25th May 2025

A 21-year-old man is referred to the Cardiology outpatient clinic, where a clinical examination reveals central cyanosis, bipedal oedema, raised jugular venous pressure and bibasal crackles on auscultation of his lungs.

A 21-year-old man is referred to the Cardiology outpatient clinic, where a clinical examination reveals central cyanosis, bipedal oedema, raised jugular venous pressure and bibasal crackles on auscultation of his lungs. Echocardiography shows ‘atrialisation’ of the right ventricle with a downward displacement of the tricuspid valve. On further questioning, you find out that his mother has bipolar disorder and had taken lithium therapy throughout the pregnancy. What is the aetiology of cyanosis in this patient? 

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