Hi welcome to hcm
I understand your query and concern.
The condition of your father with a pace maker,defibrillator with EF 20% should always be attended immediately to avoid further complications.He should get an ECG,2D Echo ,chest x ray,complete blood picture,serum electrolytes and
creatinine,ABG analysis for every 2 weeks to evaluate functioning of kidney,heart and lungs.Drugs like Digoxin and digitalis, clavix,
ecosprin,betaloc ,pantop should be taken regularly to prevent further worsening of the condition.Do not stop giving medication until doctors advise.24 HOUR Holter ECG monitoring is required to know the pace maker working condition.Also periodic checkup and change of battery is needed.Report to emergency if symptoms like
chest pain,
shortness of breath,
dizziness,weakness etc occur.Consult your cardiologist for expert management.
Post your further queries if any,
Thank you.