From the Guidelines
Echocardiography can detect signs of iron overload in the heart, but it is not sensitive enough to directly detect iron deposits, and cardiac MRI with T2* imaging is the gold standard for assessing cardiac iron overload. According to the most recent study 1, echocardiography can reveal biventricular dilatation, restrictive cardiomyopathy, and ventricular diastolic dysfunction, which are indicative of iron overload cardiomyopathy. However, the study also notes that echocardiography has limitations in detecting early or mild iron deposition.
Some key points to consider when using echocardiography to detect iron overload in the heart include:
- Echocardiography can detect diastolic dysfunction, which can be an early sign of iron overload cardiomyopathy 2
- Tissue Doppler signals can be used to detect early signs of iron overload, such as decreased peak systolic and peak diastolic early filling tissue Doppler wave 2
- Cardiac MRI with T2* imaging is the gold standard for assessing cardiac iron overload, as it can quantify iron concentration more precisely 1
- Echocardiography is still valuable as an initial screening tool and for monitoring cardiac function in patients with suspected iron overload
It's also important to note that iron deposits in the heart can lead to serious complications, such as cardiomyopathy, heart failure, and arrhythmias, if left untreated. Treatment typically involves iron chelation therapy with medications like deferoxamine, deferiprone, or deferasirox to remove excess iron from the body.
In terms of clinical practice, the European Association for the Study of the Liver (EASL) recommends a structured patient interview, physical examination, and cardiac investigations, including echocardiography and/or cardiac MRI, to assess cardiac iron overload in patients with haemochromatosis 1. Cardiologist consultation is recommended in the presence of signs of possible cardiac involvement, and iron removal therapy can prevent, improve, or even reverse cardiac dysfunction.
From the Research
Echocardiogram Detection of Iron Deposits in the Heart
- Echocardiography has the potential for early detection of cardiac involvement in patients with transfusion-dependent thalassemia (TDT) 3.
- Tissue Doppler echocardiography can detect left ventricular diastolic dysfunction, which may reflect the severity of iron overload in the heart 3.
- Recent advances in echocardiography suggest that it can equal or even outperform cardiac magnetic resonance imaging (CMR) in identifying cardiac functional abnormalities in iron overload conditions 4.
- Radiomic features extracted from echocardiography images and machine learning algorithms can predict cardiac problems caused by iron overload in patients with thalassemia major 5.
Limitations of Echocardiogram in Detecting Iron Deposits
- Diastolic dysfunction is not associated with transfusional iron burden or myocardial iron deposition in children with sickle cell anemia 6.
- Echocardiogram findings are not significantly associated with hepatic iron content or T2*-MRI in patients with sickle cell anemia 6.
- No correlation was found between echocardiographic parameters and MRI T2* in patients with thalassemia major 7.
Echocardiographic Parameters for Iron Overload Detection
- Increased pulmonary vein atrial reversal duration and mitral A-wave duration, and an E/E' ratio ≥ 11 are associated with severe iron overload in patients with TDT 3.
- Global longitudinal strain and diastolic function are abnormal in patients with thalassemia major, even in the presence of normal left ventricular ejection fraction and normal MRI T2* 7.