Acute limb ischaemia : Treatment, outcome and time trends

Sammanfattning: Acute limb ischaemia (ALI) is a frequent emergency associated with high rates of amputation and death. Traditionally, patients with ALI were treated with open surgical removal of the occlusion or bypass surgery. During the past few decades, new endovascular techniques developed.  No larger studies have investigated the optimal contemporary treatment for patients with ALI. Today, there are no international consensus for recommendations for the treatment of ALI, leaving it open to every surgeon or department to decide the best treatment option. This thesis aimed to study patients with ALI as a means to extend the understanding of this group of patients, as well as to investigate treatment options. Data sources included hospital charts or information was gathered from the Swedish nationwide Vascular Registry (Swedvasc), the Swedish Population Registry for deaths and the Swedish Patient Registry for amputations.Paper I compared the results from thrombolysis with and without continuous heparin infusion in 749 thrombolytic procedures, concluding that both treatment strategies were equally successful in achieving revascularisation, with acceptable complication rates for both strategies. Continuous heparin infusion during intra-arterial thrombolysis offered no advantage. Although the regime with continuous heparin infusion was associated with a higher frequency of bleeding complications (p<0.001), this difference disappeared after adjustment for confounders.Paper II studied long-term outcome after thrombolysis and showed that thrombolytic therapy achieves good medium- and long-term clinical outcome, which reduces the need for open surgical treatment in most patients. More than half of the patients in paper II did not require any surgical reintervention or amputation in their remaining lifetime or during a mean of 6.2 years of follow-up. Long-term outcome differed between the aetiological groups. This information is valuable when deciding on the optimal treatment strategy for patients with ALI.Paper III compared outcomes after open and endovascular revascularisation for the treatment of ALI in 16,229 patients treated in 1994-2014. The large propensity score-matched nationwide cohort study revealed that endovascular treatment of ALI was associated with significantly better short-term survival and amputation-free survival compared with open revascularisation.Paper IV investigated acute aortic occlusion (AAO) and subsequent ALI. This study showed that mortality after AAO is high but has improved in the past 20 years. The proportion of AAO secondary to occluded graft/stent/stentgrafts increases over time as a result of the endovascular shift in treating aortic diseases and the proportion of AAO secondary to native artery thrombosis decreases.Taken together, the main findings of this thesis demonstrate a gradual improvement in survival and that endovascular techniques are becoming more frequently used as a first- line treatment of patients with ALI.