Abstract
Background and Aims
Although lower extremities bypass surgery has been commonly performed as the standard option to treat peripheral artery disease with critical limb ischemia (CLI) even in patients on haemodialysis (HD) as well as general population, higher amputation and/or mortality rates still remains major clinical problems after bypass surgery in this population. In this 10-year follow-up study, we investigated the impact of HD on outcomes after surgical revascularization in patients with CLI.
Method
A total of 464 patients undergoing successfully elective bypass surgery were enrolled. We compared 304 HD patients with 335 limbs and 160 non-HD (NHD) patients with 183 limbs during 10 years follow-up period. Primary outcome was amputation-free survival (AFS) rate defined as freedom rate from composited endpoint with major amputation (limb amputation above ankle level) or all-cause mortality. To minimize the differences of clinical characteristics between the two groups, propensity score-matching with all baseline variables was performed.
Results
Prevalence of diabetes (55.6% vs. 33.8%), ulcer/gangrene (99.1% vs. 63.5%) and infra-popliteal artery disease (58.9% vs. 32.5%) were significantly higher in HD group compared to NHD group (p<0.0001 in all). Pre-procedural C-reactive protein (CRP) levels was also higher in HD group [14.0 (4.0-51.5) mg/l vs. 7.0 (2.0-34.0) mg/l, p=0.0015]. Inversely, age was younger in HD group than in NHD group (67±9 years vs. 72±8 years, p<0.0001). The 30-day mortality rate was comparable (3.3% in HD group vs. 1.3% in NHD group, p=0.16). During follow-up period (median of 48 months), 53 amputation (17.4%) and 102 death (33.6%) in HD group, and 17 amputation (10.6%) and 23 death (14.4%) in NHD group occurred, respectively. The 10-year AFS rate was significantly lower in HD group compared to NHD group [41.3% vs. 71.3%, hazard ratio (HR) 2.33, 95% confidence interval (CI) 1.64-3.41, p<0.0001). Similarly, limb salvage rate and survival rate was also lower in HD group than in NHD group (72.1% vs. 87.5%, HR 1.90, 95%CI 1.12-3.39, p=0.016, and 51.8% vs. 80.4%, HR 2.78, 95%CI 1.80-4.48, p<0.0001, respectively). In the propensity score-matched cohort, having no significant differences of all baseline characteristics between HD and NHD group (n=125 in each), the 10-year AFS rate and survival rate was still lower in HD group compared to NHD group (53.1% vs. 72.8%, HR 2.11, 95% CI 1.34-3.39, p=0.0012 and 58.6% vs. 84.9%, HR 3.72, 95% CI 2.09-7.06, p<0.0001, respectively). However, the limb salvage rate was statistically comparable between the two group (81.9% vs. 84.2%, HR 1.13, 95%CI 0.55-2.38, p=0.74). In addition, pre-procedural CRP levels could predict major amputation in HD patients (HR 1.06, 95%CI 1.01-1.10, p=0.024) but not NHD patients (HR 1.09, 95%CI 0.93-1.25, p=0.27).
Conclusion
The long-term AFS rate and survival rate were markedly lower in HD patients compared to NHD patients. However, the limb salvage rate was even between HD and NHD after adjustment for clinical characteristics. These results suggest that detection at the early stage of PAD may potentially improve the poor outcome. Pre-procedural inflammation status may also specifically affects the poor outcome in HD group.
Number of infrapopliteal arteries undergoing endovascular treatment is not associated with the limb salvage rate in patients with critical limb ischemia
