Estimation of the requirement for implantable cardioverter defibrillators for the primary prevention of sudden cardiac death post-myocardial infarction based on UK national guidelines (2006)

AIMS: To assess the impact of the new UK National Institute for Health and Clinical Excellence (NICE) guidelines on the incidence of implantable cardioverter defibrillator (ICD) indications for the primary prevention of sudden cardiac death following myocardial infarction (MI). METHODS AND RESULTS: We performed a retrospective single centre study in a District General Hospital. The transthoracic echocardiogram reports of all patients with a discharge diagnosis of MI during a 6-month period were studied. We reviewed the notes of all patients with an estimated left ventricular ejection fraction (LVEF) of <35% and used UK national guidance to assess the incidence of potential ICD indications. Five hundred and forty-six patients had a discharge diagnosis of MI. Fifty had estimated LVEF <35% and 8-11 of these met the NICE post-MI primary prevention criteria for ICD implantation. This gives an estimated incidence based upon our local population of 29-39 patients/million/year. Most of these patients (64-88%) were identified purely by ECG criteria (QRS > 120 ms) and LVEF. CONCLUSION: The latest published UK ICD data give a new implantation rate of approximately 40/million/year. Combining our results with published data for NICE secondary prevention indications gives a combined ICD indication incidence of approximately 105-115/million/year. This suggests there is currently significant under-provision of ICD therapy in the UK.