Utility of a Steerable Microcatheter in Balloon-assisted Coil Embolization for Inferior Epigastric Artery Injury Following Catheter Ablation: : A Report of Two Cases

Abstract

Inferior epigastric artery injury during femoral vein puncture is rare but typically occurs near its origin, requiring a careful and technically demanding approach. We report two cases of proximal right inferior epigastric artery injury following femoral vein puncture during catheter ablation. To minimize further damage, a steerable microcatheter was used to approach the distal inferior epigastric artery by adjusting its tip direction, and coil embolization was initiated distally. For proximal embolization, a balloon catheter was placed in the right external iliac artery for balloon-assisted, controlled coil packing at the origin. Complete hemostasis was achieved in both cases without complications. Balloon-assisted coil embolization using a steerable microcatheter appears to be an effective technique for managing proximal inferior epigastric artery injuries associated with femoral vein puncture.

Introduction

Vascular access site bleeding is the most common complication associated with catheter ablation for arrhythmias, occurring in approximately 1%-7% of cases, with major bleeding requiring surgical intervention reported in 0.1%-0.3% of cases [1]. Among these, injury to the inferior epigastric artery (IEA) is a notable but underrecognized complication.

Due to the anatomical course of the proximal IEA running anterior to the femoral vein, venous puncture during catheter ablation can lead to proximal IEA injury, often resulting in pseudoaneurysm formation and arteriovenous shunting. This pattern differs from previously reported iatrogenic IEA injuries, which were typically associated with abdominal wall procedures such as paracentesis, drain placement, or laparoscopic surgery, and involved distal branches or peripheral segments of the IEA [2, 3].

Proximal IEA injury requires a careful embolization strategy to achieve complete hemostasis and prevent rebleeding. Therefore, balloon-assisted coil embolization using a steerable microcatheter was used as a safe and effective approach for this purpose (Figure 1). This technique is expected to enable guidewire passage without causing additional damage to the injured segment (Figure 1A) and achieve dense coil packing at the arterial origin (Figure 1B).

Figure 1.

Overview of balloon-assisted coil embolization using a steerable microcatheter for proximal inferior epigastric artery injury.

A) Safe catheter navigation to the distal inferior epigastric artery using a steerable microcatheter. Catheterization of the inferior epigastric artery is facilitated by adjusting the tip orientation of the steerable microcatheter, regardless of whether the branching angle is acute (A-1) or obtuse (A-2). Furthermore, fine control of the steerable microcatheter tip allows the guidewire to be advanced distal to the pseudoaneurysm while avoiding the injured segment.

A-1) Example of tip adjustment for an acute branching angle.

A-2) Example of tip adjustment for an obtuse branching angle.

White arrow: steerable microcatheter, black arrow: micro guidewire, black arrowhead: pseudoaneurysm.

B) Balloon-assisted coil embolization at the proximal inferior epigastric artery using a steerable microcatheter. During proximal coil embolization, adjusting the tip orientation of the steerable microcatheter helps maintain stable positioning. Although coils are designed to fill gaps within the vessel lumen, they may come into contact with the vessel wall or previously deployed coils, potentially causing the microcatheter to kick back or dislodge from the inferior epigastric artery. Additionally, coils may escape into the pseudoaneurysm or extravascular space through the injured site. By aligning the steerable microcatheter tip coaxially with the branching angle of the inferior epigastric artery, these risks can be minimized.

B-1) Example of balloon-assisted embolization in an acute branching angle.

B-2) Example of balloon-assisted embolization in an obtuse branching angle.

White arrow: steerable microcatheter, black arrow: microcoil, black arrowhead: pseudoaneurysm.

In this report, we present two cases of proximal IEA injury following catheter ablation that were successfully treated using this technique. We emphasize the technical considerations and advantages of this approach, which may become increasingly relevant as the number of ablation procedures continues to rise.

Case Reports

This report is a retrospective case series and, therefore, did not require approval from the institutional review board at our institution. Informed consent was obtained from each patient for the procedures and research.

Case 1

A 57-year-old man receiving anticoagulant therapy for arrhythmia underwent catheter ablation for atrial fibrillation. Venous access was obtained by confirming the femoral head position under fluoroscopy, followed by ultrasound-guided puncture of the femoral vein. Three sheaths were inserted in a tandem fashion: two 8.5-Fr sheaths (SL0; Abbott Medical, Abbott Park, IL, USA) and one 7-Fr sheath (Terumo, Tokyo, Japan). After discharge, the patient noticed a subcutaneous hematoma at the puncture site. Duplex ultrasonography performed on postoperative day five revealed an arteriovenous shunt. Contrast-enhanced CT demonstrated a small pseudoaneurysm and arteriovenous fistula at the proximal segment of the right IEA (Figure 2A). The branching angle of the IEA was approximately 135°, and the vascular injury site was located at the mid-level of the femoral head. The patient was hemodynamically stable without anemia. Given that ultrasound-guided compression failed, urgent transcatheter arterial embolization was planned.

Figure 2.

