Biopsychosocial Effects of Donor Traits on Heart Transplant Recipients

Abstract

Background

Psychological function after transplantation has garnered increased attention, and the relationship between recipients and corresponding donors has been investigated in medical research. Here, we investigated potential qualitative and quantitative psychological and lifestyle changes among recipients after heart transplantation and their correlation with donors.

Material/Methods

Transplant recipients, their families, and the donor’s families were interviewed. The interview was semi-structured, featuring open-ended questions related to 5 domains: preference, emotions and temperament, memory, self-identity, and social identity. Qualitative data were analyzed by triangulation and deductive content analysis. Quantitative data were collected using the Big Five Inventory-19 (BFI-19) questionnaire, to complement the domain of emotions and temperament.

Results

Overall, 20 recipients, 15 recipients’ families, and 13 corresponding donors’ families were interviewed (5 recipients’ families and 7 donors’ families refused to participate) between October 2020 and July 2021. The data were matched to 13 groups, each including at least 1 recipient and the corresponding donor. Finally, 13 recipients, 9 corresponding recipients’ families, and 13 corresponding donors’ families were identified. Similarities between recipients’ psychological and lifestyle changes and the corresponding donors’ traits were primarily identified in the aspects of diet, emotions and temperament, and special experiences other than dreams. The BFI-19 data showed no significant correlations between recipients and the corresponding donors’ families.

Conclusions

Our findings indicate significant psychological and lifestyle changes in recipients before and after heart transplantation, with 38% exhibiting characteristics partly similar to those of their donors. Further investigation is needed to explore the psychobiological correlation between recipients and donors.

Introduction

Survival after heart transplantation has significantly improved with advancements in immunosuppressive and transplantation techniques [1]. In recent decades, medical care teams have increasingly focused on physiological and psychological functions after transplantation. Extensive investigations have evaluated physical and mental disorders, such as major depression disorder and anxiety [2–4], and occupational adjustment [5,6]. Changes in recipients’ emotions and temperament, memory, interests, professional skills, and gender identity reportedly reflect donor characteristics [7–9].

Pearsall et al interviewed 10 heart transplant recipients and found that each had 2 to 5 characteristics similar to those of their respective donors [7]. Similarly, Mauthner et al reported on 25 transplant recipients, of which 92% (23/25) mentioned changes in self-identity and perception, 36% (9/25) felt that the donor was still alive through the transplanted hearts, and 56% (14/25) mentioned that they had dreamed about or guessed the donor’s appearance [8]. Moreover, Anthony et al studied 27 teenage recipients, most of whom believed that the donor lived through their hearts [9]. Additional etiologies, other than organic causes, such as abnormal serum tacrolimus levels, have been proposed to explain the changes in affective disturbances and elusive delusions observed in heart transplant patients [10]. Liester proposed that donors’ emotions and temperament may be transferred through heart transplantation via cell signaling mechanisms, such as genetic or epigenetic pathways, the intracardiac nervous system, or the electromagnetic energy of the heart [11]. The cell signaling mechanism has been studied in animal models, showing that the sea mollusk Aplysia can acquire the same sensory responses as its trained companions through RNA transfer [12]. Regarding electromagnetic energy, the heart has the largest electromagnetic field in the body, which is 60 times greater than that of the brain [13]. As for the intracardiac nervous system, due to its similarity to the brain [14], it is possible that it plays a role in the storage and transfer of memory or personality. Before further research into potential mechanisms is conducted, the connection between donors’ and recipients’ characteristics through heart transplantation must be established. Such research is important in caring for patients undergoing heart transplantation in the modern era, when quality of life is as important as longevity.

