Low impact of cardiovascular adverse events on anagrelide treatment discontinuation in a cohort of 232 patients with essential thrombocythemia.

This retrospective study of the thrombocythemia Italian registry (RIT) documented that 71 (30.6%) out of 232 ET patients experienced 88 cardiovascular adverse events (CV-AEs) during anagrelide treatment (522 pt-y). The rate of CV-AEs was: 24.1% for palpitations, 4.3% for angina, 3.5% for arterial hypertension, 3.0% for congestive heart failure, 1.8% for arrhythmia, 0.9% for AMI, 0.4% for pericardial effusion. CV-AEs led to treatment discontinuation in nine (3.9%) patients, while in the remaining cases they were managed by pharmacological intervention and/or patient life style improvement. CV-AEs had no relationship with patient characteristics (including older age). A significant relationship was found only with a higher anagrelide induction dose. In the absence of any agreed protocol, a cardiovascular instrumental evaluation (CV-IE) was performed in 102 (44%) patients before commencement of anagrelide (with higher rate after the anagrelide/Xagrid EMA approval of 2004), and in 84 (36%) patients during treatment. Patients with and without CV-IEs, who resulted completely balanced for all their characteristics, did not significantly differ in the occurrence of CV-AEs. In conclusion, this study on ET patients treated with anagrelide shows that CV-AEs, equally distributed in younger and older subjects, were mostly mild and easily manageable, allowing safe treatment continuation in the majority of cases. Moreover, routinely performing a CV-IE did not appear to anticipate the occurrence of CV-AEs.