Early detection of cardiac involvement in thalassemia: From bench to bedside perspective

Table 4 Summary of heart rate variability findings from both clinical and basic studies in thalassemia

Population/size	Type of study	Findings	Ref.
34 TM patients and 20 healthy subjects	Prospective	Significantly depressed both time and frequency domain HRV parameters in TM patients	Rutjanaprom et al[20]
32 TM patients and 46 control subjects	Prospective	Significantly reduced all HRV parameters in TM patients	Kardelen et al[77]
19 TM patients and 19 healthy volunteers	Cross sectional	Significantly lower both time and frequency domain HRV parameters in the TM group	Franzoni et al[75]
100 TM patients and 60 healthy controls	Cross sectional	Lower SDNN in TM with ectopia while markedly increased LF/HF ratio in this group.	Oztarhan et al[88]
48 Thalassemia patients and 45 healthy subjects	Cross sectional	Significantly reduced time domain parameters in the thalssemia group	Gurses et al[89]
9 TM patients and 9 healthy subjects	Cross sectional	Significantly lower LF/HF ratio during tilt in TM patients than in control subjects	Veglio et al[90]
21 TM patients and 15 healthy subjects	Cross sectional	Significantly lower in all HRV parameters in TM group than in control group	Ma et al[91]
13 wildtype, 13 HbE/β thalassemia and 13 muβ+/− mice	Cross sectional	Depressed all HRV parameters in the heterozygous βglobin knockout mice (muβ+/−)	Incharoen et al[92]
810 wildtype and 810 heterozygous betaknockout mice	Prospective	Higher LF ⁄ HF ratio in thalassemic mice than those in the wild type	Kumfu et al[82]
12 wildtype and 12 heterozygous betaknockout mice	Prospective	Depressed HRV in betathalassemic mice compared to wild type	Thephinlap et al[93]

TM: Thalassemia major; HRV: Heart rate variability; SDNN: Standard deviation of all NN intervals; LF: Low frequency power; HF: High frequency power.