Assessment of the Image Quality and Diagnostic Accuracy of Coronary CT Angiography: Effect of Sublingual Administration of Nitroglycerin

PURPOSE: We wanted to investigate the effect of sublingual nitroglycerin (NTG) on improving the image quality and diagnostic accuracy of coronary computed tomographic angiography (CTA) for detecting atherosclerosis and significant stenosis. MATERIALS AND METHODS: We retrospectively assessed the data of 81 patients who underwent coronary CTA. Forty three patients underwent coronary CTA without medication (the non-administrated group), while 38 patients were given 0.6 mg NTG sublingually before coronary CTA (the administrated group). Image quality was assessed using a five-point grading scale. We evaluated the diagnostic performance of coronary CTA for assessing atherosclerosis and significant stenosis (> or = 50%) in the 42 patients who underwent invasive coronary angiography. RESULTS: The mean image-quality grades were 4.09+/-0.72 and 4.50+/-0.60 in the non-administrated and administrated groups, respectively (p=0.008). On the per-artery analysis, the accuracy percentages for detecting coronary CTA were 65 and 88% for atherosclerosis and 82 and 80% for significant stenosis in the non-administrated and administrated groups, respectively. On the per-patient analysis, the positive predictive values for coronary CTA were 80% and 100% for atherosclerosis and 77% and 88% for significant stenosis in the non-administrated and administrated groups, respectively. CONCLUSION: Coronary CTA with NTG administration improved the image quality. The accuracy of coronary CTA for detecting atherosclerosis was higher in the administrated group than in the non-administrated group.

The Usefulness of Stress Perfusion MR using Steady State Free Precession Sequence for Depiction of Significant Coronary Artery Stenosis

PURPOSE: To evaluate the technical performance of stress myocardial perfusion magnetic resonance (MR) imaging using saturation-recovery steady-state free precession (SR- SSFP) and to assess the diagnostic accuracy of this examination for depiction of significant coronary artery stenosis. MATERIALS AND METHODS: 167 patients underwent stress myocardial perfusion MR imaging at rest and adenosine-induced stress by using a 1.5-T cardiac MR imaging unit. The first-pass MR perfusion was performed using SR-SSFP sequence. Coronary angiography was performed in 113 patients. Image analysis was performed to compare the diagnostic accuracy of MR imaging with that of coronary angiography. RESULTS: During the MR examination, minor side effects of adenosine-induced stress occurred, most commonly chest discomfort (29%), followed by dyspnea (4%), and facial flushing (0.8%). The overall sensitivity of MR imaging for depicting at least one coronary artery with significant stenosis was 91%. The sensitivities of MR imaging for depiction of stenoses were as follows: 80% for single-vessel stenosis, 81% for double-vessel stenosis, and 100% for triple-vessel stenosis.. The specificity of MR imaging for identification of patients with significant coronary artery stenosis was 78%. CONCLUSION: Stress myocardial magnetic resonance (MR) perfusion imaging using SR-SSFP sequence is safe and useful for the detection of significant coronary artery disease.

The Usefulness of Stress Perfusion MR using Steady State Free Precession Sequence for Depiction of Significant Coronary Artery Stenosis

PURPOSE: To evaluate the technical performance of stress myocardial perfusion magnetic resonance (MR) imaging using saturation-recovery steady-state free precession (SR- SSFP) and to assess the diagnostic accuracy of this examination for depiction of significant coronary artery stenosis. MATERIALS AND METHODS: 167 patients underwent stress myocardial perfusion MR imaging at rest and adenosine-induced stress by using a 1.5-T cardiac MR imaging unit. The first-pass MR perfusion was performed using SR-SSFP sequence. Coronary angiography was performed in 113 patients. Image analysis was performed to compare the diagnostic accuracy of MR imaging with that of coronary angiography. RESULTS: During the MR examination, minor side effects of adenosine-induced stress occurred, most commonly chest discomfort (29%), followed by dyspnea (4%), and facial flushing (0.8%). The overall sensitivity of MR imaging for depicting at least one coronary artery with significant stenosis was 91%. The sensitivities of MR imaging for depiction of stenoses were as follows: 80% for single-vessel stenosis, 81% for double-vessel stenosis, and 100% for triple-vessel stenosis.. The specificity of MR imaging for identification of patients with significant coronary artery stenosis was 78%. CONCLUSION: Stress myocardial magnetic resonance (MR) perfusion imaging using SR-SSFP sequence is safe and useful for the detection of significant coronary artery disease.

Coronary to Bronchial Artery Communication

PURPOSE: To analyze the cineangiographic appearance and determine the clinical importance of coronary-to-bronchial artery communication. MATERIALS AND METHODS: The coronary cineangiograms of 4,620 patients were reviewed, and 12 cases of coronary-to-bronchial artery communications were observed in 10 patients (M:F=6:4; mean age, 48.4 years). The cineangiographic findings were analyzed and correlated with these of other imaging studies [perfusion scan (n=5), computed tomographic angiography (CTA) (n=4), conventional chest computed tomography (CT) (n=1), and conventional angiography (n=6)]. RESULT: Cineangiography revealed that hypertrophied branches of the coronary artery communicated with bronchial arteries in which adjacent hypervascular staining, was observed, and which were accompanied by pulmonary shunts (n=9). The underlying diseases identified among the ten patients were Takayasu arteritis (n=5), chronic inflammatory pulmonary disease (n=3), pulmonary thromboembolism (n=1), and or newly diagnosed pulmonary tuberculosis (n=1). The lung fields supplied by coronary-to-bronchial communication showed close correlation with the territories of perfusion defects, decreased pulmonary vascularity, or inflammatory lesions revealed by other imaging studies. CONCLUSION: Coronary-to-bronchial artery communication can present as a secondary result of occlusive disease of the pulmonary arteries or chronic pulmonary inflammation, and in patients with hemoptysis involving, for example, incomplete embolization or myocardiac infarction, it may be problematic.

Correlation Between Obstructive Coronary Artery Disease and Electron Beam Tomography Coronary Artery CalciumScan

PURPOSE: To determine the correlation between obstructive coronary artery disease and electron beamtomography coronary artery calcium(EBT CAC) scan and to measure the difference in calcium score according tosymptoms. MATERIALS AND METHODS: Fifty-six patients underwent EBT CAC scanning and either coronary angiography orstress thallium 201 scanning or the treadmill test. When the results were positive, coronary artery obstructivedisease(CAOD) was assumed to be present. The patients were divided into three groups : symptomatic CAOD,asymptomatic CAOD, and asymptomatic non- CAOD; those with a previous history of myocardial ischemia or who showedpositive results in any of the three tests relating to typical symptoms of angina were assigned to the symptomaticgroup. RESULTS: The number of cases assigned to group to group 1,2 and 3 was 19, 16 and 21, respectively; totalCAC scores were 571+/-751, 600+/-726 293+/-401, respectively. The difference in CAC score between asymptomatic CAODand asymptomatic non- CAOD was not statistically significant(p=0.079) but in asymptomatic CAOD, the score tendedto be higher. The CAC score was not different between symptomatic and asymptomatic CAOD(p>0.1). When the CACthreshold was 1, sensitivity was 89% and specificity was 14%;when the threshold was 200, sensitivity was 60% andspecificity was 67%. CONCLUSION: When the EBT CAC score is high, further evaluation provides early evidence ofcoronary artery obstructive disease.