Arrhythmias, Cardiac 1 Article 1 Cardiomyopathy, Hypertrophic 1 Defibrillators, Implantable 1 Humans Quality of Life 1 acetylsalicylic acid 1 adolescent 1 adult 1 atenolol 1 backache 1 beta adrenergic receptor blocking agent 1 cardiovascular magnetic resonance 1 case report 1 cerebrovascular accident 1 child 1 clinical article 1 clinician 1 colecalciferol 1 diltiazem 1 dizziness 1 drug dose increase 1 dyspnea 1 echocardiography 1 emergency ward 1 endocarditis 1 faintness 1 fatigue 1 female 1 fluid retention 1