A Stepwise Embolization Strategy for a Bronchial Arterial Aneurysm: Proximal Coil and Distal Glue with the Optional Use of a Microballoon Occlusion System

Analysis of angiographic findings and short-term recurrence factors in patients presenting with hemoptysis

OBJECTIVES

The abnormal anatomical alterations of blood vessels during DSA angiography in patients with hematological disorders were retrospectively examined, and the influencing factors of short-term (≤ 6 months) recurrent hemoptysis were statistically analyzed, and the consistency between admission diagnosis and intraoperative diagnosis was evaluated.

METHODS

The intraoperative angiography data of patients who underwent selective bronchial artery embolization for hemoptysis in our hospital from January 2022 to December 2022 were reviewed. They were divided into the observation group and the control group based on whether there was recurrent hemoptysis. The Logistic regression model and forest map were employed to analyze the factors influencing the recurrence rate.

RESULTS

A total of 104 patients were encompassed in this study (12 cases of tuberculosis, 35 cases of infection, 4 cases of lung cancer, 8 cases of bronchiectasis, 22 cases of arteriovenous fistula, 16 cases of aneurysm, and 7 cases of pulmonary hypertension). The coincidence rate of preoperative and intraoperative diagnoses was 73.1%. Pulmonary arteriovenous fistula and aneurysm were the predominant types of diseases that were misdiagnosed. The short-term recurrence rate was 16.3%, mainly attributed to the reopening of responsible vessels related to embolization, angiography leakage, and leaky embolization of specific types of vessels. The recurrence rate of only patients with arteriovenous fistula and aneurysm accounted for 47% of the total recurrence rate. The right bronchial artery, right internal thoracic artery, right thyroid neck trunk, and age were the independent factors influencing the recurrence of hemoptysis (p < 0.05).

CONCLUSIONS

The main reason for angiographic leakage and embolization leakage in cases of hemoptysis is the lack of understanding of the anatomic variations of the vessels responsible. Careful examination of the specific types and locations of the vessels is the principal approach to reducing secondary operations.

An Alternative Endovascular Technique for Treatment of Pulmonary Arteriovenous Malformation: Microballoon-occluded Transcatheter Embolization Using n-butyl-2-cyanoacrylate

PURPOSE

To investigate the safety and efficacy of microballoon-occluded transcatheter embolization using n-butyl-2-cyanoacrylate (NBCA) in patients with a single pulmonary arteriovenous malformation (PAVM).

METHODS

From November 2017 to November 2020, this retrospective study included 38 previously untreated patients with a single PAVM who underwent microballoon-occluded transcatheter embolization using NBCA. All 38 patients had follow-up that included simple chest radiography and contrast-enhanced chest computed tomography (CT).

RESULTS

A microballoon was successfully placed in a feeding artery of the PAVM to control the delivery of the NBCA cast in all 38 patients, with complete embolization of sacs and the feeding artery achieved in all cases. The mean diameters of the feeding artery, sac, and draining vein were 3.9 ± 0.9 mm, 7.5 ± 2.6 mm, and 4.6 ± 1.3 mm, respectively. A fixed 1:2 NBCA/Lipiodol ratio was used, and the mean amount of embolic mixture per patient was 1.4 mL (range 0.6-2.2 mL). There were no complications related to microballoon adhesion and non-target embolization of the systemic circulation. Follow-up CT in all 38 patients with a mean delay of 34.5 ± 8.8 months (range 20.7-56.5 months) showed no continued perfusion of the PAVM.

CONCLUSION

In our hands, microballoon-occluded n-butyl-2-cyanoacrylate embolization seemed to be safe and appeared to be clinically effective in patients with simple and complex types of single PAVM. Therefore, the present technique has the potential to become a standard treatment for a single PAVM.

A ruptured bronchial artery aneurysm presenting with neurological symptoms: A case report

A 72-year-old man visited the emergency department with chief complaints of dizziness and dysarthria. Initially, a stroke was strongly suspected and brain computed tomography (CT) and neck CT angiography were performed; however, a ruptured bronchial artery aneurysm (BAA) was observed. BAA is a rare disease and usually asymptomatic but can be life-threatening. Patients with a ruptured BAA may present with hypovolemic shock, causing symptoms such as suspected cerebrovascular disease due to decreased cerebral blood flow.

X-ray Microtomography to Assess Determinants of In Vivo N-Butyl Cyanoacrylate Glubran®2 Polymerization: A Rabbit-Model Study

Although introduced decades ago, few cyanoacrylate glues have been approved for endovascular use, despite evidence of their usefulness, notably for complex procedures suchas hemostatic embolization. Indications include massive bleeding requiring emergent hemostasis and prevention of severe bleeding during scheduled surgery to remove a hypervascular tumor. Adding radiopaque Lipiodol Ultra Fluid® (LUF) modulates glue polymerization and allows fluoroscopic guidance, but few comparative in vivo studies have assessed the impact of the resulting change in glue concentration or of other factors such as target-vessel blood flow. In a rabbit model, we used ex vivo X-ray microtomography to assess the results of in vivo renal-artery embolization by various mixtures of N-butyl cyanoacrylate (NBCA), metacryloxysulfolane, and LUF. Overall, penetration to the superficial interlobular arteries was achieved in about two-thirds of cases and into the capillaries in nearly half the cases, while cast fragmentation was seen in slightly more than half the cases. Greater NBCA dilution and the blocked-blood-flow technique were independently associated with greater distality of penetration. Blocked-blood-flow injection was independently associated with absence of fragmentation, capillary penetration, a shorter cast-to-capsule distance, and higher cast attenuation. A larger mixture volume was independently associated with higher indexed cast ratio and deeper penetration. Finally, microtomography is an adapted tool to assess ex vivo distribution of glue cast.

