Echocardiographic validation of gated SPECT ventricular function measurements

Citation
K. Nichols et al., Echocardiographic validation of gated SPECT ventricular function measurements, J NUCL MED, 41(8), 2000, pp. 1308-1314
Citations number
40
Categorie Soggetti
Radiology ,Nuclear Medicine & Imaging","Medical Research Diagnosis & Treatment
Journal title
JOURNAL OF NUCLEAR MEDICINE
ISSN journal
01615505 → ACNP
Volume
41
Issue
8
Year of publication
2000
Pages
1308 - 1314
Database
ISI
SICI code
0161-5505(200008)41:8<1308:EVOGSV>2.0.ZU;2-J
Abstract
Left ventricular (LV) volumes are valuable prognostic indicators in the man agement of coronary artery disease and traditionally have been obtained by x-ray contrast angiography or echocardiography. There now are several scint igraphic methods to compute volumes that are based on different LV modeling assumptions. Both the reasons that calculations from different nuclear tec hniques can disagree with one another and the relationship of these values to the more conventional echocardiographic measurements must be investigate d thoroughly for calculations to be interpretable for individual patients. Methods: Echocardiographic volumes were determined in 33 retrospective subj ects with coronary artery disease (mean age, 61 +/- 12 y; 42% men; 70% with abnormal perfusion and 58% with abnormal segmental wall motion) using the modified Simpson's rule technique applied to digitized apical 4-chamber and apical P-chamber views of 4 averaged heartbeats. These volumes were compar ed with those from 3 gated SPECT methods based on Simpson's rule LV modelin g similar to standard echocardiographic algorithms (SPECT EF from St. Luke' s-Roosevelt Hospital) (method 1), Gaussian myocardial count profile curve f itting (QGS from Cedars-Sinai Medical Center) (method 2), and an endocardia l model based on perfusion sampling and count-based thickening (Cardiac Too lbox from Emery University) (method 3). Results: By ANOVA, there were no si gnificant differences among ejection fractions (EFs), but there were for vo lumes. Paired t test analysis showed volumes from methods 2 and 3 to be sig nificantly larger than echocardiographic volumes and larger than those of m ethod 1. Linear regression analysis comparing gated SPECT and echocardiogra phic volumes showed a nearly identical strong correlation (r = 0.92; P < 0. 000001) for all 3 methods. Excellent correlation also was found among gated SPECT volumes from the 3 methods (r = 0.94), Bland-Altman analysis and t t ests showed that method I volumes (70 +/- 61 mt) were the same as for echoc ardiography (77 +/- 55 mL), but volumes were overestimated by method 2 (105 +/- 74 mt) and method 3 (127 +/- 92 mi), particularly for larger volumes. Pearson coefficients for EFs compared with echocardiography were r = 0.82, 0.75, and 0.72 for methods 1-3, respectively. EFs correlated strongly among the 3 gated SPECT methods (r = 0.86-0.92). The Fisher z test showed no dif ferences among these methods for any of the volume or EF linear correlation analyses. Conclusion: All gated SPECT parameters correlated well with echo cardiographic values. However, the gated SPECT method for which underlying assumptions most closely resembled those commonly used in echocardiography produced mean volume Values closest in agreement with echocardiographic mea surements.