BACKGROUND: Our aim was to assess the distribution of primary (with no trigger) and secondary (with a decompensation trigger) heart failure events in a severe heart failure population and their association with two-year all-cause mortality in the Mitra.Fr study. METHODS: We included 304 patients with symptomatic heart failure, and severe mitral regurgitation and guideline directed medical therapy randomized to medical therapy alone or medical therapy with percutaneous mitral valve repair. According to the follow-up, we defined three categories of events: follow-up without any heart failure event, at least one decompensation starting with a primary heart failure decompensation or starting with a precipitated secondary heart failure event. The primary outcome was 2-years all-cause mortality. RESULTS: 179 patients (59 %) had at least one heart failure decompensation within 24-months of follow-up. 129 heart failure decompensations (72%) were a first primary heart failure and 50 (28%) were a first secondary decompensation. Finally, 30 patients had both types of decompensations but these were not taken into account for the comparison of primary and secondary decompensations. Primary decompensations were 3-times more frequent than secondary decompensations, but the mean number of heart failure decompensations was similar in the "Primary heart failure group" compared to the "Secondary heart failure group": (1.94±1.39 versus 1.80±1.07 respectively; p=0.480). Compared to patients without heart failure decompensation, patients with "Only primary decompensation" or with "Only secondary decompensation" had a significantly increased risk of death (HR=4.87, 95%CI [2.86, 8.32] and 2.68 95%CI [1.64, 4.37] respectively). All-cause mortality, was not significantly different between these two type of decompensations (HR=1.82, 95%CI [0.93, 3.58]; p=0.082), but each additional heart failure recurrence was associated with a significant increase in mortality risk (HR=1.27, 95%CI [1.08; 1.50]; p=0.005). CONCLUSIONS: In heart failure with reduced ejection fraction and severe secondary mitral regurgitation patients, primary heart failure decompensations were three-times more frequent compared to precipitated decompensations with a non-significant trend in increased risk of all-cause mortality. Our results fail to support the differentiation between primary and secondary decompensations as they seem to portend the same outcome impact.