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.

OBJECTIVE: Unquestionably, the federal government has created financial incentives for vascular interventionists to perform procedures in their offices rather than in a hospital setting. While office venous ablations have been widely embraced by the vascular community, those involving the arterial system have not. One important reason may be related to the cost of the fluoroscopic equipment. Herein, we report on 32 office-based duplex scan-guided balloon angioplasty cases for failing or nonmaturing arteriovenous (AV) access. PATIENTS AND METHODS: Twenty-five patients (14 males; 11 females; mean age 65.1 +/- 9.11) with chronic renal insufficiency underwent 32 office-based ultrasound scan-guided balloon angioplasties of their autologous AV fistulas. Twenty-seven procedures were performed in fistulas that did not mature while the remaining five were performed in failing AV accesses. The indications for these procedures were severe stenoses (>70%) as measured by color duplex scan and confirmed by peak systolic velocity (PSV) step-up >3. Preoperative duplex scan-derived mean volume flows (VFs) and highest stenotic PSV were recorded and compared with postoperative findings. Access site puncture and cannulation with short sheath, wire, and balloon advancement and inflation were guided by duplex scan only. A comparison of revenue for hospital-based vs office-based procedures was performed. RESULTS: All procedures were successfully completed without fluoroscopy and contrast material. There were no systemic complications. One patient (3%) developed an arm hematoma due to focal vein rupture which was controlled by a hand compression for 20 minutes. An additional patient (3%) had a focal intraluminal dissection not obstructing the flow. Comparison of preoperative mean VF (350 +/- 180 mL/minute) and postoperative mean VF (933 +/- 332 mL/minute) demonstrated a statistically significant increase with P < .0001. Preoperative mean PSV 582 +/- 923 cm/second decreased to postoperative 1 mean PSV 244 +/- 97 cm/second (P < .0001). After deduction of procedure-related expenses ($730/case) from the global fee, the net income from these 32 cases totaled $51,746, making the return 4.32 times higher than that of the hospital setting (potential professional fee for the same cases - $11,983). CONCLUSION: This early experience suggests that office-based endovascular repair of AV access under duplex scan-guidance is feasible and safe. The superficial location of AV access facilitates duplex scan visualization. This proposed approach averts contrast material use and radiation exposure. Finally, it appears to be financially more lucrative than the same hospital-based procedures.

PURPOSE: The placement of central catheters is a common procedure. It is also associated with multiple known complications. One of the potential complications that carry high morbidity and morality is arterial puncture and cannulation. Herein, we describe five case reports of a central line that was inadvertently placed in the subclavian artery and successfully removed using a StarClose device (Abbott Laboratories, Redwood CA). METHODS/RESULTS: A retrospective chart review of a prospectively maintained database was performed. We identified five cases of inadvertent subclavian artery cannulation during central venous catheter placement. All catheters were removed successfully either in the operating room under fluoroscopic guidance or at the bedside with closure of the arteriotomy using the StarClose device. No cases required conversion to an open procedure for repair. No postremoval hematomas, bleeding episodes, myocardial infarctions, arrhythmias, or adverse clinical sequelae were identified. DISCUSSION: Based on our limited experience, we feel that this method can be performed safely and expeditiously not only in the operating room but also at the bedside.