Although heart transplant recipients can undergo psychological and lifestyle changes after transplantation, further investigation is needed to determine the clinical significance of these changes. In this study, we used qualitative and quantitative analysis methods to examine an issue rarely addressed in clinical practice: psychological and life transformation and adjustment in patients after heart transplantation. In addition to cardiac function, mental state is an important factor affecting recipients’ prognosis. Accordingly, we hypothesized that the heart may have the potential to influence emotions, temperament, or memory and that heart transplant recipients might exhibit the donor’s characteristics after transplantation. To test this hypothesis, we included donors’ perspectives from donors’ families to clarify the potential causes of post-transplantation psychological and lifestyle changes in recipients.

Material and Methods

Study Design

This study was approved by the Institutional Review Board of the National Cheng Kung University Medical Center (B-ER-109-234) and adhered to the International Society for Heart and Lung Transplantation statement on transplant ethics [15]. Data triangulations were used to verify the hypothesis [16]. Data from recipients, recipients’ family members, and donors’ family members were collected through comprehensive interviews. In the study, the qualitative method was primarily used, whereas the quantitative method with questionnaires complemented the qualitative result. We used a “convergent design” to collect qualitative and quantitative data simultaneously, which were then merged during the analysis phase. The qualitative data were analyzed using content analysis.

Materials

Using data from the National Cheng Kung University Hospital (NCKUH) database from 2005 to 2020, we prospectively recruited and interviewed the heart transplant recipients, their families, and donors’ families, and collected clinical background data on the recipients and donors.

First, the deceased recipients were excluded. Second, for better access, we preferentially recruited recipients and their corresponding donors’ families. The corresponding donors had undergone surgery at NCKUH or nearby hospitals (in Tainan or Kaohsiung City). We recruited recipients and their families first; if the recipients consented to an interview, the corresponding donors’ families were contacted to participate.

By phone call, we recruited recipients who were sufficiently healthy and able to understand and communicate, obtaining their verbal consent first. Afterward, we obtained formal written consent and conducted the interview in person. For the recipients’ family members, the same recruiting process was followed. For the corresponding donors’ families, we contacted the family members listed in the contact information and recruited those who verbally consented to an interview first. Subsequently, we obtained formal written consent and conducted the interview in person.

Data Collection of Qualitative Data

The concept of “phenomenology of perception”, proposed by Merleau-Ponty and describing how human experience or identity may change through modifying or transferring the body was used to guide the interview process in this study [17].

The interview was primarily conducted by CCH under the supervision of professional researchers YYH and JNR, who specialize in quantitative and qualitative analysis. Before the study, relationships were established between the interviewer and participants by the transplant case manager and the social workers. Participants were informed about the study’s objectives and procedures and the interviewer’s background via telephone before the interviews.

The interview was semi-structured, featuring open-ended questions, and included 5 domains: preference, emotions and temperament, memory, self-identity, and social identity. The domain of preference was categorized into 6 aspects: diet, color, clothes, people/objects/events, music, and sex. The domain of memory was classified into 3 aspects: special experiences related to dreams, special experiences other than dreams, and impressions on donors. The 5 domains were chosen based on the review article [11]. For recipients, all 5 domains were asked; for recipients’ family members, all domains except self-identity were covered in the interview; for donors’ family members, the first 3 domains – preference, emotions and temperament, and memory – were covered in the interview. The questions were adjusted individually for recipients, recipients’ family members, and donors’ family members.

Interview locations included clinical rooms, quiet public spaces in the hospital, patients’ homes, and quiet public spaces near the patients’ residences. The interviews were recorded after informed consent was obtained from the respondents, and field notes were also taken. In cases in which the respondents did not agree to be recorded, the interviews were transcribed verbatim by hand and converted into electronic records within 48 h after completion. Each interview lasted 20 to 30 min. No repeat interviews were conducted, and the transcripts were not returned to the interviewees.

