The Reintervention Index: A New Outcome Measure for Comparative Effectiveness of Lower Extremity Revascularization

Abstract

Reinterventions after lower extremity revascularization (LER) are common. Current outcome measures assessing durability of revascularization rely on freedom from reintervention but do not account for the frequency of repeated LER. The aim of this study is to compare the reintervention index, defined as the mean number of repeat LER, after open and endovascular revascularization. We hypothesized that endovascular procedures have reduced durability and increased frequency of reinterventions. A retrospective review of the charts of consecutive patients undergoing LER for peripheral artery disease (PAD) in 2013-2014 by multiple specialties in a tertiary care center was performed. Patients were divided into open and endovascular groups based on the first LER procedure performed during the study period. Patient characteristics and outcomes were compared between the 2 groups. Multivariable regression was performed to determine factors associated with reintervention. There were 367 patients (Endo=316, Open=51). A total of 211 patients underwent 497 reinterventions (reintervention rate=57.5%, reintervention index=2.35±2.02 procedures [range 1-11]). Patients in the open group were more likely to be smokers (P=0.018) and to have prior open LER (P=0.003), while patients in the endovascular group were older (P<0.001) and more likely to have cardiovascular comorbidities. On follow-up, there was no difference in overall or ipsilateral reintervention rates or reintervention indices between endovascular and open LER. Major amputation was significantly higher after open LER (19.61% vs. 8.54%, P=0.013) but there was no difference in survival (P=0.448). Multivariable analysis did not show a significant relationship between type of procedure and reintervention. The reintervention index provides a measure to assess the frequency of repeat LER. Patients with PAD, in this study, are afflicted with similar extent of reinterventions after open and endovascular LER.