What is the diagnosis?

Beta thalassaemia intermedia
The alkali gel shows a bands at A, F and A2
The acid gel shows bands at A and F
The capillary electrophoresis confirms an elevated HbA2, the presence of some normal HbA (although much lower in quantity than expected), with a very high (66%) HbF.

What investigations would you perform urgently?

CTPA to rule out pulmonary embolism. She is at increased risk of thrombosis given her history of splenectomy, and she is clinically in right heart failure. There are three possible reasons for this: acute pulmonary embolism, chronic thromboembolic pulmonary embolism (CTEPH) or pulmonary hypertension, which is well associated with beta thalassaemia (Anthi et al).

What immediate and long-term treatment would you institute?

The CTPA showed CTEPH. The patient requires therapeutic anticoagulation. In the longer-term, she will require iron chelation and a chronic transfusion program. She should be on regular folate.

What are the long-term complications of beta thalassaemia?

Chronic haemolysis: gallstones, symptomatic anaemia, hepatosplenomegaly
Skeletal: structural deformities, osteoporosis, bony masses
Iron overload: cardiac failure, cirrhosis, endocrinopathies (hypogonadism, hypothyroidism, diabetes, growth impairment)
Pulmonary hypertension