NATIONAL HARBOR, MD. – Covered stents may reduce the recurrence of chronic mesenteric ischemia and the need for reintervention in patients undergoing primary interventions, according to Dr. Gustavo S. Oderich.
Freedom from symptom recurrence among primary intervention patients was 92% for those with covered stents, compared with 47% for those with bare metal stents (BMS), he reported at the Vascular Annual Meeting. This difference was significant.
Similarly, freedom from reintervention was 91% at 5 years for the covered-stent group, compared with 54% for the BMS group, also a significant difference.
The findings come from a review of patients who were treated for chronic mesenteric ischemia (CMI) using BMS or covered stents (2000-2010). End points included freedom from symptom recurrence, reintervention, and primary and secondary patency rates.
"Mesenteric angioplasty and stenting [have been] plagued by high rates of restenosis and reinterventions in the range of 30%-60% in different reports," said Dr. Oderich, professor of vascular and endovascular surgery at the Mayo Clinic in Rochester, Minn. Covered stents have been shown to lower restenosis rates when used for renal alignment in fenestrated endografts and for the treatment of failing arteriovenous grafts.
The researchers compared BMS and iCast covered stents (Atrium USA) to determine if covered stents could also reduce restenosis in patients with CMI.
In all, 352 patients were treated for CMI, of which 247 had endovascular revascularization. The researchers included 191 patients in the primary intervention group; of these, 149 (78%) had BMS, 42 patients had covered stents, and 22 patients had angioplasty alone. (The angioplasty-alone patients were excluded from the study.) The primary intervention population included 191 patients; the reintervention population included 36 patients who had undergone open primary intervention.
The two groups were similar in terms of demographics, cardiovascular risk factors, and clinical presentation, but the BMS patients tended to have greater rates of chronic pulmonary disease. The anatomical and procedural variables – including extent of disease, type of approach, number of vessels treated, and stent length and diameter – were also similar, as were early outcomes.
Technical success (defined as successful stent implantation without local complications or stenosis less than 30%) was 95% and 98% for the BMS and covered-stent groups, respectively. Mortality was 3% and 0% for the BMS and covered stent groups, respectively.
The primary patency rate at 5 years was 92% for those with covered stents, compared with 47% for those with BMS, in the primary intervention group. There was no difference in secondary patency rates between the two groups. The average follow-up for the cohort was 29 months.
Multivariate analysis of the primary intervention group showed that the use of a covered stent was a protective factor for loss of primary patency, symptom recurrence, and reintervention.
Other independent predictors of loss of primary patency included age, female sex, and current smoking history. For symptom recurrence, other independent predictors included female sex and current smoking history. For reintervention, age and female sex were independent predictors.
Covered stents also were associated with less recurrence and fewer reinterventions in patients undergoing reintervention for mesenteric chronic ischemia. The reintervention group included 15 patients who were treated with BMS and 21 patients treated with covered stents. The two groups were similar in terms of demographics, cardiovascular risk factors, and clinical presentation. In all, 16 vessels were treated with BMS and 22 with covered stents. The two groups had similar approaches, number of vessels treated, and stent dimensions – with the exception of a slight trend toward longer stents in the covered-stent group.
Dr. Oderich reported that he is the principal investigator of a clinical trial sponsored by Cook Medical.