CORONARY ANGIOGRAPHY WITH DUAL SOURCE COMPUTED TOMOGRAPHY:INITIAL EXPERIENCE

Objective To explore the scan technique and image quality of coronary angiography with dual source computed tomography(CT) without oral metoprolol preparation.Methods Plain and enhanced dual source CT coronary angiography without oral metoprolol preparation was prospectively performed in 600 patients.Calcium scoring with plain scan images as well as multi-planar reconstruction(MPR),maximum intensity projection(MIP),and volume rendering technique(VRT) reconstruction with enhanced scan images were performed in all cases.The scan technique and post-reconstruction experience was summarized.The image quality was classified as 1 to 4 points,and coronary segments classified according to the American Heart Association standards were evaluated.Results The average calcium score of the 600 cases was 213.6±298.7(0-3 216.5).The average heart rate of the enhanced scan was 82.1±16.2(47-139) bpm.The post-reconstruction methods with which coronary segments could be shown as best as possible consisted of single phase reconstruction method,two or more phases supplemented method,and electrocardiogram editing method.Altogether 8 457 coronary segments were evaluated,among which 97.2% were evaluated as point 1,1.7% point 2,0.5% point 3,and 0.6% point 4.The coronary segments in 261 cases were completely normal,while 360 segments were diagnosed with <50% stenosis and 625 segments with ≥50% stenosis.Conclusions Excellent coronary artery image can be obtained with dual source CT in patients with any heart rate without oral metoprolol preparation.Heart rate is not a major source of the artifact,coronary segments can be well shown with single or multiple-phase reconstruction method.

Primary percutaneous coronary intervention on older patients with acute ST-segment elevation myocardial infarction: analysis of its risk factors

Objective: The aim of the present study was to assess the early clinical outcome and risk factors in old patients with acute ST elevation myocardial infarction (STEMI) following primary percutaneous coronary intervention (PCI). Methods: A total of 136 patients older than 60 years with STEMI who received successful PCI were included in this study. The patients were classified in 2 age groups: patients ≥75 years and <75 years of age. The extent of coronary artery lesions was measured by quantitative coronary artery angiography (QCA). Subjects were tracked for subsequent cardiovascular events: cardiac death, myocardial infarction, heart failure, percutaneous coronary intervention, coronary artery bypass and stroke. Results: Though the older group had a higher prevalence of adverse baseline characteristics and lower final TIMI flow than patients<75y (P<0.05), the procedural success did not make difference between the two groups. In 12 months follow-up of 136 study participants, there occurred 39 CV events : cardiac death (five patients), heart failure (nineteen patients), and stroke (six patients). Three patients received coronary bypass grafts and six patients underwent PCI. Heart failure and overall cardiovascular event rates were higher in older patients compared with those in patients<75y. The main adverse clinical events (MACE) for the old group were a little higher comparing with the younger in 12-month follow-up (P=0.029 6 and P=0.043 4). Multivariate cox analysis identified that a diagnosis of diabetes (HR 2.495, 95%CI 1.224 to 5.083, P= 0.011 8) and time from symptom(HR 1.450, 95%CI 1.143 to 1.841, P= 0.008 2) to PCI as independent predictors of CV events after adjustment of all entered baseline variables. Conclusion: Our study suggests that drug-eluting stent implantation in older patients with acute ST elevation myocardial infarction has high initial procedural success rates despite having more severe baseline risk characteristics, and to shorten the time from symptom onset to PCI may decrease cardiovascular events in old patients following PCI.