Joseph Bonn

Results of a multicenter study of the modified hook-titanium Greenfield filter

Initial efforts to modify the stainless steel Greenfield filter for percutaneous insertion led to development of a titanium Greenfield filter, which could be inserted by use of a 12F carrier. This device functioned well as a filter but had an unacceptable 30% rate of migration, tilting, and penetration. Therefore a titanium Greenfield filter with modified hooks was developed and has been tested in 186 patients at 10 institutions. Successful placement occurred in 181 (97%); placement of the remainder was precluded by unfavorable anatomy. A contraindication to anticoagulation was the most frequent indication for insertion (75%). All but two were inserted percutaneously, predominantly via the right femoral vein (70%). Initial incomplete opening was seen in four patients (2%), which was corrected by guide wire manipulation and asymmetry of the legs in 10 (5.4%). Insertion site hematoma occurred in one patient, and apical penetration of the cava during insertion occurred in a second patient. Both events were without sequelae. Follow-up examinations were performed at 30 days at which time 35 deaths had occurred. Recurrent embolism was suspected in six patients (3%) and two of three deaths were confirmed by autopsy. Filter movement greater than 9 mm was seen in 13 patients, (11%) and increase in base diameter greater than or equal to 5 mm was seen in 17 patients (14%). CT scanning showed evidence of caval penetration in only one patient (0.8%). Insertion site venous thrombosis was seen in 4/46 (8.7%) patients screened. The modified hook titanium Greenfield filter is inserted percutaneously or operatively through a sheath, eliminating concern for misplacement from premature discharge.(ABSTRACT TRUNCATED AT 250 WORDS)

Placenta accreta: Comparison of cases managed with and without pelvic artery balloon catheters

OBJECTIVE To describe our experience with the use of prophylactic pelvic artery balloon catheters in cases of placenta accreta diagnosed by antenatal ultrasound and to compare these cases with contemporary controls. METHODS In this prospective study, all patients seen at our institution between January 1994 and August 1997 with the antenatal sonographic diagnosis of placenta accreta were offered prophylactic preoperative pelvic artery balloon catheterization. Patients who were delivered by cesarean hysterectomy for unsuspected placenta accreta in our institution during the same time interval served as controls. Five patients with the sonographic diagnosis of placenta accreta underwent prophylactic pelvic artery balloon catheterization. Surgical outcomes in patients who received balloon catheters were compared with those managed without them. Statistical analysis was performed using the Mann-Whitney U test. RESULTS Five patients with placenta accreta or one of its variants were correctly identified with antenatal ultrasonography. Of the five patients who underwent pelvic artery balloon catheterization, all had placenta accreta and four required cesarean hysterectomy. The mean estimated blood loss, transfusion requirement, and length of hospitalization in patients undergoing hysterectomy managed with and without the balloon catheters was not different (P > 0.06). CONCLUSIONS Antenatal sonographic diagnosis of placenta accreta enables preoperative planning. In our experience, use of pelvic artery balloon occlusion catheters in patients requiring a cesarean hysterectomy for placenta accreta did not improve surgical outcomes compared with patients managed without them. These preliminary findings are based on a small number of patients; therefore, further investigation is needed.

Incidence of Central Vein Stenosis and Occlusion Following Upper Extremity PICC and Port Placement

AbstractThe purpose of this study was to determine the incidence of central vein stenosis and occlusion following upper extremity placement of peripherally inserted central venous catheters (PICCs) and venous ports. One hundred fifty-four patients who underwent venography of the ipsilateral central veins prior to initial and subsequent venous access device insertion were retrospectively identified. All follow-up venograms were interpreted at the time of catheter placement by one interventional radiologist over a 5-year period and compared to the findings on initial venography. For patients with central vein abnormalities, hospital and home infusion service records and radiology reports were reviewed to determine catheter dwell time and potential alternative etiologies of central vein stenosis or occlusion. The effect of catheter caliber and dwell time on development of central vein abnormalities was evaluated. Venography performed prior to initial catheter placement showed that 150 patients had normal central veins. Three patients had central vein stenosis, and one had central vein occlusion. Subsequent venograms (n = 154) at the time of additional venous access device placement demonstrated 8 patients with occlusions and 10 with stenoses. Three of the 18 patients with abnormal follow-up venograms were found to have potential alternative causes of central vein abnormalities. Excluding these 3 patients and the 4 patients with abnormal initial venograms, a 7% incidence of central vein stenosis or occlusion was found in patients with prior indwelling catheters and normal initial venograms. Catheter caliber showed no effect on the subsequent development of central vein abnormalities. Patients who developed new or worsened central vein stenosis or occlusion had significantly (p = 0.03) longer catheter dwell times than patients without central vein abnormalities. New central vein stenosis or occlusion occurred in 7% of patients following upper arm placement of venous access devices. Patients with longer catheter dwell time were more likely to develop central vein abnormalities. In order to preserve vascular access for dialysis fistulae and grafts and adhere to Dialysis Outcomes Quality Initiative guidelines, alternative venous access sites should be considered for patients with chronic renal insufficiency and end-stage renal disease.

