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

Table 3 Comparison of various methods to evaluate cardiac iron overload in thalassemia patients

Method	Advantages	Disadvantages
Serum ferritin	Easy and available	Poor predictor of iron overload[85,86]
	Inexpensive	Nonspecific for cardiac iron
		Altered by many conditions[14]
Echocardiogram	Easy and available	Late indicator of cardiac involvement[21,23]
	Inexpensive
Liver biopsy	Total body iron estimation[32]	Invasive
		No correlation with myocardial iron deposition[33]
Myocardial biopsy		Invasive No correlation with cardiac iron status and function[34]
ECG	Easy and available	Ineffective screening parameter for cardiac iron overload[25,31]
	Inexpensive
SQUID	Standardized noninvasive index for liver iron[36]	Lack of availability, technical demands, and reproducibility
		Costly
		Application for the study of heart iron pending
NTBI	Direct parameter of freeform iron resulting in	Limited availability
	peroxidative damage[87]	No generally accepted method[48], and poor correlation
		between methods[49]
CMR T2*	Method of choice for the assessment of tissue iron deposition in last decade[51]	Costly
	Noninvasive measurement of cardiac iron deposition[50]
	Available
	High sensitivity and reproducible[50]
	Correlation with clinical outcome[16,17,56,62,63]

ECG: Electrocardiogram; SQUID: Superconducting quantum interference device; NTBI: Non-transferrin-bound iron; CMR T2*: Cardiac magnetic resonance T2*.