Concomitant peripheral vascular and coronary artery disease: a new dimension for the global endovascular specialist?

Thoracic aorta atherosclerosis burden index predicts coronary artery disease in patients undergoing transesophageal echocardiography

AIMS

The severity of thoracic aortic atherosclerosis (TAA) is associated with the extent of coronary artery disease (CAD). The aim of this study is to quantitative this relationship by developing a novel atherosclerotic index.

METHODS AND RESULTS

Two hundred and forty six consecutive patients underwent transesophageal echocardiography (TEE) and coronary angiography. A grading system was used to define the extent of TAA for individual segment of the thoracic aorta. TAA burden index (TAABI) was defined as the sum of the grading for each segment. Of the derived values TAABI had the greatest specificity and sensitivity in predicting CAD. A TAABI of greater than 6 was associated with 16-fold increase in the probability of CAD with a specificity of 88% and a sensitivity of 81%. The positive predictive value was 77% and the negative predictive value 90%.

CONCLUSION

A TAABI value of greater than 6 accurately predicts the presence of CAD. Patients with no or mild TAA are at low risk of having angiographically significant CAD.

Whole-body screening of atherosclerosis with magnetic resonance angiography

With whole-body magnetic resonance angiography (WBMRA), it is possible to examine the whole arterial tree except intracranial and coronary vessels in a single examination without the risks involved in ionizing radiation or arterial cannulation. Whole-body magnetic resonance angiography is well suited for repeated clinical examinations in patients with systemic diseases such as vasculitis or atherosclerosis and can also be used for scientific purposes. On the basis of the WBMRA overview, a possible further development of the WBMRA concept can be to perform further acquisitions at sites with atherosclerotic plaques with higher-resolution scans to determine the degree of stenosis more accurately or to achieve plaque characterization. A total validation of WBMRA compared with digital subtraction angiography (DSA) is not possible owing to the hazards of ionizing radiation. Studies have shown a high sensitivity and specificity for the pelvic and lower limb arteries in comparison with DSA. No systematic validation against DSA has been performed for the renal, aortic, and carotid arteries. Various methods have been used, however, for confirmation of vascular abnormalities found on WBMRA such as ultrasonography, dedicated MRA, or DSA, with reasonably high agreement. The WBMRA method has not been studied with regard to prediction of future cardiovascular (CV) events, as have intima media thickness, coronary artery calcium scoring, and the ankle-brachial index. The full usefulness of WBMRA in an epidemiological setting and as a complementary screening tool for assessing CV risk still needs to be validated against future CV events.

Diagnostic value of carotid intima-media thickness in indicating multi-level atherosclerosis

Carotid intima-media thickness (CIMT) is an indicator of atherosclerosis, but its association with multi-level involvement is sparsely investigated. Study aimed to examine interrelation between CIMT and number of arterial territories with significant (>50%) stenoses, including coronary, supraaortic, renal and iliac/femoral arteries.

METHODS AND RESULTS

Study formed 415 patients (294 men), aged 62.9+/-9.3 years referred to coronary angiography. CIMT assessment was performed in common, bulb and internal carotid segments, and expressed as the mean aggregate value. In all patients, both coronary, renal angiography and supraaortic, iliac/femoral arteries ultrasound was performed. Group I formed 102 patients without significant lesions in any of investigated territories; group II formed 131 patients with single territory; group III formed 102 patients with two territory and group IV formed 80 patients with three to four territory involvements. CIMT correlated with increasing number of involved territories (r=0.751, p<0.001). Aggregate CIMT, previous myocardial infarction, creatinine level, hypertension, hs-CRP, smoking were independent predictors of multi-level involvement (p<0.001, R=0.768). ROC curves showed that CIMT cut-off value of 1.308 mm could distinguish 0-1 from two to three level involvement with sensitivity of 81.6%, specificity 88.8%, PPV 85.1%, NPV 86.3% (odds ratio 35.9, range 20-65).

CONCLUSIONS

CIMT increases with number of involved territories. CIMT is an independent predictor of significant multi-level atherosclerosis, showing high sensitivity and specificity for indicating more advanced territorial atherosclerotic involvement.