Evaluation of a New Percutaneous Stainless Steel Greenfield Filter

PURPOSE To evaluate a new percutaneous Greenfield filter with an alternating hook design and over-the-wire delivery system. MATERIALS AND METHODS The alternating hook stainless steel Greenfield filter was evaluated in a prospective clinical trial between March 10, 1994, and January 27, 1995. Filters were placed in 75 patients in nine clinical centers and follow-up with radiographs and ultrasound scans was carried out at 30 days. RESULTS Clinical trial results revealed successful placement in all patients. There were four cases of filter limb asymmetry (5.3%) without clinical sequelae, with one incidence of failure to span the cava. No significant migration was found. There were no clinically suspected pulmonary emboli, but one instance of probable caval penetration (1.7%) did occur. Caval occlusion was documented in three patients (5%). CONCLUSION The percutaneous stainless steel Greenfield filter provides ease of insertion and improved deployment while maintaining the high standards of efficacy and safety associated with the standard and titanium Greenfield filters.

Labial Necrosis After Uterine Artery Embolization for Leiomyomata

BACKGROUND Uterine artery embolization is increasingly used as an alternative to myomectomy, hysterectomy, and medical treatment for the management of symptomatic leiomyomata. CASE A woman with an 18‐week–size fibroid uterus who underwent uterine artery embolization developed a 3‐cm, exquisitely tender, hypopigmented, necrotic‐appearing area on the right labium minus. Spontaneous resolution occurred over 4 weeks. CONCLUSION Labial necrosis is a possible complication of uterine artery embolization and may be successfully managed with conservative therapy.

Venography with carbon dioxide as a contrast agent

PurposeThe purpose of this study was to evaluate the feasibility, safety, and potential role of carbon dioxide (CO2) as a contrast agent for venography.MethodsConsecutive patients with contraindications to iodinated contrast agents or with unsatisfactory iodinated contrast studies underwent CO2 digital subtraction venography. The images were rated by three experienced angiographers. Image quality and complications were assessed.ResultsOver a 14-month period, 66 vein segments were studied in 21 patients. There was good correlation between experienced angiographers on CO2 image quality (Ri = 0.80) and good agreement on diagnosis (k = 0.62). In 91% of the vein segments evaluated with CO2 there was interobserver agreement on the diagnosis. Upper extremity veins were adequately imaged with CO2 alone in all (6/6) patients with contraindications to iodinated contrast. Following suboptimal iodinated contrast studies in six patients, CO2 produced significantly better quality upper extremity central vein images (p < 0.05). Pain following injection into peripheral veins was the only CO2-related complication. Inferior vena cava (IVC) filters were successfully deployed with CO2 alone in 78% (7/9) of patients; two required iodinated contrast.ConclusionBased upon initial experience, CO2 venography can be recommended in patients with contraindications to iodinated contrast or unsatisfactory iodinated contrast studies.

Complications of a Percutaneous Suture-mediated Closure Device versus Manual Compression for Arteriotomy Closure: A Case-controlled Study

PURPOSE To evaluate the incidence and types of complications encountered with use of a percutaneous suture-mediated closure device versus manual compression for arteriotomy closure in a retrospective case-controlled study. MATERIALS AND METHODS The authors identified 100 consecutive patients, 15 men and 85 women 21-85 years of age (mean, 50 years), between December 2000 and July 2001 in whom the Closer percutaneous suture-mediated closure device was used during 65 uterine artery embolization (UAE) procedures, 11 hepatic chemoembolization procedures, nine diagnostic angiography procedures, seven peripheral vascular interventions, six visceral arterial interventions, and two thrombolysis procedures. An age-, sex-, and procedure-matched control population was identified in which manual compression was performed. Procedure reports and clinical charts were reviewed for the presence of puncture-site complications, as categorized according to Society of Interventional Radiology reporting standards, and for risk factors and comorbid conditions (hypertension, diabetes, stroke, smoking, and coronary artery disease). Follow-up visits and imaging studies were reviewed for patients with complications. RESULTS In the Closer group, there were seven device failures, four minor complications, and three major complications. Minor complications included two groin hematomas and two cases of persistent pain at the arteriotomy site. Three major complications consisted of two cases of external iliac artery dissection, one with distal embolization, and one case of common femoral artery (CFA) occlusion and distal embolization. All major complications occurred in women undergoing UAE. One patient required thromboendarterectomy and patch angioplasty to repair the CFA occlusion, as well as amputation of a gangrenous toe. In the manual-compression group, there was one minor complication (a groin hematoma) and no major complications. There were significantly more complications in the Closer group than in the manual compression group (P =.02). CONCLUSIONS Significantly more complications were associated with use of a percutaneous suture-mediated closure device than with manual compression for arteriotomy-site hemostasis. Major complications and associated morbidity may be seen with use of percutaneous suture-mediated closure devices. In particular, an unexpectedly high frequency of device-related complications was demonstrated in young women undergoing UAE.

