Five Year Outcomes of the PRESERVE II Zenith Iliac Branch Pivotal Clinical Study

OBJECTIVE: The PRESERVE II study was an Investigational Device Exemption (IDE) pivotal study performed to evaluate the safety and effectiveness of the Zenith Iliac Branch Graft (ZBIS) with the iCast covered stent system (iCast) in patients with aortoiliac or iliac aneurysms having a morphology suitable for endovascular repair (EVAR).

METHODS: PRESERVE II was a prospective, non-randomized, single-arm, multicenter, clinical study conducted among 18 sites in the United States. Patients were enrolled between 2014-2015, with follow-up to 5 years. The primary endpoint was 6-month freedom from patency-related interventions. Secondary endpoints were 30-day freedom from morbidity and 6-month branch vessel patency.

RESULTS: Forty patients (95% male, mean age 67.8 years) were treated; technical success was 100%. Six-month freedom from patency-related intervention was 100% (39/39), 30-day freedom from morbidity was 85% (34/40), and 6-month branch vessel patency was 100% (37/37). Major complications occurred in 10 patients through follow-up. These included a cardiac event requiring intervention (1), ileus (1), leg ischemia (1), stroke (2), buttock claudication ipsilateral to the ZBIS (1), and impotence (5). Five-year follow-up was available in 75% (30/40) of patients, with complete imaging in 86.7% of available patients (26/30). Freedom from all-cause mortality at 5 years was 88.9%. There was no aneurysm-related mortality. There were 4 occlusions related to the ZBIS through follow-up: 2 in the external iliac artery segment and 2 in the internal iliac artery segment. In total, 4 patients required 6 secondary interventions related to the ZBIS device through 5 years. The treated iliac aneurysm size decreased in 26.9% (7/26) of patients and remained unchanged in 73.1% (19/26) at 5 years. A single case of ipsilateral iliac aneurysm growth was recorded at 4 years post-procedure, associated with a type Ib endoleak. There were no ruptures, type III endoleaks, migrations, or device integrity issues.

CONCLUSIONS: The results of the PRESERVE II study met its performance goals for both primary and secondary endpoints, with higher performance rates than the expected targets. Long-term outcomes support the sustained safety and effectiveness of the ZBIS in combination with the iCast covered stent to preserve hypogastric artery perfusion during EVAR.