Perioperative Psychological Interventions in Heart Surgery
Opportunities and Clinical Benefit
Background: Heart surgery is a source of high levels of emotional distress for the patient. If the stress experience is not adequately compensated, it can have a negative impact on postoperative recovery, as can untreated comorbid mental disorders.
Methods: A selective literature review on emotional distress and mental comorbidities in heart surgery patients and a scoping review on the spectrum and effectiveness of perioperative psychological interventions to compensate and reduce the stress experience.
Results: Mental factors such as depressive symptoms or anxiety disorders are associated with an elevated risk of postoperative morbidity and mortality in patients treated for heart disease. Mental comorbidities occur more frequently in these patients than in the general population. Following the manifestation of chronic heart disease (CHD), for example, 15–20% of the patients display severe depressive disorders. A few psychotherapeutic interventions to reduce anxiety and depression, emotional distress, consumption of analgesics, and extubation time have been found effective, with low to moderate evidence quality. Many different psychological interventions have proved useful in clinical practice, including multimodal, multiprofessional interventions incorporating medications, education, sports, and exercise as well as psychosocial therapy including stress management. Individual psychotherapy during the period of acute inpatient treatment after myocardial infarction is also effective.
Conclusion: Because psychosocial factors are important, the current guidelines recommend systematic screening for mental symptoms and comorbidities in advance of heart transplantation or the implantation of ventricular assist devices (VAD). Acute psychotherapeutic interventions to reduce mental symptoms can be offered in the perioperative setting.
For patients undergoing heart surgery, the operation is associated not only with the hope of recovery from illness and an improved quality of life, but also with considerable mental stress. Heart surgery is often interpreted as an extraordinary and life-threatening event even before it takes place, and is then experienced as such. The feeling of having little or no control over the situation is a further central stress-inducing factor for many patients.
Anxiety manifestations, anxiety disorders, post-traumatic stress disorder, postoperative delirium, acute adaptive disorder, and stress-induced worsening of cardiovascular parameters are common. When patients are unable to cope with the stress that they experience, this can lead to mental stress reactions, which, in their further course, can adversely affect physiological and mental parameters that have an impact on the recovery from illness and surgery. Psychological support in heart surgery is most commonly needed by patients undergoing heart transplantation or the implantation of a ventricular assist device (VAD). These patients have the longest hospital stay of all heart surgery patients; moreover, the mental stress of receiving a new heart or a visible machine implanted in the heart has been described as being extremely high. The risk of complications after heart surgery is additionally increased if the patient has a psychiatric comorbidity. Studies have been performed to determine whether psychological preparation and perioperative psychological treatment can positively affect the postoperative course. This review is concerned with two main questions:
- What types of mental stress and comorbidity are most common in heart surgery patients?
- What psychological interventions are used pre- and postoperatively in cardiac surgery to compensate for the stress that patients experience and to lessen the acute adverse mental and physical effects of psychiatric comorbidities, and how successful are they?
In what follows, we will first discuss the prevalence of psychological stressors and disorders in various groups of patients undergoing heart surgery. Then, we will present the findings of a scoping review relating to the second main question above. A scoping review is intended to be systematic, but also exploratory; its goal is to reveal the extent of the available literature on a given question, including the important terms and concepts, evidence sources, and evidence gaps.
Mental comorbidities in heart surgery
Mental comorbidities and mental stresses in heart surgery patients differ in their incidence, prevalence, and postoperative effects, depending on the indication for surgery. For all indications taken together, a 10% to 50% incidence of postoperative delirium after heart surgery has been observed (1).
Coronary heart disease and bypass surgery
Correlations between mental factors and the development and course of cardiovascular diseases have been repeatedly observed (2, 3). Definitively identified risk factors for the maintenance of coronary heart disease (CHD) include changes in the endocrine system and inflammatory processes as a psychobiological mechanism (4), as well as unfavorable health-related behavior. After clinically overt CHD, 20-50% of patients show depressive manifestations, and 15-20% have severe depressive disorders (5). Approximately 12% of patients who have had a myocardial infarction go on to develop the full syndrome of a post-traumatic stress disorder (PTSD) (6). Anxiety disorders are also associated with a worse prognosis after an infarction (hazard ratio 1.94) (7).