Data Collection of Quantitative Data

Quantitative data were collected to complement the domain of “emotions and temperament” using the Big Five Inventory-19 (BFI-19) questionnaire, which was verified for reliability [18]. The original version was BFI-44, created by John et al [19]. The Neuroticism-Extraversion-Openness Five-Factor Inventory scale, similar to the BFI-44, has been used in heart transplantation studies [20,21]. The BFI-19 questionnaire consists of 5 parts: extraversion, agreeableness, conscientiousness, openness, and neuroticism. It comprises 19 questions rated on a 5-point scale, ranging from 5 (strongly agree) to 1 (strongly disagree) for each question (Table 1).

Table 1.

Big Five Inventory-19 (BFI-19).

I see myself as someone who…	Disagree strongly	Disagree a little	Neither agree nor disagree	Agree a little	Agree strongly
01. Is talkative
02. Is full of energy
03. Generates a lot of enthusiasm
04. Is outgoing, sociable
05. Is helpful and unselfish with others
06. Has a forgiving nature
07. Is considerate and kind to almost everyone
08. Likes to cooperate with others
09. Is generally trusting
10. Perseveres until the task is finished
11. Does things efficiently
12. Makes plans and follows through with them
13. Is original, comes up with new ideas
14. Has an active imagination
15. Is inventive
16. Likes to reflect, play with ideas
17. Can be tense
18. Worries a lot
19. Gets nervous easily

Recipients and their families were requested to report the recipients’ status before and after transplants using the BFI-19 (recipients and their families completed 2 BFI-19 questionnaires, respectively). The donor’s families provided the information based on their knowledge of the donors. The survey took 10 to 15 min.

Data Analysis of Qualitative Data

In this study, we used a deductive research approach and used content analysis [22] to validate the hypothesis by examining interview data. The researcher first converted the audio files of the interview into verbatim digital records listing key questions, whereas handwritten verbatim transcripts were converted within 48 h after the interviews. The content analysis was conducted as follows: First, the answers to each question were summarized and assessed for recipients and their families to determine whether changes arose in each aspect. Second, for donors’ families, the answers to each core question were summarized. Third, the recipients’ and their families’ expressions of these changes (including tone, wording, and recipients’ interpretations of their changes) were analyzed and compared with how the corresponding donors were described by their families. Any changes similar to the traits of the corresponding donors were recorded and further discussed with the other members of the research team.

Data Analysis of Quantitative Data

For the BFI-19 questionnaire, the Wilcoxon signed-rank test (Python 3.12.4 version) was used to test for significant differences within 2 categories, defined as follows: The first was “recipients’ perceptions of themselves before transplantation vs recipients’ perceptions of themselves after transplantation”. The second was “perceptions of recipients’ families about recipients before transplantation vs perceptions of recipients’ families about recipients after transplantation”. Additionally, the Spearman rank correlation (SPSS software version 25; IBM Corp, Armonk, NY, USA) was used to test for positive correlation in 2 categories, defined as follows: The first was “recipients’ perceptions of themselves after transplantation vs perceptions of donor’s families about the donors”. The second was “perceptions of recipients’ families about recipients after transplantation vs perceptions of donor’s families about the donors.” Statistical significance was set at P<0.05.

Results

Finally, 48 people were interviewed between October 2020 and July 2021, including 20 recipients, 15 recipients’ family members, and 13 donors’ family members. During the interview, 2 recipients were excluded due to insufficient communication and understanding caused by dementia and stroke. The data were matched for at least 1 recipient and the corresponding donor to test for the hypothesis. Finally, 13 groups, including 13 recipients, 9 recipients’ family members, and 13 corresponding donors’ family members, were matched for analysis (Figure 1). During the interviews, certain similar responses were identified among the interviewees. Previous studies indicate that a sample size of approximately 9 to 17 interviewees can achieve significant data saturation in a focused research topic [23]. In light of this, we decided to finalize the study after interviewing 13 groups of participants.

Figure 1.

Flowchart of the case recruitment and analysis. Recipients’ families included their parents, spouses, sons, or daughters. Donors’ families included their parents, spouses, brothers, or sisters. (Microsoft Office LTSC PowerPoint 2021).

