Significant prostacyclin/thromboxane level imbalance after lower limb arterial angioplasty: a possible platelet function alteration.

PURPOSE: The authors investigated prostacyclin (PGI2) and thromboxane (TX) productions in peripheral venous blood after lower limb revascularization by percutaneous transluminal angioplasty (PTA) versus diagnostic angiography. The purpose of this study was to investigate PGI2/TX imbalance after PTA. This imbalance is of pathophysiologic importance and it is a potential sign of platelet function alteration. MATERIALS AND METHODS: Twenty-five patients requiring PTA were compared with 20 patients undergoing angiography alone from April 2004-December 2005 from a single vascular unit. Patient age range was 42-90 years, and the majority of patients were men. Prostaglandin F2-alpha (PGF2-alpha) and thromboxane B2 (TXB2) were measured sequentially (preprocedure, at 1 hour, and 24 hours after procedure). Differences between postprocedure and preprocedure level were compared statistically between angiography and PTA. RESULTS: Baseline demographics were distributed equally between the two groups except presence of critical ischemia and ankle brachial pressure index, which were two significant confounders. TXB2 was significantly higher after PTA at 1 hour and 24 hours after PTA (P = .005 and P = .014 respectively), PGF2-alpha was significantly higher 24 hours after PTA only (P = .018) (Mann-Whitney U test). CONCLUSIONS: PGI2/TX balance homeostasis is of significant pathophysiologic importance. The authors found that PTA results in significant PGI2/TX imbalance and shifts more toward increased TX production. This finding is partly suggestive of significant platelet activation. This imbalance in PGI2/TX level may have implications for future failure of PTA. Future research in reducing this platelet activation is recommended.

Percutaneous transluminal angioplasty of lower limb arteries causes a systemic inflammatory response.

BACKGROUND: Percutaneous transluminal angioplasty (PTA) of a lower limb arterial segment is a well-established treatment for suitable lesions for critical or noncritical lower limb ischemia. Our aim was to define the inflammatory response after PTA by measuring inflammatory markers. METHODS: Twenty-five patients having PTA were compared with 20 patients having angiography alone. Interleukin-6 (IL-6), IL-8, IL-10, and tumor necrosis factor-alpha (TNF-alpha) were measured sequentially. The difference between postprocedure and preprocedure baseline levels were compared statistically between angiography alone and PTA. Patients were followed up to 1 year after the procedure, and the failure rate of PTA was noted. RESULTS: IL-6 and TNF-alpha were significantly higher in PTA patients at 1 hr after PTA (p < 0.05), and the IL-6 level only was significantly higher at 24 hr post-PTA (p < 0.05) compared to angiography alone (Mann-Whitney test). IL-8 and IL-10 levels did not differ significantly in the PTA group. At 1 year after the procedure, 45% of PTAs had failed. There was no statistically significant correlation between failed PTA and inflammatory response. CONCLUSION: PTA appears to cause a significant inflammatory response compared to angiography alone. This demonstrates a systemic manifestation of localized ischemia/reperfusion injury. Further investigation of the inflammatory response due to ischemia/reperfusion injury and its correlation with restenosis is recommended.

Changes in vascular flow after transdermal oestradiol therapy for prostate cancer: a mechanism for cardiovascular toxicity and benefit?

OBJECTIVE: To report the influence of transdermal oestradiol therapy on the vascular dynamics of men with advanced prostate cancer. PATIENTS AND METHODS: Twenty patients with newly diagnosed locally advanced or metastatic prostate cancer (10 each) were treated using transdermal oestradiol patches. The vascular flow was assessed 6-monthly before and during a year of therapy using arterial and venous Doppler and duplex ultrasonography, arterial and venous photoplethysmography and opto-electronic plethysmography. RESULTS: Arterial flow, as measured by the mean and peak systolic velocities and photoplethysmography, significantly increased over time. Arterial compliance initially decreased but had normalized after 12 months. The venous variables were unaffected. As a result, the total limb blood flow and the capillary filtration rate were significantly increased. CONCLUSION: Transdermal oestradiol therapy causes an increase in arterial but not venous flow, and an initial decrease in arterial compliance, which adapts to the physiological range with time. It is possible that these changes may account for the increase in cardiovascular toxicity seen in the early phase of oestrogen therapy, and the cardioprotective effect that accrues thereafter.