The main finding of this study is that ToF-patients with an ICD show less favourable psychosocial functioning compared to ToF-patients without ICD and to the older acquired heart disease ICD-patients.
To our knowledge, this is the first psychosocial study carried out in this specific group, Fallot-patients with ICD. Data were compared with two control groups: Fallot-patients without ICD and older “regular” ICD-patients without ConHD. Clinically relevant areas of psychosocial functioning together with medical correlates for psychosocial outcomes were investigated, using standardized and validated questionnaires.
Psychosocial functioning and ICD therapy
Despite a younger age (40 vs. 72 years) and lower NYHA class (I vs. II), Fallot-patients with ICD scored less favourable on instruments assessing subjective health status, anxiety, satisfaction with life and coping (more negative emotions, more palliative reactions such as smoking and drinking and less seeking of social support) compared to older ICD-patients. After correction for the higher age in the ICD group using stepwise multiple regression, all conclusions drawn remained the same.
In contrast to the overall good quality of life reported before [13
], in our study we found that Fallot-patients with ICD showed a less favourable quality of life outcome than Fallot-patients without ICD. Our findings, together with the findings from literature indicate that the ConHD background of these ICD-patients cannot be the sole reason for the lower quality of life observed in this study. In fact, they confirm our hypothesis that ICD therapy in young ConHD patients is associated with worse psychosocial functioning. Between the study of Yap et al. [4
] and the start of our own study, patients with less favourable medical outcome have died in the ToF + ICD group. This means that it might even be possible that our present outcomes could have been worse as we face a positive selection of patients.
Anxiety in Fallot-patients receiving ICD therapy
We found anxiety to be a problematic psychosocial reaction for young Fallot-patients receiving ICD therapy. This is in line with the review of Sears et al. 2009 [19
]. Our results on anxiety were statistically significant and in addition clear trends were observed in the other data, also pointing towards the same direction of a less favourable psychological outcome for Fallot-patients with ICD compared to both control groups. In addition, patients reported a lower satisfaction with life.
In literature [20
], a clinical cut-off value of 8 is considered clinically significant on the anxiety scale of the HADS. Our ToF + ICD group obtained a median score of 6 and did not show a significant difference on anxiety level compared to normative data. This finding might be explained by assuming that the HADS instrument may not be sensitive enough to screen for disease-specific anxiety in this unique ConHD population. We assume that using a clinical interview, high levels of anxiety might have been found, as in the article of Bromberg et al. [21
Role of appropriate and inappropriate ICD shocks
The present data show that Fallot-patients receiving ICD therapy have a higher rate of inappropriate ICD discharges compared to “regular” ICD-patients. Despite optimal programing, 39% of the Fallot-patients with ICD suffered from one or more inappropriate ICD shocks. The inappropriate shock rate was higher than reported in previous studies in non-ConHD patients [3
]. Since Fallot-patients are known to have a high arrhythmia burden, the inappropriate shocks we found may be due to atrial arrhythmias [4
Furthermore, ToF ICD-patients are in general younger than the traditional ICD-patient group and tend to lead more active lives, practising sports and other leisure activities. These activities inducing sinus tachycardia may result in inappropriate ICD therapy. Not only the inappropriate shock rate in ToF + ICD patients was higher than that in the older ICD group but also the number of inappropriate shocks per patient was significantly higher. As most inappropriate shocks occur when the patient is fully conscious, this may have serious psychosocial consequences and it may lead to serious anxiety and stress, possibly resulting in avoidance behaviour. Our findings are in line with Vasquez et al. [7
], who showed that ICD patients who had a history of more inappropriate shocks with age below 50 and female gender were at higher risk for developing psychosocial problems. Moreover, avoidance behaviour has been reported for ICD patients, which may be a limiting factor in social and sexual activities, but also in practising sports. Out of fear for an ICD discharge, 39% of the ICD-patients avoid physical exertion [25
], even though physical exercise is well known to have a beneficial effect on health and can be effective in preventing depression.