The average age of the 13 recipients was 48.5 years (range: 35–65) at the time of transplantation and 56.1 years (range: 40–75) at the time of the interview. The mean interval from transplantation to the interview was 7.6 years (range: 2 months to 14 years). The background data of the interviewees are presented in Table 2.

Table 2.

Summary of donor and recipient cases.

Donor					Recipient
Case	Age	Sex	Cause of death	Family member	Age	Sex	Diagnosis	Post-OP (y)	Family member
1	17	F	Suicide by jumping off a building	Mom	56	M	DCM	13.9	Wife
2	47	M	Pedestrian hit by car	Brother	38	M	DCM	13.3	Mom
3	46	F	Encephalopathy	Parents	40	M	DCM	13	–
4	55	F	Charcoal-burning suicide	Brother	65	F	DCM	12.3	Sister
5	24	F	Scooter hit by car	Parents	37	F	DCM	11	Daughter
6	49	F	Scooter hit by car	Husband	63	M	ICM	7.5	Wife
7	43	M	Brain abscess	Sister	44	M	DCM	6.5	Wife
8	20	M	Scooter hit by car	Sister	44	M	DCM	5.8	–
9	18	M	Scooter accident	Father	61	M	DCM	5.5	Son
10	36	M	Areca catechu poisoning	Wife & son	35	M	ICM	4.5	–
11	71	M	Pedestrian hit by car	Wife	51	M	ICM	2.3	Wife
12	23	M	Scooter hit by car	Mom	48	F	DCM	2.5	–
13	45	F	Spontaneous ICH	Brother	49	M	DCM	0.3	Mom

ICH – intracranial hemorrhage; DCM – dilated cardiomyopathy; ICM – ischemic cardiomyopathy; Post-OP (y) – post-operation (heart transplant) year = date of interview – date of transplant; recipient age – age at transplantation.

Summary of Conformities or Similarities Between Recipients’ Changes and the Traits of Corresponding Donors

For 3 main domains – preference, emotions and temperament, and memory – recipients’ change in each domain was compared with the traits of corresponding donors. For individual cases, 5 recipients (5/13, 38%) had 2 or more similar or conforming aspects with their corresponding donors (Table 3). Among all aspects, diet had the most conformities or similarities. The statistics of the other aspects are shown in Figure 2. The highlights of some aspects are shown as follows, and a summary of the important content is presented in Table 3.

Table 3.

Summary of conformities or similarities between recipients’ changes and the traits of their corresponding donors.

Case	Content	Total amount
Case 1	No recorded conformities	0
Case 2	No recorded conformities	0
Case 3	No recorded conformities	0
Case 4	Rejects certain foods	1
Case 5	Fonder of gray and white More gentle and thoughtful Not personally experienced dream Feel excited for no reason as coming back for the regular check-up Hear a young girl’s voice	4
Case 6	No recorded conformities	0
Case 7	Constantly felt as if something had dropped	1
Case 8	More “civilized,” equable and patient Dreams about being chased, rolling down from the top of the mountain, killed by a car	2
Case 9	Preference for spicy food	1
Case 10	Better temper, more thoughtful and observant Increased sensitivity to supernatural events If no regularly worship for the memorial tablet, I wound be admitted for severe sickness	3
Case 11	Blander diet, decreased capacity for eating without hungry Easier touched by movies or news Better at observing people	2
Case 12	Lower tolerance for spicy food Accidentally watched TV interview program, which the donor’s mother participated in	2
Case 13	No recorded conformities	0

Figure 2.

Conformities or similarities between recipients’ changes and the traits of their corresponding donors. Thirteen groups, including at least recipients and their corresponding donors’ families, were analyzed. Detailed descriptions can be found in the results (Microsoft Office LTSC PowerPoint 2021, Excel 2021).

