|Year : 2019 | Volume
| Issue : 1 | Page : 33-39
Knowledge and attitude regarding permanent pacemaker and the quality of life of patients after permanent pacemaker implantation
Deborah Snegalatha1, Jasmin Anand1, Bala Seetharaman1, Bobby John2
1 College of Nursing, CMC, Vellore, Tamil Nadu, India
2 Department of Cardiology, CMC, Vellore, Tamil Nadu, India
|Date of Web Publication||09-Oct-2019|
Ms. Deborah Snegalatha
College of Nursing, CMC, Vellore, Tamil Nadu
Source of Support: None, Conflict of Interest: None
Cardiac pacing is an emerging lifesaving procedure that is being widely used in the recent times. Therefore, it is considered vital for the healthcare professionals to be aware of patients' knowledge and experience after the cardiac device implantation and also the impact these implanted devices have on their day-to-day life. This study was conducted with an aim to assess the knowledge and attitude of patients regarding permanent pacemakers (PMs) and their quality of life (QOL) after the permanent PM implantation. A descriptive cross-sectional study design was used in this study. A total of seventy patients were chosen by total enumerative sampling technique among those patients attending the cardiology outpatient department, PM clinic and selected cardiology wards of a tertiary care centre in South India. A knowledge questionnaire, an attitude scale and RAND Short-Form-36 health survey were used to collect data. The mean age of the study patients was 61.71 ± 12.42 years, and 60% accounted for men. The median duration of implantation was 2.9 ± 5.21 years. Majority of the participants (54.3%) had moderately adequate knowledge, 55.7% of the participants had moderately favourable attitude and 46% of them experienced moderate QOL. There were a positive correlation between the knowledge of participants and their QOL (r = 0.340; P = 0.004) and a statistically significant positive correlation between the attitude of participants and their QOL (r = 0.559; P = 0.001). A significant association between attitude and age was found. Conscious effort must be taken to help patients cope better and experience good QOL through systematic teaching after the PM implantation. This will help patients to function maximally and live life to their best capacities in the family and society.
Keywords: Attitude, knowledge, permanent pacemaker, quality of life
|How to cite this article:|
Snegalatha D, Anand J, Seetharaman B, John B. Knowledge and attitude regarding permanent pacemaker and the quality of life of patients after permanent pacemaker implantation. Indian J Cont Nsg Edn 2019;20:33-9
|How to cite this URL:|
Snegalatha D, Anand J, Seetharaman B, John B. Knowledge and attitude regarding permanent pacemaker and the quality of life of patients after permanent pacemaker implantation. Indian J Cont Nsg Edn [serial online] 2019 [cited 2019 Oct 18];20:33-9. Available from: http://www.ijcne.org/text.asp?2019/20/1/33/268693
| Introduction|| |
Timing is everything when it comes to the functioning of the heart. Blood cannot flow where it needs to without a strong heartbeat, and to have a strong heartbeat, it must be steady. A heartbeat, in essence, is a contraction of the heart. Normally, the pacemaker (PM) of the heart, the sino atrial node, generates an electrical impulse that is carried to the lower chambers of the heart, the ventricles. Any interruption in the electrical impulses of the heart or any disease of the sinus node can lead to heart block and arrhythmia requiring interventions to keep the heart beating effectively and efficiently.
Cardiac pacing has rapidly evolved as a vital intervention since its introduction by Zoll in 1952, and the first cardiac PM was implanted in the year 1958 by Dr. Ake Sening and Er. Rune Elmqvist in Stockholm. A permanent cardiac PM is an implantable device used to maintain sufficient heart rate when natural mechanisms fail, either as a result of a deficiency with the natural PM or the conduction system in the heart. The impaired cardiac rhythm is initiated and maintained through cardiac pacing where very low electrical energies are delivered to the heart repetitively. Pacing may be temporary, with an external pulse generator, or permanent, with an implanted pulse generator. More recently, the indications for cardiac pacing have extended beyond symptomatic bradycardia and include conditions such as hypertrophic obstructive cardiomyopathy and prevention of atrial fibrillation.
PMs, in addition to being a lifesaving procedure, help improve the quality of life (QOL). Cardiologists expect that most patients will be able to return to their premorbid level of functioning post implantation of a PM. Similarly, international studies done among patients living with permanent PMs have focused more on the patient's sense of well-being after implantation rather than the patient's perception of daily routine activities with an implanted device.