Case 1. A) Three-dimensional volume-rendered image from contrast-enhanced CT. A pseudoaneurysm is present at the proximal right inferior epigastric artery (arrow), accompanied by an arteriovenous shunt. B) Pre-procedure angiography from the right external iliac artery. A pseudoaneurysm is observed at the proximal right inferior epigastric artery (arrow), with poor visualization of the distal segment. C) Fluoroscopic image during balloon-assisted coil embolization. D) Post-procedure angiography from the right external iliac artery. The pseudoaneurysm and arteriovenous shunt have completely resolved.

Under local anesthesia, the left common femoral artery was punctured under ultrasound guidance, and the procedure was initiated without systemic heparinization. An 8-Fr, 45-cm guiding sheath (Destination; Terumo) was advanced to the right external iliac artery. A 5-Fr balloon catheter (balloon diameter: 9 mm; Selecon MP, Terumo) and a 2.4-Fr steerable microcatheter (Swift NINJA; SB KAWASUMI, Tokyo, Japan) were navigated to the distal external iliac artery. Angiography revealed a pseudoaneurysm at the proximal IEA and an arteriovenous fistula (Figure 2B). To avoid further injury, the steerable microcatheter tip angle was adjusted to match the IEA branching angle, and contrast medium was injected through the microcatheter to select the IEA. Subsequently, a 0.016-inch microguidewire (Meister; Asahi Intecc, Aichi, Japan) was advanced to the distal IEA under careful manipulation (Figure 1A).

Embolization was performed from the distal IEA toward its origin using microcoils (Interlock [Boston Scientific, Marlborough, MA, USA; 5 mm × 15 cm]; seven Target XL coils [Stryker, Fremont, CA, USA; 5 mm × 15 cm, 5 mm × 15 cm, 5 mm × 15 cm, 3 mm × 9 cm, 3 mm × 9 cm, 2 mm × 3 cm, and 2 mm × 3 cm]). During coil deployment at the IEA origin, the balloon was inflated in the external iliac artery to prevent microcatheter kickback and coil migration (Figure 2C). At this stage, the microcatheter tip was “locked” coaxially with the IEA axis to ensure accurate coil placement (Figure 1B). Final angiography confirmed the complete disappearance of the pseudoaneurysm and arteriovenous fistula (Figure 2D). Hemostasis at the left femoral puncture site was achieved using Perclose ProGlide (Abbott Vascular, Santa Clara, CA, USA). Total fluoroscopy time was 27 minutes. No procedure-related complications occurred, and the patient was discharged two days after the procedure.

Case 2

A 70-year-old man with a history of cerebral infarction who was receiving anticoagulant and antiplatelet therapy underwent catheter ablation for atrial fibrillation. Venous access was achieved by confirming the femoral head position under fluoroscopy, followed by ultrasound-guided puncture of the femoral vein. Three sheaths were inserted in a tandem fashion: two 8.5-Fr sheaths (SL0; Abbott Medical; AbRoad STOUT, Tokyo, Japan) and one 6-Fr sheath (Terumo). Immediately after returning to the ward, a subcutaneous hematoma was noted at the puncture site. Contrast-enhanced CT revealed a small pseudoaneurysm at the proximal segment of the right IEA and a minor retroperitoneal hematoma (Figure 3A). The IEA branching angle was approximately 65°, and the vascular injury site was located at the upper level of the femoral head. The patient remained hemodynamically stable without anemia. Due to pain during ultrasound-guided compression, emergency transcatheter arterial embolization was performed.

Figure 3.

Case 2. A) Three-dimensional volume-rendered image from contrast-enhanced CT. A pseudoaneurysm is present at the proximal segment of the right inferior epigastric artery (arrow). B) Angiogram obtained through a steerable microcatheter. The steerable microcatheter easily reached the right inferior epigastric artery from the left iliac artery without the use of a guiding sheath or angiographic catheter. C) Intermediate fluoroscopic image during balloon-assisted coil embolization. The balloon was inflated in the external iliac artery to prevent kickback of the steerable microcatheter and coil migration. After this image, an additional microcoil was deployed at the vessel origin while the tip of the steerable microcatheter was “locked” in alignment with the vessel axis. D) Angiogram from the external iliac artery after placement of additional coils following Figure 3C, confirming complete disappearance of the pseudoaneurysm.

The procedure was performed under local anesthesia without systemic heparinization via the left common femoral artery. Angiography confirmed a pseudoaneurysm at the proximal IEA (Figure 3B). Unlike Case 1, a guiding sheath was unavailable; therefore, a 9-Fr, 25-cm sheath (Introducer II H, Terumo) was used to advance a 5-Fr balloon catheter, a 2.4-Fr steerable microcatheter, and a 0.016-inch microguidewire. As in Case 1, balloon-assisted coil embolization was performed from the distal IEA toward its origin using microcoils (three Target XL coils [Stryker; 3 mm × 9 cm, 2 mm × 6 cm, and 2 mm × 6 cm]) (Figure 3B and C). Final angiography confirmed the complete disappearance of the pseudoaneurysm (Figure 3D). Hemostasis at the left femoral puncture site was achieved using Perclose ProGlide (Abbott Vascular). Total fluoroscopy time was 13 minutes. No procedure-related complications occurred, and the patient was discharged five days after the procedure.

