Importance of early diagnosis and treatment of heart failure across the spectrum of ejection fraction

Introduction Early diagnosis of heart failure (HF) is crucial in ensuring that optimal guideline-directed medical therapy (GDMT) is administered to reduce morbidity and mortality. Limited access to echocardiography could lead to late diagnosis for patients, for example during a HF hospitalisation (hHF).
Purpose The study aimed to compare the incidence and outcomes of inpatient versus outpatient diagnosis of HF across the ejection fraction (EF) spectrum.
Methods Electronic health records were linked to echocardiography data between 2016 to 2021. Diagnosis of incident HF was classified into inpatient (hHF) or outpatient (echocardiography reporting impaired left ventricular function or preserved EF with at least 2 continuous prescriptions of loop diuretics) and stratified by EF to define HF with reduced/mildly reduced/preserved EF (HFrEF/HFmrEF/HFpEF). A non-HF comparator group with normal LV function was also defined. The primary outcome was time to CV death or hHF.
Results 5251 individuals were identified, 1100 HFrEF, 650 HFmrEF, 1252 HFpEF, 1295 HF with unknown EF, and 954 non-HF comparators. Median duration of follow-up was 2.4 years. CV death or hHF were observed in 605 individuals (55%) with HFrEF, 237 (36%) with HFmrEF, 333 (27%) with HFpEF, 98 (10%) of non-HF comparators, and 647 (50%) with HF but unknown EF. Compared to non-HF individuals, HF patients had significantly worse outcome (hazard ratio [HR] adjusted for age and sex – HFrEF: 8.22 [95% CI: 6.64 – 10.18], p < 0.001; HFmrEF: 4.40 [3.47 – 5.58], p < 0.001; HFpEF: 2.89 [2.31 – 3.62], p < 0.001; HF with unknown EF: 8.22 [6.64 – 10.18], p < 0.001). Of the 4297 HF patients, 2318 (54%) were diagnosed as inpatients, an increase from 42% in 2016 to 62% in 2021. Those diagnosed as inpatients had significantly worse outcome than those diagnosed as outpatients (adjusted HR: 1.83 [1.66 – 2.01], p < 0.001). This difference was driven by those with HFpEF (adjusted HR: 2.31 [1.80 – 2.96], p < 0.001), but was not seen in HFrEF (1.05 [0.89 – 1.23], p = 0.554) or HFmrEF (0.97 [0.73 – 1.28], p = 0.811). For HFrEF patients first diagnosed as inpatients, those discharged on GDMT had a reduced incidence of the primary outcome: adjusted HR compared to those discharged on no GDMT drugs - monotherapy 0.77 [0.51 - 1.16], p = 0.205; dual-therapy 0.57 [0.37 – 0.88], p = 0.011; and triple therapy 0.54 [0.33 – 0.90], p = 0.017.
Conclusion Individuals whose first presentation of HF was a HF hospitalisation had a significantly worse outcome than those who were diagnosed in the community. These real-world data also demonstrate the benefit of early optimisation of GDMT during a hHF. Our results highlight the importance of improving diagnostic pathways to allow for earlier identification and treatment of HF across the ejection fraction spectrum.