Heart rate recovery as a novel test for predicting cardiac involvement in beta-thalassemia major
Acta Cardiologica Sinica, cilt.33, sa.4, ss.410-419, 2017 (SCI-Expanded, Scopus)
- Yayın Türü: Makale / Tam Makale
- Cilt numarası: 33 Sayı: 4
- Basım Tarihi: 2017
- Doi Numarası: 10.6515/acs20161104a
- Dergi Adı: Acta Cardiologica Sinica
- Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus
- Sayfa Sayıları: ss.410-419
- Anahtar Kelimeler: Beta thalassemia major, Exercise stress test, Heart rate recovery, Magnetic resonance imaging
- Sağlık Bilimleri Üniversitesi Adresli: Evet
Özet
Background: Abnormal heart rate recovery (HRR) is predictive of cardiac mortality. Autonomic abnormalities in beta-thalassemia major (TM) patients have been reported in previous studies. However, the importance of low HRR in exercise stress test in TM patients has not yet been ascertained. Therefore, this study will be the first of its kind in the literature. Methods: Exercise stress test was performed on 56 TM patients who were being treated at the Thalassemia Center of our hospital, alongwith 46 non-TM iron deficiency anemia (IDA) patients as a control group. Values for HHR were recorded at 1, 2, 3, 4 and 5 min, and HRR was calculated by the difference of heart rate at peak exercise and at a specific time interval following the onset of recovery. Results: All HRR values were found to be lower in TM patients compared to those in the IDA group. Exercise capacity [metabolic equivalents (METs)] was also found to be low in these patients (p < 0.001) as well. Total exercise time was significantly lower in the TMgroup compared to the IDA group (8.40 ± 1.7min vs. 11.17 ± 1.51 min, p < 0.001). Exercise capacity (METs) was also lower in the TMgroup compared to the IDA group. Mean T2* value was 28.3 ± 13.7ms in TM patients on magnetic resonance imaging (MRI). In addition, there are 18 TMpatients with T2* value was < 20ms. Conclusions: This study found that TM was independently associated with low HRR. Such a condition is an indicator of autonomic dysfunction inTMpatients, since abnormal HRR is related to impaired autonomic response. In addition, impaired HRR may be a marker of early cardiac involvement in patients, whose T2* value is high on MRI. Modifying HRR with a cardiac rehabilitation program in TM patients with impaired HRR is a field open for further investigation.