Friese, J.

Rationale: The role of cardiac natriuretic peptides (NPs) in peripheral arterial disease (PAD) or thromboangiitis obliterans (TA) is unknown. Recent studies in mice suggested that BNP may be produced outside the heart in the ischemic limbs contributing to peripheral angiogenesis. Objective: Determine if synthesis or consumption/degradation of NPs occur in the ischemic legs of patients with PAD or TA. Methods: 32 patients with critical limb ischemia (CLI) or claudication (PAD n=31; TA n=1; 20 males; mean age 72.9 years) underwent diagnostic angiography or revascularization. We determined differences of concentrations of BNP, NT-proBNP, and CNP in the blood of proximal veins and arteries of both legs. Concentrations differences were then compared between the more ischemic target and the contralateral self-control legs. Results: Values are means ± SD. P values <0.05 were considered significant. In the PAD group, in the target extremity, concentration step-ups of NT-proBNP (11±68; p=0.40) and CNP (0.45±6.22; p=0.71) were not significant from the arterial to venous blood. In the contralateral self-control legs, NT-proBNP and CNP concentrations drops were also not significant (-37±160, p=0.7; -0.89±4.09, p=0.23). Venous BNP concentrations were significantly lower than arterial both in the target (-66±153, p<0.001) and self-control legs (-59±107, p<0.001). BNP concentrations drops were greater in the CLI than claudication cases driving the overall significance. In the patient with TA, whose only identifiable PAD risk factor was smoking, arterial concentrations of NPs were generally low (NT-proBNP 81; BNP 46; CNP 8.2), but higher than venous concentrations (80; 41; 6.7). Conclusion: Significantly lower venous BNP concentrations suggest possible BNP consumption/degradation in the ischemic legs. Concentrations of NT-proBNP, that has a longer half-life than BNP, were more stable suggesting no significant local production or conversion to BNP. CNP concentrations were stable. Recognizing the angiogenic properties of NPs and lack of evidence of peripheral production, studies are warranted in humans with PAD to determine the potential angiogenic properties of exogenous NPs supplementation in what could be considered a local NPs deficiency state.

ObjectivesEvaluate the success rate of retrievable inferior vena cava filter (IVC) removal in a tertiary care practice.BackgroundRetrievable IVC filters became readily available in the United States following Food and Drug Administration approval in 2003, and their use has increased dramatically. They represent an attractive option for patients with contraindications to anticoagulation who may only need short‐term protection against pulmonary embolism.MethodsAll patients who had undergone placement of a retrievable IVC filter at Mayo Clinic between 2003 and 2005 were retrospectively reviewed to evaluate our initial experience with retrievable inferior vena cava filters at a large tertiary care center. Results: During a three‐year‐period of time, Mayo Clinic, Rochester, MN placed 892 IVC filters of which 460 were retrievable. Of the 460 retrievable filters placed (249 Günther Tulip®, 207 Recovery®, and 4 OptEase®), retrieval was attempted in 223 (48.5%). Of 223 initial attempts, 196 (87.9%) were initially successful and 27 (12.1%) were unsuccessful. Of the 27 unsuccessful initial retrieval attempts, 23 (85.2%) were because of the presence of significant thrombus within the filter and 4 (14.8%) were because of tilting and strut perforation. Of the 23 filters containing significant thrombus, 9 (39.1%) were later retrieved after a period of anticoagulation and resolution of the thrombus.ConclusionsRetrievable IVC filters can be removed with a high degree of success. Approximately one in ten retrievable IVC filter removal attempts may fail initially, usually because of significant thrombus within the filter. This does not preclude possible removal at a later date. © 2015 Wiley Periodicals, Inc.

Prolonged chylothorax is a rare, life-threatening, pleural effusion that may be encountered in the setting of trauma. Conservative treatment may be successful and is the traditional approach in cases of limited chyle output. Early surgical intervention is required in cases with large refractory chyle output, but may be associated with substantial morbidity and mortality. Percutaneous thoracic duct embolization is an uncommon, minimally invasive, safe and effective treatment alternative. We report a case of successful thoracic duct embolization to treat large-volume chylothorax due to blunt trauma.