A Systematic Review of Sleep Patterns and Factors That Disturb Sleep After Heart Surgery

Abstract

Background: 

Sleep is a vital and restorative human function. However, it has been reported that up to 50% of heart surgery patients experience sleep disturbance during hospitalization and after discharge.

Purpose: 

This study describes sleep patterns in adults over the recovery course after heart surgery and works to identify potential interventions. Researchers analyzed and synthesized studies of sleep patterns and sleep-related factors in heart surgery patients.

Methods: 

Observational studies describing sleep through the course of recovery from heart surgery were searched from databases of PubMed, MEDLINE, Cumulative Index to Nursing and Allied Health Literature, Current Contents, and Chinese Electronic Periodicals Service from 1966 to 2011. Only studies that used polysomnography, actigraphy, or self-report sleep questionnaires to measure sleep were recruited in this review. Results of sleep patterns and sleep quality were pooled from homogeneity studies.

Results: 

Eight studies that investigated sleep patterns in heart surgery patient and nine studies that examined factors associated with sleep disturbances in this patient group were analyzed and synthesized. Serious problems including low sleep efficiency and difficulty in maintaining sleep often happened during the first postoperative week. It took 2 months for sleep to recover to preoperational levels. Although sleep quality improved over time, sleep disturbances still persisted through 6 months of recovery. Physical factors, including pain, dyspnea, nocturia, and cardiac function, and environmental factors, including noise, light, and procedures on patients, were associated with sleep disturbances during hospitalization. Psychological factors, including anxiety and depression, affected sleep during the first –6 months after discharge. Individual factors of age and gender affected sleep through the entire recovery course.

Conclusions/Implication for Practice: 

Sleep disturbances persist over the course of recovery in heart surgery patients, and sleep disturbance is associated with individual, physiological, psychological, and environmental factors. Findings suggest that management of major symptoms and control of the patient’s sleeping environment during hospitalization and at early recovery stage as well as mental healthcare after discharge may improve sleep quality and recovery in heart surgery patients.

Introduction

Heart surgery is a regular treatment with well-established procedures. However, patients of heart surgery often complain about poor sleep. Sleep disturbance is a major physical distress after heart surgery (^{Abbott, Barnason, & Zimmerman, 2010; Hunt, Hendrata, & Myles, 2000; Hwang, Chan, Hwang, Wu, & Liao, 1997; Peric et al., 2008}) and represents an unmet physical need (^{Doering, McGuire, & Rourke, 2002; Gallagher, McKinley, & Dracup, 2004}). Sleep is vital for proper healing to recover physical and emotional well-being (^{Redeker, Ruggiero, & Hedges, 2004b}). Sleep disturbances can result in delayed recovery and poor quality of life (^{Edell-Gustafsson, Hetta, & Aren, 1999; Hunt et al., 2000; Lukkarinen & Hentinen, 1998; Peric et al., 2008}) and increased coronary artery disease mortality (^{Mallon, Broman, & Hetta, 2002}). It is important to understand how patients sleep to facilitate optimal recovery after heart surgery.

Many studies have addressed sleep patterns and sleep predictors during preoperation, hospitalization, and recovery phases. Deprivation of total sleep time, decreased sleep efficiency, fragmented sleep, and increased daytime napping has been reported in numerous studies (^{Edell-Gustafsson & Hetta, 1999; Redeker & Hedges, 2002; Redeker et al., 2004b; Schaefer, Swavely, Rothenberger, Hess, & Williston, 1996}). Sleep is seriously disturbed in heart surgery patients. Numerous factors, including personal characteristics and extrinsic environmental and medical factors, affect sleep (^{Redeker & Hedges, 2002}). Each study provides partial information during different recovery stages. Merging results from homogeneity studies can make better understanding of when sleep disturbance is improved and how dynamic recovery is achieved.

Purpose

Sleep is a restorative process necessary for proper recovery. Investigating and understanding the dynamic phenomenon of sleep patterns and quality in heart surgery patients is needed for better care. As each study reports results during a limited time after heart surgery, we conducted a systematic review to analyze and synthesize observational studies of sleep patterns and related factors in heart surgery patients to provide an overview of sleep disturbance and related factors throughout the heart surgery recovery process.