Thus, the evidence indicates that CHD patients are exposed to a higher risk of mental comorbidities, and that these, in turn, can exert a negative effect on the outcome of CHD. In routine clinical practice, it is generally observed that the mental stress associated with a bypass operation is greatest before surgery and rapidly diminishes thereafter. The association between preoperative depression and higher postoperative morbidity and mortality has been reported multiple times (8). A significant degree of preoperative anxiety in a bypass patient is associated with an elevated risk of postoperative atrial fibrillation, acute myocardial infarction, rehospitalization, and elevated morbidity and mortality (9).
Postoperative cerebral dysfunction (POCD) persists for 6-12 months or more in 20–40% of bypass patients; this is a serious complication, particularly for elderly patients (10). A complex interaction of cerebral embolism, hypoperfusion, inflammation, underlying cerebrovascular disease, and elevated preoperative stress is considered to be the basis of, and a risk factor for, the development of POCD (10).
Valvular diseases and valve surgery
The percentage of patients with elevated values on the Hospital Anxiety and Depression Scale before a mitral valve operation (33%) and shortly thereafter (28%) is high compared to the general population (20%). These differences level off by six months after surgery (11). Surprisingly, patients who have undergone the implantation of a mechanical aortic valve prosthesis have been reported to have higher anxiety and depression scores than patients who have received a heart transplant (12).
Cardiac arrhythmias, rhythm surgery, heart failure, the implantation of cardiac support systems, and heart transplantation
Most studies of the psychosocial aspects of rhythm surgery have investigated patients with an implantable cardioverter/defibrillator (ICD). The prevalence of mental disorders after ICD activation is 11–28% for depression, 11–26% for anxiety disorders, and ca. 25% for PTSD (13). Comorbid depression appears to be a significant predictor of a larger number of ICD shocks and of increased overall mortality (14).
At present, there are no reliable data on the prevalence of mental disorders in patients who have undergone VAD implantation. In an initial assessment, 64% of patients with a cardiac support system were found to carry at least one psychological or psychiatric diagnosis requiring treatment (15). Patients seem to develop new anxieties over the long term, and the depressive tendency rises with time (16). Alarms and faulty technical equipment can lead to stress reactions, sleep disturbances, and impairment of the ability to carry out everyday activities (17). Patients should be encouraged to emotionally accept their dependence on a visible device attached to their heart and to cope with their anxieties relating to device malfunctions and complications (18). Patients are particularly afraid of complications leading to cognitive impairment, e.g., intracranial hemorrhage or stroke (19).
A recent review (20) clearly shows that the presence of depression is associated with an elevated relative risk of dying after heart transplantation (RR 1.65). The prevalence of PTSD after heart transplantation is approximately 10% (21).
Patients describe the most severe symptoms and the lowest subjective quality of life during the time that they are waiting for a donor heart. Moreover, depression is associated with increased mortality on the waiting list (22). Patients state that the main stressors are the perception of their own diminishing performance, the fear of not surviving the time on the waiting list, the uncertain timing of transplantation, fear of the donor organ, and fear of organ rejection and death.
Psychological acute interventions for heart surgery patients
The following sections will consist of a scoping review on the second main question asked at the beginning of this article. Following Ziehm et al. (23), we searched for studies of interventions that were carried out in the hospital and that are based on established psychological theories of behavior and behavioral change. These interventions should relate to identifiable components of treatment and specifically address the mental distress caused by surgery as well as the patient’s negative attitudes and noncompliance, with the goal of improving postoperative recovery up to the time of hospital discharge.
A search was carried out in the PubMed and Psycinfo databases, employing the following terms: psych*, mental, heart, cardi*, intervention, therapy, treatment, hospital, *operative, surgery, and operation. Empirical peer-reviewed studies, guidelines, meta-analyses, and systematic reviews concerning adult patients and written in either English or German were selected. Five relevant publications were found in this way, and a further 14 were identified in the reference lists of the original five publications and by searching Google Scholar. Two general guidelines were considered as well.
The findings of this review are presented below in three steps. First, the recommendations of the con-sensus-based guidelines for basic psychosomatic care are described. The following section deals with the measured effects of acute interventions. Finally, an unsystematic overview is given of the many types of concrete intervention that have been described in the pertinent guidelines and studies.
