Effects of Iliac Tortuosity Index on Fenestrated Endovascular Aortic Aneurysm Repair for Pararenal and Thoracoabdominal Aortic Aneurysms

PURPOSE

To evaluate the effect of iliac tortuosity on procedural metrics and outcomes of patients with complex aortic aneurysms (cAAs) undergoing repair with fenestrated/branched endografts (f/b-EVAR [endovascular aortic aneurysm repair]).

MATERIAL AND METHODS

The study is a single-center, retrospective review of a prospectively maintained database of patients undergoing aneurysm repair using f/b-EVAR between the years 2013 and 2020 at our institution. Included patients had at least 1 preoperative computed tomography angiography (CTA) available for analysis. Iliac artery tortuosity index (TI) was calculated using centerline of flow imaging from a 3-dimensional work station based on the formula: (centerline iliac artery length / straight-line iliac artery length). The associations between iliac artery tortuosity and procedural metrics, including total operative time, fluoroscopy time, radiation dose, contrast volume, and estimated blood loss (EBL), were evaluated.

RESULTS

During this period, 219 patients with cAAs underwent f/b-EVAR at our institution. Ninety-one patients (74% men; mean age = 75.2±7.7 years) met criteria for inclusion into the study. In this group, there were 72 (79%) juxtarenal or paravisceral aneurysms and 18 (20%) thoracoabdominal aortic aneurysms and 5 patients (5.4%) with failed previous EVAR. The average aneurysm diameter was 60.1±0.74 mm. Overall, 270 vessels were targeted, and 267 (99%) were successfully incorporated, including 25 celiac arteries, 67 superior mesenteric arteries, and 175 renal arteries. The mean total operative time was 236±83 minutes, fluoroscopy time was 87±39 minutes, contrast volume was 81±47 mL, radiation dose 3246±2207 mGy, and EBL was 290±409 mL. The average left and right TIs for all patients were 1.5±0.3 and 1.4±0.3, respectively. On multivariable analysis, the interval estimates suggest positive association between TI and procedural metrics to a certain degree.

CONCLUSIONS

In the current series, we found no definitive association between iliac artery TI and procedural metrics, including operative time, contrast used, EBL, fluoroscopy time, and dose in patients undergoing cAA repair using f/b-EVAR. However, there was a trend toward association between TI and all these metrics on multivariable analysis. This potential association needs to be evaluated in a larger series.

CLINICAL IMPACT

Iliac artery tortuosity should not exclude patients with complex aortic aneurysms from being offered fenestrated or branched stent graft repair. However, special considerations should be taken to mitigate the impact of access tortuosity on alignment of fenestrations with target vessels, including use of extra stiff wires, through and through access and delivering the fenestrated/branched device into another (larger) sheath such as a Gore DrySeal in patients with arteries large enough to accommodate such sheaths.

The role of IGF-pathway biomarkers in determining risks, screening, and prognosis in lung cancer

Background: Detection rates of early-stage lung cancer are traditionally low, which contributes to inconsistent treatment responses and high rates of annual cancer deaths. Currently, low-dose computed tomography (LDCT) screening produces a high false discovery rate. This limitation has prompted research to identify biomarkers to more clearly define eligible patients for LDCT screening, differentiate indeterminate pulmonary nodules, and select individualized cancer therapy. Biomarkers within the Insulin-like Growth Factor (IGF) family have come to the forefront of this research.

Main Body: Multiple biomarkers within the IGF family have been investigated, most notably IGF-I and IGF binding protein 3. However, newer studies seek to expand this search to other molecules within the IGF axis. Certain studies have demonstrated these biomarkers are useful when used in combination with lung cancer screening, but other findings were not as conclusive, possibly owing to measurement bias and non-standardized assay techniques. Research also has suggested IGF biomarkers may be beneficial in the prognostication and subsequent treatment via systemic therapy. Despite these advances, additional knowledge of complex regulatory mechanisms inherent to this system are necessary to more fully harness the potential clinical utility for diagnostic and therapeutic purposes.