Preferences in Diet

Four groups of interviewees (cases 4, 9, 11, and 12) mentioned conforming or similar content in diet, specifically noting taste preference, such as a preference for spicy food, and food intake, such as a decreased amount of intake without hunger. The recipient in case 11 stated, “After the transplantation, my appetite seems to have decreased to about one-third. However, even though I eat less, I do not get hungry easily. I think such dietary habits may also be affected by the donor.” The recipient’s family said, “He does not make a special effort to refrain from eating. He simply started eating less naturally.” The donor’s family remarked, “My husband did not eat much, approximately 80% of a bowl of rice each meal, roughly the same as other men his age. He had a healthy appetite but ate at a slow pace.”

Emotions and Temperament

Three groups of interviewees (cases 5, 8, and 10) mentioned conforming or similar content related to emotions and temperament. Changes in positive emotions and temperament, such as being more patient or thoughtful, were reported. In case 10, the recipient stated, “I flew into a rage constantly before, but I have changed a lot after the transplantation. I think this change occurred naturally; I did not even notice it initially until others reminded me. I think perhaps it has something to do with the donor. Perhaps the donor was a kind-hearted, sweet-tempered person. Besides, I have become more thoughtful and perceptive of others’ personalities and characters. Personally, I think the donor must be the principal reason for these changes because I did not behave like this before!” The donor’s family remarked, “He was quiet, reticent, contemplative, and gracious. He did not talk much about himself. He was not argumentative and undertook what he did out of the kindness of his heart.”

For the complementary quantitative data from the BFI-19 questionnaires, 1 donor’s family (case 1) and 1 recipient’s family (case 13) were excluded due to missing data. Finally, 12 groups related to recipients or donors and 7 groups related to recipients’ families or donors were analyzed. The analysis showed no significant difference in the 5 parts between the status before and after the transplant and no significant positive correlation between the status after the transplant and the donors’ information (Table 4).

Table 4.

Statistical analysis of the Big Five Inventory-19 (BFI-19) among different combinations.

BFI-19 subsets/group	Wilcoxon signed rank test			Spearman rank order correlation
		Rba(12)*	RFba(7)**		RaDF(12)*	RFaDF(7)**
Extroversion	Statistic	9.0	5.0	CC	−0.46	0.286
	P	0.395	0.246	P	0.123	0.491
Agreeableness	Statistic	7.5	4.0	CC	0.102	−0.606
	P	0.269	0.715	P	0.733	0.121
Conscientiousness	Statistic	9.5	2.0	CC	−0.25	0.434
	P	0.833	0.138	P	0.415	0.297
Openness to experience	Statistic	18.5	1.5	CC	−0.374	0.218
	P	0.633	0.414	P	0.224	0.602
Neuroticism	Statistic	8.0	0	CC	0.089	−0.434
	P	0.596	0.102	P	0.766	0.297

Rba – recipients’ perceptions of themselves before transplantation vs recipients’ perceptions of themselves after transplantation; RaDF – recipients’ perceptions of themselves after transplantation vs perceptions of donor’s families about the donors; RFba – perceptions of recipients’ families about recipients before transplantation vs perceptions of recipients’ families about recipients after transplantation; RFaDF – perceptions of recipients’ families about recipients after transplantation vs Perceptions of donor’s families about the donors; CC – correlation coefficient; P – p value. Bracket: the amount of the groups;

^*The donors’ family in case 1 with missing data >20% was thus excluded;

^**The recipients’ family in case 13 with missing data >20% was thus excluded.

Memory: Special Experiences Other than Dreams

Three groups of interviewees (cases 5, 7, and 10) mentioned conforming or similar content related to special experiences other than dreams. Certain inexplicable experiences were noted. In case 5, the recipient stated, “Every time I come back for a check-up, I feel excited for no reason. Despite being nervous, I feel inexplicably cheerful. In addition, during the first 2 years after the transplantation, I would hear someone talking to me. It was a young girl’s voice calling my name in a soft tone.” The donor’s family said, “My daughter was a nurse. She liked being with older people. She was responsible, conscientious, and dedicated to her work. She often worked overtime till late at night.”

