Definitive conclusions about QOL differences between patients managed with an ICD and those treated with antiarrhythmic drugs are difficult to make in the absence of large, randomised, controlled trials. Available evidence indicates that ICD recipients experience a brief decline in QOL from baseline but improve to pre-implant levels after one year of follow up.4
The largest clinical trial data published in final form is from the coronary artery bypass graft (CABG) Patch trial which randomised patients to ICD (n = 262) versus no ICD (n = 228) while undergoing CABG surgery.5
In contrast to May and colleagues,4
data from this trial indicate that the QOL outcomes (mental and physical) for the ICD patients were significantly worse compared to patients with no ICD. Subanalyses revealed that there was no difference in QOL for non-shocked ICD
patients versus no ICD patients. These results indicated that the ICD group who had received shocks was responsible for the significantly worse mental and physical QOL outcome scores between the groups. Collectively, these data suggest that the experience of shock may contribute to psychological distress and diminished QOL. Figure 1 details the psychological continuum a patient may experience secondary to shock.
Continuum of implantable cardioverter-defibrillator (ICD) shock response. PTSD, post-traumatic stress disorder.
Other investigators have examined patients with ICDs and compared them to patients with permanent pacemakers. Very few consistent differences can be demonstrated between these two populations. For example, Duru and colleagues6
found no differences in QOL score, anxiety or depression when comparing ICD patients with and without shock experience and pacemaker patients. ICD patients with a shock history were more likely to report limitations in leisure activities and anxiety about the ICD, but they also viewed the ICD as a “life extender”. Herbst and colleagues7
recently compared the QOL and psychological distress of four patient groups: ICD only (n = 24) v
ICD plus antiarrhythmic drug (n = 25) v
antiarrhythmic drug only (n = 35) v
a general cardiac sample (n = 73). QOL was assessed using the short form 36 (SF-36) and three supplementary scales examining sleep, marital and family functioning, and sexual problems. Comparisons were made between ICD groups and drug groups. Results indicated that there were no significant differences on the 11 QOL scales, even after controlling for age, sex, disease severity, and duration of treatment. However, significant differences were found in drug groups versus no drug groups, such that the drug treated group consistently reported greater impairment in physical functioning, vitality, emotional, and sleep functioning, as well as psychological distress. Collectively, these results suggest that QOL is maintained in ICD treated groups, while antiarrhythmic drug treatment is associated with diminished QOL and increased psychological distress.
In contrast, others have compared ICD patients to either antiarrhythmic drug treated patients or a cardiac reference group and have not found significant differences between these treated groups. For example, Arteaga and Windle8
compared three groups: ICD (n = 45), medication (n = 30), and reference group (n = 29) on QOL and psychological distress. No significant differences were observed on measures of QOL and psychological distress between the treated groups, although psychological distress was associated with lower QOL for all groups. Younger patients and patients with greater cardiac dysfunction reported reduced QOL. Similarly, Carroll and colleagues9
compared cardiac arrest survivors who received either an ICD or medications and found no significant differences in QOL. Herrmann and associates10
also compared QOL between a group of ICD and general coronary artery disease (CAD) patients and found no significant differences on measures of QOL. Moreover, ICD patients reported significantly lower levels of anxiety than the CAD reference group.
A US national survey of ICD patients and spouses (NSIRSO) parts 1 and 211
examined global QOL and psychosocial issues in 450 patients. Approximately 91% of ICD recipients reported desirable QOL, either better (45%) or the same (46%) following implantation. However, a small group of ICD recipients (approximately 15%) reported significant difficulty in emotional adjustment. Younger patients (50 years of age and under) reported better general health, but worse QOL and emotional functioning than each of the other age groups studied. ICD shock history did not have a significant effect on any of the global outcome ratings. The spouses and partners of these recipients (n = 380) provided convergent validity of the recipients' reports; no significant differences were found between raters on the 10 most common concerns. Of note, frequent ICD shocks, younger age, and being female were associated with increased adjustment difficulty. The results of these two surveys suggest that ICD recipients derive significant health related QOL benefits from ICD therapy, although some (approximately 10–20%) experience difficulty. This percentage is consistent with the expected rates of distress in comparable medical populations.