Initially, PMs were made with a fixed frequency which did not change according to the patient's heart function. The mismatch between the fixed frequency and the patient's heart rate caused problems at multiple levels. However, the advances in technology have made it possible to innovate rate-responsive PMs which adapt to patients' needs, allow them maintain haemodynamic balance and enhance them to tolerate better physical activity leading to better QOL. With the tremendous advances in cardiac pacing, the increasing indications and the various modes of pacing during the past five decades, the evolution of PM therapy has moved from not just being a lifesaving procedure but the one that is aimed at improving the Health-Related QOL (HRQOL).
Knowledge assessment and educating these patients in helping them to lead an active life after a PM implantation present many challenges for nurses who are involved in care. Awareness about PMs among these patients will reduce their misconceptions which impede them from leading a normal life after permanent PM implantation (PPI).
PM implantation is often a difficult situation for the patient and his/her family and is influenced by several factors such as early and late complications after surgery, the need for regular follow-up and the awareness that it is a lifelong treatment. Often, patients are not prepared for the major changes that may be needed in almost every aspect of their life. It affects patients' physical, mental and functional status and their social relationships. Therefore, nurse–patient interaction provides key opportunities for educational support and interventions which aim at facilitating positive patient and family adjustments after the PPI.
The present study was undertaken with the following objectives:
- Assess the knowledge and attitude regarding permanent PMs among patients who have undergone a PPI
- Assess the QOL of patients who have undergone PPI
- Find out the relationship between knowledge and attitude regarding permanent PMs and QOL among patients who have undergone PPI
- Determine the association of knowledge and attitude regarding permanent PMs among patients who have undergone a PPI with the selected sociodemographic and clinical variables
- Determine the association of QOL among patients who have undergone a PPI with their selected sociodemographic and clinical variables.
| Methods|| |
A descriptive cross-sectional study design was adopted for this study to assess the knowledge and attitude regarding permanent PMs and the QOL among patients who underwent PPI. Patients who were above 18 years of age; those who had permanent PMs for a period of 4 months or more; those who could read, understand and write Tamil, English, Hindi and Bengali; those who had either come for follow-up visits to the outpatient departments and PM clinics or those who were readmitted in the selected cardiology wards of the tertiary care centre for various other health concerns were recruited for the study. Patients who were critically and chronically ill were excluded from the study. Total enumerative sampling technique was employed, and a total of seventy patients participated in the study.
The instrument used for data collection was a structured self-reported questionnaire, and the instrument had four parts. The first part with two sections constituted the demographic profile of the participants which included their age, sex, location of residence, religion, marital status, educational status, occupation, monthly income and an instrument to collect the clinical profile of the participants which included their duration of illness, duration of implantation, indication for PPI, comorbidities, regular medicine intake, any complications encountered after PPI and the centre where the PM implantation was done. The second part was a self-reported questionnaire with 24 questions to assess the knowledge regarding permanent PMs, which was prepared by the investigator. Its minimum score was 0 and the maximum score was 24. The content validity index (CVI) for this tool was 0.95. The third part was a self-reported 5-point Likert scale developed by the investigator with a total of ten statements to assess the participants' attitude after PPI. The CVI for this scale was established as 0.91. The content validity of both the tools was established with the help of nursing and medical experts. The fourth part was a standardised tool, the RAND 36-item Short-Form Health Survey (SF-36), used to assess their QOL after the PPI. Reliability coefficients for all dimensions for this tool were >0.74. The test–retest reliability of the RAND SF-36 was found to be excellent.
Ethical approval was obtained from the college's research committee. Written informed consent was obtained from the study participants. Demographic and clinical data were collected by the investigator using interview technique. The questionnaire on knowledge, attitude and QOL was given to the participants in their language, according to their convenience. Confidentiality with the information was achieved by maintaining anonymity of the participants. Analysis of the collected data was done using the software SPSS version 17.0 (IBM company, Newyork), and descriptive and inferential statistics were used.
| Results and Discussion|| |
[Table 1] summarises that 60% of the patients who had undergone PPI were above 60 years of age, with the average age being 61.7 years. This is supported by the data from the Tehran Heart Center, where they did a National Survey of Cardiac PMs and cardioverter defibrillators in 2006. In that survey, 59.1% and 13.9% of patients were in the age group of 61–80 years and more than 80 years, respectively, and the average age for PM insertion was 65.4 years. The proportion of men who underwent PPI was higher accounting for 60% of the patients, which is supported by the data from a study done by van Eck et al. in 2008 to assess the predictors of QOL 1 year after PM implantation. The number of men in their study accounted for 57.6%. The reason for the higher number of men with PPI could not be established through this study.
|Table 1: Distribution of participants with respect to sociodemographic characteristics|
Click here to view
Majority (74.3%) of the participants were residing in urban areas, which could be attributed to both increased awareness and accessibility to healthcare facilities. Of the total, 91.4% of patients were married. Majority of them had schooling up to higher secondary grade (60%). Furthermore, 41% of patients had retired from service, which was followed by homemakers who accounted for 31.4%. There were 35.71% of patients whose monthly income ranged between Rs. 5000 and 15,000.