Other Aspects

Regarding special experiences related to dreams, 2 groups of interviewees (cases 5 and 8) mentioned conforming or similar content. The dream content was associated with important life events in the donors’ lives, such as death or accident (case 8). Concerning memory-impression on donors, 2 groups of interviewees mentioned conforming or similar content. The impression was connected to the donor’s characteristics (case 10) or the donor’s family’s wishes (case 12). Regarding preference-color and preferences for people, events, and objects, 1 group of interviewees mentioned conforming or similar content in each aspect (cases 5 and 11, respectively).

Changes in Self-Identity or Social Identity Reported by Recipients and Their Families

Regarding domains of self-identity and social identity, neither the recipients nor their family members felt a change in their identity themselves. However, regarding the identity of the new heart, 3 recipients were not accustomed to their new hearts and expressed strong feelings that these were not their organs (cases 9, 11, and 12).

Discussion

To the best of our knowledge, few studies on psychological changes in heart transplant recipients have included donors’ information. Hence, this study focused on recipients and their families as well as donors’ families for a more accurate assessment. This is the first study in Asia investigating changes in the characteristics of heart transplant recipients after transplantation and the correlation with corresponding donors. The results revealed changes in food preferences, emotions and temperament, and memories of recipients after heart transplantation, with a certain level of association with their corresponding donors.

Not all of the psychological and lifestyle changes mentioned by the 13 recipients were similar or identical to the donor’s traits. Some may have been influenced in part by the donors while still being deliberate adjustments made by the recipients for specific reasons, such as adhering to a bland diet or adopting a gentler demeanor, whereas other changes had no specific cause and did not align with the traits of the respective donors. Bunzel et al reported similar findings, in which 6% (3/47) of the recipients reported significant post-transplantation personality changes, which they attributed to their new hearts. These recipients presented new behaviors postoperatively, whereas 94% (44/47) of the other recipients did not report such correlated changes [24].

Among the 13 recipients in the present study, the aspect with the highest similarity or conformity was diet, followed by emotions and temperament, special experiences other than dreams, and special experiences related to dreams. Similar findings were reported by Pearsall et al, who found that, regarding diet, changes to vegetarianism or significant decreases in the amount of food intake were reported. For special experiences related to dreams, a recipient experienced a flash of light in the face during a dream; the recipient had received a heart from a police officer who died from a gunshot [7].

Beyond the potential impact on daily life from donors, other factors might contribute to psychological and lifestyle changes in recipients. In terms of diet, long-term consumption of bland diets by the recipients during hospitalization can cause changes in taste [25,26]. Additionally, medications, such as tacrolimus, can cause hypogeusia [27]. Calcineurin inhibitors or steroids can cause dry mouth, decreased saliva secretion, and susceptibility to tooth decay, all of which can affect taste [28,29]. Changes in emotions and temperament may be explained by the significant psychological impact experienced during heart failure admissions before heart transplantation [30]. Also, Evangelista et al reported that heart transplant recipients had self-transcendent thoughts, allowing them to realize and treasure the value and meaning of life, thereby affecting behavioral changes [31]. Concerning special experiences other than dreams, some environmental factors, including anticipation when seeing the medical team during follow-up visits, or individual factors, including imagination or speculation about the donor, might be considered. Concerning special experiences related to dreams, the recipient’s inexplicable dream content might also be explained by delirium in the Intensive Care Unit. Roberts et al reported that a high proportion of patients in the Intensive Care Unit with delirium also have confused dreams [32]. Although these factors should be considered, they fail to fully address the psychological and lifestyle changes of the recipients in our study.

