According to Dr John Jones, clinical and research fellow in the vascular and endovascular surgery department, Massachusetts General Hospital in Boston, patients who have a Type 2 endoleak for more than six months after endovascular abdominal repair (EVAR), should be considered for early reintervention irrespective of a change of aneurysm sac size.
In the study, a total of 164 patients with Type 2 endoleaks were identified and only those with a sac enlargement of more than 5mm were selected for reintervention. At mean follow up (38.2 months), 131 patients had complete and permanent leak resolution, and within six months there were 33 persistent endoleaks. Of the 33, only two of those endoleaks resolved spontaneously. Patients with Type 2 endoleaks had a significantly increased rate of conversion to open surgery compared to all other patients (9.1 vs. 2.3%). Six patients underwent conversion to open repair (two ruptures, three persistent leak with gradual sac enlargement, one rapid sac enlargement).
Patients with persistent leaks had a significantly increased rate of reintervention (48.8 vs. 10.3%). The reasons cited for re-intervention were: persistent endoleaks associated with sac expansion, the procedure being warranted by the surgeon or a rupture that did not require open repair. A total of 21 catheter-based reinterventions were performed on 16 patients: there were 13 trans-arterial embolisations, five trans-lumbar embolisations, two graft revisions/stents and one lumbar artery ligiation. Only nine of the interventions were successful (defined as leak resolution with a sac size that either decreased or remained stable).
At one, three and five years, the freedom from rupture for all patients with persistent endoleaks was 96.7%, 96.7% and 91.4% respectively; freedom from rupture for those who had leak resolution at six months was 98.8%, 96.3% and 96.3%. A total of 27 of the endoleaks were treated with coil embolisation, oversized stent or repeat endograft, but complete resolution was achieved in only 15 of the persistent endoleaks. Additionally, freedom from sac expansion at one, three and five years was 97.5%, 94.5% and 88.1% for no leaks and 88.1%, 51.5% and 32.8% for persistent leaks.
Overall survival was not significantly different between patients with or without a Type 2 endoleak. Smoking history was a significant predictor (56%); however other risk factors, such as coumadin use, congestive heart failure and renal failure were not.
Co-authors of the study, also from Massachusetts General Hospital, reported success in treating about 60% of the patients with persistent endoleaks. They said that evidence from the 45% who had a benign course still favours early intervention, because even patients without sac enlargement can have adverse events, including rupture. Furthermore, the risk of aneurysm sac growth in patients with persistent endoleak does not appear to decrease over time. Spontaneous resolution of such endoleaks is rare, so conservative management of these patients equals a long period of frequent surveillance, they added.
However, the researchers added that with the negative impact of Type 2 endoleaks on patients undergoing EVAR the study showed that to prevent adverse outcomes a more aggressive approach to management of these endoleaks should be strongly considered.