The findings related to clinical variables [Table 2] revealed that 72.9% of patients had been having the illness for >3 years, and majority (51.4%) of them have had the PPI for >3 years. Thus, the median duration of illness was 5 ± 6.2 years, and the median duration of implantation was 2.9 ± 5.2 years. The primary indication for PPI in majority of the patients (37.1%) at implant was diagnosed to be complete heart block and sick sinus syndrome. There were 78.6% of participants who were taking some form of medication. Participants who had encountered complications after PPI constituted only 4.3%. Of all the participants, 77.1% had their PM implanted at the study institution.
|Table 2: Distribution of participants with respect to clinical characteristics|
Click here to view
As far as the indications for PPI, similar and differing results were found in a population-based study which assessed the temporal trends in PPI; it was found that the indication for PPI had a trend towards implantation for indications other than atrioventricular block, including sinus node dysfunction and carotid sinus hypersensitivity. Permanent Pace Maker for congestive heart failure or hypertrophic cardiomyopathy comprised <3% of the total. The mean duration since first implantation with PMs was 4.1 years (ranging from <1 to 15 years), according to a study done by Aqeel et al.
The mean knowledge score of the participants regarding permanent PM was 14.97 (±3.26) out of the total score of 24. Majority of the patients (88.6%) considered that permanent PM was a cure for their heart disease. Most of them (90%) knew that earlier symptoms of syncopal attacks, tiredness and giddiness will be relieved after PPI. Nearly 25.7% of the participants reported that PM will be removed once they felt better or when they remained symptom free for a certain period of time. Of the total, 77.1% of the participants were not aware of the reason why pulse rate was checked at home. Almost 38.6% of the participants said that they will not be able to perform activities that they did prior to PPI. Majority (77.1%) of the participants were not aware of the pressure caused by lying on the same side where the PM was implanted. Among the participants, 34.3% said that sexual activity had to be avoided after PPI. Only 37.1% of the patients stated that magnetic resonance imaging (MRI) is an unsafe diagnostic procedure after PM was implanted, and the rest 62.9% were not aware that MRI is an unsafe procedure after PPI. Most (84.3%) of the participants said that it was necessary to report about their PPI when they underwent any procedures in a hospital. Sixty percent of the participants reported that lightning does not have any adverse effects on the functioning of the PM. Some participants (22.9%) did not know about the precautions with regard to the use of mobile phones. Participants were not aware of how long was the life of a PM's battery (48.6%) and were not aware (32.9%) that the battery will need replacement. Majority (67.1%) were also not aware that the PM identification card had to be carried along with them wherever they go.
In another similar study, 30.1% (28) of the patients felt that they could not sleep on the side of their PM. Only 45% of the patients knew that they could use their mobile phones safely. Most of the patients in their study did not know that they should avoid an MRI procedure, which is currently contraindicated in PM patients. With advancing age and expanding indications for pacing and prophylactic management of many cardiac illnesses, the number of patients requiring cardiac devices is on the rise. Many of these patients derive benefit from the diagnostic power of MRI. The patients who have undergone permanent PMs are not aware that MRI and other diagnostic procedure are unsafe and need to be avoided.
Rassin et al. stated that although PM devices do not have an adverse impact on lifestyle, they induce anxiety related to the patient's activities and lifestyle. Their study which included eight categories, representing common issues of patients who had undergone a PM implantation, raised concerns related to motion and effort, environmental influences, personal hygiene, knowledge related to PM operation, medical treatment, eating and drinking and clothing and general questions. The findings show that the common factor for most of the questions was the loss of confidence in the various aspects of life.