Methods

Selecting Review Criteria

Studies of English and Chinese language publications reated to heart surgery (coronary artery bypass grafting [CABG] and valve replacement) and sleep were included in this review. Populations in these studies were adults aged 18 years and older. We limited the search to studies that examined sleep through the course of recovery and excluded studies on topics other than sleep quality after heart surgery, studies targeting pediatric populations, review articles, and case reports.

Sleep involves a series of brain activities and comprehensive body reactions (^{Carskadon & Dement, 2000; Garcia-Rill, 2002; Jones, 2000}). Measuring brain electric activity using polysomnography (PSG) provides the most detailed information about sleep and is the “gold standard” of sleep measure (^{Rechtschaffen & Kales, 1968}). Actigraphy, which uses a convenient and portable activity-monitoring device to estimate sleep, is the most prevalent objective sleep measure (^{Littner et al., 2003; Pollak, Tryon, Nagaraja, & Dzwonczyk, 2001; Shinkoda et al., 1998}). Sleep diaries or similar questionnaires that record sleep time and related sleep indicators provide important information to assess sleep quality (^{Monk et al., 1994}). PSG, actigraphy, and self-reported sleep are three common measures to assess sleep patterns. Studies using these methods to measure sleep provide valid data for assessing sleep that can be merged into a more complete picture of dynamic sleep in heart surgery patients. Therefore, outcome measures should include subjective or objective sleep indicators (such as total sleep time, sleep latency, sleep efficiency, and awakening) assessed using PSG, actigraphy, or self-report sleep questionnaires.

Identifying Related Studies

Researchers searched databases including PubMed, MEDLINE, Cumulative Index to Nursing and Allied Health Literature, Current Contents, and Chinese Electronic Periodicals Service for articles published between 1966 and 2011. Key words used included heart or cardiac surgery and sleep. PubMed returned the most articles (773) by using the key words “heart surgery and sleep.” We began with this initial set and compared these with articles found on other databases. The flow diagram in Figure 1 shows the search process used in this review.

Figure 1: Flow diagram for this review. CINAHL = Cumulative Index to Nursing and Allied Health Literature; CEPS = Chinese Electronic Periodicals Service.

Studies meeting the above selection criteria were included in this review. Sixteen studies related to heart or cardiac surgery and sleep were evaluated. Drug and interventional studies were excluded from the 16 studies. Of these, three were excluded from the review (Figure 1): One of these was an investigation of nurses’ notes on sleep quality (^{Edell-Gustafsson, Aren, Hamrin, & Hetta, 1994}), one was a pilot study on sleep measure reliability in PSG and questionnaires (^{Edell-Gustafsson, Hetta, Aren, & Hamrin, 1997}), and one was a duplicate study (^{Yilmaz & Iskesen, 2007b}). The 13 studies that met the above criteria were analyzed and synthesized (Table 1).

TABLE 1: Summary of Sleep Studies During Hospitalization and Discharge Periods

Assessing Quality of Studies

Eight of these 13 articles used a longitudinal time-series study design to examine sleep patterns and quality in an individual inception cohort of heart surgery patients. Five studies used a descriptive correlational design to examine sleep and related factors in such patients. Study quality was evaluated using the Newcastle–Ottawa Scale (NOS) cohort study form for the assessment of nonrandomized study quality (^{Wells et al., 2005}). Items evaluated in the NOS include selection (4 points for exposed cohort representativeness, selection of the nonexposed cohort, ascertainment of exposure, and the demonstration that outcome of interest was not present at the start of the study), comparability (2 points for comparability of cohorts on the basis of the design or analysis), and outcome (3 points for assessment of outcome, follow-up long enough for outcomes to occur, and adequacy of cohort follow up), with a maximum of 9 points. The NOS is currently the best instrument available for assessing nonrandomized observational studies (^{Buscemi et al., 2005}). All studies selected for this review scored between 6 and 8 points (Table 1), indicating acceptable study quality.

Synthesizing Studies

Results from homogeneity studies that used similar populations and the same sleep measures during the same recovery stage periods were pooled together by calculating their average. Objective sleep parameters, including nighttime sleep hours, daytime sleep hours, wake time minutes, and sleep efficiency (defined as total night sleep time divided by total time in bed and expressed as a percentage value), and subjective sleep quality, assessed by the same questionnaires, were pooled together. Pooled results were then used to describe dynamic sleep patterns and sleep quality in heart surgery patients.