Although there is lack of evidence in mortality benefit, the threshold for using ICD therapy in ConHD patients seems to have lowered over time. The guidelines for ICD implantation in this patient population are based on limited data. With the high rate of inappropriate shocks, balancing the benefit-risk ratio for ICD implantation remains difficult, especially taking psychosocial problems into account.
The differences in QRS duration as seen in Table could be explained by the ConHD background in combination with pacemaker therapy differences between groups. ToF-patients have a higher QRS duration as a result of right ventricular dilatation, diminished function, or post-surgery for their ConHD background. Some of the patients in the ToF + ICD group also received constant pacing therapy next to the ICD therapy which may also have resulted into a longer QRS duration. The long QRS duration seen in the ToF + ICD group can also be the result of selection, as a QRS duration >180 ms is a predictor for SCD and may have been used as a criterium for ICD implantation [26
]. Despite the diminished RV function, patients in the ToF + ICD group were in good clinical condition with the majority being in NYHA class I.
When considering ICD therapy in young patients, the psychosocial impact should be taken into account. The findings in this study provide a solid argument for careful assessment and counselling in patients with Tetralogy of Fallot. The threshold for ICD implantation should be high, especially in case of primary prevention. In patients needing an ICD, routinely applied comprehensive and multidisciplinary psychosocial aftercare is advised. We see an opportunity for a shared decision-making model in this situation. In this way, patients can become well informed about all possible consequences of ICD therapy, and can decide the best treatment option together with the clinician.
In order to facilitate acceptance of ICD therapy, we recommend cognitive behavioural techniques such as psycho-education, cognitive re-appraisal and relaxation techniques to improve quality of life of these patients. These techniques have been found to improve the quality of life in the “general” older ICD population [7
The patients included in this study were all followed in a tertiary (academic) medical centre. Therefore, this study may not be representative for all Fallot-patients. In addition, although we tried to create comparable groups, some differences were present. Furthermore, because of the small sample size, often encountered in these patient groups, several nearly significant trends were observed. With a larger sample size these trends might have become significant.
Although no significant differences were found between the three groups, a trend was visible in which the older ICD patients more often had male gender.
Unfortunately, data regarding psychosocial interventions (so called “medical consumption” or “psychotherapeutic counselling”) are not systematically available.
Furthermore, as could be expected, a significant age difference was found between the ToF + ICD and the—by definition—older ICD group, which resulted in a later age at implantation in the ICD group. In addition, patients with the Belgian nationality (N = 8) were only found in the ToF + ICD group. To which extent these inter-group differences have influenced our results is unknown.
Despite the fact that patients in the ICD group were more often in NYHA class II compared to the ToF and the ToF + ICD group, we remarkably found that our younger NYHA class I ToF + ICD patients obtained less favourable results than the other ICD group with worse NYHA class. This noteworthy finding reflects the psychosocial importance of our results in the ToF + ICD group.
Future research should investigate the role of inappropriate shocks on psychosocial outcome in a larger cohort, as the current cohort was not large enough to perform further subanalyses. In addition, the impact of ICD therapy in young adults with ConHD on activities such as practising sports, sexuality and driving a car [29
] should be studied. We recommend using a semi-structured clinical interview to assess these points, as questionnaires may not be specific enough.
Different programing strategies, such as the application of antitachycardia pacing therapy and higher rate cut-offs for arrhythmia detection, may prevent inappropriate ICD therapy and may have a beneficial effect on psychosocial functioning.
Recently, the subcutane ICD (sICD) has been introduced for patients requiring ICD therapy [30
]. In this study, sICD therapy appeared to have a very low rate of inappropriate shocks. This therefore may be a good alternative for ConHD patients who require ICD therapy and suffer from a lot of inappropriate shocks. The sICD is relatively easy to implant, and because the leads are subcutaneous, replacement and complication rates appear to be lower as well. Future research could concentrate on the application and psychosocial impact of having an sICD in ConHD patients.