Conclusions: The IGF system likely plays a role in multiple phases of lung cancer; however, there is a surplus of conflicting data, especially prior to development of the disease and during early stages of detection. IGF biomarkers may be valuable in the screening, prognosis, and treatment of lung cancer, though their exact application requires further study.

A Review of Antithrombotic Therapies for Patients with Chronic Peripheral Arterial Disease and after Revascularization

Peripheral arterial disease (PAD) represents a major health issue that significantly impacts patient's survival and quality of life. In addition to limb-related events, patients with PAD have an increased risk of myocardial infarction, stroke, and death. However, compared with coronary and cerebrovascular disease, studies addressing optimal risk reduction modalities including antithrombotic therapies in patients with PAD have been underrepresented in the literature. This publication serves as a narrative review of existing evidence on the effectiveness of antithrombotic therapy in patients with PAD. In patients with chronic stable PAD or post-revascularization, antithrombotic therapies including single or dual antiplatelet agents, anticoagulation, or a combination of these treatments have been shown to reduce cardiovascular and limb events. This narrative review provides a summary of the available literature on the management of patients with PAD, categorized into treatment strategies for chronic, post-endovascular treatment, and post-open surgical revascularization and to discuss the antithrombotic protocol utilized at our institution while providing a rational for our treatment algorithm.

A rare case of left colic branch aneurysm presenting with rupture and intra-abdominal hemorrhage

An aneurysm of the inferior mesenteric artery is a rarely described clinical presentation. We have presented the case of a ruptured aneurysm originating from a branch of the inferior mesenteric artery that might represent an aneurysm of the left colic artery or the arc of Riolan. Aneurysms of this anatomic location can develop secondary to mesenteric occlusive disease, alterations in mesenteric blood flow from previous operations, or connective tissue disease. In the present case, a patient with a ruptured inferior mesenteric artery branch aneurysm had presented with intra-abdominal hemorrhage, which was successfully treated with endovascular embolization.

Clinical application and technical details of cook zenith devices modification to treat urgent and elective complex aortic aneurysms

Purpose

To describe technical details of modifying four different Cook Zenith devices to treat complex aortic aneurysms.

Material

In the first three cases, the modification process involved complete stent graft deployment on a sterile back table. Fenestrations were created using an ophthalmologic cautery and reinforced with a radiopaque snare using a double-armed 4–0 Ethibond locking suture based on measurements obtained on centerline of flow. In each instance, a nitinol wire was withdrawn and redirected through and through the fabric and used as a constraining wire. In the fourth patient, modification involved partial stent graft deployment and creation of additional two fenestrations to accommodate renal arteries. The devices are resheathed and implanted in the standard fashion.

Results

Four patients underwent exclusion of their aneurysms, including thoracoabdominal aneurysms (n = 2), a contained ruptured juxtarenal aneurysm (n = 1), and a ruptured failed previous endovascular repair (n = 1). Fifteen fenestrations were successfully bridged with Atrium iCAST stent grafts. Average graft modification time, operative time, contrast volume, radiation dose, estimated blood loss, and hospital length of stay were 89 min, 155.25 min, 58.8 mL, 2451 mGy, 175 mL, and 4.3 days, respectively. One patient required a secondary intervention to treat a type Ib endoleak. During an average follow-up of 25 months, aneurysm sacs progressively shrank without additional intervention.

Conclusion

Physician-modified fenestrated/branched endografts are a safe alternative to custom made devices, especially in urgent cases and should be part of the armamentarium of any complex aortic program.

Management of a contained ruptured infrarenal abdominal aortic pseudoaneurysm caused by inferior vena cava struts injury: A case report and literature review

Aortic pseudoaneurysms are rare entities caused by infection, trauma, atherosclerotic plaque rupture, or aortic instrumentation. Their natural course remains unknown; however, repair is invariably recommended. We present a case of a 71-year-old man with a history of recurrent deep venous thrombosis and pulmonary embolisms who underwent an inferior vena cava filter placement 8 years prior and was found to have a 3.6-cm contained ruptured infrarenal aortic pseudoaneurysm on imaging performed for abdominal pain. His pseudoaneurysm was excluded using a Gore Excluder Endoprosthesis. We further reviewed literature on the subject to highlight the various surgical approaches to this lethal condition.