Accuracy of 64-slice coronary CT angiography in predicting percentage diameter stenosis.

OBJECTIVE: Aim of our study was to evaluate the diagnostic accuracy of 64-slice CT coronary angiogram in measuring the percentage diameter stenosis compared to invasive angiography. METHODS AND RESULTS: 100 consecutive patients with more than 50% stenosis in at least one major coronary artery measured by 64-slice CT angiogram were included in the study. Patients with atrial fibrillation, history of allergy to contrast agent, acute coronary syndrome, renal insufficiency, history of previous coronary bypass surgery or percutaneous transluminal coronary stent, heart rate more than 70 per minute at the time of scan in spite of beta-blocker therapy, and calcium score >2000 Agaston units were not included in the study. 15-segment American Heart Association classification was used, and segments were compared using qualitative angiography. 192 segments (12.80%) could not be assessed due to poor image quality. The major cause for poor image quality was dense calcification precluding the luminal assessment (60.42%). Comparing the maximal percentage diameter stenosis by 64-slice CT versus invasive angiogram, the Spearman correlation coefficient between the two modalities was 0.788 and p value was <0.001. Bland-Altman analysis showed a mean difference in percentage stenosis of 2.1 +/- 16.22%. A total of 91.97% (401 of 436) of segments were within 1.96 standard deviations. CONCLUSION: This study shows that 64-slice CT coronary angiogram is accurate in detecting percentage diameter stenosis compared to coronary angiogram if the image quality is good. Calcifications and motion artifacts are the main culprits of poor image quality.

Outcomes of carotid artery stenting in patients with symptomatic and asymptomatic carotid artery stenosis.

OBJECTIVE: Carotid endarterectomy is superior to medical therapy in patients with significant extracranial carotid artery stenosis. This modality of treatment has its own complications. The principal objective of this study is to assess efficacy, feasibility and outcomes of carotid artery stenting in both symptomatic and asymptomatic carotid artery stenosis. METHODS: Our study is a retrospective analysis of 45 consecutive patients with 56 lesions who underwent carotid angioplasty with stenting from January 2000 to June 2007 for carotid artery stenosis of more than 70%. All patients underwent detailed neurological examination and carotid Doppler evaluation by using Sonos 5500. Computed tomography of brain was done in those patients who were symptomatic in the past. RESULTS: The mean age of the study population was 65 +/- 9.2 years. There were 34 (79%) patients with coronary artery disease and out of them 31 (68%) patients had undergone coronary artery bypass grafting. All patients with common carotid artery, 13 (81%) patients with right internal carotid stenosis and 12 (66%) patients with left internal carotid artery stenosis had ostioproximal stenosis. Contralateral lesion was found in 9 patients and 2 patients had total occlusion. There were no post-procedural neurological events. Only one patient died in our study population due to non-cerebral cause. CONCLUSION: Carotid artery stenting is a safe procedure. The 30 days' outcomes are similar in both symptomatic and asymptomatic patients with significant carotid artery stenosis.