Effects of temperature alteration on viscosity, polymerization, and in-vivo arterial distribution of N-butyl cyanoacrylate-iodized oil mixtures

PURPOSE

Temperature alteration can modify the polymerization of n-butyl cyanoacrylate (NBCA)-iodized oil mixtures during vascular embolization; its effects on viscosity, polymerization time, and intra-arterial distribution of the NBCA-iodized oil mixture were investigated.

MATERIALS AND METHODS

In vitro, the viscosities of NBCA, iodized oil, and NBCA-iodized oil mixtures (ratio, 1:1-8) were measured at 4-60 ºC using a rotational rheometer. The polymerization times (from contact with blood plasma to stasis) were recorded at 0-60 ºC using a high-speed video camera. In vivo, the 1:2 mixture was injected into rabbit renal arteries at 0, 20, and 60 ºC; intra-arterial distribution of the mixture was pathologically evaluated.

RESULTS

The mixtures' viscosities decreased as temperature increased; those at 60 ºC were almost four to five times lower than those at 4 ºC. The polymerization time of NBCA and the 1:1-4 mixtures increased as temperature decreased in the 0-30 ºC range; the degree of time prolongation increased as the percentage of iodized oil decreased. The 0 ºC group demonstrated distributions of the mixture within more peripheral arterial branches than the 20 and 60 ºC groups.

CONCLUSION

Warming reduces the mixture's viscosity; cooling prolongs polymerization. Both can be potential factors to improve the handling of NBCA-iodized oil mixtures for lesions requiring peripheral delivery. Temperature alteration influences the polymerization time, viscosity, and intra-arterial distribution of NBCA-iodized oil mixtures. Warming reduces the viscosity of the mixture, while cooling prolongs polymerization.

Embolization using warmed glue via the triaxial microballoon occlusion system for various vascular disorders

PURPOSE

We aimed to illustrate the benefits of using warmed glue for viscosity reduction via the triaxial microballoon system for the treatment of various vascular disorders.

METHODS

Seven patients who underwent 10 treatment sessions for hemoptysis, type II endoleak, post-pancreatic surgical bleeding, spontaneous retroperitoneal bleeding, or ovarian tumor bleeding were evaluated based on technical and clinical outcomes. In the procedure, the triaxial system, consisting of a 4.5-Fr guiding catheter, a 2.8-Fr microballoon catheter, and a 1.9-Fr no-taper microcatheter, was advanced into the target lesion. Glue (33% n-butyl cyanoacrylate mixed with Lipiodol) warmed to 40°C was injected under balloon occlusion.

RESULTS

The common hepatic, right bronchial, intercostals, internal mammary, costocervical, lateral thoracic, superior thoracic, thoracoacromial, inferior thyroid, iliolumbar, lumbar, internal pudendal arteries, and branch of the inferior mesenteric artery were successfully embolized; 100% technical success and 100% clinical success were obtained after each session.

CONCLUSION

Our modified balloon-occluded glue embolization may lead to better handling with more distal glue penetration capability.

Ectopic origin of bronchial arteries: still a potential pitfall in embolization

PURPOSE

To evaluate the influence of ectopic origin of bronchial arteries (BAs) on bronchial artery embolization (BAE) for hemoptysis.

METHODS

CT and angiography images of 50 consecutive sessions in 39 patients (aged 26-93 years; mean, 70.6 years) who underwent BAE for hemoptysis from April 2010 to December 2019 were reviewed. We defined ectopic BA as a systemic artery originating from other than the T5-T6 vertebral level of the descending aorta with course along the major bronchi. The background of patients, number of BAs, culprit arteries, and treatment outcomes were compared between the cases with and without ectopic BAs.

RESULTS

Seventeen patients (43.6%) demonstrated 19 ectopic BAs, originating from the subclavian artery (n = 7), aortic arch above the T5-T6 level (n = 6), internal mammary artery (n = 3), brachiocephalic trunk (n = 2) or lower descending thoracic aorta (n = 1). Total number of BAs in the cases with ectopic BA was significantly greater than those in cases without ectopic BA (p = 0.0062). Required sessions of embolization were similar in the two groups. No procedure-related significant complications were noted; however, four ectopic BAs caused unexpected filling of contrast media or migration of the embolic material from the orthotopic BA to ectopic BA originating from the arch vessels via tiny communication.

CONCLUSION

Although BAE under the presence of ectopic BA is feasible and safe, detection of BAs with ectopic origin, even of small diameter, is needed to avoid risk of non-target coursing of embolic materials.

Use of a micro-balloon catheter in transcatheter arterial embolization of the renal artery for recurrence of symptoms of autosomal dominant polycystic kidney disease

We report a 63-year-old woman who had recurrent symptoms such as remarkable abdominal distension caused by autosomal dominant polycystic kidney disease in spite of previous bilateral renal arterial embolization with microcoils. Renal arterial embolization with trisacryl gelatin microspheres was performed. The embolic agent was infused while the micro-balloon catheter that was coaxially inserted from a 4-F catheter was inflated without any complications. The size of the polycystic kidneys decreased and the symptoms were satisfactorily relieved.