arteries. Prior to clamping, diuresis was done with mannitol. Clamp shifted infrarenally after endarterectomy of transected aorta. The average warm ischemia time was around 10 min. Hypertension encountered after Aortic clamping was managed with vasodilators & short acting beta blockers whereas hypotension seen after aortic declamping was managed with IV fluids and inotrope support.
Figure 1: Infrarenal AIOD. AIOD: Aortoiliac occlusive disease

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Figure 2: Juxtarenal AIOD. AIOD: Aortoiliac occlusive disease

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Figure 3: Exposure of infrarenal aorta

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Figure 4: Proximal anastomosis with Dacron bifurcation graft

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The primary endpoints were perioperative complications, which included intraoperative hemodynamic complications and early postoperative complications [Table 1]. Intra-operative data collected included details of management of Blood pressure fluctuations (i.e., Use of more than one inotrope for hypotension control after declamping), new regional wall motion abnormalities, change in Ejection fraction by intra-operative Echo monitoring, development of pulmonary edema, ECG changes and Arterial blood gas (ABG) analysis. Details collected in the early post-operative period (up to 30 days following procedure) included - Cardiac complications (Acute coronary syndrome, congestive heart failure, arrhythmias), Pulmonary events (Atelectasis, Pneumonia, Pulmonary edema, Acute respiratory failure, Transfusion related acute lung injury), Renal – Acute kidney injury, Bowel ischemia, Spinal cord Ischemia and death.
Table 1: Primary endpoints 1: Intraoperative hemodynamic complications, 2: Early postoperative complications

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Statistical analysis

Data were given as mean, standard deviation (SD), and interquartile range for continuous data and as frequency for categorical data. Inferential data were assessed and P value was calculated through t-test for raw data and Chi-square test for consolidated data. Results from the analysis were expressed as P value with a 95% confidence interval. P < 5% was considered statistically significant. Statistical analysis was performed using IBM Corp. released 2007. IBM SPSS Statistics for Windows, Version 16.0. (Armonk, NY: IBM Corp).


  Results Top


The total number of AIOD patients treated during 2017–2020 was 108. Of these, patients satisfying the inclusion and exclusion criteria were 44. 25/44 (57%) patients had infrarenal AIOD, which included 23 males and 2 females. 19/44 (43%) patients had juxtarenal AIOD and all were male. The mean age of the study population was 53.51 years (SD: 9.16) and the range was 48 years (75–27). Out of 44 patients, 40 (90%) had smoking history. In the study population, 25 (56.8%) had diabetes, 16 (36.3%) had hypertension, and 19 (43.1%) had pulmonary disease (chronic obstructive pulmonary disease, past tuberculosis, and bronchial asthma). Forty-two (95.45%) patients had CAD and 2 (4.54%) patients had dilated cardiomyopathy. The mean ejection fraction (SD) was 34.23 (3.45) [Figure 5]. Demographic details are depicted in [Table 2].
Figure 5: Distribution of ejection fraction

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Table 2: The study population

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Intraoperative hemodynamic complications

All 44 patients underwent transperitoneal approach for open surgical repair. In the infra renal group 5 patients developed acidosis, 6 patients developed hypotension which was treated with dual inotropic support, 2 patients developed pulmonary edema and 2 patients had ventricular premature contractions. In the Juxta renal group 4 patients developed acidosis, 4 patients required dual inotropes to treat hypotension and pulmonary edema, ventricular premature contractions and a decrease of ejection fraction by 11.1% were seen in 1 patient each [Figure 6]. Intra-Operative hemodynamic complications were noted in 15 out of 25 (60%) subjects in Infra Renal group and in 11 out of 19 patients (57.8%) of Juxta Renal group; accounting to 26 out of 44 patients totally (59%) [Table 3]. There was no statistically significant difference among two groups with respect to intraoperative hemodynamic complications (P = 0.8845). The average (SD) estimated blood loss was 579 ml (179) and the range was 700 ml (1000–300).
Figure 6: Intraoperative hemodynamic complications

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Table 3: Intraoperative details

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Early postoperative complications were noted in 11/44 subjects (25%) [Table 4] and [Figure 7]. In infrarenal group three patients developed pulmonary complications and one patient having dilated cardiomyopathy and EF – 28% expired on Post-operative day (POD) - 2 due to Myocardial infarction (MI). In the juxtarenal group one patient died due to MI on POD -1 (Known CAD patient with EF-32%), 3 patients suffered pulmonary complications and one patient had acute renal failure in the early post-operative period. The pre-op S.Creatinine for this patient was 1.2mg/dl which rose to 4.6mg/dl postoperatively. Overall, early postoperative complications were seen in 20% of the infrarenal group and 31.5% of the juxtarenal group, and the difference was statistically insignificant (P = 0.3881).
Table 4: Early postoperative complications

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Figure 7: Early postoperative complications in both groups

