The aim of this literature review was to evaluate existing evidence on exercise-based cardiac rehabilitation (CR) as a treatment option for elderly frail patients with valvular heart disease (VHD).
Worldwide, the population is aging, and the associated challenges for the healthcare system are significant. There is a clear association between degenerative valve disease, older age, and increasing life expectancy [
Careful monitoring, adequate medication, and perfect surgery or intervention timing is key to a successful treatment of VHD. Due to the shift in patient population, the profile of patients who are referred to cardiac surgeon changed dramatically. The share of surgically treated elderly patients (≥80 years old) increased from 2.6-7% to 9.3-12% in a period of 10 years [
Disease complexity in the elderly raises questions about other risk factors that exist upon well-known and established prognostic factors. Frailty is a common and relevant geriatric syndrome that could be defined as a biological syndrome with reduced reserve and resistance to stressors, resulting from cumulative deficits across multiple physiologic systems and causing vulnerability to adverse outcomes [
The aim of this literature review was to evaluate existing evidence on exercise-based cardiac rehabilitation (CR) as a treatment option for elderly frail VHD patients. This literature review aimed to assess the following issues: Are assessment tools used for frailty screening sensitive enough to show improvement in frailty status after exercise-based CR? What exercise interventions would be the most beneficial for frail patients? Would the change of frailty status improve outcomes on levels of disability, functional capacity, and quality of life after surgical/interventional VHD treatment beyond the effects of the surgery/intervention itself?
We conducted a literature review of articles published from 1980 to January 2018. Literature search was performed using the PubMed database. Relevant studies were identified using the following key words: valve surgery/TAVI and exercise training, cardiac rehabilitation, moderate aerobic exercise training, high intensity interval training, resistance training, strength training, exercise capacity, prognosis, mortality, frailty, and sarcopenia. Additionally, we manually searched the bibliographies of all included articles.
The search was limited to publications related to adults over 60 years old and published in English (see Figures
Flowchart of the selection of publications included in literature review related to valve surgery and exercise training.
Flowchart of the selection of publications included in literature review related to valve surgery and frailty.
In order to answer first research question we describe most often used frailty tools for screening in patients with VHD and compare results with frailty assessment methods used in a setting of CR.
Large variety of methods and instruments are used to describe existence or/and level of frailty for patients with VHD (Table
Characteristics of reviewed studies on frailty and VHD.
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| N=805; | TAVI | (1) MFFC | (1) To assess the influence of BMI on the short- and midterm clinical outcome following TAVI. | (1) Obese patients had lower prevalence of frailty. |
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| N=167; | Cardiac surgery 39 (23%) | (1) FFS | (1) Impact of frailty on outcomes of patients undergoing cardiac surgery | (1) Frail patients had longer median ICU stays (54 vs. 28h, p=0.003), longer median LOS (8 vs. 5 days, p<0.001), greater likelihood of STS-defined complications (54% vs. 32%, p=0.011), and discharge to an intermediate-care facility (45% vs. 12%, p<0.001) |
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| N=131; | Open cardiac surgery | (1) 5MWT | (1) Inhospital post-operative mortality or major morbidity, defined by the STS. | (1) Slow gait speed was an independent predictor of the composite end point after adjusting for the STS risk score (OR: 3.05; 95% CI: 1.23 to 7.54). |
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| N=152; | Cardiac surgery 20%- 46% | (1) FFS | (1) The STS composite end point of in-hospital postoperative mortality or major morbidity | (1) The most predictive scale in each domain was 5MWT |
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| N=15171; | Cardiac surgery 4588 (30,24%) | (1) 5MWT | (1) Operative mortality or within 30 d | (1) Compared with patients in the fastest gait speed tertile, operative mortality was increased for those in the middle tertile (0.83-1.00m/s; OR, 1.77; 95% CI, 1.34-2.34) and slowest tertile. |
