Rest and low-dose dobutamine Tc-99m-mibi gated-SPECT for early prediction of left ventricular remodeling after a first reperfused myocardial infarction

Left ventricular (LV) remodeling after myocardial infarction (MI) occurs frequently despite successful percutaneaous coronary intervention (PCI) but cannot be predicted by simple clinical parameters. This prospective study tested the value of rest and low-dose dobutamine (LDD) Tc-99m-mibi gated-SPECT for early prediction of LV remodeling in patients treated by PCI in the acute phase of a first MI. Infarct size, infarct severity, regional wall motion abnormality (RWMA), and wall thickening score (WTs) were assessed at rest and on LDD by SPECT 6 +/- A 2 days after MI in 40 patients. LV remodeling was defined as 20% increase at 6 months in LV end-diastolic volume assessed by MRI. Infarct severity at rest showed the best predictive values for left remodeling (PPV: 86%, NPV: 88%, accuracy: 88%; AUC: 0.750). Functional parameters at neither rest nor LDD study further improved predictive values of the SPECT imaging. Infarct severity assessed by Tc-99m-sestamibi gated-SPECT performed in the subacute phase of a first STEMI predicts LV remodeling with high accuracy without incremental value nor of functional parameters nor of LDD. Therefore, our results suggest that LDD should not be used in this setting.