Guidelines on in-hospital psychosomatic care
Most heart surgery patients had heart disease long before being hospitalized. There are recommendations on basic psychological and psychosomatic care for the long-term treatment of mental comorbidities in patients with chronic heart disease (6). These guidelines only rarely contain further specific treatment recommendations for patients who will undergo heart surgery. Psychocardiological care in the acute hospital setting should have the following main objectives: diagnosis, communication, the differential determination of indications for treatment, and assessment of the significance of individual risks (6). Accordingly, the following interventions are recommended, particularly for patients who display the risk factors described above, both for patients with chronic heart disease in general and, specifically, for hospitalized patients about to undergo heart surgery:
- Interdisciplinary basic psychosomatic care should be provided to all patients (6, 24).
- As a rule, multimodal and multiprofessional interventions (drugs, education, sports, and exercise, as well as psychosocial therapy, including stress management) are recommended. In particular, individual psychotherapy during acute hospitalization for myocardial infarction has been found effective (6).
- Relaxation techniques should be offered to patients with arterial hypertension (6).
- Persons with mental comorbidities should continue to receive psychotherapy and psychoactive medication, along with appropriate care of their cardiac and other diseases (6).
Meta-analyses of the efficacy of psychological acute interventions
The Table contains an overview of the effects of perioperative psychological acute interventions on various outcome measures before hospital discharge, as assessed in pertinent meta-analyses. The meta-analyses mostly revealed effects that were not statistically significant, which will not be mentioned in this article for reasons of space. Nor will there be any mention of effects that can be demonstrated only after the patient is discharged from the hospital, e.g., treatment adherence or manifestations of chronic mental illness.
Three meta-analyses deal exclusively with heart surgery (23, 24, 25, 26). A further three meta-analyses (27, 28, 29) include heart surgery as a component of a wider investigation; the effect strengths reported in these meta-analyses are thus largely based on studies of patients who were not undergoing heart surgery.
Recent meta-analyses (23, 25) on the specific effects of psychological interventions have shown, on the basis of low- to medium-quality evidence, that psychotherapeutic interventions in heart surgery patients can effectively lessen anxiety and depression, mental distress, analgesic use, and the time to extubation. No effect on any other outcome could be confirmed by the meta-analyses, whose informativeness was limited by the relatively low quality and small number of the included studies.
A multiplicity of specific acute interventions
Ten of the included studies included descriptions of specific perioperative psychological acute interventions for heart surgery patients (6, 18, 23, 28, 29, 30, 31, 32, 33, 34). These are summarized in Box 1, where the following specific manifestations are mentioned as the targets of psychological acute interventions, along with their negative effects: anxiety, anxiety disorders, tension, worry, excessive preoperative mental stress, stress reactions during surgery, pain, pain experience, excessive analgesic consumption, delayed mobilization, metabolic disturbances, and emotional stress, particularly in heart transplant patients. Tefikow et al. (29) provide a narrative review with information about the goals, methods, and timing of psychological interventions for surgery in general. Psychotherapeutically guided patient-centered communication comprises a multiplicity of therapeutic approaches and individual interventions that can be implemented at any time during the patient’s hospital stay. These are summarized in Box 2.
In many situations, heart surgery patients can benefit from psychopharmacoptherapy in addition to targeted psychotherapy.
Benzodiazepines are potent, rapidly acting, and generally well-tolerated drugs. They are particularly suitable for crisis intervention. Their well-known side effects include respiratory depression at high doses, potential habituation, and, particularly in elderly patients, paradoxical reactions with agitation and hallucinations.
Short-acting substances without active metabolites should be used as a rule. Lorazepam meets these criteria well and has a marked anxiolytic effect; it can be given either intravenously or by mouth. Opipramol, a tricyclic piperazinyl derivative, also has a good anxiolytic effect, without inducing dependency. Pregabalin is a centrally active calcium-channel blocker; used for long-term therapy, it has a very good anxiolytic effect, with few drug interactions or side effects. Benzodiazepines can be useful as a short-term intervention, while opipramol and pregabalin are more suitable for the long-term treatment of anxiety syndromes.