[Prevalence of renal artery stenosis in patients with critical limb ischemia]

BACKGROUND AND OBJECTIVE

Our purpose was to evaluate the prevalence of renal artery stenosis in patients with critical limb ischemia and to study any clinical or laboratory indicator that could predict this association.

PATIENTS AND METHOD

One hundred consecutive patients with critical limb ischemia evaluated by angiogram were included in the study from January to July 2003. Cardiovascular risk factors and renal function were analyzed.

RESULTS

One hundred angiographic studies have been analyzed. Thirty nine (39%) of our patients had some type of pathology of the renal artery but the rest, 61 (61%), had normal and healthy renal arteries. In 5 patients, a bilateral renal pathology was found. Severe disease (> 60% stenosis, bilateral or renal occlusion) was present in 15 cases including 6 occlusions. Once we compared the patients with healthy renal arteries with the patients with different degrees of stenosis, we did not appreciate significant differences in hypertension, diabetes, coronary disease or smoking habit, nor with laboratory data such as creatinine, urea, c-reactive protein, total cholesterol or atherogenic index. No differences were found either comparing patients with normal renal artery with patients with bilateral pathology or with unilateral occlusion.

CONCLUSIONS

There is a high prevalence of renal artery pathology in patients with critical limb ischemia although we have not found any clinical or laboratory factors useful to identify them.

The Prevalence and Quantification of Atherosclerosis in an Elderly Population Assessed by Whole-Body Magnetic Resonance Angiography

OBJECTIVE

The principal aim of the present study was to explore the feasibility of using whole-body magnetic resonance angiography to assess atherosclerosis in different vascular territories in a cohort of elderly.

METHODS AND RESULTS

Three hundred six 70-year-old subjects (145 women, 161 men) recruited from a population-based cohort study (Prospective Investigation of the Vasculature in Uppsala Seniors, ie, the PIVUS study) underwent 1.5-T whole-body magnetic resonance angiography with gadodiamide. The arteries were divided into 26 segments. In total, 7956 vessel segments were evaluated with 7900 segments (99.3%) possible to evaluate. Of these, 7186 segments (91%) were normal. Luminal narrowing of > or = 50% was observed in 9 (1.5%) of the renal arteries, 12 (1.8%) of the carotid arteries, in 31 segments (1.1%) of the pelvic/upper leg territories, and in 136 segments (6.2%) of territories in the lower leg. Approximately one-third of the sample had no vascular abnormalities, one-third had stenoses of < 50%, and the remainder had stenoses > or = 50% or occlusions. Six subjects (2%) had aortic aneurysms. In subjects without evident vascular disease, 26% had significant vascular abnormalities.

CONCLUSIONS

Whole-body magnetic resonance angiography performed with a clinical scanner can be used for quantifying atherosclerosis in different vascular territories in a single examination in an elderly population.

Effective prevention of massive periprocedural embolism during renal artery stenting

We report the case of a massive embolism of atheromatous material during stenting of a tight renal artery stenosis, which was prevented by using a distal embolic protection device and aggressive aspiration of the blood through a guiding catheter. A 72-year-old man who was referred to our institution for coronary artery disease treated with coronary angioplasty underwent renal angiography which revealed a tight stenosis (99%) located at the ostium of the right renal artery extending for 15 mm into the main tract. The diameter of the artery was estimated to be 5.5 cm in the main tract, and the plaque had a soft appearance complicated by the presence of a thrombus (persistence of contrast agent in the plaque on selective renal angiography). Renal artery Doppler ultrasound and renal scintigraphy confirmed the need for renal revascularization. An embolus protection device (FilterWire EZ, Boston Scientific, Natick, MA, USA) was successfully opened distally to the stenosis after gentle predilation. After stent deployment (Genesis 5.5x18 mm, Cordis, J&J Medical, Miami Lakes, FL, USA), aggressive aspiration of the blood through the guiding catheter was performed. A large amount of embolic material with macroscopic particles was retrieved into the basket of the embolic protection device and in the blood aspirated with the guiding catheter. Good functional results were obtained on Doppler analysis of intrarenal blood flow, with a resistive index of 70. Despite the fact that the extensive use of embolic protection devices in renal artery stenting is still under discussion, this technique may be advisable in selected cases with favorable anatomy and high embolic risk, especially in patients with complex and hazy lesions.