Faculty Bibliography

OBJECTIVE: To evaluate potential predictive factors associated with success or failure of incompetent perforating veins (IPVs) treated with radio-frequency stylet (RFS). METHODS: Over the last 12 months in this observational study, 38 consecutive patients with various degrees of venous insufficiency and IPVs underwent 48 office-based radio-frequency ablation procedures (1 - C 3; 7 - C 4; 10 - C 5; 30 - C 6) in 44 limbs. There were 21 females and 17 males with a mean age of 67 +/- 17 years (38-93 years) who had a total of 93 IPVs (40 calf; 53 ankle). Eighteen patients (47%) had ipsilateral great saphenous vein (GSV) radio-frequency closures performed prior to current procedure. The venous flow pattern was classified by spectral waveform analysis as "normal" (spontaneous with respiratory phasicity) in 33 patients and "pulsatile" (with bidirectional cardiac phasicity) in five patients. Follow-up duplex scans were performed from 3 to 7 days postprocedure. Statistical analyses were performed for determining correlation between the various factors such as, age, pulsatile flow, CEAP class, prior GSV ablation, vein diameter, reflux, and patency. RESULTS: The mean number of ablated IPVs was 1.94 +/- 0.38 ranging from 1-3. Immediate success rate was 88% (82 cases, 32 patients). IPVs had a duplex measured mean diameter of 3.8 +/- 1.1 mm (2-6.6 mm). Eleven IPVs remained patent in six patients. There was no significant difference between the patent and the obliterated IPV groups concerning age (P = 0.75), prior GSV ablation (P = .19), IPV diameter (P = .08) and CEAP classification. Conversely, four of the five procedures (80%) performed in patients with "pulsatile" venous flow failed, while only two of the remaining 43 procedures (4.7%) in patients with "normal" venous flow failed (P < .001). CONCLUSION: These data show that a pulsatile venous flow pattern is a significant predictor of failure following RFS for IPVs.

PURPOSE: While diabetes and homocysteinemia have been demonstrated to be independent risk factors for progression of vascular disease, the activation of telomerase has not been linked to the potent effects of high levels of homocysteine (Hcy) and glucose on vascular smooth muscle cells (VSMC). We examined the proliferative response of VSMCs, resulting from hyperglycemia and hyperhomocysteinemia and their effects on telomerase activity. METHODS: Primary cultures of VSMC from human aorta and arteries were used in this experiment from 3rd -5th passages. Hcy or/and glucose were added to the cell culture media in doses equivalent to plasma levels of Hcy in patients with moderate, high homocysteinemia, or physiologically high concentrations of glucose as seen in diabetics. The modified telomeric repeat amplification protocol was used for telomerase activity assay. Cytotoxicity, viability, proliferation, protein phosphorylation, were determined in cultures treated and not treated with Hcy and glucose. RESULTS: The mitogenic effect of Hcy and glucose on VSMC, independently and together, was observed at 48 hours after treatment. The viable cell numbers were significantly increased at doses comparable to plasma levels of Hcy in hyperhomocysteinemia, as compared to untreated cultures (p < 0.01). Cells exposed to high levels of glucose also exhibited an increased proliferation response (p = 0.01). Telomerase activity was detected in all sets of VSMC cultures exposed to high levels of glucose or/and Hcy (p < 0.01). However, a significant difference was not observed in telomerase activity, when high Hcy or high glucose was used alone or in concert. Significant dual phosphorylation of p38 MAPK was observed in treated cultures but it did not correlate with the telomerase activity detected. CONCLUSION: These data establish a link with telomerase activation and the mitogenic effect of hyperhomocysteinemia and hyperglycemia.

OBJECTIVE: Early limb occlusions following endovascular treatment of aorto-iliac aneurysmal disease is not uncommon (4%-13%). To assess whether the femoral artery entry site could potentially cause this complication, we prospectively evaluated the ipsilateral common femoral artery (CFA) and distal external iliac artery (EIA) with intraoperative duplex scans (IDS). METHODS: There were 134 patients with infrarenal nonruptured abdominal aorto-iliac aneurysms treated with endografts since 2002 at our institution. Age ranged from 65 to 89 years (mean: 77 +/- 7 years). Aneuryx (n = 41), Zenith (n = 50), and Excluder (n = 43) endografts were used for repair. All procedures were performed via open exposure of the CFA. Introducer diameter varied from 12 mm to 22 mm. All patients underwent IDS of the CFA and distal EIA after repair of the arteriotomies. RESULTS: In 34 patients (25%), we documented intimal dissections causing severe (>70%) stenoses. Of the 271 arteries that were examined, 38 (14%) had abnormal findings that demanded intervention. These were repaired with flap excision, tacking sutures revision, or patch angioplasty (n = 36). Repeat IDS confirmed the adequacy of the repair. No statistical difference was noted if the site of larger introducer sheath and the incidence of flap formation. In addition, 10 small flaps or plaques were visualized but did not create significant stenosis. No differences were noted in the incidence of positive duplex exams between each type graft (P = .4). No early or late iliac limb occlusions were noted. Follow-up of 94% was obtained. CONCLUSIONS: Completion arterial duplex scans are helpful in detecting a substantial number of clinically unsuspected technical defects caused by introducer sheaths. Timely diagnosis and repair of these defects may decrease the incidence of early limb occlusion following endograft placement.