Arterial Calcification Increases in Distal Arteries in Patients with Peripheral Arterial Disease

Abstract

Objective-The aim of this study was to determine if significant differences in plaque composition exist between the popliteal and tibial vessels in patients with severe peripheral arterial disease (PAD).Methods-Forty-four patients with PAD required either above knee (n=38), below knee (n=5) or through knee (n=1) amputation for pedal sepsis/gangrene. The fifty-one vessels (anterior tibial, n=9; posterior tibial, n=10; peroneal, n=3; popliteal, n=29) were obtained, and underwent intravascular ultrasound (IVUS) evaluation ex vivo within 24 hours of amputation. Sequential IVUS data were obtained at known intervals throughout the vessel length, and then analyzed with radiofrequency techniques for quantification of plaque composition, plaque volume, and total vessel volume. Plaque composition was categorized as fibrous, fibro-fatty, necrotic core, and dense calcium. Clinical data was obtained via review of electronic records at the time of amputation. Two-sided t-tests were performed to compare components within each plaque. Results are expressed as mean percentage ±SEM.Results-Tibial vessels had more dense calcium within these plaques than popliteal arteries (33.8 ±5.6% v. 10.6±1.9%, P<0.001).Consequently, distal vessels had less fibro-fatty and fibrous plaque than popliteal arteries (7.7±1.4% v. 13.1±1.2%, P<0.005; 42.4±4.7% v. 61.4±2.2%, P<0.001), respectively. Necrotic core plaque composition was found to be similar when comparing tibial verses popliteal arteries (16.1% vs. 14.9%, p = NS). Clinical factors including diabetes, hyperlipidemia and chronic renal insufficiency were not associated with plaque composition differences using a univariate analysis.Conclusions-As we progress distally in the arterial tree of patients with PAD, calcium plaque content increases with decreasing burden of fibro-fatty plaque. Clinical and demographic factors with the exception of smoking were not found to be associated with atherosclerotic plaque composition.

Correlation Between Arterial FDG Uptake and Biomarkers in Peripheral Artery Disease

“…Additionally, the significant difference in TBR between the peripheral and carotid arteries seen in this study as well as in previous studies (6,7,13) suggests that the degree of inflammation in symptomatic peripheral atherosclerosis is lower than in carotid atherosclerosis. This finding may be due to differences in their pathogenesis: femoral lesions are more likely to be composed of fibrous and calcified material, which accumulates less FDG than lipid-rich, inflamed plaque (17,18). Calcification in the peripheral and carotid arteries was in fact a common finding on the CT images in this study, and previous studies do reveal that inflammation and calcification rarely coexist in the same plaque (5,9).…”

Cost-effectiveness analysis of orbital atherectomy plus balloon angioplasty vs balloon angioplasty alone in subjects with calcified femoropopliteal lesions

“…Remarkably, atherectomy devices as well as stenting are indicated (class IIb) as “salvage” devices to be used in the event of suboptimal BA results 3. The presence of calcified plaque in femoropopliteal lesions is common, and arterial wall calcium is associated with higher rates of procedural complications, including flow-limiting dissections which frequently require stent deployment to maintain vessel patency 5,6. Further, stenting as salvage therapy in calcified segments after failed BA often results in stent underexpansion and malapposition, which increase the probability of subsequent stent fracture and/or restenosis 7,8.…”

Invasive evaluation of plaque morphology of symptomatic superficial femoral artery stenoses using combined near-infrared spectroscopy and intravascular ultrasound

“…20 Compared to PAD patients with popliteal disease, VH-IVUS showed that patients with tibial disease had less fibrous and fibrofatty plaque, more calcified plaque, and similar LCP. 21 The present study is the first to use NIRS-IVUS to characterize the composition of atherosclerotic plaque in patients with symptomatic PAD. Although the observed prevalence of fibrocalcific plaque (97.8%) is much higher than prior autopsy and MRI studies, the differences are probably due to the presence of severe PAD in all of our patients.…”