Iron metabolism parameters in patients with chronic heart failure and reduced left ventricular ejection fraction depending on basic demographic, clinical and instrumental characteristics

Abstract

The aim – to study the iron metabolism parameters in patients with chronic heart failure (CHF) and reduced left ventricular ejection fraction (rLVEF) depending on main clinical characteristics of patients obtained during the instrumental study.
Material and methods. During period from January 2016 till February 2018, 134 stable patients with CHF (113 (84.3  %) of men and 21 (15.7 %) of women), 18–75 years old, NYHA class II–IV, with left ventricular ejection fraction
< 40 % were screened. Patients were included at a clinical compensation phase. Quality of life was assessed by the Minnesota living with heart failure questionnaire (MLHFQ), physical activity was estimated by the Duke University index, functional status – by assessing the 6-minute walking test (6MWT) and a standardized lower limb extension test.
Results and discussion. Iron deficiency was found in 83 (62 %) of 134 patients with CHF and rLVEF. There were no significant differences of iron metabolism in regard to CHF etiology and most co-morbidities. The presence of anemia was associated with lower ferritin, transferrin saturation (TSAT) and serum iron levels, and the presence of renal dysfunction – with the latter two. Patients in NYHA III–IV class had significantly lower TSAT and serum iron levels. The ferritin level was significantly higher only in group of patients with better muscular endurance, while TSAT and serum iron levels were also significantly higher in patients with greater 6-minutes walking distance, better hip muscles endurance, greater physical activity index and fewer scores by the Minnesota quality of life scale. Ferritin has shown a significant correlation with serum iron levels and hemoglobin. TSAT level correlated with a serum iron level, hemoglobin, limb muscles endurance, 6-minute walking test result, physical activity index and MLHFQ score.
Conclusions. Iron deficiency has been revealed in 62 % of patients with CHF and rLVEF. The plasma ferritin level is lower in patients with anemia and with worse muscle endurance. TSAT and serum iron levels are lower in patients with NYHA III–IV class, anemia, renal dysfunction, worse physical tolerance indicators and poorer quality of life. Both ferritin and TSAT demonstrate a relation to hemoglobin and iron plasma level, additionally TSAT – with physical activity index, 6-minutes walking test distance (6MWT), quadriceps femoris muscle endurance and MLHFQ quality of life.