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| N=1020; | SAVR, TAVI 26-68% | (1) FFS | (1)Death from any cause at 12 mo | (1) EFT was the strongest predictor of death at 1 y (adjusted [OR]: 3.72; 95% [CI]: 2.54 to 5.45). |
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| N=8039; | TAVI | (1) 5MWT | (1) all-cause mortality at 30 d | (1) 30-d all-cause mortality rates were 8.4%, 6.6%, and 5.4% for the slowest, slow, and normal walkers, respectively (P<0.001). |
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| N=2830; | TAVI | (1) FFS | (1) death within the first 6 mo after TAVI; | (1) For all models except the 1-year clinical model, frailty was associated with an increase in the odds of a poor outcome of 30% to 40% when added to the existing models; |
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| N=89; | TAVI | (1) MGA/MGBE | (1) Postprocedural period, mortality in 30 d follow-up | (1) Variables from frailty assessment protectively associated with delirium were MMSE, IADL and gait speed |
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| N=141; | TAVI | (1) 5MWT, | (1) All-cause mortality at 30 d and 12 mo | (1) 30-d and 12-mo all-cause mortality rates were higher in the delirium group (p <0.001). |
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| N=150; | TAVI | (1) Low albumin | (1) Correlation between baseline serum albumin and all-cause mortality in TAVI patients. | (1) Mortality was higher in the low albumin group compared with the normal albumin group (35% vs. 19%, p=0.01). |
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| N=1878 | TAVI | (1) Geriatric status scale | (1) 30-d mortality | (1) Frailty OR 2.09, CI (1.30-3.37), p =0.003 |
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| N=342; | TAVI | (1) MFFC | (1) all-cause mortality | (1) Patients with frailty score of 3/4 or 4/4 had increased all-cause mortality (P = 0.015 and P <0.001) and were more likely to be discharged to an ICU facility (P =0.083 and P = 0.001). |
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| N=312; | TAVI | (1) General mobility EuroSCORE II | (1) Assess whether different frailty indices predict outcomes both in the shorter and longer terms | (1) Both univariate and multivariate analyses confirmed poor mobility (EuroSCORE II), as the best predictor of adverse outcome over both the short-term (OR 4.03, 95% CI (1.36–11.96), P50.012 (30 days)) and longer term (OR 2.15, 95% CI (1.33–3.48), P50.002, (2.261.5 years.) |
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| N=360; | TAVI | (1) 5MWT | All-cause mortality during follow-up. | In multivariate analysis frailty (HR 1.89, 95% CI 1.11 to 3.2, p =0.02) was independent predictor for all-cause mortality. |
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| N=104, | TAVI | CT scan – SMI | (1) Relationship between SMI and LOS | (1) A multivariate model showed SMI as independent predictors of LOS. |
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| N=49; | TAVI | (1) G8 scale | (1) sensitivity and specificity of G8 | (1) G8 had a sensibility of 100% (IC 95% [0.91]), a specificity of 72.7% (IC 95% [0.430.9]), a positive predictive value of 92.6% and a negative prospective value of 100% (IC: 95%). |
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| N=511 | TAVI | (1) FFS | (1) 1y mortality | (1) Frailty was not associated with the study end point |
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| N=344; | TAVI | (1) MGA/MGBE | (1) All-cause mortality at 12 mo after TAVI. | (1) MGA/MGBE had no predictive power; its individual components, particularly nutrition (OR 0.83 per 1 pt., CI 0.72–0.95; p=0.006) and mobility (OR 5.12, CI 1.64–16.01; p=0.005) had a prognostic impact. |
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| N= 3088; | SAVR | (1) modified CSHA | (1) 30-d mortality and major postoperative morbidity. | (1) Frailty was a better predictor of mortality than morbidity, and it was not markedly different among any of the 3 indices. |
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| N=361; | TAVI | MFFC | (1) 30-d mortality and to compare the discrimination of 30-d mortality, and to compare its discriminative ability with STS PROM. | (1) For high- and extreme-risk patients undergoing TAVR, serum albumin, Katz Index, and 5MWT were associated with increased risk of adverse outcomes. |
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| N=152; | TAVI | (1) CT scan - PMA | (1) early poor outcome (30 d mortality, stroke, dialysis, and prolonged ventilation | (1) Indexed PMA ([OR] 3.19, [CI] 1.30 to 7.83; p =0.012) and age (OR 1.92, CI 1.87 to 1.98; p = 0.012) predicted early poor outcome. |
