Table 1.

List of ESC QIs for the management of VA and the prevention of SCD

Domain 1. Structural QIs
QI 01M01: Healthcare centres with inpatient service, which have a dedicated team to deliver cardiopulmonary resuscitation (CPR) 24/7 with a written CPR protocol.
Numerator	Healthcare centres with dedicated team to deliver CPR 24/7 with a written CPR protocol.
QI 01M02: Healthcare centres involved in the management of SCA survivors and those at risk of SCD that have available protocols for the implementation & surveillance of remote monitoring for patients with CIED.
Numerator	Healthcare centres with available protocols for the implementation & surveillance of remote monitoring for patients with CIED.
Domain 2. Screening and diagnosis
QI 02M01: Proportion of young (<50 years) unexplained SCD victims who are referred for comprehensive autopsy including cardiac histopathology, post-mortem genetic testing, and, where indicated, toxicology.
Numerator	Number of young (<50 years) unexplained SCD victims who are referred for comprehensive autopsy including cardiac histopathology, post-mortem genetic testing and, where indicated, toxicology.
Denominator	Number of young (<50 years) unexplained SCD victims.
QI 02M02: Proportion of SCD victims with likely heritable phenotype whose families receive a clinical and/or genetic workup for inherited cardiovascular conditions.
Numerator	Number of SCD victims with likely heritable phenotype whose families receive a clinical and/or genetic workup for inherited cardiovascular conditions.
Denominator	Number of SCD victims with likely heritable phenotype.
QI 02M03: Proportion of unexplained SCA survivors who undergo pharmacological provocation testing.
Numerator	Number of unexplained SCA survivors who undergo pharmacological provocation testing.
Denominator	Number of unexplained SCA survivors.
QI 02M04: Proportion of patients with arrhythmogenic right ventricular cardiomyopathy who undergo LGE-CMR at the time of diagnosis.
Numerator	Number of patients with arrhythmogenic right ventricular cardiomyopathy who undergo LGE-CMR at the time of diagnosis.
Denominator	Number of patients with arrhythmogenic right ventricular cardiomyopathy.
Domain 3. Risk stratification
QI 03M01: Proportion of patients with hypertrophic cardiomyopathy (HCM) who undergo an assessment of their risk of SCD using the HCM SCD risk score at the time of initial evaluation.
Numerator	Number of patients with hypertrophic cardiomyopathy who undergo an assessment of their risk of SCD using the HCM SCD risk score at the time of initial evaluation.
Denominator	Number of patients with hypertrophic cardiomyopathy.
QI 03M02: Proportion of patients with hypertrophic cardiomyopathy who undergo LGE-CMR at the time of initial evaluation.
Numerator	Number of patients with hypertrophic cardiomyopathy who undergo LGE-CMR at the time of initial evaluation.
Denominator	Number of patients with hypertrophic cardiomyopathy.
Domain 4. Patient education and lifestyle modifications
QI 04M01: Proportion of patients with arrhythmogenic cardiomyopathy who receive counselling about avoidance of high intensity and endurance sports.
Numerator	Number of patients with arrhythmogenic cardiomyopathy who receive counselling about avoidance of high intensity and endurance sports.
Denominator	Number of patients with arrhythmogenic cardiomyopathy.
QI 04M02: Proportion of patients with congenital LQTS who receive counselling about all the following: the risk of electrolyte abnormalities (e.g. diarrhoea and vomiting, but also use of diuretics), the avoidance of QT-prolonging drugs (www.crediblemeds.org), and the avoidance of genotype-specific triggers for arrhythmias.
Numerator	Number of patients with congenital LQTS who receive counselling about all the following: the risk of electrolyte abnormalities (e.g. diarrhoea & vomiting, but also use of diuretics), the avoidance of QT-prolonging drugs, and the avoidance of genotype-specific triggers for arrhythmias.
Denominator	Number of patients with congenital LQTS.
QI 04S01: Proportion of patients with an ICD/CRT-D who receive counselling about living with a defibrillator.
Numerator	Number of patients with an ICD/CRT-D who receive counselling about living with a defibrillator.
Denominator	Number of patients with an ICD/CRT-D.
Domain 5. Pharmacological treatment
QI 05M01: Proportion of patients with congenital LQTS who receive beta-blockers.
