Low iron storage may increase arrhythmogenic susceptibility through elevated fragmented QRS (fQRS) presence and increased Tpeak-Tend (Tp-e) interval, Tp-e/QT, and Tp-e/QTc ratios in healthy women of childbearing age, according to a study published in the Journal of Electrocardiology.
In this study, 201 women (average age, 37±9 years; range, 18-50 years) with no history of chronic and cardiac disease or anemia were enrolled. The participants were categorized into 3 groups based on ferritin levels. The fQRS, Tp-e interval, Tp-e/QT, and Tp-e/QTc ratios were calculated manually, and 12-lead electrocardiograms were obtained from each patient.
Group 1 (ferritin <15 ng/mL) included 79 patients (39.3%), group 2 (ferritin 15-30 ng/mL) included 64 patients (31.8%), and group 3 (ferritin ≥30 ng/mL) included 58 (28.9%) patients.
The Tp-e interval was found to be elevated in group 1 compared with groups 2 and 3 (P <.001 for both). A similar relationship was observed for Tp-e/QT, Tp-e/QTc, and fQRS (P <.001 for all).
Moderate, negative correlations were identified between Tp-e, Tp-e/QT, Tp-e/QTc, and fQRS and ferritin value (r = −0.519; P =.001; r = −0.485; P = .001; r = −0.540; P =.001; and r = −0.345; P =.001, respectively).
”In this study, the primary purpose of the preference for women of childbearing age was that they constitute the group of patients with a higher incidence of low iron storage. Low iron storage is more common than iron deficiency anemia, and [women] are affected more than [men],” noted the study authors.
Study limitations include its retrospective design, the lack of long-term follow-up of arrhythmic complications and electrocardiographic changes after iron replacement therapy.
“The fQRS and Tp-e interval, which were associated with many cardiac-poor outcomes and arrhythmogenic predispositions, will help clinicians in more closely monitoring of ferritin-deficient healthy women and, if necessary, in deciding on replacement therapy in these groups of patients,” concluded the study authors.
Yilmaz E, Aydin E. The effect of low iron storage without anaemia on electrocardiography. J Electrocardiol. 2020;64:76-79.