[Screening of asymptomatic coronaropathy with adenosine stress myocardial perfusion MRI: a pilot study]

The aim of the study was to evaluate the incidence of asymptomatic coronary heart disease in patients with cardiovascular risk factors and evaluate the diagnostic value of myocardial stress perfusion magnetic resonance as screening test in these patients. We performed a retrospective analysis of 103 consecutive asymptomatic patients with at least one clinical risk factor for cardiovascular disease, who have undergone myocardial stress perfusion magnetic resonance. For respective evaluation of ischemic myocardium and infracted myocardium, magnetic resonance imaging protocol included the study of both myocardial viability by late enhancement imaging and first-pass perfusion at rest and during maximal stress (adenosine). The reference standard was catheter coronary angiography for 10 patients and clinical follow-up for 93 patients. The incidence of coronary heart disease was 22/103 (21%), including 6/103 (6%) ischemia and 16/103 (15%) infarcts. Respective sensitivity, specificity, negative and positive predictive values for myocardial stress perfusion magnetic resonance in detecting ischemic myocardium were 100, 97, 67 and 100%. Myocardial stress perfusion magnetic resonance can be regarded and further investigated as screening test for the detection of asymptomatic coronary heart disease in high-risk subjects. Prospective studies, larger study groups and cost-effectiveness analysis are needed.

Diagnostic value of exercise electrocardiography and angina after coronary artery stenting. Benestent Study Group

To determine whether metallic stent implantation within a coronary artery modifies the accuracy of angina or exercise test results in predicting stenosis, we studied 172 patients assigned to stent implantation and 153 patients assigned to balloon angioplasty enrolled in the Benestent trial comparing de novo stenting with conventional balloon angioplasty. Sensitivity and specificity curves were constructed for the prediction of percentage diameter stenosis and minimal lumen diameter. Receiver-operator curves were constructed for comparison of diagnostic accuracy. Identical exercise load and duration were achieved in the two groups, despite a better angiographic result in patients treated with a stent. Similarly, the diagnostic accuracy of clinical symptoms or exercise test results as a function of the angiographic results were similar in patients with and patients without a stent. The intersection points of the sensitivity and specificity curves for recurrent angina or ST-segment depression were 72% to 77%. The corresponding cut-off points for percentage diameter stenosis were, respectively, 52% and 50% for patients with and without a stent (1.35 and 1.50 mm for minimal lumen diameter). We conclude that the presence of an intracoronary stent does not affect the diagnostic accuracy of recurrent angina or exercise-induced ST depression in predicting residual stenosis. We also conclude that exercise tolerance is similar after balloon angioplasty, with or without stenting, despite a better angiographic outcome in the group receiving a stent, suggesting a minimal threshold beyond which the patient is no longer at risk for ischemia during exercise.

Variability in estimation of coronary dimensions from 6F and 8F catheters

To investigate the suitability of diagnostic 6F catheters for coronary angiographic measures in the clinical setting, we determined the relative accuracy and reproducibility of the measures obtained with these catheters as scaling devices in 59 stenoses. Comparison was made with duplicate injections, obtained before angioplasty, using an 8F guiding catheter as scaling device. Intra- and interobserver variability was evaluated in 15 stenoses. The coefficient of variation averaged 18.3% for the minimal lumen diameter, 10.4% for the percent stenosis, and only 7.4% for the reference diameter. Reproducibility of angiographic measures done with the 6F catheter was similar to that obtained with the 8F catheter, although accuracy was lower with the 6F for the measurement of reference diameter. Thus, quantitative coronary angiography (QCA) measures derived from routine diagnostic angiograms may be suitable for determination of reference diameter, allowing enough precision for determination of the size of a coronary device for intervention, but these measures may lack accuracy for precise determination of minimum diameter and percent stenosis, making their use questionable in studies looking at individual changes in coronary stenosis dimensions.

Popliteal venous aneurysm: unusual source of pulmonary embolism

Popliteal vein aneurysm is a rare cause of pulmonary embolism. We present the case of a 39-year-old man with multiple pulmonary emboli. Subsequent investigation revealed a saccular aneurysm of the right popliteal vein containing large clots. The presence of fresh thrombus was confirmed at surgery which consisted in excision of the saccular aneurysm with vein patch closure. Primary popliteal venous aneurysms are probably congenital in origin. Phlebography is diagnostic. Surgery is recommended.