Noninvasive assessment of the prevalence and characteristics of coronary atherosclerotic plaques by multidetector computed tomography in asymptomatic type 2 diabetic patients at high risk of significant coronary artery disease: a preliminary study.

BACKGROUND: There is a need to identify diabetic patients at risk of cardiovascular events before symptom onset. AIMS: To evaluate the prevalence and characteristics of coronary atherosclerotic plaques in asymptomatic type 2 diabetic patients with coronary risk factors but without known coronary artery disease, using multidetector computed tomography. METHODS: High-resolution 40-slice coronary computed tomography was performed prospectively in 42 consecutive type 2 diabetic patients (mean age 62 years; range 50-77 years; 28 men) with over one or more carotid atherosclerotic plaque and no coronary artery disease symptoms. Computed tomography data were evaluated for calcium score and the presence of coronary plaques. Plaque type, distribution, extensive character and obstructive nature were determined per patient for each segment. RESULTS: No plaques were detected in 11 (26.2%) patients. Atherosclerotic plaques were detected in 31 (73.8%) patients. A total of 147 coronary segments with plaque were identified, of which 11 (7.5%) contained hypodense plaques, 28 (19%) mixed plaques and 108 (73.5%) calcified plaques. Hypodense plaques were noted in 4/15 (26.7%) patients without coronary calcifications. Most calcified and hypodense plaques resulted in lumen narrowing of less than 50%; most mixed plaques resulted in lumen narrowing greater than 50%. Obstructive disease was detected in 9/11 patients with a high calcium score (>400). CONCLUSION: This preliminary study demonstrates that a high proportion of asymptomatic type 2 diabetic patients present without coronary plaques detectable by multidetector computed tomography, despite concomitant carotid atherosclerotic lesions. Computed tomography seems to detect a high proportion of plaques compared with conventional angiography in these specific patients.

Assessment of acute myocardial infarction using MDCT after percutaneous coronary intervention: comparison with MRI.

OBJECTIVE: Imaging to determine myocardial infarct size is difficult in the emergency setting because the current gold standards, MRI and nuclear medicine techniques, are difficult to perform in unstable patients. Delayed enhanced MDCT has recently been proposed as a technique to study contrast uptake in infarcted myocardium. In this study, we compared the extent of acute myocardial infarction as measured by delayed enhanced MDCT performed immediately after percutaneous coronary intervention (PCI) without an additional iodine injection with that measured by delayed gadolinium-enhanced MRI. SUBJECTS AND METHODS: Nineteen consecutive patients presenting with primary acute myocardial infarction underwent delayed enhanced MDCT immediately after coronary angioplasty and underwent delayed enhanced MRI within 8 days of angioplasty. Only patients with a thrombolysis in myocardial infarction (TIMI) score of 0 or 1 of the culprit coronary artery before endovascular angioplasty and TIMI score of 2 or 3 after angioplasty were selected. Comparison of delayed enhanced MDCT and delayed enhanced MRI was performed by three observers and focused on identifying the involved segments and determining the transmural extent of enhancement and infarct size. RESULTS: The mean signal intensity was significantly higher in the involved territory than in healthy myocardium: 197 +/- 81 H versus 71 +/- 20 H, respectively (p < 0.0001). We found significant agreement between delayed enhanced MDCT and delayed enhanced MRI for the number of involved segments, transmural extent of enhancement, and infarct size (r(2) = 0.74, 0.76, and 0.67, respectively; p < 0.0001) with good interobserver reproducibility (kappa = 0.8). CONCLUSION: The results of our study show that delayed enhanced MDCT allows accurate visualization of early myocardial contrast uptake compared with delayed enhanced MRI and does not require an additional contrast injection after PCI.

Primary angioplasty is cost-minimizing compared with pre-hospital thrombolysis for patients within 60 min of a percutaneous coronary intervention center: the Comparison of Angioplasty and Pre-hospital Thrombolysis in Acute Myocardial Infarction (CAPTIM) cost-efficacy sub-study.

OBJECTIVES: This ancillary study of the Comparison of Angioplasty and Pre-hospital Thrombolysis in Acute Myocardial Infarction (CAPTIM) trial sought to assess the cost-efficacy ratio of primary coronary angioplasty (PCA) and pre-hospital thrombolysis (PHT) in patients suffering from an acute myocardial infarction (AMI) (<6 h) close to (<60 min journey) a percutaneous coronary intervention (PCI) center. BACKGROUND: In the CAPTIM study, at 30 days follow-up PCA was as equally effective as PHT with rescue angioplasty if needed. The cost efficacy of these two strategies has not yet been compared. METHODS: Data were prospectively collected for 299 patients in three centers. The efficacy analysis was extended at one-year follow-up for those patients. Direct fixed and variable actual costs were assessed with a piggyback data collection. RESULTS: The one-year primary end point event-rate (death, non-fatal myocardial infarction, and stroke) was not different after PCA or PHT (14% vs. 16. 4%, p = NS). Costs were lower in the PCA group either during the in-hospital period (8,287 vs. 9,170 $, p = 0.0001) and after one-year follow-up, in relation to a higher rate of subsequent revascularizations in the PHT group (49% vs. 23%, p < 0. 01), leading to a longer hospital stay (10 vs. 9.1 days, p = 0. 03). CONCLUSIONS: After AMI in patients less than 1 h from a PCI center, PCA is as effective and less costly than a combined strategy of PHT followed by rescue angioplasty.

150 microgram intracoronary adenosine bolus for accurate fractional flow reserve assessment of angiographically intermediate coronary stenosis.

AIMS: Fractional flow reserve measurement is based upon achieving maximum hyperemia. A 40 microg intracoronary (IC) adenosine bolus sometimes seems insufficient, and we therefore sought to assess the possible role of 100-150 microg boli in routine. METHODS AND RESULTS: 108 intermediate (49+/-16%) stenoses were consecutively studied with 6F catheters. A history of myocardial infarction in the territory of the explored artery or myocardial hypertrophy were the exclusion criteria. Mean FFR was 0.82+/-0.12 with a 40 microg adenosine bolus and decreased to 0.80+/-0.12 and 0.80+/-13 respectively with 100microg and 150 microg boli (P<0.001 vs 40microg in both cases; 100 vs 150 microg, NS). The 40 microg bolus failed to diagnose 8 out of 30 (27%) significant stenoses (i.e., final FFR <0.75). The large boli led to 12 (11%) transient asymptomatic and spontaneously resolving AV blocks without other side-effects. CONCLUSION: FFR underestimated a quarter of intermediate stenoses with the currently used 40microg IC adenosine bolus. A large bolus up to 150 microg appears to be accurate and safe for routine FFR measurement.