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  Discussion Top


Patients with PAD have a high chance of having involvement of other arterial territories. Criqui demonstrated that individuals with asymptomatic PAD had a 5.6-fold greater risk of CAD-related death.[12] Over 5 years, approximately 20% of patients with claudication will experience a major cardiovascular event and mortality ranges between 10% and 15%.[13],[14] Patients with CLTI are at even higher risk for cardiovascular events, as many as 25% of these patients die of cardiovascular complications within 1 year.[15] Moreover, in patients undergoing aortic surgery, cardiac complications are the most common cause of mortality,[8] and preexisting cardiac disease further increases this risk.[16]

In our study, 44 patients with ejection fraction less than or equal to 40% underwent open surgical repair for aortoiliac occlusive disease. Overall intraoperative hemodynamic complications were noted in 15 out of 25 (60%) subjects in the infrarenal group and in 11 (57.8%) out of 19 patients of the juxtarenal group, accounting to 26 (59%) out of 44 patients. In the infrarenal group, five patients developed acidosis, six patients required dual inotropes for hypotension correction, two patients developed pulmonary edema, and ventricular premature contractions were noted in two patients. In the Juxta renal group 4 patients developed acidosis, 4 patient's required dual inotropes to treat hypotension after declamping and pulmonary edema, ventricular premature contractions and a decrease of ejection fraction by 11.1% were seen in one patient each. The patient in Juxta renal group with intra operative fall in ejection fraction by 11.1% had pre-operative EF -36% and intra operative EF -32%. This patient was managed with antiplatelet drugs and anticoagulation alone without coronary intervention as the patient was asymptomatic. Echocardiogram repeated after 5 days showed improvement in ejection fraction to preoperative level. With respect to intraoperative hemodynamic complications, there was no statistically significant difference among two groups (P = 0.8845).

In general, the cardiovascular response to infrarenal aortic cross-clamping is less significant than with high aortic cross-clamping and several clinical reports have noted no significant hemodynamic response to infrarenal cross-clamping.[17] This high incidence of intraoperative hemodynamic complications noted in our study can be due to impaired ventricular response to changes in preload and afterload associated with aortic clamping and unclamping. Levin in his study stated that the hemodynamic responses to aortic clamping and unclamping are more pronounced in patients with low cardiac reserve than patients with normal cardiac status.[18] Various other studies also have confirmed that patients with severe left ventricular dysfunction are bound to have significantly elevated hemodynamic complications upon infrarenal aortic cross-clamping and increased incidence of segmental wall motion abnormalities on echocardiography.[19]

In our study, early postoperative complications were noted in 11 (25%) and mortality rate was 4.5%. Bredahl et al.[20] in their study identified 30-day mortality of 3.6% and the 30-day major complication rate of at 20%. Other studies also have showed similar post-operative morbidity rates ranging from 17% to 32% after aortic surgery for occlusive disease[7] and several large meta-analyses noted an overall 30-day mortality rates between 4.0% and 4.4%.[21],[22],[23]

The incidence of postoperative MI in our study was 4.5%. Bertges et al. in their study noted the incidence of postoperative MI after aortic surgery to be 3.1%–4.3%.[24] In the juxtarenal group one patient had acute renal failure in the early post-operative period (pre-op S.Creatinine was 1.2mg/dl which rose to 4.6mg/dl postoperatively) and was managed with alternate day Haemodialysis for 3 weeks following which the renal function returned to baseline after 3 weeks. The incidence of transient need for dialysis in our study was 2.2%, which was comparable to the incidence in other reported studies, Breckwoldt et al.[25] (2.6% transient and 0% persistent) and Qvarfordt et al.[26] (2.5% transient).

It is widely believed that axillobifemoral bypass is physiologically less stressful than aortobifemoral bypass in high-risk patients, yet reported operative mortality rates range from 1.7% to 16% after axillobifemoral bypass[27],[28],[29],[30],[31] with patency rates being inferior to aortobifemoral bypass.[28],[29],[30],[31]

In our study, even though there is an increased incidence of intraoperative hemodynamic complications in this subset of AOID patients with low ejection fraction, it did not translate into increased morbidity or mortality postoperatively as the observed early postoperative morbidity and mortality rates were comparable to the reported outcomes of ABFB for occlusive disease and had comparable mortality rates to extra anatomical bypass surgery. Combined with appropriate intraoperative monitoring, management, and meticulous surgical technique, open surgical repair with in-line bypass can be considered in AIOD patients with poor cardiac status.


  Conclusion Top


Even though AIOD patients with poor cardiac status are at high operative risk than patients with normal cardiac status, open surgical repair with in-line bypass can be considered a suitable option in these patients, especially where facilities for appropriate intraoperative monitoring and management are available.

Limitations

A Larger study population and a longer follow up period could have been more helpful in understanding of the outcomes of in-line open surgical repair in patients with poor cardiac status and also using a standardised cardiac risk stratification criteria, could have better defined the poor cardiac performance.

Acknowledgment

We acknowledge the Department of Anaesthesiology, Madurai Medical College, Madurai.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.



 
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    Figures

  [Figure 1], [Figure 2], [Figure 3], [Figure 4], [Figure 5], [Figure 6], [Figure 7]
 
 
    Tables

  [Table 1], [Table 2], [Table 3], [Table 4]



 

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