Analysis of mortality in patients with heart failure after de-compen-sation during long-term follow-up in specialized medical care and in real clinical practice

Abstract

Background Mortality from chronic heart failure (CHF) remains high and entails serious demographic losses worldwide. The most vulnerable group is patients after acute decompensated HF (ADHF) who have a high risk of unfavorable outcome.Aim To analyze risks of all-cause death (ACD), cardiovascular death (CVD), and death from recurrent ADHF in CHF patients during two years following ADHF in long-term follow-up with specialized medical care and in real-life clinical practice.Material and methods The study successively included 942 CHF patients after ADHF. 510 patients continued out-patient treatment in a specialized CHF treatment center (CHFTC) (group 1) and 432 patients refused of the management in the CHFTC and were managed in out-patient clinics at the place of patient's residence (group 2). Causes of death were determined based on inpatient hospital records, postmortem reports, or outpatient medical records. Cases of ACD, CVD, death from ADHF, and a composite index (CVD and death from ADHF) were analyzed. Statistical analysis was performed with the software package Statistica 7.0 for Windows, SPSS, and statistical package R.Results Patients of group 2 were older, more frequently had functional class (FC) III CHF and less frequently FC I CHF compared to group 1. Women and patients with preserved left ventricular ejection fraction (LV EF) prevailed in both groups. Results of the Cox proportional hazards model for ACD, CVD, death from ADHF, and the composite mortality index showed that belonging to group 2 was an independent predictor for increased risk of death (р<0.001). An increase in CCS score by 1 also increased the risk of death (р<0.001). Baseline CHF FC and LV EF did not influence the mortality in any model. Female gender and a higher value of 6-min walk test (6MW) independently decreased the risk of all outcomes except for CVD. An increase in systolic BP by 10 mm Hg reduced risk of all fatal outcomes. At two years of follow-up in groups 2 and 1, ACD was 29.9 % and 10.2 %, (OR, 3.7; 95 % CI: 2.6-5.3; p <0.001), CVD was 10.4 % and 1.9 % (OR, 5.9; 95 % CI: 2.8-12.4; p<0.001), death from ADHF was 18.1 % and 6.0 % (OR, 3.5; 95 % CI: 2.2-5.5; p<0.001), and the composite mortality index was 25.2 % and 7.7 % (OR, 4.1; 95 % CI: 2.7-6.1; р<0.001). Analysis of all outcomes by follow-up period (3 and 6 months and 1 and 2 years) showed that the difference between groups 2 and 1 in risks of any fatal outcome was maximal during the first 6 months.Conclusion The follow-up in the system of specialized medical care reduces risks of ACD, CVD, and death from ADHF. The first 6 months following discharge from the hospital was a vulnerability period for patients after ADHF. The CCS score impaired the prognosis whereas baseline LV EF and CHF FC did not influence the long-term prognosis after ADHF. Protective factors included female gender and higher values of 6MW and systolic BP.