Results

Study Characteristics

Among the 13 studies, 8 (^{Edell-Gustafsson et al., 1999; Edell-Gustafsson & Hetta, 1999; Hedges, 2005; Orr & Stahl, 1977; Redeker, Mason, Wykpisz, & Glica, 1996; Redeker, Ruggiero, & Hedges, 2004a; Schaefer et al., 1996; Yilmaz & Iskesen, 2007a}) assessed sleep patterns over the course of hospitalization and were used in this review to analyze and synthesize recovery from heart surgery in the sleep pattern section. The 9 studies (^{Edell-Gustafsson & Hetta, 1999; Hedges & Redeker, 2008; Knapp-Spooner & Yarcheski, 1992; Redeker et al., 2004a; Schaefer et al., 1996; Simpson & Lee, 1996; Simpson, Lee, & Cameron, 1996a, 1996b; Yilmaz & Iskesen, 2007a}) that investigated factors related to sleep quality among heart surgery patients were used in the associated factor section.

Table 1 summarizes these 13 sleep studies during hospitalization and recovery after heart surgery. Participants were men and women, ranging in age from 30 to 92 years. All of them had undergone heart surgery, CABG, or valve replacement and survived. They were recruited among hospitalized patients, and their conditions were tracked over the course of recovery. Sleep quality was assessed at the ICU, ward, and home at different stages of recovery. Most studies used subjective measurements to assess sleep and identify predictors. Frequently used instruments for self-reporting on sleep and sleep quality included the Pittsburgh Sleep Quality Index (PSQI; ^{Buysse, Reynolds, Monk, Berman, & Kupfer, 1989}), the Verran and Snyder-Halpern Sleep Scale (^{Snyder-Halpern & Verran, 1987}), the Uppsala Sleep Inventory questionnaire for nocturnal sleep and sleep quality, and the Epworth Sleepiness Scale (^{Johns, 1991}) for daytime sleep. Only two studies used PSG to evaluate sleep patterns (^{Edell-Gustafsson et al., 1999; Orr & Stahl, 1977}). Until 2004, subjective and objective actigraphies were combined to assess sleep in heart surgery patients (^{Hedges, 2005; Yilmaz & Iskesen, 2007a}).

Outcomes of Sleep Quality and Sleep Patterns Over the Post-Heart Surgery Recovery Process

Table 2 summarizes sleep results, including PSG sleep, actigraphic sleep, and self-reported sleep quality, in heart surgery patients over the course of recovery.

TABLE 2: Results of Sleep Patterns

Self-reporting is an easy way to assess sleep pattern. It was used in most studies to assess sleep before surgery and at 1, 4, 12, and 24 weeks after surgery (Table 2). More than half (57%) of patients reported sleep disturbances during the first 6 months after surgery (^{Schaefer et al., 1996}). Difficulty maintaining sleep (DMS), that is, an awakening time of more than 30 minutes (^{American Academy of Sleep Medicine, 2005}), was the major sleep disturbance reported (16%–47%; ^{Schaefer et al., 1996}). Sleep latency of longer than 30 minutes (^{Edell-Gustafsson & Hetta, 1999}) indicates difficulty initiating sleep (DIS). Perceived sleep disturbance in terms of DMS and DIS did not decrease over time.

PSG and actigraphy sleep present a more objective pattern of patient sleep quality. ^{Orr and Stahl (1977)} were the first to use PSG to evaluate sleep in heart surgery patients. Sleep was totally absent in the first week after surgery and remained severely deprived 1 month after discharge. All patients reported sleep difficulties (^{Orr & Stahl, 1977}). Improved medical techniques, such as introduction of the off-pump procedure (^{Hedges & Redeker, 2008}), may make these findings less valid today. More recently, ^{Edell-Gustafsson and colleagues (1999)} used portable PSG to assess sleep quality in 38 men scheduled for CABG at 2 days before surgery, the first two postoperative days, and 1 month after discharge. Sleep was severely deprived during the early postoperative days and then recovered back to preoperational sleep pattern at 1 month after surgery (^{Edell-Gustafsson et al., 1999}). Compared with sleep pattern in normal healthy adults, sleep efficiency (77.3%) was still impaired among heart surgery patients, as well as Stages 3 and 4 sleep (16%) and REM sleep (17.5%) at 1 month after surgery. Sleep disturbances of low sleep efficiency, DMS, and less deep sleep were noted before surgery and persisted through 1 month after discharge. Although medical techniques have progressed, sleep disturbance remains a bothersome problem. This study provides important evidence about the nature of PSG sleep in heart surgery patients. However, only male patients participated in these studies. Female patients should be targeted in future studies to account for gender-based sleep differences.

