Cardiac arrhythmias in thalassaemia major: evaluation of chelation treatment using ambulatory monitoring.

Abstract

found post mortem. The presence of a higher end-diastolic pressure in the left ventricle in our patient is very suggestive of myocardial restriction.4 Late onset pericardial constriction has been reported only in one case,5 and, like the case reported here, pericardiectomy led to improvement. This case report shows that the absence of clinical findings within five years does not preclude the later development of significant radiation-induced heart disease. We thank Dr W Whitaker for permission to report this case, and Mr M I Ionescu, who performed the pericardiectomy.

Iron overload thalassemic cardiomyopathy: Iron status assessment and mechanisms of mechanical and electrical disturbance due to iron toxicity

“…Other arrhythmias include PR and QRS interval prolongation (65) and bradycardia in the early stage (34,66), and premature ventricular contraction (40), ST-T changes (66), QT prolongation (66), second-and third-degree atrioventricular block (65), and arrhythmias in the late stage (59). These changes are similar to those reported in iron overload patients (7,19). Further investigations on alterations of ion channels, both quantitatively and structurally, are required to explain the association of molecular and electrophysiological changes at the cellular level.…”

“…Findings in the early stage are usually accidental, including bradycardia, ST-T changes, infrequent premature atrial or ventricular contractions, first-degree atrioventricular block and evidence of left ventricular hypertrophy (18,19). In the late stage, frequent premature atrial or ventricular contractions, short runs of supraventricular tachycardia, atrial flutter and fibrillation, ventricular tachycardia and second-degree or complete heart block (including intraventricular block) have been demonstrated (7,12,19). Among these late electrocardiogram (ECG) Patients with thalassemia major have inevitably suffered from complications of the disease, due to iron overload.…”

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

“…Similar to echocardiogram, once the development of cardiac arrhythmias, such as premature atrial or ventricular contractions, first-degree atrioventricular block, atrial flutter, atrial fibrillation, ventricular tachycardia, and second-degree or complete heart block [26][27][28] , is detected by ECG, it usually implies an advanced stage of disease [29,30] . Furthermore, a normal ECG does not exclude a risk of significant arrhythmia development in iron overload patients [25] .…”

Cardiovascular Function and Treatment in β-Thalassemia Major

“…71,[211][212][213] Clinically, intra-atrial reentrant tachycardia and AF are the most common serious rhythm disturbances. 214 Ectopic atrial tachycardia and chaotic atrial rhythm may also be seen, particularly in the presence of significant cardiac iron loading. 27,44 Amiodarone is often successful in controlling atrial arrhythmias and can be a powerful temporizing measure during intensive iron chelation.…”

“…Ventricular arrhythmias are more specific for iron cardiotoxicity. 214 Frequent premature ventricular contractions, by themselves, are not specific for iron cardiomyopathy, but couplets, nonsustained ventricular tachycardia, or mixtures of frequent atrial and ventricular premature contractions should raise clinical suspicion. Historically, sudden death accounts for ≈5% of cardiac deaths in TM and is associated with severe iron overload and increased QT dispersion, which suggests iron-mediated repolarization abnormalities and torsade de pointes as a causative mechanism.…”