Analysis of IN.PACT DEEP trial on the association between changes in perfusion from pre- to postrevascularization and clinical outcomes in critical limb ischemia.

OBJECTIVES: To quantify changes in ankle and toe pressure from pre- to post-endovascular revascularization for critical limb ischemia (CLI) and examine their association with major adverse limb events (MALE).

BACKGROUND: Despite societal guidelines recommendation of routine hemodynamic surveillance following revascularization, little is known about hemodynamic assessment in CLI.

METHODS: Among the 358 patients with CLI from the international multicenter IN.PACT DEEP trial, ankle and toe pressures measurements were available at both baseline and after intervention in 270 and 44 patients, respectively. The change in ankle and toe pressures in response to endovascular revascularization and its association with 1-year MALE (target limb revascularization, amputation, or death) were examined using Kaplan-Meier curves and multivariable Cox proportional hazard analyses. Corresponding optimal cutoff points were also identified.

RESULTS: The mean increase in ankle and toe pressures following revascularization was 33 and 13 mmHg, respectively. Patients with an improvement of ankle pressure >73 mmHg or toe pressure >1 mmHg had similarly the lowest incidence of MALE (23%), while the highest rate of MALE (50%) was found in those whose toe pressure failed to improve by at least 1 mmHg following intervention. In addition, an increase in ankle pressure >73 mmHg was numerically protective against MALE, and more importantly, an increase in toe pressure of >1 mmHg provided statistically significant protection from MALE (adjusted HR = 0.15, 95% CI: 0.04-0.57, P = 0.005).

CONCLUSIONS: Improvements in toe pressure post revascularization are incremental and rarely normalize. Toe pressure, compared to ankle pressure, is more useful in CLI and predicts future MALE.