Quality Improvement Guidelines for Uterine Artery Embolization for Symptomatic Leiomyomata

Uterine artery embolization (UAE) is assuming an important role in the treatment of women with symptomatic uterine leiomyomata worldwide. The following guidelines, which have been jointly published with the Society of Interventional Radiology in the Journal of Vascular and Interventional Radiology, are intended to ensure the safe practice of UAE by identifying the elements of appropriate patient selection, anticipated outcomes, and recognition of possible complications and their timely address.

Comparison of Conventional Angioplasty with the Palmaz Stent in the Treatment of Abdominal Aortic Stenoses from the STAR Registry

PURPOSE To retrospectively compare the safety and short-term efficacy of conventional percutaneous transluminal angioplasty (PTA) and PTA with the Palmaz balloon-expandable intravascular stent for the treatment of infrarenal abdominal aortic atherosclerotic stenoses. PATIENTS AND METHODS The records of 25 patients with infrarenal aortic stenoses treated by means of percutaneous techniques were retrieved from the SCVIR Transluminal Angioplasty and Revascularization (STAR) Registry and analyzed. Thirteen patients were treated with PTA alone and 12 were treated with the Palmaz intravascular stent. RESULTS Technical success was achieved in 92% of patients treated with PTA alone and in 100% of those treated with the Palmaz stent. Significant improvements in lesion morphology, hemodynamics, clinical status, and ankle arm indexes were shown in both groups. There was no statistically significant difference in percent stenosis reduction, decrease in trans-stenotic gradient, or initial clinical outcome between the group treated by means of PTA and the group treated by means of PTA with the Palmaz stent. CONCLUSIONS PTA and intravascular stent placement of atherosclerotic stenoses involving the infrarenal aorta are both safe and efficacious therapeutic modalities. At present, it does not appear that primary stent placement confers any short-term benefits over technically successful PTA in aortic stenoses.

ACCURACY AND SAFETY OF CARBON DIOXIDE INFERIOR VENA CAVOGRAPHY

PURPOSE The purpose of this study was to assess the accuracy of carbon dioxide compared to iodinated contrast material for determining inferior vena cava (IVC) diameter prior to filter placement, and to assess the safety of CO2 when used for this purpose. PATIENTS AND METHODS Consecutive patients undergoing inferior vena cavography prior to filter placement were prospectively evaluated with use of both CO2 and iodinated contrast material. The diameter of the IVC was measured and compared in the same four locations in each patient for both agents. The diameter was corrected for magnification and pin-cushion distortion. The ability of CO2 to correctly classify IVC diameter as < or =28 mm or >28 mm, based on the IVC diameter with iodinated contrast material, was determined. A consensus panel assessed renal vein visualization with CO2 and iodinated contrast material. Blood pressure and arterial oxygen saturation were measured immediately before and after CO2 injection. RESULTS Among 30 patients, there was no significant difference in the measured diameter of the IVC with CO2 versus iodinated contrast material after correction for magnification and pin-cushion distortion. One of 30 patients (3.3%) in this study was misclassified as having an IVC < or =28 mm with CO2 when, in fact, the IVC diameter was >28 mm based on iodinated contrast material. This could be clinically significant for certain IVC filters. Forty-seven percent of renal veins identified on contrast venography were identified by CO2 vena cavography. There was no significant difference in the blood pressure or oxygen saturation values measured before and after CO2 injection. However, one patient with pulmonary artery hypertension did experience transient, symptomatic hypotension after CO2 injection. CONCLUSIONS In most patients, CO2 vena cavography accurately evaluated IVC diameter prior to filter placement. In 3.3% of patients, the discrepancy in measurements between CO2 and iodinated contrast material could be clinically significant, depending on the type of filter placed. CO2 was less accurate than iodinated contrast material in identifying renal veins. Although CO2 vena cavography is safe in the majority of patients, it should be used with caution in patients with pulmonary hypertension.