This study is a first step toward US-based wall stress analysis, which would be the modality of choice to monitor wall stress development over time because no ionizing radiation and contrast material are involved.

Replacing duplex US with contrast-enhanced MR angiography for the initial imaging work-up of patients with PAD reduces the need for additional imaging, although diagnostic costs are higher.

Background and Purpose-Chlamydia pneumoniae has repeatedly been associated with atherosclerotic disease. Our study was designed to clarify whether this association is based on C pneumoniae-induced transformation of a stable into an unstable atherosclerotic plaque or on stimulation of hypercoagulability leading to increased thrombotic arterial occlusions by C pneumoniae infection. Transcranial Doppler ultrasonographic monitoring of the middle cerebral artery during carotid endarterectomy offers the opportunity to study, before removal of the plaque, atherothrombotic emboli dislodging from an unstable carotid plaque (plaque-related emboli) and emboli related to (excessive) thrombus formation at the endarterectomy site after removal of the plaque and restoration of flow (thrombosis-related emboli). Methods-C pneumoniae IgA (Ն1/16) and IgG (Ն1/64) seropositivity was assessed in 53 patients with symptomatic carotid artery disease undergoing carotid endarterectomy. The removed carotid plaques were studied histologically to assess plaque instability. Results-Plaque-and thrombosis-related emboli were registered in 43 patients with an adequate transtemporal window.IgA seropositivity (58%) was associated significantly with thrombosis-related embolization (Pϭ0.030) but not with plaque-related embolization or with histological plaque instability. Conclusions-C pneumoniae serology is associated with microembolization after endarterectomy and restoration of flow.Since these microemboli represent platelet aggregations and are related to cerebrovascular complications, our data suggest that C pneumoniae infection contributes to cerebrovascular events in patients with carotid artery disease through stimulation of thrombosis.

ObjectivesThe aim of this work was to develop a MRI method to determine arterial flow reserve in patients with intermittent claudication and to investigate whether this method can discriminate between patients and healthy control subjects.MethodsTen consecutive patients with intermittent claudication and 10 healthy control subjects were included. All subjects underwent vector cardiography triggered quantitative 2D cine MR phase-contrast imaging to obtain flow waveforms of the popliteal artery at rest and during reactive hyperemia. Resting flow, maximum hyperemic flow and absolute flow reserve were determined and compared between the two groups by two independent MRI readers. Also, interreader reproducibility of flow measures was reported.ResultsResting flow was lower in patients compared to controls (4.9±1.6 and 11.1±3.2 mL/s in patients and controls, respectively (p<0.01)). Maximum hyperemic flow was 7.3±2.9 and 16.4±3.2 mL/s (p<0.01) and the absolute flow reserve was 2.4±1.6 and 5.3±1.3 mL/s (p<0.01), respectively in patients and controls. The interreader coefficient of variation was below 10% for all measures in both patients and controls.ConclusionsQuantitative 2D MR cine phase-contrast imaging is a promising method to determine flow reserve measures in patients with peripheral arterial disease and can be helpful to discriminate patients with intermittent claudication from healthy controls.

A short-term course of azithromycin offers no benefits for survival or ankle pressure in PAD-patients.