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| N=235 | Cardiac surgery | FFS or SPPB | (1) The impact of preoperative frailty status on postoperative hospitalization costs | (1) The median cost was |
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| N=484; | TAVI | (1) 6MWT | (1) association between baseline 6MWT and functional improvement | (1) There were no differences in 30-d outcomes among 6MWTD groups. |
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| N=244; | TAVI | (1) MFFC | (1) Time to death from any cause over 1 y of follow up and poor outcome at 1y | (1) At 30 d, there were no differences in rates of MACCE according to baseline frailty status. |
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| N=426; | TAVI | (1) Low albumin | (2) 1-y all-cause mortality. | (1) Participants with low albumin levels had higher mortality (HR) = 3.03, 95% (CI) = 1.66–5.26, P < .001). |
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| N=4270; | Cardiac surgery 171 (4%) | (1) Katz index | (1) Composite end point defined as MACCE | (1) Frailty was significant (OR 1.7; 95% CI 1.2-2.5) predictor. |
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| N=3687; | TAVI | (1) 5MWT | All-cause mortality rate 30 d and 1 y | (1) Albumin levels <3.3 g/dl predicted death at 30 d. |
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| N=191 | TAVI | FFS | (1) 30-d mortality, AE, hospital readmission | (1) There was no difference in 30-d mortality, major complications, mean hospital LOS, 30-day hospital re-admission, or overall survival between groups. |
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| N=30; | TAVI | (1) The ISAR | (1) Outcomes 30 d and 1 y | (1) The ISAR score was similar but the SHERPA score was significantly higher in non-survivors (7.8 ±1.6 vs. 4.9 ±2.4; P = 0.001). |
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| N=1256; | TAVI | (1) 5MWT | (1) 30 d and 12 mo mortality | (1) The slowest walkers and those unable to walk demonstrated independent associations with increased midterm mortality after adjustment (HR, 1.83, 4.28; 95% CI, 1.03–3.26, 2.22–8.72; P=0.039, <0.001, respectively). |
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| N=101; | TAVI | (1) Katz index | 12-mo mortality | (1) Associations between frailty indices and 12-mo all-cause mortality were significant, adjusted for logistic EuroSCORE: |
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| N=130; | TAVI | (1) FORECAST | (1) 12-mo mortality | (1) ROC showed that the FORECAST is a valid tool to predict in-hospital mortality (area 0.73). |
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| N=491; | TAVI | BMI | (1) all-cause mortality at 1 y of follow-up | (1) All-cause mortality at 1 y was higher in the low-BMI group (log-rank p=0.003) with no significant difference among normal and above-normal BMI patients. |
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| N=103; | SAVR | (1) CSHA | (1) to determine the extent to which surgery affected measures of physical and mental health and QoL, | (1) Frail participants had lower baseline independence and QoL measures; |
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| N=116; | TAVI | MPI score the sum of | All cause of mortality at 1 mo | Mortality rate was significantly different between MPI groups at 6 and 12 mo (p=0.040 and p=0.022). Kaplan Meier survival estimates at 1 y stratified by MPI groups were significantly different (HR=2.83, 95% (CI) 1.38–5.82, p=0.004). Among variables retained to perform logistic regression analysis, Katz index appeared the most relevant (p < 0.001). |
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| N=3826; | Cardiac surgery 157 (4.1%) | (1) Katz index | (1) In-hospital mortality, midterm all-cause mortality and discharge to an institution | (1) Frailty was an independent predictor of in-hospital mortality (OR 1.8, 95% CI 1.1 to 3.0), as well as institutional discharge (OR 6.3, 95% CI 4.2 to 9.4). |
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| N=208; | TAVI | (1) CT scan – PMA | All-cause mortality | (1) PMA was lower in non-survivors compared with survivors among women (12.9 vs 14.5 cm2; P = 0.047) but not men (21.7 vs 22.4 cm2; P = 0.50). |
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| N=6339; | TAVI | (1) Katz Index | (1) Internally validate a multivariable TAVI CPM for predicting 30-d mortality in UK-TAVI patients | (1) The final UK-TAVI CPM included 15 risk factors, which included 2 variables associated with frailty. |