Four studies used actigraphy to assess sleep over the course of postoperative recovery in heart surgery patients (^{Hedges, 2005; Redeker et al., 1996, 2004a; Yilmaz & Iskesen, 2007a}; Table 2). Patient’s sleep during the earlier postoperative days was the worst, especially from the second to the fifth days, when total daily sleep ranged between 4.3 and 6.0 hours. Total daily sleep time gradually decreased from 7.3 to 10.3 hours during hospitalization to 8.8 hours at 6 months after discharge. Sleep efficiency gradually increased from 50.3% to 68.5% during hospitalization to 71.8% after 6 months. However, the number of awakenings per night remained high even after 6 months of recovery. Thirty-nine percent of patients still complained of sleeplessness during the sixth month after discharge. A more recent study in 2007 found a better sleep pattern in 38 patients in the fourth week after discharge (^{Yilmaz & Iskesen, 2007a}). Patients in our review experienced the poorest sleep during hospitalization, and sleep efficiency at the fourth week of recovery had recovered to 92.2% of preoperation levels, which is comparable with healthy adults (^{Carskadon & Dement, 2000}). Figure 2 (a–d) illustrates the dynamic sleep patterns over the course of heart surgery recovery after pooling sleep pattern results (Table 2). Sleep was poorest during hospitalization, with a sleep efficiency of 62.6%. Nighttime sleep hours and sleep efficiency were gradually increased, and daytime sleep hours and the number of awakenings were decreased over the course of recovery. Sleep returned to preoperational levels during the eighth recovery week.

Figure 2: Sleep pattern of (a) nighttime sleep (hours), (b) daytime sleep (hours), (c) average wake time during sleep (minutes), (d) sleep efficiency measured by actigraphy (%), and (e) sleep quality assessed by the Pittsburgh Sleep Quality Index (score, 0–21) at preoperation and during hospitalization and post-discharge recovery periods. Data are pooled from selected studies in Table 2.

The PSQI is a subjective measure of nighttime sleep quality, with total possible scores ranging from 0 to 19. A global score greater than 5 indicates poor sleep quality (^{Buysse et al., 1989}). The PSQI score of sleep quality before cardiac surgery was 2.9 to 7.0 (^{Hedges, 2005; Redeker et al., 2004a; Yilmaz & Iskesen, 2007a}), with sleep quality recovering preoperation levels by the fourth to eighth week after discharge (^{Redeker et al., 2004a; Yilmaz & Iskesen, 2007a}). The Epworth Sleepiness Scale is also a subjective measure of daytime sleepiness, with total possible scores ranging from 0 to 24 and a score of ≥10, indicating sleepiness (^{Johns, 1991}). Perceived daytime sleepiness was high during hospitalization but low after discharge (^{Yilmaz & Iskesen, 2007a}). This indicates fragmented sleep typified by poor nighttime sleep and more daytime sleep during hospitalization. After pooling PSQI assessments (Table 2, pooled results of subjective sleep), sleep quality recovered to preoperational levels during the eighth week after discharge. This result is consistent with that of actigraphic-estimated sleep.

From the above literature reviewed, sleep disturbance is a common problem among heart surgery patients during hospitalization and recovery stage. All patients experienced serious sleep disturbance typified by low sleep efficiency, shorter nighttime sleep, longer daytime sleep, and more awakenings during sleep, especially in the first week after surgery. DMS and low sleep efficiency were the major sleep disturbances. About 2 months was required for sleep to recover to preoperational levels.

Factors Associated With Sleep Disturbance in Heart Surgery Patients

Factors associated with sleep disturbance in heart surgery patients can be classified into individual, physiological, psychological, and environmental factor categories (Table 3).

TABLE 3: Summary of Sleep Associated Factors in Patients Following Cardiac Surgery

Individual factors, such as age and gender, impact sleep in heart surgery patient. Old age was correlated with increased awakenings and longer daytime sleep (^{Redeker et al., 2004a; Simpson & Lee, 1996}). As with younger patients, older patients had a 1-month delay before recovering normal sleep patterns (^{Simpson & Lee, 1996; Yilmaz & Iskesen, 2007a}). In terms of gender differences, women perceived their sleep consistently whereas men did not (^{Simpson & Lee, 1996}). Female patients complained more about DIS than their male counterparts (^{Redeker et al., 2004a}). Therefore, sleep needs differ between men and women. Age and gender should be taken into consideration in sleep assessment work.

