Women with thalassaemia who have undergone splenectomy and have a platelet count above 600 x 10^9/l should be offered low-molecular-weight heparin thromboprophylaxis as well as low-dose aspirin (75 mg/day).

If it were only one of splenectomy OR platelet count more than 600 , then aspirin should be started.

If a woman describes symptoms of palpitations then a cardiac assessment is appropriate. Cardiac iron overload can lead to cardiac toxicity.  A detailed history, ECG and 24 hour ECG monitor assessment are needed to confirm a pathological cause.
Women with thalassaemia major and myocardial iron loading with T2* of < 10 ms are at high risk of cardiac
decompensation which may present as increasing breathlessness, paroxysmal nocturnal dyspnoea, orthopnoea, syncope, palpitations or peripheral oedema.
Desferrioxamine infusions may be indicated if there are concerns.