Validation of a Novel Method for Cardiac Output Estimation by CT Coronary Angiography

作     者：Hetal H. Mehta Brian G. Choi Reza Sanai Raman S. Dusaj Amr Mohsen Chunlei Liang Jannet F. Lewis Robert K. Zeman 

作者机构：Department of Mechanical and Aerospace Engineering The George Washington University Washington DC USA Department of Medicine The George Washington University Washington DC USA Department of Radiology The George Washington University Washington DC USA 

出 版 物：《Advances in Computed Tomography》 (计算机断层扫描（英文）)

年 卷 期：2012年第1卷第2期

页      面：11-16页

学科分类：1002[医学-临床医学] 100214[医学-肿瘤学] 10[医学] 

主　　题：Cardiac Output Coronary CT Angiography Hemodynamics Prospective Triggering Validation 

摘      要：Background: Cardiac output can be estimated during retrospectively gated CT coronary angiography by anatomically determining left ventricular volumes;prospective triggering to minimize radiation precludes this methodology. We propose an alternative method for cardiac output estimation based on preclinical models suggesting that cardiac output may be inversely related to contrast washout from the aortic root during timing bolus scanning, as measured by peak aortic root contrast attenuation. Methods: 34 patients had CT coronary angiography timing bolus performed with 20 ml iodixanol at 5.5 ml/s followed by 20 ml normal saline at 5.5 ml/s through an 18-Ga antecubital catheter. Peak aortic root contrast attenuation was correlated to cardiac output calculated by echocardiography using heart rate stroke volume from biplane Simpson’s ***: Mean age was 58 ± 13 years;body surface area, 2.0 ± 0.5 m2. 53% were women. Stroke volume, cardiac output and cardiac index were 67 ± 19 ml, 4.5 ± 1.6 L/min, and 2.2 ± 0.7 L/min/m2, respectively. Peak aortic root contrast attenuation was 207 ± 46 HU and correlated to cardiac output and cardiac index with r = –0.64, p Conclusion: This novel method for cardiac output estimation by CTCA appears feasible. The CT physiologic parameters using the timing test-bolus data moderately correlated with echocardiographic assessment of cardiac output. The calculation of cardiac output adds important hemodynamic data to anatomic information provided by CTCA, and further development of this method may preserve assessment of left ventricular performance in prospective triggering.