Brown, L.C.

Greenhalgh, R.M.

Powell, J.T.

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carotid intimal medial thickness (IMT) and a decrease in left ventricular mass
in patients with type 2 diabetes.
Summary: Target levels of SBP and LDL-C have been recommended
for patients with diabetes. The standard recommendations are target levels
for LDL-C of 100 mg/dL and an SBP of 130 mm/Hg. In this study the
standard target levels were compared withmore aggressive targets of LDL-C
(79 mg/dL) and SBP (115 mm Hg). This was a randomized, open-
label, blinded end point trial. The study period was 3 years (April 2003 to
July 2007), and it was performed at four clinical centers in Oklahoma,
Arizona, and South Dakota. Study participants were 499 American Indian
men and women aged 40 years who had type 2 diabetes but no known
prior cardiovascular events. There were 252 patients randomized to aggres-
sive target levels of LDL-C and SBP and 247 randomized to standard target
levels of LDL-C and SBP. The primary end point was progression of
atherosclerosis as measured by common carotid artery IMT. Secondary end
points were cardiac and carotid ultrasonographic measurements and clinical
events.
In the last 12 months of the study, the mean target (95% confidence
interval) levels were reached in both groups, aggressive vs standard, as
follows: 72 (69-75) and 104 (101-106) mg/dL for LDL-C and 117
(115-118) and 129 (128-130) mm Hg for SBP. Compared with baseline,
IMT regressed in the aggressive group but progressed in the standard group
(0.012 vs 0.038 mm; P  .001). Carotid artery cross-sectional thickness
also regressed in the aggressive group vs the standard group (0.02 mm2 vs
1.05 mm2, P  .001). There was also a greater decrease in left ventricular
mass index in the aggressive group (2.4 g/m2.7 vs1.2 g/m2.7; P .03).
The aggressively treated group had a higher rate of adverse events and
serious adverse events related to blood pressure medications. Clinical car-
diovascular events did not differ significantly between the groups (1.6/100
person-years vs 1.5/100 person-years; P  .87).
Comment: The study poses several dilemmas for clinicians. First, it
only studied a single ethnic group, American Indians. Although the
American Indian population has a high incidence of diabetes and cardio-
vascular events, it is unknown whether the results here can be fully
extrapolated to other ethnic groups. In addition, although there were
improvements in surrogate end points of atherosclerosis, such as carotid
IMT, clinical events did not differ between the two groups. Indeed, there
were higher adverse events related to medications in the aggressively
treated group. Nevertheless, the fact that measures of atherosclerosis can
be reversed with medication is very interesting and of fundamental
biologic importance.
The Rupture Rate of Large Abdominal Aortic Aneurysms: Is This
Modified by Anatomic Suitability for Endovascular Repair?
Powell JT, Brown LC, Greenhalgh RM, et al; The EVAR Trial Participants.
Ann Surg 2008;247:173-9.
Conclusion: The presence of diabetes, an aneurysm suitable for endo-
vascular aneurysm repair, and statin medications may lower rupture risk of
abdominal aortic aneurysm (AAA).
Summary: The authors used a literature review to systematically deter-
mine rupture rates of AAAs with initial diameters 5 cm in patients not
considered for open repair. The data were stratified with respect to aneurysm
diameter (6.0 cm and 6.0 cm) and gender, and combined using a
random-effects meta-analysis. Post-hoc analyses were also performed. The
effect of gender, diabetes, initial AAA diameter, sac length, and aneurysm
neck were analyzed with proportional hazards models and regression tech-
niques. Data were also stratified by whether patients were suitable for
endovascular repair (EVAR).
The authors identified two prospective, two retrospective, and one
mixed study for inclusion in the meta-analysis. Patients who had AAA repair
were excluded. The overall pooled rupture rate was 18.2 (95% confidence
interval [CI], 13.7-24.1) per 100 patient-years. When the aneurysm in-
creased to 6.0 cm, there was a twofold increase in rupture rate vs aneu-
rysms6 cm (hazard ratio [HR], 2.54; 95% CI, 1.69-3.85). Pooled rupture
rates were not significantly higher in women than men. In patients suitable
for EVAR from the EVAR-2 trial, rupture rate for a 6-cm AAA was 17.4
(95% CI, 12.6-23.4) per 100 patient-years. This was lower than the pooled
rate for all five studies (rupture rate, 27.0; 95% CI, 21.1-34.7) per 100
patient-years (P  .026). Patients with diabetes appeared to have a lower
rupture rate, and a post hoc analysis indicated that patients taking statins at
baseline appeared to have about half the rupture risk compared with those
not taking statins. The crude HR for rupture for patients taking statins was
0.52 (95% CI, 0.27-0.98; P  .044).
Comment: There are a number of interesting findings in this meta-
analysis. Rupture rates for men and women were not significantly different,
suggesting that in larger aneurysms, the effect of sex differences may be
overwhelmed by aneurysm diameter. In addition, short-necked aneurysms
appeared to rupture more often than longer-necked aneurysms, suggesting
that part of the benefit of EVARmay be due to the physical characteristics of
the aneurysm suitable for EVAR. Perhaps most interesting was that post hoc
analysis revealed a potentially great effect for statins in reducing the risk of
AAA rupture. This last point, in particular, deserves greater investigation.