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| N=213 | PMVR | (1) FFS | (1) procedural outcomes, short-term functional changes, and long-term clinical outcomes | (1) Mortality at 6 w was significantly higher in frail (8.3%) compared with nonfrail (1.7%) patients (p =0.03). Hazards of death (HR: 3.06; 95% CI: 1.54 to 6.07; p <0.001) and death or heart failure decompensation (HR 2.03; 95% CI 1.22 to 3.39; p. 0.007) were significantly increased in frail patients during long-term follow-up, which did not change relevantly after adjustment |
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| N=460; | TAVI Sarcopenia 293 (64%) | (1) CT scan – SMM, FM | (1) assess the feasibility of evaluating body composition by CT | (1) Sarcopenia predicted cumulative mortality (HR 1.55, 95% confidence interval 1.02 to 2.36, p=0.04). |
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| N=238; | TAVI | (1) CT scan - SMI | (1) inter- and postprocedural complications | (1) SMIs at L3 and T12 significantly correlated with prolonged LOS. |
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| N=75; | TAVI | FFS | (1) all-cause mortality | (1) Significant improvement in overall health status of non-frail patients (mean difference: 11.03, P=0.032). |
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| N=295; | SAVR/TAVI NA | (1) CT scan - TPA | (1) To evaluate the use of sarcopenia as a frailty assessment tool | (1) 2 y survival was 85.7% in patients with sarcopenia, compared with 93.8% in patients without sarcopenia (P = .02). |
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| N=300; | TAVI | (1) Katz Index | (1) all-cause mortality | (1) Early mortality was significantly higher in frail persons (5.5% vs. 1.3%, p=0.04 for immediate procedural mortality; 17% vs. 5.8%, p=0.002 for 30-day mortality; and 23% vs. 6.4%, p<0.0001 for procedural mortality). |
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| N=339; | TAVI | Eye ball test | (1) Procedural and 30-d outcomes | (1) Patients with either porcelain aorta (18%) or frailty (25%) exhibited acute outcomes similar to the rest of the study population |
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| N=339; | TAVI; | Eye ball test | (1) the occurrence of mortality (yes/no) | (1) At a mean follow-up 188 patients (55.5%) had died. |
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| N=221; | Cardiac surgery; Pre-frailty 144 (65,15%) | (1) CSHA | (1) main outcomes after cardiovascular surgery in pre-frail patients compared with non-frail patients. | (1) Pre-frail patients showed a longer mechanical ventilation time (193 ± 37 vs. 29 ± 7 hours; p<0.05), LOS at ICU (5 ± 1 vs. 3 ± 1 days; p < 0.05) and total time of hospitalization (12 ± 5 vs. 9 ± 3 days; p < 0.05). |
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| N=606; | TAVI/SAVR 299 (49.3%) | (1) FFS | (1) all-cause mortality during the follow-up | (1) The HR (95% CI) of mortality among frail versus non-frail patients was 1.83 (1.33–2.51). |
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| N=85; | AVR | (1) FIM | (1) whether the preoperative FIM is useful for decision making for a strategy in the era of TAVI | (1) The preoperative motor FIM score was significantly lower in the compromised group (45 ± 24) than in the unaffected group (85 ± 9, p =<0.01). |
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| N=232; | TAVR; | (1) CT scan - PMA | (1) all-cause mortality at 30 d and 6 mo. | (1) After adjustment for multiple confounding factors, the normalized PMA tertile was independently associated with mortality at 6 mo (adjusted HR 1.53, 95%, CI 1.06 to 2.21). |
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| N=155; | TAVI | (1) SPPB | (1) all-cause unplanned readmission following TAVI | (1) Frailty markers other than MFFC were independently associated with unplanned readmission. |
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| N=119; | | (1) MGA/MGBE | (1) Functional decline over 6 mo | (1) The frailty index strongly predicted functional decline in univariable (OR per 1 point increase 1.57, 95% CI: 1.20–2.05, P = 0.001) and bivariable analyses (OR: 1.56, 95% CI: 1.20–2.04, P = 0.001 controlled for EuroSCORE; OR: 1.53, 95% CI: 1.17–2.02, P = 0.002 controlled for STS score). |
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| N=845; | TAVI | (1) CSHA | (1) to determine the additional value of indicators of frailty for postoperative survival in the elderly patient sample in the last step | (1) BMI, eGFR, hemoglobin, pulmonary hypertension, mean transvalvular gradient and LV ejection fraction at baseline were most strongly associated with mortality and entered the risk prediction algorithm [C -statistic 0.66, 95 % confidence interval (CI) 0.61–0.70, calibration v2 -statistic = 6.51; P = 0.69]. |