Numerator	Number of patients with congenital LQTS who receive beta-blockers.
Denominator	Number of patients with congenital LQTS.
Domain 6. Device therapy
QI 06M01: Proportion of VT/VF cardiac arrest survivors (or those with spontaneous sustained VT causing syncope or haemodynamic instability) without a reversible cause who have a life expectancy >1 year and receive secondary prevention ICD implantation.
Numerator	Number of VT/VF cardiac arrest survivors (or those with spontaneous sustained VT causing syncope or haemodynamic instability) without a reversible cause who have a life expectancy >1 year and receive secondary prevention ICD implantation.
Denominator	Number of VT/VF cardiac arrest survivors (or those with spontaneous sustained VT causing syncope or haemodynamic instability) without a reversible cause who have a life expectancy >1 year.
QI 06M02: Proportion of patients with ischaemic cardiomyopathy, NYHA class II-III who have EF≤35% despite ≥3 months of OMT and life expectancy > 1 year who receive ICD for primary prevention of SCD.
Numerator	Number of patients with ischaemic cardiomyopathy, NYHA class II-III who have EF≤35% despite ≥3 months of OMT and life expectancy > 1 year who receive ICD for primary prevention of SCD.
Denominator	Number of patients with ischaemic cardiomyopathy, NYHA class II-III who have EF≤35% despite ≥3 months of OMT and life expectancy > 1 year.
QI 06M03: Proportion of patients with primary prevention ICD whose device is programmed to a prolonged detection strategy and/or high-rate programming strategy.
Numerator	Number of patients with primary prevention ICD whose device is programmed to a prolonged detection strategy and/or high-rate programming strategy.
Denominator	Number of patients with primary prevention ICD.
Domain 7. Catheter ablation
QI 07M01: Proportion of patients with ischaemic cardiomyopathy and recurrent, symptomatic sustained monomorphic VT despite chronic amiodarone therapy who receive VT ablation.
Numerator	Number of patients with ischaemic cardiomyopathy and recurrent, symptomatic sustained monomorphic VT despite chronic amiodarone therapy who receive VT ablation.
Denominator	Number of patients with ischaemic cardiomyopathy and recurrent, symptomatic sustained monomorphic VT despite chronic amiodarone therapy.
Domain 8. Outcomes
QI 08M01: All-cause mortality at 30 days following VT ablation.
Numerator	Number of patients who died from any cause within 30 days following VT ablation
Denominator	Number of patients who underwent VT ablation.
QI 08M02: Survival to hospital discharge after cardiac arrest
Numerator	Number of patients who survive to hospital discharge after cardiac arrest
Denominator	Number of patients admitted with cardiac arrest
QI 08S01: Procedural complications 30 days following ICD implantation [ICD-related bleeding, pneumothorax, cardiac perforation, tamponade, pocket haematoma, lead displacement, infection (all requiring intervention), or death].
Numerator	Number of patients who develop any procedural complication [ICD-related bleeding, pneumothorax, cardiac perforation, tamponade, pocket haematoma, lead displacement, infection (all requiring intervention), or death] within 30 days following ICD implantation.
Denominator	Number of patients who undergo ICD implantation.
QI 08S02: ICD-related infections up to 1 year following ICD implantation, replacement, or revision.
Numerator	Number of patients who develop ICD-related infection within 1 year following ICD implantation, replacement, or revision.
Denominator	Number of patients who undergo ICD implantation, replacement or revision.
QI 08S03: Procedural complications 30 days following VT-ablation (vascular complications, tamponade, stroke, complete heart block).
Numerator	Number of patients who develop any procedural complication (vascular complications, tamponade, stroke, complete heart block) within 30 days following VT-ablation.
Denominator	Number of patients who undergo VT-ablation.

CIED = cardiac implantable electronic devices; CRT = cardiac resynchronization therapy; ESC = European Society of Cardiology; ICD = implantable cardioverter defibrillator; LGE-CMR = late gadolinium enhancement-cardiac magnetic resonance; LQTS = long-QT syndrome; NYHA = New York Heart Association; OMT = optimal medical therapy; QIs = quality indicators; SCD = sudden cardiac death; SCA = sudden cardiac arrest; VA = ventricular arrhythmias; VT = ventricular tachycardia; VF = ventricular fibrillation.