ABSTRACT
PURPOSE: To evaluate the association between a chronic total occlusion (CTO) and long-term outcomes among patients undergoing endovascular intervention to the external iliac artery (EIA). METHODS: A 2-center retrospective study was conducted of 331 patients (mean age 64.7±12.7 years; 221 men) who underwent endovascular intervention for 481 EIA atherosclerotic lesions between 2006 and 2016. A quarter of the lesions (115, 23.9%) were CTOs. The majority of patients (184, 60.9%) were treated for claudication; 172 (38%) lesions were TransAtlantic Inter-Society Consensus type C or D. Target lesion revascularization (TLR) and major adverse limb event (MALE) rates were compared between lesions with or without an EIA CTO. A Cox proportional hazard model was subsequently developed to determine baseline variables associated with long-term outcomes after successful endovascular intervention of stented EIAs; outcomes are presented as the hazard ratio (HR) and 95% confidence interval (CI). RESULTS: The mean lesion length was longer (84 vs 50 mm, p<0.001) among patients treated for CTOs. While overall the target lesion failure rates were very low (2.8%), vessel perforation (2.7% vs 0.3%, p=0.02) and distal embolization (2.7% vs 0.9%, p=0.02) were more common in the CTO group. Among 377 successfully crossed and stented lesions (93 CTOs), the overall 1-year primary patency was 78% and secondary patency was 92%. One-year and 5-year TLR rates were 8.2% and 15.4%, respectively. CTO intervention was associated with higher 5-year TLR rates in the unadjusted analysis (HR 1.72, 95% CI 1.00 to 2.56, p=0.050), but the association did not remain significant after multivariable adjustment. CONCLUSION: Intervention to EIA CTOs is associated with increased intraprocedural complexity but with similar midterm outcomes, including high patency and low rates of TLR to 5 years.
Subject(s)
Endovascular Procedures , Iliac Artery , Peripheral Arterial Disease/therapy , Aged , California , Colorado , Constriction, Pathologic , Endovascular Procedures/adverse effects , Female , Humans , Iliac Artery/diagnostic imaging , Iliac Artery/physiopathology , Male , Middle Aged , Peripheral Arterial Disease/diagnostic imaging , Peripheral Arterial Disease/physiopathology , Retrospective Studies , Risk Factors , Time Factors , Treatment Outcome , Vascular PatencyABSTRACT
Peripheral artery disease (PAD) is the atherosclerosis of lower extremity arteries and is also associated with atherothrombosis of other vascular beds, including the cardiovascular and cerebrovascular systems. The presence of diabetes mellitus greatly increases the risk of PAD, as well as accelerates its course, making these patients more susceptible to ischemic events and impaired functional status compared to patients without diabetes. To minimize these cardiovascular risks it is critical to understand the pathophysiology of atherosclerosis in diabetic patients. This, in turn, can offer insights into the therapeutic avenues available for these patients. This article provides an overview of the epidemiology of PAD in diabetic patients, followed by an analysis of the mechanisms by which altered metabolism in diabetes promotes atherosclerosis and plaque instability. Outcomes of PAD in diabetic patients are also discussed, with a focus on diabetic ulcers and critical limb ischemia.
ABSTRACT
When a marine mammal dives, breathing and locomotion are mechanically uncoupled, and its locomotor muscle must power swimming when oxygen is limited. The morphology of that muscle provides insight into both its oxygen storage capacity and its rate of oxygen consumption. This study investigated the m. longissimus dorsi, an epaxial swimming muscle, in the long duration, deep-diving pygmy sperm whale (Kogia breviceps) and the short duration, shallow-diving Atlantic bottlenose dolphin (Tursiops truncatus). Muscle myoglobin content, fiber type profile (based upon myosin ATPase and succinate dehydrogenase assays), and fiber size were measured for five adult specimens of each species. In addition, a photometric analysis of sections stained for succinate dehydrogenase was used to create an index of mitochondrial density. The m. longissimus dorsi of K. breviceps displayed significantly a) higher myoglobin content, b) larger proportion of Type I (slow oxidative) fibers by area, c) larger mean fiber diameters, and d) lower indices of mitochondrial density than that of T. truncatus. Thus, this primary swimming muscle of K. breviceps has greater oxygen storage capacity, reduced ATP demand, and likely a reduced rate of oxygen consumption relative to that of T. truncatus. The locomotor muscle of K. breviceps appears able to ration its high onboard oxygen stores, a feature that may allow this species to conduct relatively long duration, deep dives aerobically.