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| N=1215; | TAVI | (1) CSHA | The 30-d mortality and in-hospital mortality | (1) Cumulative 1-y mortality increased with increasing CSHA stage (7.2%, 8.6%. 15.7%, 16.9%, 44.1%, p<0.001). |
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| N=100; | TAVI | (1) MGA/MGBE | (1) outcomes at 30 day and 1 year | (1) Associations of cognitive impairment (odds ratio [OR]: 2.98, 95% confidence interval [CI]: 1.07 to 8.31), malnutrition (OR: 6.72, 95% CI: 2.04 to 22.17), mobility impairment (OR: 6.65, 95% CI: 2.15 to 20.52), limitations in basic ADL (OR: 3.63, 95% CI: 1.29 to 10.23), and frailty index (OR: 3.68, 95% CI: 1.21 to 11.19) with 1-year mortality were similar compared with STS score (OR: 5.47, 95% CI: 1.48 to 20.22) and EuroSCORE (OR: 4.02, 95% CI: 0.86 to 18.70). |
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| N=400 | Cardiac surgery | (1) CAF | (1) correlation of Frailty score to 30-d mortality. | (1) There were low-to-moderate albeit significant correlations of Frailty score with STS score and EuroSCORE ( p < 0.05). |
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| N=400; | Cardiac surgery 114 (55,33% ) | CAF | (1) 1 y all-cause mortality | (1) Patients who died within 1 y had a median frailty score of 16 [5;33] compared to 11 [3;33] to the 1 y survivors (P = 0.001). |
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| N=777; | TAVI | BMI | (1) The 30- d mortality | (1) Kaplan-Meier curves indicated no significant differences in cumulative 30-d and 1-y survival. |
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| N=1215; | TAVI | (1) Low albumin | (1) all-cause mortality after TAVI | (1) cumulative all-cause, cardiovascular, and noncardiovascular mortality rates were significantly higher in the low albumin group than in the normal albumin group (log-rank test, p <0.001, p = 0.0021, and p <0.001, respectively). |
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| N=82; | Cardiac surgery NA | (1) CT scan - PMA | (1) postoperative LOS defined as the number of days from index procedure to hospital discharge | (1) Low PMA was correlated with lower handgrip strength and SPPB scores indicative of physical frailty. |
FFS represents the definition of physical frailty and it is based on the results of the Cardiovascular Health Study and the Women’s Health and Aging Studies [
However, the study that validated the FFS was performed with general population. There is no information about VHD patients, and the share of very old individuals included in the study was relatively low (3.6% of patients were 85 years or older) [
FFS [
Stortecky et al. and Schoenenberger et al. showed MGA/MGBE to be a good predictor of mortality and major adverse cardiovascular and cerebral events (MACCE) [
In addition, Eichler et al. showed that this instrument could be used in CR settings, although there were no changes in Katz index and IADL results after 3-4 weeks of inpatient CR for patients after TAVI [
However, other authors have not confirmed the predictive value of this instrument and found that it only partly predicted unfavorable outcome after TAVI (nutrition and mobility) [
CSHA scale is a multidomain approach that defines frailty as a proportion of accumulated health deficits [
One of the requirements for frailty assessment (especially for screening) is simplicity and ability to assess frailty in a very short period of time. One of the most evaluated frailty assessments is the 5-meter (15 feet ~ 4,5 meters) walking test which can be used as part of other scales (FFS) or as stand-alone evaluation [
Pre-procedural albumin levels (as single measurement or as part of other indexes) have been demonstrated to have significant predictive value [
Albumin level seems to have higher prediction value and could be a good screening instrument for frailty. What is more, serum albumin levels can be linked to lower muscle mass in elderly [
The Katz index is used for functional assessment of dependency in elderly individuals in the six functions: feeding, bathing, dressing, transferring, toileting, and urinary continence [
In order to answer the second research question, we analyzed 12 studies published in English since 1980 on topic of VHD and exercise training with elderly (Table
Characteristics of reviewed studies on VHD and exercise training.