Results in a Consecutive Series of 83 Surgical Corrections of Symp-
tomatic Stenotic Kinking of the Internal Carotid Artery
Illuminati G, Ricco JB, Caliò FG, et al. Surgery 2008;143:134-9.
Conclusion: Surgical correction for symptomatic kinking of the inter-
nal carotid artery (ICA) is safe, effectively relieves hemispheric symptoms,
and prevents stroke.
Summary: The authors sought to evaluate the efficacy of surgical
correction of ICA kinking. Patients in this consecutive series of 81 patients
(mean age, 64 years) all had hemispheric symptoms and were all on anti-
platelet therapy. They underwent 83 surgical procedures to correct ICA
kinking. Procedures used included shortening and reimplanting the vessel
on the common carotid artery, interposition bypass grafts, or transposing the
ICA onto the external carotid artery.Mean follow-up was 56months (range,
15-135 months). The primary end points were 30-day mortality and any
stroke during follow-up. There were no operative deaths. Operative stroke
rate was 1%. Primary patency of the reconstruction was 89%  4.1% at 5
years. At 5 years, freedom from neurologic symptoms was 92% 4% and late
survival was 71%  6%.
Comment: It is important to recognize what the authors are operating
on and what they are not operating on. These were kinked arteries, with
resulting high-grade stenotic lesions. Elongated, tortuous, or coiled arteries
were not included. The article provides good technical descriptions of the
operations performed to correct stenotic kinks; however, because this is
basically a case series, its overall level of evidence must be considered low.
One has to wonder why so many patients with this relatively odd problem
ended up at a single center. Nevertheless, this is a large series by
experienced surgeons and certainly worth reading. It makes one re-
examine the role of high-grade ICA kinks with respect to the production
of neurologic symptoms.
Grading Carotid Intrastent Restenosis: A Six-Year Follow-Up Study
Setacci C, Chisci E, Setacci F, et al. Stroke 2008;30:1189-96.
Conclusion:Duplex ultrasound imaging can accurately predict intras-
tent restenosis of stented carotid arteries.
Summary: The authors sought to establish duplex criteria for intras-
tent restenosis after carotid artery stenting (CAS). Duplex velocity parame-
ters were compared with angiography. This was a 6-year study with data
obtained prospectively. After CAS, patients underwent angiography for
suspected intrastent restenosis. Stenosis was calculated according to the
North American Symptomatic Carotid Endarterectomy Trial (NASCET)
method. Angiographic stenosis was then compared with peak systolic veloc-
ity (PSV), end diastolic velocity (EDV), and the ratio between the peak
systolic velocity of the internal carotid artery and common carotid artery
(ICA/CCA). The initial duplex study was done48 hours after angioplasty
and served as a baseline result. Follow-up duplex examinations were per-
formed at 30 days, 3,6, 9, and 12 months, and then yearly. If the PSV
increased greater than three times the baseline value, or if a PSV200 cm/s
was detected in the stented carotid artery, the patients underwent angiog-
raphy.
There were 814 carotid stent procedures performed. There were 6427
ultrasound examinations and 1123 angiographic studies performed in fol-
low-up. Angiographic intrastent restenosis 70% was detected in 22 and
intrastent restenosis 50% in 73. On the basis of comparisons of duplex
values and angiograms, velocity criteria for grading carotid intrastent reste-
nosis were 30% stenosis, PSV 104 cm/s; 30% to 50% stenosis, PSV 105
to 174 cm/s; 50% to 70% stenosis, PSV175 to 299 cm/s;70% stenosis,
PSV 300 cm/s, EDV 140 cm/s, and an ICA/CCA ratio 3.8.
Comment: This is arguably, to date, the best article in the literature
correlating angiographic findings with duplex findings in patients with
intrastent carotid stenosis. It certainly has the largest numbers. It is
interesting that the criteria for very-high-grade stenosis (70%) differ
very little from those reasonably well accepted for native artery stenosis.
More moderate lesions in stented carotid arteries, however, appear to be
associated with higher PSVs than would be anticipated from comparisons
of angiograms and native internal carotid artery stenoses. One relative
weakness of the current study, and all studies on this subject, is the small
number of patients with 70% angiographic restenosis, 11.7% of a total
of 814 patients.
Competence Assessment of Senior Vascular Trainees using a Carotid
Endarterectomy Bench Model
Black SA, Harrison RH, Horrucks EJ, et al. Br J Surgery 2007: 94;1226-31.
Conclusion: Performance on bench models may provide information
regarding the suitability of surgical trainees to proceed to operative training
in a competency-based training assessment program.
Summary: Objective methods to assess technical competence are
being introduced to surgical training. In this study the authors evaluated
the value of bench top technical skills assessment using a synthetic carotid
endarterectomy (CEA) model. Surgeons in training and attending vas-
JOURNAL OF VASCULAR SURGERY
Volume 48, Number 1 Abstracts 247


The Rupture Rate of Large Abdominal Aortic Aneurysms: Is This Modified by Anatomic Suitability for Endovascular Repair? 

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The Rupture Rate of Large Abdominal Aortic Aneurysms: Is This Modified by Anatomic Suitability for Endovascular Repair?

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