The current study findings [Figure 1] reveal that overall 54.3% of the participants had moderately adequate knowledge. Adequate knowledge was found among 17.1% of the participants and the rest (28.6%) of the participants had inadequate knowledge regarding the various aspects of permanent PMs, the activities which can be safely performed and those that cannot be safely performed. Poor knowledge of PMs was found among the majority of patients with PPI (87.3%) prior to an educational intervention in another study conducted in Egypt. Findings from this study and also from other studies show that patients need accurate and consistent information and reinforcement about life with permanent PM after PPI.
|Figure 1: Distribution of participants according to their level of knowledge.|
Click here to view
The assessment of attitude of patients [Figure 2] regarding permanent PMs after PPI revealed that 55.7% of the patients had moderately favourable attitude, only 2.9% of them had unfavourable attitude and the rest 41.4% of the patients had a favourable attitude. The mean (standard deviation [SD]) attitude score of the participants was 36.00 (±5.80), and the total possible score was 50, showing better overall attitude towards PPI.
|Figure 2: Distribution of participants according to their level of attitude.|
Click here to view
A few of the participants (5.7%) disagreed that living a normal life after a PPI was possible. In addition, 31.4% of the patients believed that they were able to perform all those activities that the friends of their age perform. Nearly 31.4% of the patients did not get worried because of the presence of the permanent PM, and majority of the patients believed that they had good family support (55.7%) and their hope and trust in God enables them (77.1%) to lead a normal life after PPI. Some participants (31.4%) strongly agreed and 10% agreed that they felt compelled to stay indoors all the time because they had PPI.
In this study, 36% of the patients experienced poor QOL, 46% experienced moderate QOL and only 18% experienced good QOL after a PPI as depicted in [Figure 3]. The mean (SD) QOL score was 2081.14 (±581.52).
|Figure 3: Description of participants according to their quality of life.|
Click here to view
Among the eight domains that make up the SF-36 assessment of QOL, it was observed that the mean scores were lower in role limitations due to their physical health and emotional problems, accounting for a potential decrease in overall QOL experienced by these patients after PPI [Figure 4]. The mean SF-36 scores for the social component were comparatively higher.
|Figure 4: Description of the mean Short-Form 36-item scores for the different domains of quality of life of patients who have undergone a permanent pacemaker implantation|
Click here to view
In a study done to assess the long-term QOL in patients with bradycardia PM implantation, higher values for all SF-36 subscales were observed 1 year after implantation compared to pre-implantation values, with the exception of general health scores, which subsequently showed lower scores 4 years after the implantation. Similarly, the observed scores for physical functioning subscale were higher during the 1st year after implantation, with gradual decline observed thereafter. These findings may explain the lower overall QOL scores in the present study where the majority of participants were above 1 year post-PPI. The Role Limitations due to Physical Health Problems (RP), Role Limitations due to Emotional Problems (RE), Social Functioning (SF) and General Mental Health subscales showed higher scores throughout the 7.5-year observational period, whereas the scores were lower in this study post-PPI. All the SF-36 subscale scores were substantially lower in patients with PM compared to the general population (P < 0.001) except for pain and general health perception in another study. In patients with PM, the presence of comorbidities, gender and age were significantly associated with the overall physical component score (mean 38.8 ± 27 SD), whereas the overall mental component score (mean 46.8 ± 27.0 SD) was associated with gender and age.
A study was conducted among 42 patients to assess the change in QOL in patients with permanent cardiac PMs – a 6-month follow-up study. Follow-up interviews were conducted at the 2nd, 4th and 6th months after PPI. The patients experienced moderate QOL (62.4 ± 15.9 on a scale of 97) before PM implantation and the QOL improved statistically significantly after PM implantation (P< 0.05). The QOL reached a peak at the end of the 4th month, and the scores decreased at the end of the 6th month versus the 4th month (P< 0.05). The study also reported statistically significant improvement in general well-being, sleeping, appetite, physical activity and physical symptoms (P< 0.05), but not in cognitive function, social participation, work capability and sexual function (P > 0.05). Here, the patients' major determinant of QOL pre- and post-PM implantation was distress resulting from their experience of arrhythmias. In the current study, even after PPI, proportionally, most patients (46%) reported moderate QOL and only 18% reported good QOL. Mitro et al. in their study stated that it was clearly evident that PM implantation results in the improvement of HRQOL.
