Enhanced prognostic stratification of CAD patients with low ejection fraction by stress-rest Tc99m tetrofosmin gated-spect.
OBJECTIVE
This study was performed to assess whether post-stress and rest functional parameters, as measured by gated-SPECT, provide additional predictive value for long-term prognosis, over clinical and perfusion data in patients (pts.) with low left ventricular ejection fraction (LVEF).


METHODS
647 consecutive pts. underwent stress/rest gated-SPECT, and 497 were followed for a mean period of 516 +/- 264 days. Segmental perfusion and motion/thickening (post-stress and rest) were analysed visually, while EF and LV volumes were calculated using an automatic algorithm (QGS). The post-stress and rest ratio were determined for both end-diastolic (EDV) and end-systolic volume (ESV), while the post-stress LVEF change was calculated subtracting rest-EF from stress-EF.


RESULTS
84/497 pts. showed rest EF < 40%, and 15/84 (18%) experienced a cardiac event (3 cardiac deaths, 1 infarction, 3 hospitalized angina and 9 late revascularizations). The perfusion and functional parameters were not significantly more compromised in pts. with cardiac events compared with pts. without events. Post-stress ESV was the only index significantly higher in pts. with low EF and events compared with pts. with low EF without events (150 +/- 72 ml vs. 123 +/- 53 ml, P = 0.02). Univariate Cox analysis of clinical, perfusion and functional data showed that the best predictor of cardiac events was stress-ESV (score 6.5, P = 0.01), followed by rest-ESV, rest-EDV, stress-EDV and stress-LVEF. Multivariate analysis demonstrated that the addition of stress-ESV to stress-EF, yielded a significant increase in the global chi2 in the prediction of hard events (cardiac death/infarction) (score 4.634, P = 0.03).


CONCLUSIONS
In patients with depressed LVEF, stress-ESV was the only independent predictor of long-term outcome.
Bestetti
Alberto
A
Cattedra di Medicina Nucleare, Università degli Studi di Milano c/o Ospedale S.Paolo-Milano, Italy. alberto.bestetti@unimi.it
Triulzi
Antonio
A
Di Leo
Claudio
C
Tagliabue
Luca
L
Strinchini
Aldo
A
Bax
Jeroen
J
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002302:Cardiac Output / Q000502:physiology; D017023:Coronary Angiography; D003324:Coronary Artery Disease / Q000000981:diagnostic imaging / Q000503:physiopathology*; D005080:Exercise Test; D005500:Follow-Up Studies; D015637:Gated Blood-Pool Imaging / Q000379:methods*; D006352:Heart Ventricles / Q000000981:diagnostic imaging / Q000503:physiopathology*; D006801:Humans; D018810:Magnetic Resonance Angiography / Q000379:methods; D008875:Middle Aged; D009943:Organophosphorus Compounds; D015609:Organotechnetium Compounds; D011379:Prognosis; D013318:Stroke Volume / Q000502:physiology*; D016019:Survival Analysis
D009943:Organophosphorus Compounds; D015609:Organotechnetium Compounds; C078700:technetium tc-99m tetrofosmin