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Zanettini (2014) [ | N=60; | CR inpatient; | (1) to determine the in-hospital and mid-term outcomes of these patients. | AE: NA | Most patients showed significant improvement in functional status, QoL, and autonomy, which remained stable in the majority of subjects during mid-term follow-up. |
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Russo | N=158; | CR inpatient; | (1) The safety and efficacy of a structured, exercise-based CR program | AE: none | CR is feasible, safe and effective in octogenarian patients after TAVI as well as after traditional surgery. CR rehabilitation programme enhances independence, mobility and functional capacity and should be highly encouraged |
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Pardaens (2014) [ | N=145; | CR outpatient; | (1) difference in exercise capacity early after VHD surgery | AE: NA | (1) Exercise capacity after VHD surgery is related to the preoperative risk and to the type of surgery. |
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Fauchere (2014) [ | N=112; | CR inpatient; | (1) improvement during the CD in FIM-score, HADS-score and 6-MWT | AE: NA | (1) Patients in TAVI group were older and sicker than SAVR |
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Baldasseroni | N=160; | CR outpatient; | (1) effects of an exercise-based CR program on exercise tolerance and muscle strength (2) the independent predictors of changes in physical performance | AE: none | (1) An exercise-based CR program was associated with improvement in all domains of physical performance even in older adults after an acute coronary event or cardiac surgical intervention, particularly in those with poorer baseline performance. |
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Voller (2015) [ | N=442; | CR inpatient; | (1) the effect of CR on in patients after TAVI in comparison to patients after sAVR | AE: NA | (1) Patients after TAVI benefit from CR despite their older age and comorbidities. (2) CR is a helpful tool to maintain independency for daily life activities and participation in socio-cultural life. |
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Savage | N=576; | CR outpatient; | (1) If patients after HVD benefit similarly CR as CABG. | AE: NA | CABG and VHD patients experienced similar improvements in strength, and self-reported physical function and depression scores. |
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Pressler (2016) [ | N=30; | CR outpatient; | (1) difference in change in VO2 peak from baseline | AE: 3, not related | In patients after TAVI, ET appears safe and highly effective with respect to improvements in exercise capacity, muscular strength, and quality of life. |
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Sibilitz | N=147; | CR outpatient/home based; | (1) Improved physical capacity (VO2 peak) | AE: Int.:13pts vs cont. 3pts, not related | CR after HVD surgery significantly improves VO2 peak at 4 months but has no effect on mental health and other measures of exercise capacity and self-reported outcomes. |
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Genta (2017) [ | N=135; | CR inpatient; | (1) Improved BI (2) Decreased risk of falls | AE: 9pts (not related) | (1) Intensive CR after TAVI is safe, well tolerated, and leads to a net improvement in disability, risk of falls, and exercise capacity, similar to that observed in less disabled SAVR patients. |
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Pollman (2017) | N=168; | CR outpatient; | (1) the effect of CR after VHD surgery on VO2 peak, long term morbidity, mortality | AE: none | CR after VHD surgery improved exercise capacity and was associated with reduced morbidity. Elderly were less likely to attend or complete CR and deserve special attention |
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Eichler (2017) | N=136; | CR inpatient; | (1) effect of a multicomponent inpatient CR after TAVI | AE: NA | CR can improve functional capacity as well as QoL and reduce frailty in patients after TAVI. |
Although recently published studies concentrate on disabled, comorbid high-risk elderly patients, all authors demonstrated that exercise training is safe and effective in improving functional and physical capacity [
Only two randomized controlled trials (RCT) were performed with patients aged 60 years or older [
None of these studies assessed level of patients frailty before and after exercise training program; on the other hand, it did show that structured training program could improve older patient physical capacity [
Only one study, conducted by Eichler et al., evaluated the effect of a multicomponent inpatient CR on frailty in patients after TAVI [
Russo et al. showed that early cardiac rehabilitation enhances independence evaluated with Barthel index, mobility, and functional capacity for patients after surgical or interventional aortic stenosis treatment. The exercise training consisted of aerobic training and calisthenics [
Summarizing of existing evidence on exercise training for patients with VHD would show that exercise program should be individualized and intensity should be measured by RPE with beginning of 40-60% of maximal VO2. All analyzed training protocols included aerobic training component implemented through various activities (Nordic walking, bicycle ergometer, gymnastics, etc.) and in 9 of them additional strength training was performed starting form the second or third week of exercise training, measuring intensity with 1 repetition maximum method. Inpatient CR program length varied from 2 to 4 weeks, while the duration of the outpatient programs was 12-24 weeks.
According to recent studies, in 23-32,8% of cases functional capacity of TAVI patients did not improve or even deteriorate in a period of 6-12 months after intervention [
After analyzing the reviewed studies, we could not directly answer to the third research question. Two studies that were designed as RCT did not evaluated frailty or its components [
Participation in CR improves outcomes of patients with cardiovascular disease [
The results of this review highlight the importance of frailty syndrome in patients with VHD. Screening for frailty as a high-risk factor is well implemented in Heart team decision making for high-risk patients with aortic stenosis. However, there is gap of evidence considering frailty in CR settings. This literature review was designed to seek for answers of several research questions: Are assessment tools used for frailty screening sensitive enough to show improvement in frailty status after exercise-based CR? What exercise interventions would be the most beneficial for frail patients? Would the change of frailty status improve outcomes on levels of disability, functional capacity, and quality of life after surgical/interventional VHD treatment beyond the effects of the surgery/intervention itself?