As the baseline scores of QOL before PPI were not measured in this study, it is hard to conclude whether these proportions were different before and actually improved after PPI. It is also important to note that few other studies reported a decline in QOL after the 1st year post-PPI.,,
The current study findings [Figure 5] reveal that there is a statistically significant positive correlation between the knowledge of participants regarding permanent PM and their QOL (r = 0.340; P = 0.004). The study findings show that as the knowledge of patients increase, there is a significant increase in the QOL experienced by them. A similar study done to assess the relationships among knowledge, uncertainty and QOL among ninety patients with implantable cardiac defibrillator (ICD) reported statistically significant relationships between uncertainty and QOL, but ICD knowledge was not significantly related to uncertainty or QOL. This was contradictory to the current findings. Similarly, a cross-sectional survey on 52 patients conducted to assess the association among adherence, knowledge and QOL on anticoagulation control found that knowledge about warfarin therapy and the impact of warfarin on QOL were not significantly associated with anticoagulation control, which is in contrary to the current study findings.
|Figure 5: Relationship between knowledge of participants and their quality of life.|
Click here to view
A study was conducted by Wang et al. to evaluate the HRQOL in adolescents with heart disease and examine its relationship with the adolescents' knowledge and understanding of their congenital heart disease, its severity and its relationship to the degree of anxiety and depression, feeling of optimism and the sense of coherence experienced by the adolescents together with their social support. It was found that the HRQOL was positively correlated with a good knowledge of their cardiac condition (r = 0.31, P < 0.01), low levels of anxiety and depression (r = −0.57, P < 0.001), feelings of optimism (r = 0.39, P < 0.001), adequate social support (r = 0.27, P < 0.01) and a strong sense of coherence (r = 0.24, P < 0.01). The study results support the present study findings that QOL is related to knowledge.
Subsequently, the correlation between the attitude of patients after PPI and their QOL reveals a statistically significant positive relationship (r = 0.559; P = 0.001) [Figure 6]. Hence, it is interpreted that when patients have favourable attitude regarding their health issues and concerns, then they experience good QOL. In the current study, it was found that patients who had unfavourable attitude after PPI experienced poor QOL.
The findings of this study revealed that there was no significant association between the knowledge of participants and the selected sociodemographic variables such as age, sex, educational status, occupation or monthly family income. The findings suggest that participants >60 years of age and postgraduates had moderately adequate knowledge compared to others in the group. Furthermore, there is no significant relationship between the knowledge of participants regarding permanent PMs and the selected clinical variables such as duration of PPI and the place or hospital where PM was implanted. In another study, it was found that patients with adequate literacy had higher knowledge regarding the disease condition.
In the current study, a statistically significant association between attitude and age of the patients (P = 0.001) was observed. Hence, it is implied that as the age of patients increases, the attitude of patients also increases favourably. There is no other significant association between the attitude of participants and the sociodemographic variables. Furthermore, there is no significant relationship between the attitude of participants and the selected clinical variables.
No significant association was found between the QOL of patients after PPI and the sociodemographic variables. There was also no significant relationship between QOL of the patients after permanent PMs and the selected clinical variables such as duration of PPI and the place or hospital where PM was implanted. In a study done to assess the correlation between functional class and QOL among cardiac PM users by Cunha et al., it was stated that a negative correlation was observed between age and QOL in the functional capacity domain, a main determinant of physical condition. Sossong in her study in 2007 has also reported a lower QOL among young patients who were recipients of intracardiac device, a form of implanted cardiac device. Statistically significant relationships were also confirmed with respect to patients' age (P ≤ 0.027, r ≥ −0.309). Older patients experienced lower QOL according to Kurucová et al. in their study regarding QOL of patients with a permanent PM done in 2013. Similar associations were not found in this study.
Previous study results reveal that patients with their spouses as their primary caregivers had significantly better improvement in their QOL after the PPI. Statistically significant differences (P ≤ 0.029) were found in individual areas of life regarding marital status. Married patients reported a higher QOL. In the current study, no such significant association was observed between marital status and the improvement in QOL.
| Conclusion|| |
The use of medical devices in patient care is expanding widely since its introduction in the 20th century. It is important to evaluate what people living with a permanent PM know about the implanted cardiac device and the impact of this knowledge on their QOL. This study although measured the knowledge on PPI and the patients' QOL at one point of time provides an understanding of the patients' level of knowledge and their QOL. By understanding patients' perspective regarding permanent PMs, nurses will be able to assist these patients in their transitional process of learning to live with the permanent PM. Information provided to these patients after a PPI must be substantial as they rely on the healthcare professionals to protect their interests. However, lack of information or misinformation in patients may result in self-imposed restrictions that can adversely affect ordinary day-to-day activities. There is very minimal literature evidence on what PM patients perceive as permissible activities in daily life. The current study findings have brought out the gaps that exist in the patients' knowledge. Conscious effort needs to be taken by nurses to provide appropriate and adequate information on such life-saving devices in order to help patients cope better and experience good QOL.