Physiological factors, such as pain, dyspnea, fatigue, nocturia, and other symptoms, are associated with sleep disturbance. Pain was the most common cause of sleep difficulty in the initial weeks after heart surgery (^{Schaefer et al., 1996; Simpson et al., 1996a, 1996b}), even up to the 24th week of discharge (^{Schaefer et al., 1996}). Dyspnea and nocturia represented frequent postdischarge complaints (^{Redeker, 1993; Schaefer et al., 1996; Tsai, 1999}). Fatigue that induces excessive daytime sleepiness was caused by sleep disturbance (^{Edell-Gustafsson & Hetta, 1999; Knapp-Spooner & Yarcheski, 1992; Redeker, 1993}). Fatigue was also associated with lower daily activity levels, more depression, and poorer cardiac function (^{Tsai, 1996}). Patients with poorer cardiac function assessed using the functional capacity classification had more sleep disturbances (^{Edell-Gustafsson & Hetta, 1999; Redeker et al., 2004a}). Preoperative sleep pattern was also a predictor of sleep after cardiac surgery (^{Redeker et al., 2004a}). This suggests that personal traits may play a major role in affecting sleep patterns over an individual’s entire life. Other physical factors, including longer duration of cardiopulmonary bypass, longer time under anesthesia, and use of sleep medication, are also associated with sleep disturbances (^{Knapp-Spooner & Yarcheski, 1992}).

Anxiety and depression are two major psychological factors associated with sleep (^{Edell-Gustafsson & Hetta, 1999; Simpson et al., 1996b}). Patients with persistent anxiety experienced sleep disturbance and felt less refreshed after awakening than the nonanxious ones during the first and sixth months after discharge (^{Edell-Gustafsson & Hetta, 1999}). A depressed reaction to sleep loss and inability to relax were significantly associated with such sleep disturbances as DIS, fragmented sleep, and greater feeling of fatigue (^{Edell-Gustafsson & Hetta, 1999; Simpson et al., 1996b}). Hospital and illness-related stress was another psychological factor associated with sleep disturbance (^{Knapp-Spooner & Yarcheski, 1992}).

Most frequently mentioned environmental factors related to sleep disturbances included inability to achieve a comfortable position, inability to perform familiar nighttime routines, medical procedures on patients, unfamiliar bed, nurses’ interruptions, and noise in the ICU and ward (^{Schaefer et al., 1996; Simpson et al., 1996a, 1996b}; Table 3). Light in the room at night was also an important factor affecting sleep (^{Simpson et al., 1996a, 1996b}). Patients ranked all of the above factors in the top 25% of the most bothersome causes of poor sleep.

In summary, physical factors including pain, cardiac function, and fatigue and environmental factors including environmental light, noise, and procedures on patients are main factors associated with sleep disturbance during hospitalization. After discharge, physical symptoms of pain, nocturia, and dyspnea consistently affect sleep quality through the first recovery month. Prolonged pain plus the psychological factors of anxiety and depression affect sleep during the later recovery period (1–6 months after discharge). However, only three studies (^{Edell-Gustafsson & Hetta, 1999; Redeker et al., 2004a; Schaefer et al., 1996}) followed sleep-related factors through the recovery stage. Duration of follow-up varied and focused primarily on the fourth postdischarge week. Although two studies (^{Edell-Gustafsson & Hetta, 1999; Schaefer et al., 1996}) followed up on patient progress for 6 months after discharge, data analysis and inference are limited because of the small sample size.

Discussion

Sleep disturbance is a serious problem among heart surgery patients both during hospitalization and after discharge. Compared with most general adults, sleep in heart surgery patients is far from the norm of 7 to 8 hours of nighttime sleep and 85% or greater sleep efficiency (^{Carskadon & Dement, 2000; Culebras, 2002; Edinger et al., 2004}). Sleep is particularly poor during the first week after surgery (^{Edell-Gustafsson et al., 1999; Orr & Stahl, 1977; Redeker et al., 2004a; Yilmaz & Iskesen, 2007a}). It takes about 2 months for sleep to recover to preoperation levels (Figure 2). However, sleep efficiency has been found to remain below 85% even through 6 months after discharge (^{Redeker et al., 1996}). Pooled data show consistently low sleep efficiency across the recovery course (Figure 2). This phenomenon should encourage healthcare providers to appreciate that successful heart surgery does not necessary guarantee a good quality of life in terms of such facets as sleep quality. The effect on sleep quality of specific factors deserves further examination and consideration.

