Barry T. Katzen

Delayed aortic aneurysm enlargement due to endotension after endovascular abdominal aortic aneurysm repair

Abdominal aortic aneurysm (AAA) enlarges after successful endovascular repair, because of persistent blood flow within the aneurysm sac, or endoleak. In the absence of detectable endoleak, AAA may still expand, in part because of persistent pressurization within the excluded aneurysm, or endotension. We report three patients who underwent successful endovascular AAA repair in whom postoperative surveillance showed aneurysm regression, yet delayed AAA enlargement without demonstrable endoleak developed in all three patients. Endotension was confirmed in all three patients at elective open conversion. Our study underscores the significance of endotension as a mechanism of delayed aneurysm enlargement after successful endovascular AAA repair.

Risk Stratification and Outcomes of Transluminal Endografting for Abdominal Aortic Aneurysm: 7-Year Experience and Long-term Follow-up

PURPOSE To determine early and late outcomes of transluminal endografting (TE) in patients with abdominal aortic aneurysm (AAA), stratified by predicted risk of procedure-related mortality with conventional operation. MATERIALS AND METHODS A retrospective study was conducted in consecutive risk-stratified AAA patients undergoing TE at a not-for-profit cardiovascular referral center from March 1994 through November 2000 with follow-up through February 2001. With use of conventional risk strata (0 = low, 1 = minimal, 2 = moderate, and 3 = high), predicted procedure-related mortalities were 0%-1% in stratum 0 (n = 40), 1%-3% in stratum 1 (n = 118), 3%-8% in stratum 2 (n = 116), and 8%-30% in stratum 3 (n = 31). Main outcome measures were: (i) TE procedural success, (ii) procedure-related mortality, (iii) major nonfatal complications, (iv) composite adverse outcome (ii + iii), (v) length of stay (LOS), (vi) freedom from AAA rupture, (vii) late survival, (viii) late complications, and (ix) endoleaks and their classification and management. RESULTS Women were significantly less likely than men to qualify for and undergo endografting: 24 of 91 (26.4%) women underwent TE, compared to 281 of 684 (41.1%) men. Of 305 attempted TE procedures, 291 (95.4%) were successful, four (1.3%) were urgently converted to open repair, and 10 (3.3%) were aborted. Procedure-related mortalities occurred in eight cases (2.6%) overall and one of 40 (2.5%), one of 118 (0.8%), four of 116 (3.4%), and two of 31 (6.5%) cases for risk strata 0-3, respectively. Perioperative survivors were significantly younger than nonsurvivors (74.3 y +/- 9 vs 81.6 y +/- 5.1; P =.0087). Forty-six patients (15.1%) had major complications. Composite adverse outcome was worse for patients in stratum 3 than those in stratum 1 (P =.0296) and those in strata 0, 1, and 2 combined (P =.026). Procedure-related mortality declined with institutional experience, from 4% among the first 100 patients undergoing TE to 1% among the last 105. For strata 0-3, median LOS were 2, 3, 3, and 4 days, respectively. Seventy patients (22.9%) had 75 endoleaks, of which 30 necessitated additional procedures, 17 self-resolved, and 22 were untreated as of March 1, 2001. Five patients with endoleak died of unrelated causes. One late-onset type IA endoleak (26 mo) resulted in the only AAA rupture and death in the follow-up period among the 291 patients who underwent successful transluminal endograft implantation. Actuarial survival rates at 1 year after TE were 90.3% +/- 1.9% for the overall study group and 97.5% +/- 2.5%, 94% +/- 2.5%, 86.9% +/- 3.3%, and 81.3% +/- 7.7% for risk strata 0-3, respectively. At 5 years, overall actuarial survival was 69.6% +/- 6.1%. Thirty-eight late deaths were attributable to post-TE AAA rupture (n = 1), AAA rupture late after failed TE with no further treatment (n = 1), other cardiovascular disorders (n = 7), cancer (n = 15), other causes (n = 10), and unknown causes (n = 4). Late deaths occurred in risk strata 0-3 at the following rates: two of 40 (5%), 10 of 118 (8.5%), 16 of 116 (13.8%), and 10 of 31 (32.3%), respectively (stratum 0 vs stratum 3, P =.0017; stratum 1 vs stratum 3, P =.003). CONCLUSIONS TE is safe and confers durable protection against AAA rupture in treated populations. Still, protection is not absolute in patients with endoleaks, because late AAA enlargement and even rupture can occur. Given current knowledge, technology, and practice, careful patient selection and close surveillance of patients after implantation of transluminal endografts is essential.

The Influence of Female Gender on the Outcome of Endovascular Abdominal Aortic Aneurysm Repair

