NPPB and hereditary elliptocytosis: However, in the event of persistent HE > 1.5 × 109/L in patients not under treatment or in partial remission under treatment, regular heart examinations (troponin and BNP assays and TTE) are recommended (at frequent intervals in the first months following the onset of HE due to the high risk of organ complications during this period, and at longer intervals, e.g., annually thereafter) are recommended even in the absence of any symptoms due to the risk of pauci-symptomatic disease.