Incidence of severe coronary stenosis in asymptomatic patients with peripheral arterial disease scheduled for major vascular surgery.

BACKGROUND: Peripheral arterial disease (PAD) has the risk equivalent of coronary heart disease. The biochemical parameters associated with functionally significant coronary artery stenosis were investigated in asymptomatic patients with PAD who were scheduled for major vascular intervention. METHODS: A total of 50 PAD patients asymptomatic for coronary heart disease were examined using coronary computed tomography angiography (CTA). A stress myocardial CT perfusion (CTP) test was performed in patients who exhibited coronary stenosis >40%. In patients with stress-induced perfusion defects, the severity of stenosis was assessed using invasive coronary angiography including fractional flow reserve assessment. The CT findings were correlated with both classical and more recently developed parameters of atherosclerosis. RESULTS: According to the combined CT examination (CTA and stress CT perfusion), 36% of patients exhibited significant coronary stenosis. Stress-induced hypoperfusion was observed in 95.7% of severe stenotic lesions. After adjustment for confounders, the level of high-sensitivity troponin I was associated with severe coronary stenosis (OR 1.260 [95% CI 1.054 to 1.505]). Other biochemical parameters did not correlate with coronary stenosis. The annual mortality rate was 4%. CONCLUSIONS: The results of the present study confirm a significant diagnostic contribution of a complex cardiac CT examination in patients scheduled for major vascular surgery. A high prevalence of asymptomatic coronary heart disease was observed in this particular patient group. High-sensitivity measurements of troponin I correlated with the extent of the coronary stenosis.

Regadenoson-Stress Dynamic Myocardial Perfusion Improves Diagnostic Performance of CT Angiography in Assessment of Intermediate Coronary Artery Stenosis in Asymptomatic Patients.

The prospective study included 54 asymptomatic high-risk patients who underwent coronary CT angiography (CTA) and regadenoson-induced stress CT perfusion (rsCTP). Diagnostic accuracy of significant stenosis (≥50%) determination was evaluated for CTA alone and CTA + rsCTP in 27 patients referred to ICA due to the positive rsCTP findings. Combined evaluation of CTA + rsCTP had higher diagnostic accuracy over CTA alone (per-segment: specificity 96 versus 68%, p = 0.002; per-vessel: specificity 95 versus 75%, p = 0.012) and high overruling rate of rsCTP was proved in intermediate stenosis (40-70%). Results demonstrate a significant additional value of rsCTP in the assessment of intermediate coronary artery stenosis found with CTA.

Low contrast volume run-off CT angiography with optimized scan time based on double-level test bolus technique--feasibility study.

PURPOSE: To verify the technical feasibility of low contrast volume (40 mL) run-off CT angiography (run-off CTA) with the individual scan time optimization based on double-level test bolus technique. MATERIALS AND METHODS: A prospective study of 92 consecutive patients who underwent run-off CTA performed with 40 mL of contrast medium (injection rate of 6 mL/s) and optimized scan times on a second generation of dual-source CT. Individual optimized scan times were calculated from aortopopliteal transit times obtained on the basis of double-level test bolus technique--the single injection of 10 mL test bolus and dynamic acquisitions in two levels (abdominal aorta and popliteal arteries). Intraluminal attenuation (HU) was measured in 6 levels (aorta, iliac, femoral and popliteal arteries, middle and distal lower-legs) and subjective quality (3-point score) was assessed. Relations of image quality, test bolus parameters and arterial circulation involvement were analyzed. RESULTS: High mean attenuation (HU) values (468; 437; 442; 440; 342; 274) and quality score in all monitored levels was achieved. In 91 patients (0.99) the sufficient diagnostic quality (score 1-2) in aorta, iliac and femoral arteries was determined. A total of 6 patients (0.07) were not evaluable in distal lower-legs. Only the weak indirect correlation of image quality and test-bolus parameters was proved in iliac, femoral and popliteal levels (r values: -0.263, -0.298 and -0.254). The statistically significant difference of the test-bolus parameters and image quality was proved in patients with occlusive and aneurysmal disease. CONCLUSION: We proved the technical feasibility and sufficient quality of run-off CTA with low volume of contrast medium and optimized scan time according to aortopopliteal transit time calculated from double-level test bolus.

Efficacy and safety of transient ulnar artery compression to recanalize acute radial artery occlusion after transradial catheterization.

Radial artery occlusion (RAO) can result from transradial catheterization. We compared the incidence of RAO with 2 heparin dosage regimens after transradial coronary angiography, and we evaluated the efficacy and safety of transient homolateral ulnar artery compression to achieve acute radial artery recanalization. Patients referred for coronary angiography were randomized to very-low-dose heparin (2,000 IU) or low-dose heparin (5,000 IU). On sheath removal, hemostasis was obtained using the TR band with a plethysmography-guided patent hemostasis technique. In the case of RAO as assessed by duplex ultrasonography 3 to 4 hours after hemostasis, immediate 1-hour ulnar artery compression was applied. Hematomas >15 cm(2) were also assessed. We randomized 465 patients, 222 in the 2,000-IU group and 243 in the 5,000-IU group. The baseline and procedural characteristics were comparable in both groups. The incidence of initial RAO was 5.9% in the 2,000-IU group and 2.9% in the 5,000-IU group (p = 0.17), with a compression time of 2.10 ± 0.78 hours and 2.25 ± 0.82 hours, respectively (p = 0.051). After ulnar artery compression, the final incidence of RAO was 4.1% in the 2,000-IU group and 0.8% in the 5,000-IU group (p = 0.03). The incidence of local hematoma was 2.3% and 3.7% in the 2,000- and 5,000-IU groups, respectively (p = 0.42). In conclusion, acute RAO after transradial catheterization can be recanalized by early 1-hour homolateral ulnar artery compression. This simple nonpharmacologic method was effective and safe in patients with very-low- and low-dose heparin. Nevertheless, the incidence of final RAO remained significantly lower after a higher anticoagulation level.