First of all, our analysis revealed several different methods used for frailty assessment and evaluation. The analysis of these frailty tools was difficult because (1) a huge variety of instruments were used, (2) the same instruments were chosen to evaluate disability or cognitive functions in some studies and frailty in others, (3) the same instruments were named differently in separate studies, (4) authors were using validated scales but chose to analyze components separately, (5) authors created and offered new risk scores for frailty assessment that has not been implemented in other studies, and (6) some studies described subjective frailty evaluation manner “eye-ball test” [
It is clear that the prevalence of frailty plays an important role for patients with VHD: recently updated AHA VHD and ESC guidelines emphasize the frailty issue as an important factor for Heart team decision making in patients with aortic stenosis [
Existing literature confirms frailty predictive value for higher complications rate, longer length of hospital stay, and mortality and morbidity after cardiac surgery or interventional treatment [
Vigorito et al. recently published a call for action on frailty in CR and offer mainly two instruments for frailty assessment in this specific field: Edmonton frailty scale (EFS) and clinical frailty scale from the CSHA study. The EFS could be used as a comprehensive instrument that has been validated in elderly patients after acute coronary syndromes [
Our analysis revealed the six most used tools for frailty in VHD population: 3 scales (fried frailty scale and its modifications, multidimensional geriatric assessment, and clinical frailty scale from the CSHA study) and 3 single measures (5-meter walking test, Katz index, and serum albumin levels). Together with existing guidelines and expert opinions we believe that simple and fast-performed single test would not show comprehensive CR effect on a frail patient. An instrument of frailty assessment in CR should have the various components included in different risk assessment scores (mobility, independence in daily living, cognitive functions, nutrition, muscle mass and strength, and anxiety and depression evaluation). We did not find enough studies performed in CR with frail patients to find out which of all the mentioned tools is the best and most sensitive for frailty syndrome and its dynamics after CR program. Future studies are needed to build new evidence in this field of research.
Second research question aim was to find an ideal exercise training-based CR program for frail patient with VHD. It is known that exercise-based comprehensive CR is based on strong evidence and is a well-recognized treatment for patients with different cardiovascular diseases [
However, literature data in exercise training and CR in VHD patients is scare [
All reviewed studies had an aerobic component of exercise training that was fulfilled in different ways, and 9 of 12 reviewed studies had an additional strength-training component. All described exercise programs were individualized according to the patient capability and described careful exercise intensity dosage according to rate of perceived exertion. We believe that ideal CR for VHD patients should be supervised by a cardiologist, and its content should include (1) exercise training (endurance and strength training to improve muscle mass, strength, balance, and coordination and to avoid falls), (2) nutrition counseling (to improve healthy body mass), (3) occupational therapy (to improve independency and cognitive function), (4) psychological counseling to ensure psychosocial health, and (5) social worker counseling (to improve independency). To improve outcomes of these patients CR services need to be optimally utilized and the protocols modified to cater for frail patients and to monitor their progress over the course of the treatment [
Our literature review has several limitations and weaknesses. First of all, it was not designed as a meta-analysis or systematic review, so results of our study have lower evidence level. We searched only one database and used informal and subjective methods for studies inclusion and quality check. A quality assessment of the included studies would have strengthened our study.
What is more, we failed to find concrete and practical answers for research questions that were raised in the beginning of the study. We could only provide existing situation and try to find possible goals for future studies.
Frailty assessment in CR settings should be based on functional, objective tests and should have similar components as tools for risk assessment (mobility, muscle mass and strength, independence in daily living, cognitive functions, nutrition, and anxiety and depression evaluation). Participating in comprehensive exercise-based CR could improve short- and long-term outcomes in frail VHD patient. Comprehensive CR not only should include exercise training, psychological interventions, and improvement in nutrition but also could prevent, restore, and reduce the severity of frailty as well as improving outcomes for frail VHD patients.
The authors declare that there are no conflicts of interest regarding the publication of this paper.