Discussion

IEA injuries following femoral vein puncture have been previously reported, often attributed to high puncture sites [4, 5]. These injuries typically involve the mid-segment or branches of the IEA and have been treated with transcatheter embolization using coils or N-butyl cyanoacrylate (NBCA). With the increasing adoption of ultrasound-guided venous access in catheter ablation procedures, the incidence of high puncture sites is expected to decline. Nevertheless, the insertion of multiple large-caliber sheaths in a tandem fashion, combined with systemic anticoagulation, remains a significant risk factor for proximal IEA injury in this clinical setting.

Several reports have documented successful coil embolization for proximal IEA injuries after venipuncture [6, 7], but they lack detailed descriptions of the embolization technique―such as catheter selection, coil deployment strategy, and precautions to prevent coil migration or vessel injury. IEA injuries associated with catheter ablation tend to occur at the proximal segment, where the artery courses anterior to the femoral vein, and are frequently complicated by anticoagulant therapy, making complete embolization up to the arterial origin essential for effective hemostasis.

In this report, balloon-assisted coil embolization using a steerable microcatheter enabled safe and precise catheterization of the IEA and dense coil packing at its origin, demonstrating a safe and reproducible approach for managing such injuries.

This technique offers two major advantages.

First, the steerable microcatheter enables safe and precise access to the injured IEA. When the injury is located at the proximal IEA, conventional 4-5-Fr angiographic catheters with rigid tips may worsen bleeding or vasospasm by contacting the injured site and may hinder guidewire advancement into the distal segment. In contrast, the steerable microcatheter has a flexible tip and allows directional adjustment according to the branching angle, thereby reducing the risk of further injury. Moreover, even in cases with steep branching angles where standard microcatheters are difficult to advance, the steerable microcatheter provides superior maneuverability and support, enabling safe IEA catheterization without an angiographic catheter. Previous reports [8] have also demonstrated the utility of steerable microcatheters for accessing target pelvic vessels without an angiographic catheter, owing to their unique tip control and strong support.

In both cases in this report―particularly Case 2―the guidewire was successfully advanced beyond the pseudoaneurysm without additional injury, despite the absence of both a guiding sheath and an angiographic catheter (Figure 1A).

Second, balloon assistance enhances the stability of the steerable microcatheter and enables dense and secure packing at the IEA origin. During coil embolization at the origin, kickback of the microcatheter and coil migration into the parent vessel can occur due to recoil from the vessel wall or previously placed coils. Balloon assistance can prevent these complications. Furthermore, aligning the steerable microcatheter tip coaxially with the IEA branching angle may help reduce the risk of coil misplacement into the pseudoaneurysm or adjacent venous structures through an arteriovenous fistula, ensuring optimal coil positioning (Figure 1B). Using this approach, precise and compact coil placement at the IEA origin was achieved in both cases, contributing to effective and safe embolization.

In this report, an occlusion balloon catheter was used for balloon assistance; however, angioplasty balloons may also serve as suitable alternatives. One concern with balloon-assisted techniques is the risk of thrombus formation due to temporary flow interruption. Systemic heparinization may exacerbate bleeding from the injury site. Therefore, interventionalists must carefully assess the situation and consider strategies such as minimizing balloon inflation time or administering low-dose heparin (e.g., maintaining an activated clotting time around 250 seconds). In the present cases, balloon inflation time was expected to be less than 10 minutes; thus, the procedure was performed without systemic heparinization.

Although Case 2 was successfully treated using only an introducer sheath, in anatomically challenging situations―such as severe arterial calcification or steep aortic bifurcation angles―a guiding sheath would likely be essential for this technique.

Alternative treatments include ultrasound-guided compression, which is often limited by patient discomfort and reduced efficacy under antiplatelet or anticoagulant therapy. Thrombin injection and NBCA embolization carry a risk of distal embolization. Open surgical repair typically requires general anesthesia and a large incision, as arterial control must be achieved in the presence of hematoma and active bleeding.

Nevertheless, conventional angiographic- or microcatheter-based techniques remain the first-line approach for most IEA injuries. The proposed balloon-assisted technique may be particularly useful in proximal lesions or anatomically challenging cases, where standard methods can be technically demanding or potentially increase the risk of further vessel injury.

In conclusion, balloon-assisted coil embolization using a steerable microcatheter appeared to be effective in achieving hemostasis for proximal IEA injuries following catheter ablation for arrhythmias.

Author Contributions

The author (YK) made substantial contributions to the conception and design of the study, data acquisition and interpretation, drafting and revising the manuscript, and has approved the final version for submission. The author agrees to be accountable for all aspects of the work and ensures that any questions related to the accuracy or integrity of any part of the work are appropriately addressed.

Conflicts of Interest

There are no conflicts of interest.

Informed Consent

Informed consent was obtained from the individual participant included in the study.

Consent for Publication

Consent for publication was obtained for the individual's data included in the study.