Electrocardiographic evolution after Q-wave anterior myocardial infarction: correlations between QRS score and changes in left ventricular perfusion and function.

BACKGROUND: In the thrombolytic era, conflicting data have been reported on the usefulness of the QRS score in estimating the amount of left ventricular (LV) damage after acute myocardial infarction (MI). METHODS AND RESULTS: We correlated the QRS score with the extent of LV hypoperfusion and ejection fraction (EF) in 95 consecutive male patients with a first anterior Q-wave MI; the 6-month evolution of QRS score and changes in LV perfusion and function were also compared. The Selvester-Wagner QRS score was computed from the digitized 12-lead electrocardiogram, both at predischarge and 6 months later; at the same time, resting sestamibi first-pass ventriculography and single photon emission computed tomography imaging were performed. A reduction in QRS score occurred at 6 months (6.7 +/- 3.4 vs 7.8 +/- 2.9 at predischarge; P <.001); the perfusion defect extent also decreased (P <.01), and LV EF improved (P <.05). At predischarge, no correlation was found between QRS score and hypoperfusion extent or EF; in contrast, a weak correlation was observed 6 months later (r = 0.55; P <.001; and r = 0.48; P <.01, respectively). QRS score changes from predischarge to 6 months showed limited accuracy in predicting clinically meaningful changes of perfusion or EF (receiver operating characteristic area under the curve, 0.58 and 0.61, respectively). Thrombolytic therapy did not influence the relationship between QRS score and scintigraphic findings. CONCLUSIONS: In patients with recent anterior Q-wave MI, QRS scoring showed a weak, delayed correlation with the amount of LV damage, as estimated by radionuclide techniques. Spontaneous changes in QRS score from predischarge to 6 months seem to be of limited value in identifying patients with late improvement in LV perfusion and function

Evaluation of technetium-99m-sestamibi lung uptake: correlation with left ventricular function.

Lung uptake of 201Tl is a reliable marker of left ventricular dysfunction. The goal of our study was to establish whether the evaluation of lung-to-heart uptake ratios (LHR) with 99mTc-sestamibi imaging may provide valuable information. METHODS: We studied 72 male subjects with recent anterior myocardial infarction undergoing 99mTc-sestamibi first-pass ventriculography and SPECT perfusion imaging. A group of 46 gender-matched subjects with low pre-test likelihood of CAD and normal exercise and rest 99mTc-sestamibi perfusion images was used as a control. The lung-to-heart count ratios (LHR) were calculated on planar projections from the sets of SPECT images. RESULTS: Both groups were studied at rest and after a symptom-limited exercise tolerance test. In the control group a significant decrease in LHR was observed during stress (p < 0.001). The infarcted group showed significantly higher LHR values both at rest and at stress. Exercise and rest LHR values did not differ significantly. A positive correlation was observed between LHR values and left ventricular ejection fraction at rest and stress. CONCLUSION: LHR, measured by 99mTc-sestamibi imaging, gives clinically useful information. Both resting and postexercise values are correlated with ejection fraction and should predict left ventricular dysfunction