Prediction of Development of Critical Limb Ischemia in Hemodialysis Patients

Association of Asymptomatic Low Ankle-Brachial Index with Long-Term Clinical Outcomes in Patients after Acute Myocardial Infarction

AIMS

Peripheral arterial disease (PAD) is the well-known risk factor for cardiovascular events. Although low ankle-brachial index (ABI) is recognized as a risk factor in general population, low ABI without any symptoms of PAD has not been established as a prognostic marker in patients with acute myocardial infarction (AMI) yet. The purpose of this retrospective study was to examine whether asymptomatic low ABI was associated with long-term clinical outcomes in AMI patients without treatment history of PAD.

METHODS

We included 850 AMI patients without a history of PAD and divided them into the preserved ABI (ABI ≥ 0.9) group (n=760) and the reduced ABI (ABI ＜0.9) group (n=90) on the basis of the ABI measurement during the hospitalization. The primary endpoint was the major adverse cardiovascular events (MACE) defined as the composite of all-cause death, non-fatal myocardial infarction, and hospitalization for heart failure.

RESULTS

During the median follow-up duration of 497 days (Q1: 219 days to Q3: 929 days), a total of 152 MACE were observed. The Kaplan-Meier curves showed that MACE were more frequently observed in the reduced ABI group than in the preserved ABI group (p＜0.001). The multivariate COX hazard analysis revealed that reduced ABI was significantly associated with MACE (hazard ratio 2.046, 95% confidence interval 1.344-3.144, p=0.001) after controlling confounding factors.

CONCLUSIONS

Reduced ABI was significantly associated with long-term adverse events in AMI patients without a history of PAD. Our results suggest the usefulness of ABI as a prognostic marker in AMI patients irrespective of symptomatic PAD.

Poor survival of dialysis patients with unhealed wounds because of critical limb ischemia: Limb salvage and survival requires wound healing

Maintenance of blood flow in the wound area is required to heal wounds of critical limb ischemia (CLI) in dialysis patients. However, many dialysis patients have both a stenotic lesion in below-knee blood vessels and a cardiovascular event as complications, and thus, it may be difficult to ensure sufficient blood flow. Therefore, many deaths occur because of problems with wound healing. The aim of this study is to identify the optimal treatment, including revascularisation and amputation, from the perspective of wound healing by analysing the survival of hemodialysis patients with CLI who had healed or unhealed wounds in a lower extremity. The subjects were 52 patients who received maintenance dialysis at our clinic, including 27 with healed CLI wounds and 25 with unhealed CLI wounds. The Kaplan-Meier method was used to compare survival between the two groups. Multivariate analysis was conducted to examine the effect of an unhealed wound on mortality. The mean follow-up period was 1.7 ± 1.1 years. In the unhealed wound group, the 1-, 2-, and 3-year survival rates were 48%, 20%, and 12%, respectively. The overall survival rate was significantly lower in the unhealed wound group compared with the healed wound group (12% vs 63%, P = .0002 by log-rank test). In multivariate analysis, unhealed CLI wounds had a significant independent association with mortality (hazard ratio 3.32; 95% confidence interval [CI]: 1.41-8.77, P = .0054). In this study, the 3-year survival rate suggested a significantly poorer prognosis of hemodialysis patients with unhealed CLI wounds compared with those with healed wounds. An unhealed wound is an independent risk factor for mortality in hemodialysis patients with CLI.