External Validation and Evaluation of Reliability of the FARP 2 Score to Predict Early Graft Failure after Infrainguinal Bypass.

Background: To evaluate the accuracy of the FARP ₂ (female gender [F], bypass after a previous angioplasty [A], Redo bypass [R], and Pedal bypass [P ₂ ]) scoring system in predicting early graft failure (EGF) after infrainguinal bypass surgery (IBS).
Methods: Charts of patients who underwent IBS between January 2014 and January 2017 in 2 tertiary academic centers were evaluated retrospectively. In follow-ups, 1 week after operation, detailed physical examination was done, Doppler ultrasonography was performed 1 month after operation, and integrity of the graft was evaluated. Calculation of FARP ₂ score was performed by a single surgeon (M.S.) who was well informed regarding FARP ₂ scoring system. The FARP ₂ scoring system was evaluated as following: female gender 1 point, bypass after a previous angioplasty 1 point, redo bypass 1 point, and pedal bypass 2 points.
Results: Totally, 231 patients (180 men and 51 women) were enrolled in the study. The mean FARP ₂ score was 0.52 ± 0.73. The graft occlusion occurred in 23 patients (10%). Presence of critical leg ischemia was lower in patients who faced early graft occlusion (P = 0.002). On the other hand, Rutherford classification score was significantly higher in patients who did not face graft occlusion (4.1 vs. 3.4, P = 0.007). Moreover, unsuccessful angioplasty history and history of previous surgery were more common in that group (P < 0.001 and P < 0.001, respectively). None of the patients faced acute pulse loss, numbness loss, or ulcerative lesion after unsuccessful angioplasty. The mean interval between unsuccessful angioplasty and bypass was 1 ± 1.2 days in our study, which may have a role to prevent undesirable clinical consequences. The FARP ₂ score was 1.5 ± 1.2 and 0.4 ± 0.6 in patients who faced graft occlusion and in patients without occlusion (P < 0.001). Multivariate regression analysis identified that critical leg scheme, presence of unsuccessful angioplasty history, and history of previous bypass operation were found as a predictive factor for EGF (P = 0.044, P < 0.001, and P = 0.003, respectively). Finally, our study demonstrated that patients with FARP ₂ score 3-4 have 2.88-fold increased graft occlusion risk when compared with patients with FARP ₂ score 1-2.
Conclusions: Our study externally validates that the FARP ₂ scoring system is related with EGF after IBS. The FARP ₂ score may be an effective practice in prediction of EGF in patients with peripheral arterial bypass surgery.
(Copyright © 2018 Elsevier Inc. All rights reserved.)