Markiewicz W, Sechtem U, Kirby R, Derugin N, Caputo G C, Higgins C B
J Am Coll Cardiol. 1987 Jul;10(1):170-7. doi: 10.1016/s0735-1097(87)80176-6.
Nuclear magnetic resonance (NMR) imaging is a new, noninvasive approach for imaging the cardiovascular system. Being a three-dimensional technique, NMR imaging has the capability of measuring volumes without the need for assumptions regarding ventricular geometry. In this study, the technique was validated in 19 excised dog hearts, filled with silicone-rubber, imaged using a multislice spin-echo sequence. The volume of the cavity in each slice was calculated from the number of pixels outlined for each slice multiplied by the pixel volume. Ventricular volumes measured by NMR imaging were highly correlated with cast volumes measured by water displacement: right ventricle (RV):RVNMR = 1.05 RVcast - 1.62; r = 0.99, SEE = 0.96 ml; left ventricle (LV):LVNMR = 0.98 LVcast + 0.35, r = 0.98, SEE = 1.48 ml. After validation in casts, NMR imaging volumes were measured in eight living dogs using a multiphasic gated technique to obtain images at 5, 105, 205, 305 and 405 ms after the QRS complex. Cardiac output (CO) and stroke volume (SV) measured by NMR imaging were significantly correlated with thermodilution (TD) measurements (CONMR = 0.63 COTD + 0.51 liters/min; r = 0.78, SEE = 0.57 liters/min; SVNMR = 0.67 SVTD + 1.95 ml; SEE = 5.58 ml). Right and left stroke volumes were closely related (LVSVNMR = 0.9 RVSVNMR + 1.75; r = 0.94, SEE = 4.32 ml), with the slope and intercept of the regression line showing no difference from 1 and 0, respectively. However, volumes determined by NMR imaging underestimated the thermodilution measurements, presumably reflecting the inability to obtain a true systolic image with the present sampling rate.(ABSTRACT TRUNCATED AT 250 WORDS)
核磁共振（NMR）成像技术是一种用于心血管系统成像的新型非侵入性方法。作为一种三维技术，NMR成像能够测量容积，而无需对心室几何形状做任何假设。在本研究中，该技术在19个填充有硅橡胶的离体犬心脏中得到验证，采用多层自旋回波序列进行成像。每个切片中的腔室容积通过将每个切片勾勒出的像素数量乘以像素容积来计算。通过NMR成像测量的心室容积与通过水置换法测量的铸型容积高度相关：右心室（RV）：RVNMR = 1.05 RVcast - 1.62；r = 0.99，标准误（SEE）= 0.96 ml；左心室（LV）：LVNMR = 0.98 LVcast + 0.35，r = 0.98，SEE = 1.48 ml。在铸型中验证后，对8只活体犬使用多期门控技术在QRS波群后5、105、205、305和405毫秒获取图像，测量NMR成像容积。通过NMR成像测量的心输出量（CO）和每搏输出量（SV）与热稀释法（TD）测量结果显著相关（CONMR = 0.63 COTD + 0.51升/分钟；r = 0.78，SEE = 0.57升/分钟；SVNMR = 0.67 SVTD + 1.95 ml；SEE = 5.58 ml）。左右每搏输出量密切相关（LVSVNMR = 0.9 RVSVNMR + 1.75；r = 0.94，SEE = 4.32 ml），回归线的斜率和截距分别与1和0无差异。然而，通过NMR成像确定的容积低估了热稀释法测量结果，这可能反映了以当前采样率无法获得真正的收缩期图像。（摘要截选至250词）
