Patients with an implantable cardioverter defibrillator (ICD) are at increased risk of anxiety disorders. In turn, anxiety has been identified as a precipitant of ventricular arrhythmias. Anxiety may in part be attributed to concerns about the ICD firing, but the relationship between ICD concerns, psychological morbidity, and shocks has not been systematically investigated. We examined the relative importance of experienced shocks versus subjective concerns about the ICD as determinants of anxiety and depressive symptoms in ICD patients.

Consecutive surviving patients (n = 182, response rate = 82%) having had an ICD implanted between October 1998 and January 2003 at the Erasmus Medical Centre Rotterdam were asked to fill in the ICD Patient Concerns Questionnaire and the Hospital Anxiety and Depression Scale. Clinical variables were obtained from the patients' medical records.

A total of 55 (30%) patients had received a shock from the ICD. Although patients who had experienced a shock scored higher on ICD concerns, ICD concerns was the only independent determinant of anxiety (odds ratio 6.35, 95% CI 2.84-14.20) and depressive symptoms (odds ratio 2.29, 95% CI 1.06-4.96) adjusting for shocks and all other factors.

Patient concerns about the ICD may be an important indicator of psychosocial adjustment. Screening for ICD patient concerns using the ICD Patient Concerns Questionnaire may identify patients at risk for psychological morbidity after ICD implantation.