We read with interest the work by Fertin et al, who reported the important finding that despite significant associations on univariate analyses, none of the biomarkers B-type natriuretic peptide (BNP), cardiac troponin I (TnI), and C-reactive protein at baseline (serial blood sampling from days 3 to 7) was retained as an independent predictor of left ventricular (LV) remodeling when the ejection fraction was entered into the multivariate model in Remodelage Ventriculaire 2 (REVE-2). In contrast, Hallén et al found that a single-point measurement of TnI 24 or 48 hours after primary angioplasty for those with ST-segment elevation myocardial infarctions in addition to the LV ejection fraction could provide prognostic information on LV remodeling from the results of FX06 in Ischemia and Reperfusion (FIRE). Actually, these results may all be correct, because the times of blood sampling at baseline in the 2 trials were different. However, there existed critical concerns regarding some patients in the gray zone that the 2 models the investigators provided could not explain clearly enough.

For example, Hallén et al’s study, most patients with initial ejection fractions <40% who experienced recovered LV ejection fractions (45%) at 3 months had overlapping TnI levels with those with mildly impaired LV systolic function (40% to 45%) and initially high levels of TnI (49.76 ng/ml <TnI <91 ng/ml). Besides, Fertin et al’s study, patients with BNP levels ≥95 pg/ml but TnI levels <0.05 ng/ml at 1 month had higher LV remodeling rates at 1 year than those with BNP levels <95 pg/ml but TnI levels ≥0.05 ng/ml. In our opinion, the rapid decrease in BNP within 1 month after primary angioplasty could be seen as a predictor for patients with initially significant LV dysfunction who recovered later.

As we know, myocardial stunning after myocardial infarction can persist for months. Patients with large myocardial ischemic areas may present with acute LV systolic dysfunction and advanced Killip classification, which are associated with higher BNP and TnI levels during myocardial infarction. Given that they received rapid coronary revascularization (ischemic time <3 hours), most viable myocardium would be saved and cardiac function returned to nearly normal, accompanied by the decrease in BNP. Therefore, we emphasize the prognostic value of the decrease in BNP <1 month after primary angioplasty, which may provide additional information regarding future LV remodeling rather than a single value of BNP or TnI for patients in this category.