Peripheral artery disease leading to major amputation: trends in revascularisation and mortality over 18 years.
Patients with peripheral artery disease (PAD) are at risk for amputation. The aim of this study was to assess the type of revascularisation prior to and the 30-day mortality rate after major amputation due to PAD.Retrospective analysis of consecutive patients undergoing major amputation for PAD between 01/2000 and 12/2017 at a tertiary referral center. The number and target level of ipsilateral revascularisations prior to amputation were analyzed per patient and over the years. There were three types of revascularisation (open, endovascular and combined treatment) at three levels: aortoiliac, femoropopliteal and infrapopliteal. Univariate and multivariate logistic regression models were used to assess the association of level of amputation and patient characteristics with 30-day mortality.312 patients (65.7% male) with a mean age of 73.3 ± 11 years underwent 338 major amputations: 70 (21%) above/through knee and 268 (79%) below knee. A median of 2 (interquartile range, IQR 1-4) revascularisations were performed prior to amputation, with a slight decrease of 1.4% per year from 2000 to 2017 (incidence rate ratio of 0.986 0.974-0.998; Poisson regression analysis, p=0.021). 16% (53/338) of patients underwent primary amputation without revascularisation; this number remained relatively stable throughout the study period. The proportion of exclusively open treatment before amputation decreased substantially from 35% in 2006 to none in 2016, while exclusively endovascular revascularisations were performed increasingly from 17% in 2002 to 64% in 2016. Amputation occurred after a median of 9.5 months (IQR 0.9-67.6 months) if the first revascularisation was aortoiliac or femoropopliteal and after 2.1 months (IQR 0.5-13.8 months) if the first intervention was infrapopliteal (p<0.001) with no significant change over the years (normal linear regression, p=0.887). Thirty-day mortality was 8.9% (22/247) after below knee and 27.7% (18/65) after above/through knee amputation (adjusted OR 3.84, 95% CI 1.74-8.54, p=0.001) with a slight increase of mortality over the study period (adjusted OR 1.09, 95% CI 1.018-1.159, Poisson regression analysis, p= 0.021). The uni- and multivariate analysis of patient characteristics did not show an association with mortality, except higher ASA classification (adjusted OR 2.65, 95% CI 1.23-5.72, p= 0.012).Mortality, especially after above/through knee amputation, remains high over the past two decades. There is a clear shift towards endovascular treatment of patients with PAD prior to major amputation. In patients needing infrapopliteal revascularisations, amputation was performed much sooner than in those with aortoiliac or femoropopliteal interventions, with no improvement over the years. Strategies to extend limb salvage in these patients should be the focus of further research.
Authors: Lisa Abry, Salome Weiss, Vladimir Makaloski, Alan G Haynes, Jürg Schmidli, Thomas R Wyss