Financial support and sponsorship
Conflicts of interest
There are no conflicts of interest.
| References|| |
Młynarski R, Włodyka A, Kargul W. Changes in the mental and physical components of the quality of life for patients six months after pacemaker implantation. Cardiol J 2009;16:250-3.
Jackson A. An overview of permanent cardiac pacing. Nurs Stand 2010;25:47-57.
Malm D, Hallberg LR. Patients' experiences of daily living with a pacemaker: A grounded theory study. J Health Psychol 2006;11:787-98.
Dell'Orto S, Valli P, Greco EM. Sensors for rate responsive pacing. Indian Pacing Electrophysiol J 2004;4:137-45.
Kurucová R, Žiaková K, Gurková E, Šimková E. Quality of life of patients with a permanent pacemaker. Cent Eur J Nurs Midwifery 2014;5:15-20.
Poorbahador R, Shad B, Oraii S, Eftekharzadeh M, Mirmasoumi M, Sharif AG, et al
. The national survey of cardiac pacemakers and cardioverter defibrillators. J Tehran Univ Heart Cent 2006;1:95-9.
van Eck JW, van Hemel NM, Kelder JC, van den Bos AA, Taks W, Grobbee DE, et al.
Poor health-related quality of life of patients with indication for chronic cardiac pacemaker therapy. Pacing Clin Electrophysiol 2008;31:480-6.
Uslan DZ, Tleyjeh IM, Baddour LM, Friedman PA, Jenkins SM, St. Sauver JL, et al.
Temporal trends in permanent pacemaker implantation: A population-based study. Am Heart J 2008;155:896-903.
Aqeel M, Shafquat A, Salahuddin N. Pacemaker patients' perception of unsafe activities: A survey. BMC Cardiovasc Disord 2008;8:31.
Nazarian S, Hansford R, Roguin A, Goldsher D, Zviman MM, Lardo AC, et al.
A prospective evaluation of a protocol for magnetic resonance imaging of patients with implanted cardiac devices. Ann Intern Med 2011;155:415-24.
Rassin M, Zilcha L, Gross D. 'A pacemaker in my heart' – Classification of questions asked by pacemaker patients as a basis for intervention. J Clin Nurs 2009;18:56-62.
Hanaa AA, Ebtisam M. Home care for patients with permanent pacemaker insertion. IOSR J Nurs Health Sci 2017;6:49-57.
Udo EO, van Hemel NM, Zuithoff NP, Nijboer H, Taks W, Doevendans PA, et al.
Long term quality-of-life in patients with bradycardia pacemaker implantation. Int J Cardiol 2013;168:2159-63.
van Eck JW, van Hemel NM, van den Bos A, Taks W, Grobbee DE, Moons KG, et al.
Predictors of improved quality of life 1 year after pacemaker implantation. Am Heart J 2008;156:491-7.
Chen HM, Chao YF. Change in quality of life in patients with permanent cardiac pacemakers: A six-month follow-up study. J Nurs Res 2002;10:143-50.
Mitro P, Kotianova A, Bodnar J, Skorodensky M, Valocik G. Quality of life and psychological well-being in patients with various pacing modes. Bratisl Lek Listy 2008;109:260-6.
Benzer W, Oldridge N, Anelli Monti M, Berger T, Hintringer F, Höfer S, et al.
Clinical predictors of health-related quality of life after pacemaker implantation. Wien Klin Wochenschr 2006;118:739-43.
Wang Q, Hay M, Clarke D, Menahem S. Associations between knowledge of disease, depression and anxiety, social support, sense of coherence and optimism with health-related quality of life in an ambulatory sample of adolescents with heart disease. Cardiol Young 2014;24:126-33.
Sossong A. Living with an implantable cardioverter defibrillator: Patient outcomes and the nurse's role. J Cardiovasc Nurs 2007;22:99-104.
Cunha TM, Cota RM, Souza BK, Oliveira BG, Ribeiro AL, Sousa LA. Correlation between functional class and quality of life among cardiac pacemaker users. Braz J Physic Ther 2007;11:341-5.
[Figure 1], [Figure 2], [Figure 3], [Figure 4], [Figure 5], [Figure 6]
[Table 1], [Table 2]