The available drugs for depressive disorders include tri- and tetracyclic antidepressants and the selective serotonin or norepinephrine reuptake inhibitors (SSRI/SNRI). The main cardiac side effect of the tricyclic antidepressants is slowing of intracardiac conduction (atrioventricular conduction in the bundle of His; further conduction in the Purkinje fibers). They can also prolong the QT interval as corrected for heart rate (QTc), potentially inducing a clinically relevant arrhythmia, particularly when these drugs are given in combination with other drugs that are problematic in this respect. The anticholinergic effects of tricyclic antidepressants include dry mouth, accommodation disturbance, micturition disturbances, and, most seriously from the clinical point of view, a delirogenic component. For these reasons, tricyclic antidepressants should not be given to patients with heart disease. SSRI/SNRI are the preferred alternatives, with much rarer side effects, and venlafaxine is good in this respect as well. The central serotonergic syndrome, consisting of fever, qualitative/quantitative impairment of consciousness, tachycardia, hypertension, and other manifestations, is a rare but clinically significant side effect of SSRI. This is generally an acute problem, but it can also take a protracted course, particularly in elderly patients.
Post-traumatic stress disorder
Sertraline, paroxetine, and venlafaxine can be used to treat PTSD.
Delirium is, by definition, an acute organic psychosis, and is thus a neuropsychiatric emergency. Its treatment is symptom-oriented, consisting mainly of the administration of low- and high-potency neuroleptic drugs, and sometimes benzodiazepines. The low-potency neuroleptic drugs (melperone, pipamperone, and others) are used mainly because they are sedating but do not depress respiration; their antipsychotic effect is weaker. Among the high-potency neuroleptic drugs, the ones mainly used at present are the so-called atypical substances, including quetiapine, risperidone, and olanzapine, which carry a much lower risk of extrapyramidal side effects than the traditional high-potency neuroleptic drugs, such as haloperidol. All drugs of this class prolong the QTc interval. The risk of a ventricular arrhythmia or sudden cardiac death depends on genetic factors, pre-existing heart disease, the dose of the neuroleptic drug used, and the drugs that the patient is taking concomitantly, if any.
When a patient who is about to have heart surgery is also suffering from a mental disorder, concomitant psychotherapy should be offered. In view of the important role played by psychosocial factors, any patient for whom heart transplantation or the implantation of a VAD is planned should undergo systematic screening (24, 35). Current evidence indicates that a number of psychotherapeutic interventions are effective in alleviating mental disturbances.
It has been found useful in clinical practice to encourage patients who are about to undergo surgery to accept their own anxiety about the operation, rather than repress it out of shame; to formulate very concrete, individual goals for the time after the operation; to consider how they might reward themselves for meeting the challenges they are currently facing; to be aware of the social support that is available in the current crisis situation of heart surgery; to imagine a space of inner tranquility and serenity (a “safe place”); and to imagine their own emotional ease and relief once the operation is past (18).
A review showed that depression and anxiety in the setting of heart surgery can be more effectively reduced by interventions that last longer than a single discussion and that are carried out personally by an experienced psychologist in a one-on-one setting (6, 23). Under these conditions, bypass patients had reduced depression and ICD patients had reduced anxiety.
In psychological interventions after heart surgery, it is especially important for patients to be able to express their feelings through the verbalization of emotional experiences (VEE). Moreover, resource- and future-oriented interventions are used, in which the previously formulated goals for recovery are recalled by the patient and then implemented in manageable steps. Relaxation techniques (autogenic training, autohypnosis, and progressive muscle relaxation, suitably adapted to the somatic situation) are also used. Hypnotherapeutic interventions are very effective for the reduction of anxiety, pain, emotional stress, and emotional distress. After heart transplantation, special attention must be paid to organ integration; after VAD implantation, emphasis is placed on the patient’s altered body image (caused by the driveline and the battery/controller pouch).
In conclusion, even though psychotherapy for heart surgery patients is not currently reimbursed by health insurance in Germany, integrating a psychologist in the cardiac surgical team is clearly advisable.
Conflict of interest statement
The authors declare that no conflict of interest exists.
Manuscript received on 14 September 2020, revised version accepted on 17 December 2020.
Translated from the original German by Ethan Taub, M.D.
Dr. phil. Katharina Tigges-Limmer, Dipl.-Psych., PPT
Leitung Abteilung für Medizinpsychologie
Klinik für Thorax- und Kardiovaskularchirurgie
Herz- und Diabeteszentrum NRW
Georgstr. 11, 32545 Bad Oeynhausen, Germany
Cite this as:
Tigges-Limmer K, Sitzer M, Gummert J: Perioperative psychological interventions in heart surgery—opportunities and clinical benefit. Dtsch Arztebl Int 2021; 118: 339–45. DOI: 10.3238/arztebl.m2021.0116
Klinikum Herford, Department of Neurology, Herford: Prof. Dr. med. Matthias Sitzer
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