SIR 2024
Embolization
Kalei Hering, BS
Medical Student
Harvard Medical School
Financial relationships: Full list of relationships is listed on the CME information page.
Patrick Sutphin, MD, PhD (he/him/his)
Assistant Professor
Massachusetts General Hospital
Financial relationships: Full list of relationships is listed on the CME information page.
Sanjeeva P. Kalva, MBBS, MD, RPVI, FSIR, FCIRSE, FACR (he/him/his)
Professor
Massachusetts General Hospital
Financial relationships: Full list of relationships is listed on the CME information page.
Pulmonary arteriovenous malformations (PAVMs) are vascular anomalies that can lead to serious complications from hypoxemia to stroke. Endovascular embolotherapy using microvascular plugs (MVPs) has become a standard treatment for PAVMs. Existing guidelines and evidence for PAVM post-embolization surveillance are limited {1,2}. This study aimed to investigate the extent to which PAVM sac size decreases following embolotherapy with MVPs and its impact on the size of draining veins.
Materials and Methods:
We conducted a retrospective data analysis of 36 confirmed PAVMs who underwent embolotherapy with MVPs between 2012-2022. Post-procedure computed tomography angiography (CTA) was performed an average of 234 days after embolization. Sac size (mm) and draining vein diameter (mm) were measured per existing literature standards by an attending radiologist blinded to the clinical outcomes, and statistical analysis was performed {3}.
Results:
Our results demonstrated a significant reduction in PAVM sac size (92 % ± 5.9% reduction) following embolotherapy with MVPs that achieved technical success. The sac size reduction occurred as early as 42 days following embolization. PAVM sac size consistently decreased in all lung locations at an average follow-up interval of 218 days post-embolization (range: 15, 326). Furthermore, we observed a concomitant reduction in the diameter of draining veins from 3.9 mm ± 2.2 mm to 1.6 mm ± 1.1 mm (63% ± 9.4%), which correlated positively with the reduction in sac size (R = 0.60). Subgroup analysis based on the lung location of each PAVM demonstrated similar reductions in sac size, decreasing an average of 91.7% of the initial sac size.
Conclusion:
This study provides quantitative evidence of the reduction of size of PAVM sac and draining vein post embolotherapy using MVPs. Moreover, our findings suggest that sac size reduction may be observed as early as 42 days following treatment. These results contribute to a better understanding of optimal PAVM surveillance intervals. Further long-term follow-up studies are warranted to quantify the rate of post-treatment sac regression and provide evidence for post-treatment surveillance protocols.