PURPOSE Women appear to have a greater risk of death than men after open surgery for abdominal aortic aneurysm (AAA). The aim of this study is to compare outcomes after endovascular AAA repair in men and women. MATERIALS AND METHODS From March 1994 to November 2000, 305 patients (281 men and 24 women) underwent AAA repair with use of endovascular techniques. Outcomes measured included perioperative mortality, percentage of procedures aborted or converted to open abdominal AAA repair, deployment success rate, angiographic success rate, major complication rate, and percentage of patients with endoleaks. RESULTS Patients of both genders were comparable with respect to mean age (74.4 in men vs 75.9 in women; NS). According to the Society for Vascular Surgery/International Society of Cardiovascular Surgery risk stratification method, men and women were also comparable in age risk score (0.60 vs 0.67; NS), pulmonary risk score (0.50 vs 0.83; NS), and renal risk score (0.28 vs 0.17; NS). However, the cardiac risk score was higher in men (1.31 vs 0.80; P <.05) and maximum AAA diameter was greater in men (57.0 mm vs 52.1 mm; P <.01). Eight perioperative deaths (2.6%) occurred (2.8% of men, 0% of women; NS). Proportionately more procedures were aborted in women than men: four (16.7%) versus six (2.1%; P <.01). Conversion to open repair occurred in four men (1.4%) and no women (NS). Deployment success was achieved in 96.4% of men and 83.3% of women (P <.01). Angiographic success was achieved in 84.1% of men and 80% of women (NS). Of 46 major complications, 42 (14.9%) occurred in 281 men and four (16.7%) occurred in 24 women (NS). Sixty-seven patients had endoleaks: 60 were men (22.1%) and seven were women (35%; NS). CONCLUSIONS There was no difference between men and women with respect to perioperative mortality and major complication rates. These findings indicate that being a woman does not adversely influence the outcome of endovascular AAA repair. However, women had a higher rate of aborted procedures. Precise preoperative evaluation may help reduce this problem in women.

Complications of Endovascular Repair of Abdominal Aortic Aneurysms: A Review

The endovascular procedure for repair of abdominal aortic aneurysms has had an enormous impact on the treatment of this challenging disease. Complications, however, do occur and it is important to have a thorough understanding of the array of complications and appropriate management strategies. In this review of endovascular complications, we describe early and late complications paying particular attention to preventive, treatment and surveillance strategies.

Adequacy of an early arterial phase low-volume contrast protocol in 64-detector computed tomography angiography for aortoiliac aneurysms

PURPOSE This retrospective study was conducted to determine whether a low-volume contrast medium protocol provides sufficient enhancement for 64-detector computed tomography angiography (CTA) in patients with aortoiliac aneurysms. METHODS Evaluated were 45 consecutive patients (6 women; mean age, 72 +/- 6 years) who were referred for aortoiliac computed tomography angiography between October 2005 and January 2007. Group A (22 patients; creatinine clearance, 64.2 +/- 8.1 mL/min) received 50 mL of the contrast agent. Group B (23 patients; creatinine clearance, 89.4 +/- 7.3 mL/min) received 100 mL of the contrast agent. The injection rate was 3.5 mL/s, followed by 30 mL of saline at 3.5 mL/s. Studies were performed on the same 64-detector computed tomography scanner using a real-time bolus-tracking technique. Quantitative analysis was performed by determination of mean vascular attenuation at 10 regions of interest from the suprarenal aorta to the common femoral artery by one reader blinded to type and amount of contrast agent and compared using the Student t test. Image quality according to a 4-point scale was assessed in consensus by two readers blinded to type and amount of contrast medium and compared using the Mann-Whitney test. Multivariable adjustments were performed using ordinal regression analysis. RESULTS Mean total attenuation did not differ significantly between both groups (196.5 +/- 33.0 Hounsfield unit [HU] in group A and 203.1 +/- 44.2 HU in group B; P = .57 by univariate and P > .05 by multivariable analysis). Accordingly, attenuation at each region of interest was not significantly different (P > .35). Image quality was excellent or good in all patients. No significant differences in visual assessment were found comparing both contrast medium protocols (P > .05 by univariate and by multivariable analysis). CONCLUSIONS Aortoiliac aneurysm imaging can be performed with substantially reduced amounts of contrast medium using 64-detector computed tomography angiography technology.

The Vascular Center

The 1990s have ushered in new technologies for the treatment of vascular disease at an unsurpassed pace. At the same time, in the United States, changes in the regulatory and economic aspects of medical practice have created unprecedented competitive pressures in the field of vascular care. In other environments, other factors such as ego and political “turf” have contributed to underlying competitive pressures. These pressures have added fuel to an ever-smoldering turf struggle between specialists interested in this field, most notably vascular surgeons, interventional radiologists, and cardiologists, although a few vascular medicine specialists have also participated in conflict. Recently, a considerable amount of rhetoric and commentary regarding perceived roles, responsibilities, and privileges of the various disciplines has been expressed in journals and at meetings of professional societies and postgraduate courses. In hospitals heated credentialing battles have occurred. Pressures to create change

Popliteal Artery Aneurysm Thrombolysis and Subsequent Treatment

A popliteal artery aneurysm (PAA) is generally defined as a focal dilatation of the popliteal artery greater than 50 % of the vessel’s normal diameter and/or a diameter greater than 12 mm. PAA accounts for roughly 80 % of all peripheral aneurysms with a predilection for males. Treatment decision is based on the diameter and the clinical presentation of the PAA. Current practice favors treatment of asymptomatic PAAs with a diameter greater than 20 mm and all symptomatic PAAs. Symptomatic patients may present with lower extremity ischemia ranging from claudication to acute rest pain associated with PAA thrombosis and/or distal embolization. In general, there are two treatment options in patients with symptomatic PAA: endovascular repair and surgical repair, both with or without adjunctive thrombolysis. The high incidence of limb loss associated with an untreated acutely thrombosed PAA (up to 60 %) signals the importance of emergent treatment in these patients. The following case illustrates the steps necessary to diagnose and treat a patient presenting with limb ischemia due to an acutely thrombosed PAA.

Considerations in Evaluating Results of Endovascular Treatment

Self-assessment and quality improvement have always been important in medicine, but they are particularly pertinent in the field of endovascular therapy for the following reasons: