Multi-modality imaging for the assessment of myocardial perfusion with emphasis on stress perfusion CT and MR imagingKo, Sung; Hwang, Hweung; Kim, Sung; Cho, Ihn
doi: 10.1007/s10554-015-0645-7pmid: 25809387
High-quality and non-invasive diagnostic tools for assessing myocardial ischemia are necessary for therapeutic decisions regarding coronary artery disease. Myocardial perfusion has been studied using myocardial contrast echo perfusion, single-photon emission computed tomography, positron emission tomography, cardiovascular magnetic resonance, and, more recently, computed tomography. The addition of coronary computed tomography angiography to myocardial perfusion imaging improves the specificity and overall diagnostic accuracy of detecting the hemodynamic significance of coronary artery stenosis. This study reviews the benefits, limitations, and imaging findings of various imaging modalities for assessing myocardial perfusion, with particular emphasis on stress perfusion computed tomography and cardiovascular magnetic resonance imaging.
Image quality and radiation reduction of 320-row area detector CT coronary angiography with optimal tube voltage selection and an automatic exposure control system: comparison with body mass index-adapted protocolLim, Jiyeon; Park, Eun-Ah; Lee, Whal; Shim, Hackjoon; Chung, Jin
doi: 10.1007/s10554-015-0594-1pmid: 25604967
To assess the image quality and radiation exposure of 320-row area detector computed tomography (320-ADCT) coronary angiography with optimal tube voltage selection with the guidance of an automatic exposure control system in comparison with a body mass index (BMI)-adapted protocol. Twenty-two patients (study group) underwent 320-ADCT coronary angiography using an automatic exposure control system with the target standard deviation value of 33 as the image quality index and the lowest possible tube voltage. For comparison, a sex- and BMI-matched group (control group, n = 22) using a BMI-adapted protocol was established. Images of both groups were reconstructed by an iterative reconstruction algorithm. For objective evaluation of the image quality, image noise, vessel density, signal to noise ratio (SNR), and contrast to noise ratio (CNR) were measured. Two blinded readers then subjectively graded the image quality using a four-point scale (1: nondiagnostic to 4: excellent). Radiation exposure was also measured. Although the study group tended to show higher image noise (14.1 ± 3.6 vs. 9.3 ± 2.2 HU, P = 0.111) and higher vessel density (665.5 ± 161 vs. 498 ± 143 HU, P = 0.430) than the control group, the differences were not significant. There was no significant difference between the two groups for SNR (52.5 ± 19.2 vs. 60.6 ± 21.8, P = 0.729), CNR (57.0 ± 19.8 vs. 67.8 ± 23.3, P = 0.531), or subjective image quality scores (3.47 ± 0.55 vs. 3.59 ± 0.56, P = 0.960). However, radiation exposure was significantly reduced by 42 % in the study group (1.9 ± 0.8 vs. 3.6 ± 0.4 mSv, P = 0.003). Optimal tube voltage selection with the guidance of an automatic exposure control system in 320-ADCT coronary angiography allows substantial radiation reduction without significant impairment of image quality, compared to the results obtained using a BMI-based protocol.
Subtraction coronary CT angiography using second-generation 320-detector row CTYoshioka, Kunihiro; Tanaka, Ryoichi; Muranaka, Kenta; Sasaki, Tadashi; Ueda, Takanori; Chiba, Takuya; Takeda, Kouta; Sugawara, Tsuyoshi
doi: 10.1007/s10554-015-0630-1pmid: 25721727
The purpose of this study was to explore the feasibility of subtraction coronary computed tomography angiography (CCTA) by second-generation 320-detector row CT in patients with severe coronary artery calcification using invasive coronary angiography (ICA) as the gold standard. This study was approved by the institutional board, and all subjects provided written consent. Twenty patients with calcium scores of >400 underwent conventional CCTA and subtraction CCTA followed by ICA. A total of 82 segments were evaluated for image quality using a 4-point scale and the presence of significant (>50 %) luminal stenosis by two independent readers. The average image quality was 2.3 ± 0.8 with conventional CCTA and 3.2 ± 0.6 with subtraction CCTA (P < 0.001). The percentage of segments with non-diagnostic image quality was 43.9 % on conventional CCTA versus 8.5 % on subtraction CCTA (P = 0.004). The segment-based diagnostic accuracy for detecting significant stenosis according to ICA revealed an area under the receiver operating characteristics curve of 0.824 (95 % confidence interval [CI], 0.750–0.899) for conventional CCTA and 0.936 (95 % CI 0.889–0.936) for subtraction CCTA (P = 0.001). The sensitivity, specificity, positive predictive value, and negative predictive value for conventional CCTA were 88.2, 62.5, 62.5, and 88.2 %, respectively, and for subtraction CCTA they were 94.1, 85.4, 82.1, and 95.3 %, respectively. As compared to conventional, subtraction CCTA using a second-generation 320-detector row CT showed improvement in diagnostic accuracy at segment base analysis in patients with severe calcifications.
Coronary artery vasculitis: assessment with cardiac multi-detector computed tomographyJeon, Chang; Kim, Yeo; Chun, Eun; Kim, Jeong; Yong, Hwan; Doo, Kyung; Choi, Sang
doi: 10.1007/s10554-015-0652-8pmid: 25841665
Coronary artery vasculitis is rare and comprises an array of inflammatory diseases. It often results in severe and life-threatening complications, including coronary artery aneurysm, coronary artery stenosis, intraluminal thrombosis, and microcirculation abnormalities. These may occur at a young age and are often silent in the early phases. Invasive coronary angiography is the gold standard for diagnosing coronary artery disease (CAD); however, multi-detector computed tomography (MDCT) is now widely regarded as a powerful non-invasive tool for the detection of CAD. It is important for clinicians to recognize the various CT findings associated with coronary artery vasculitis in order to promote accurate diagnosis and proper patient management. The purpose of this article is to present an overview of the conditions associated with coronary artery vasculitis, with an emphasis on etiology and cardiac MDCT diagnosis of CAD. Cardiac MDCT is clinically useful and can provide information for the accurate diagnosis and treatment of coronary vasculitis.
Coronary CT findings of coronary to bronchial arterial communication in chronic pulmonary diseaseByun, Sung; Park, Jae; Kim, Jeong; Sung, Yon; Kim, Yoon; Kim, Eun; Park, Eun
doi: 10.1007/s10554-015-0647-5pmid: 25802014
To describe the coronary CT findings of coronary-to-bronchial artery communication (CBAC) in chronic pulmonary disease. Coronary CT was performed in 15 patients with chronic pulmonary disease using 64-channel or greater multidetector CT. Among those patients, one or two CBACs were identified. A retrospective analysis of the CT findings was done to determine the originating artery, arterial course of the communications and other associated results. The main underlying pulmonary disease was bronchiectasis (n = 12). The origin of the CBAC was from the left atrial (n = 7) or sinoatrial (SA) nodal (n = 3) branch of the left circumflex artery in nine patients and the SA nodal branch of the right coronary artery in six patients. The CBAC was connected to the left bronchial artery in 11 patients and the right bronchial artery in five patients. The course of the CBAC passed through the interpulmonary venous bare area between reflections of the serous pericardium of the transverse and oblique sinuses in 13 patients. In three patients, it passed through the perivascular space around the left upper or lower pulmonary vein. In one patient, there were two communications—one through the interpulmonary venous bare area and the other through the perivascular space around the left lower pulmonary vein. There was no significant coronary arterial stenosis except in two patients. Bronchial arterial hypertrophy was found in all 15 patients. Detailed analysis of coronary CT can be a helpful guide for hemodynamic significance and clinical management including embolotherapy for CBAC in patients of chronic pulmonary disease with hemoptysis.
Integrated cardiac magnetic resonance imaging with coronary magnetic resonance angiography, stress-perfusion, and delayed-enhancement imaging for the detection of occult coronary artery disease in asymptomatic individualsSong, Kyoung; Kim, Sung; Choe, Yeon Hyeon; Jung, Wooin; Lee, Sang-Chol; Chang, Sung-A; Choi, Yoon; Sung, Jidong
doi: 10.1007/s10554-015-0665-3pmid: 25916321
To evaluate the feasibility of using coronary magnetic resonance angiography (CMRA) with stress-perfusion and delayed-enhancement MRI as a screening tool for the detection of coronary artery disease (CAD) in asymptomatic subjects. Three hundred and forty-one self-referred asymptomatic subjects were enrolled in this study. Cardiac MR imaging was performed using a 1.5-T scanner with a 32-channel cardiac coil. Coronary artery stenosis, regional wall motion abnormalities, myocardial perfusion abnormalities, and delayed myocardial enhancement were analyzed. The occurrence of new chest pain and cardiac events was assessed in 332 subjects (97.3 %) over an average 29 ± 6 months (range, 18–39 months) follow-up period. A total of 3296 (82.4 %) of 4000 coronary artery segments examined exhibited diagnostic image quality on combined whole-heart and volume-targeted CMRA. Combined MRI detected significant CADs in 13 (3.8 %) of 341 subjects. Among these, 11 subjects (84.6 %) had both coronary artery stenosis (≥50 % by diameter) on CMRA and stress-perfusion defects in corresponding areas. Five of the 13 subjects showed evidence of old myocardial infarctions on delayed-enhancement MRI. Three subjects (0.9 %) underwent percutaneous coronary intervention after CAD was detected on cardiac MRI. There were no cardiac events during the follow-up period in subjects who complied with follow-up. Normal stress-perfusion and delayed-enhancement MRI lead to excellent outcomes when used to predict future cardiac events in asymptomatic subjects. Coronary MRA correlates well with stress-perfusion MRI for detecting significant CAD and helps exclude CAD in asymptomatic individuals.