During hospitalization, all heart surgery patients experienced severe sleep deprivation (^{Edell-Gustafsson et al., 1999; Orr & Stahl, 1977; Redeker et al., 1996}). Sleep disturbance after heart surgery may be endogenous or induced by exogenetic factors. Other predictors of variation in addition to age and gender should be considered to develop effective intervention strategies. In this review, physical factors including pain, dyspnea (^{Simpson, et al., 1996b}), nocturia (^{Schaefer et al., 1996}), and cardiac function (^{Redeker et al., 2004a}) and environment factors including environmental light, noise, procedures on patients, and nurse interruptions (^{Simpson et al., 1996a, 1996b}) were all causes of sleep disturbance. Therefore, management of major symptoms, for example, pain, and better control of the sleeping environment, for example, light and noise disturbances, are important and may improve sleep quality in the first week after heart surgery. Synchronizing patient care schedules with patient circadian rhythms and sleep regulations may help reduce interruptions to a minimum.

After discharge from the hospital, sleep recovery improves slowly but remains poorer than typical sleep quality in healthy older adults. During the first 4 weeks after discharge, symptoms including pain, dyspnea, nocturia, and cardiac function remained significant factors associated with sleep disturbance (^{Edell-Gustafsson & Hetta, 1999; Schaefer et al., 1996}). This means that untreated symptoms persist over time. Identifying and controlling symptoms are important even 6 months after surgery. By the 24th week after discharge, psychological factors, including anxiety and depression, ranked as important factors associated with sleep disturbance ( ^{Edell-Gustafsson & Hetta, 1999}). Therefore, in addition to symptom management, mental healthcare cannot be ignored over the course of recovery. Prevention and management of anxiety and depression in heart surgery patients should be taken into serious account, especially during the first 6 months after discharge.

Sleep is a cyclic phenomenon involving complicated brain electrophysiological activity (^{Blumenfeld, 2002}). Discrepancies exist between subjective and objective sleep measures (^{Baker, Maloney, & Driver, 1999}). Combing subjective and objective sleep measures is necessary to better understand sleep phenomena. However, most studies investigating sleep problems and related factors in heart surgery patients were solely based on self-reporting methods (see Tables 1 and 3, 55.6%). Psychological factors may mediate or moderate self-reported sleep estimations (^{Edinger et al., 2000; Rosa & Bonnet, 2000}). Therefore, objective sleep measures should be adopted in future studies to better assess patient status. Although actigraphy does not provide detailed sleep stage information, it expends objective activity assessment from overnight sleep to daily habitual living in a less invasive way (^{Pollak et al., 2001; Shinkoda et al., 1998}). This provides rich information that closely mirrors real life activities over a 24-hour period, as patients may experience more daytime sleep.

Sleep in patients with heart surgery improves slowly. Only two studies used both subjective and objective sleep measures to examine preoperative status and individual factors associated with sleep disturbances (^{Redeker et al., 2004a; Yilmaz & Iskesen, 2007a}). Other physical, psychological, and environmental factors associated with objective sleep were not examined. Results from this review show that heart surgery patients continue to experience sleep disturbance even 6 months after hospital discharge. Further studies that combine subjective and objective sleep measures are necessary to investigate sleep phenomenon and related factors in heart surgery patients over the course of recovery.

Conclusions and Recommendations

Patients undergoing heart surgery experience serious sleep disturbances, especially during hospitalization. Sleep quality in cardiac patients is significantly poorer than that in the general public. Sleep disturbances identified in this review include low sleep efficiency, DMS, and short nocturnal sleep. It takes about 2 months for sleep to recover to preoperational levels. During hospitalization, physiological and environmental factors including pain, dyspnea, noise, lights, and treatment procedures are associated with sleep disturbance. A comprehensive evaluation of these factors is necessary for sleep assessment and management. Interventions including symptom management and environment control may improve sleep quality. Sleep quality recovers slowly after hospital discharge. Anxiety and depression are essential causal factors in sleep disturbance after discharge, especially during the first 6 months. Mental healthcare after discharge is vital to improve sleep quality and recovery. Further study combining objective and subjective sleep measures to examine sleep and associated factors over the course of recovery in heart surgery patients is needed.