The optimal dose of diuretics and nitrates for acute heart failure treatment remains uncertain. This study aimed to assess the association between intravenous nitrates and loop diuretics doses within the initial 4 h of emergency department presentation and the number of days alive and out of hospital (NDAOH) through 30 days. This was an ancillary study of the ELISABETH stepped-wedge cluster randomized trial that included 502 acute heart failure patients 75 years or older in 15 French emergency departments. The primary endpoint was the NDAOH at 30 days. The total dose of intravenous nitrates and loop diuretics administered in the initial 4 h were each categorized into three classes: 'no nitrate', '> 0-16', and '> 16 mg' for nitrates and '< 60', '60', and '> 60 mg' for diuretics. Secondary endpoints included 30-day mortality, 30-day hospital readmission, and hospital length of stay in patients alive at 30 days. Generalized linear mixed models were used to examine associations with the endpoints. Of 502 patients, the median age was 87 years, with 59% women. The median administered dose within the initial 4 h was 16 mg (5.0; 40.0) for nitrates and 40 mg (40.0; 80.0) for diuretics. The median NDAOH at 30 days was 19 (0.0-24.0). The adjusted ratios of the NDAOH were 0.88 [95% confidence interval (CI): 0.63-1.23] and 0.76 (95% CI: 0.58-1.00) for patients that received 60 and > 60 mg, respectively, compared with patients that received 40 mg or less of diuretics. Compared with patients who did not receive nitrates, the adjusted ratios of the NDAOH were 1.17 (95% CI: 0.82-1.67) and 1.45 (95% CI: 0.90-2.33) for patients who received 1-16 and > 16 mg, respectively. There was no significant association with any of the secondary endpoints. In this ancillary analysis, there was no significant association between different doses of diuretics and nitrates with the NDAOH at 30 days. Point estimates and CIs may suggest that the optimal doses are less than 60 mg of diuretics, and more than 16 mg of nitrates in the first 4 h.