During the quantitative investigation using BFI-19 questionnaires to assess and complement the emotions and temperament aspect, we did not observe any significant correlations between the results of the donors’ family members and those of recipients or their families. However, the interview results exhibited inconsistency, with 3 out of 13 recipients (cases 5, 8, and 10) describing changes in the emotions and temperament aspect during the interactive investigation. Two possible reasons may partially account for the inconsistency. First, the number of cases with emotional and temperament change (3 cases) and the total number of cases (13 groups) were too small to show significant findings. Second, the questionnaire may incomprehensively cover the potential emotional and temperament items and responses experienced by the interviewees. Overall, the changes mentioned in the interview still warrant further investigation.

Regarding aspects of self-identity and social identity, 3 recipients were not accustomed to their new hearts. These findings were consistent with previous studies. Mauthner et al and Anthony et al both mentioned identity-related changes, reporting that participants felt “the donor still lives through their hearts” [8,9].

Moreover, we found that interviewees’ attitudes toward heart transplantation and their sociocultural backgrounds can affect the collection of information. In the present study, the recipient in case 13 was passive during the interview and held the concept that the heart is just a pump. However, the recipient in case 5 was active and curious, having searched this issue just after transplantation. The recipient in case 13 participated less in discussion and responded less frequently than did the recipient in case 5.

Sanner investigated the effects of these factors on subjective interpretation [33,34]. Anthony et al found that the perception of the medical team and attention to psychological aspects after transplantation can influence recipients’ interpretation and expression [9]. Additionally, Mai found that many heart transplant recipients adopt a “denial” attitude toward the new heart and donors, which is a process of adaptive integration [35]. Furthermore, a paper published in the Journal of Heart and Lung Transplantation in 2010 showed that 52% of patients exhibited a disjunction between their words and embodied expressions, suggesting that recipients may experience hidden emotions of distress [3].

These conceptual differences can affect how these recipients interpret their physical, emotional, and temperament changes, their perceptions of the new heart and donors, and the information they provide.

Limitations

This study had some limitations. First, the investigators were primarily responsible for determining whether the characteristics of both parties were similar or identical, which could be influenced by the investigator’s awareness and background knowledge. Second, due to the small sample size, extrapolation of our study findings should be approached with caution. Third, the donors in this study were represented by their family members, which may not reflect the actual condition of the donors. Fourth, recipients were interviewed after transplantation, which can introduce recall bias. Fifth, the duration from transplant to interview varied among recipients, and different post-transplant stages may have affected their perception of bodily changes and interpretation of characteristic changes. Sixth, the different attitudes toward heart transplantation and diverse sociocultural backgrounds may have influenced the data collection. Seventh, the study primarily relied on qualitative data, with quantitative data limited to the aspect of emotions and temperament. The limited quantity of quantitative data can affect the objectivity of the research. To achieve better results in the future, increasing the number of interviewers with different backgrounds, recruiting more family members or friends of donors, or using a prospective study to follow up with the recipients before and after heart transplants may be considered, to overcome limitations.

Conclusions

Our study revealed a few similarities in lifestyle between heart transplantation recipients after transplant and their corresponding donors, with 38% (5/13) of transplantation recipients having 2 or more similar or conforming aspects. We found changes in recipients’ preferences, emotions and temperament, and memories after transplantation, with a certain level of correlation with their corresponding donors. Identifying these characteristics might improve self-care ability and reduce life stress after transplantation. The mechanisms explaining these similarities require further investigation, and more rigorous, larger-scale clinical studies are required to further validate the correlations. In the future, we recommend first conducting a prospective study that traces patients from pre-transplant to post-transplant status to obtain more accurate interview information and avoid recall bias. Second, future research should incorporate more quantitative methods to complement qualitative research, thereby enhancing the credibility of the analysis. Third, in terms of basic research, the intracardiac nervous system and cellular memory warrant further studies to verify their potential in transferring individual characteristics. Our findings encourage clinicians to provide more comprehensive information during the preoperative informed consent and postoperative psychological evaluations, to provide recipients with more holistic care and an improved quality of life after heart transplantation.