Coldness and pain in your feet may indicate reduced blood flow to your legs, often due to peripheral artery disease or other circulation problems. It may also be related to diabetes, nerve damage, or blood clot issues. You should see a doctor promptly for a proper diagnosis and to start the appropriate treatment. In the meantime, keep your feet warm, avoid sitting for long periods, and do not smoke, as smoking can worsen circulation.

You should not reduce the dose or stop Bosentan or Sildenafil on your own, as this may worsen your pulmonary arterial hypertension. Please talk to your doctor, who can review your condition and gradually adjust your dosage or treatment plan if needed.

Since your father has both severe pulmonary hypertension and liver cirrhosis, any surgery carries very high risks and is generally not recommended. In rare cases, a combined heart-lung and liver transplant may be considered, but it is a highly complex procedure suitable only for a few carefully selected patients. His doctors will need to carefully weigh all risks and benefits before deciding whether such surgery is possible.