Prognostic value of exercise capacity as evaluated by the 6-minute walk test in patients undergoing transcatheter aortic valve implantation

Sarcopenia and frailty in patients undergoing transcatheter aortic valve replacement

BACKGROUND

Skeletal muscle mass (SMM) plays a crucial role in risk assessment in transcatheter aortic valve replacement (TAVR) candidates, yet it remains underutilized. Traditional methods focus on weakness or performance but omit SMM. This study compared traditional and novel markers of sarcopenia and frailty in terms of their ability to predict adverse outcomes post-TAVR.

METHODS

Three risk models were evaluated for the composite outcome of perioperative complications, 1-year rehospitalization, or 1-year mortality: (1) sarcopenia by combining low muscle mass (LMM) and weakness/performance assessed by hand grip strength or gait speed; (2) frailty by an Adapted Green score; and (3) frailty by the Green-SMI score incorporating LMM by multilevel opportunistic pre-TAVR thoracic CT segmentation.

RESULTS

In this study we included 184 eligible patients from January to December of 2018, (96.7%) of which were balloon expandable valves. The three risk models identified 22.8% patients as sarcopenic, 63.6% as frail by the Adapted Green score, and 53.8% as frail by the Green-SMI score. There were higher rates of the composite outcome in patients with sarcopenia (54.8%) and frailty (41.9% with the Adapted Green and 50.5% with the Green-SMI score) compared to their nonsarcopenic (30.3%) and nonfrail counterparts (25.4% with the Adapted Green and 18.8% with the Green-SMI score). Sarcopenia and frailty by Green-SMI, but not by the Adapted Green, were associated with higher risks of the composite outcome on multivariable adjustment (HR 2.2 [95% CI: 1.25-4.02], P = .007 and HR 3.4 [95% CI: 1.75-6.65], P < .001, respectively).

CONCLUSIONS

The integration of preoperative CT-based SMM to a frailty score significantly improves the prediction of adverse outcomes in patients undergoing TAVR.

Cardiac Health Assessment Using a Wearable Device Before and After Transcatheter Aortic Valve Implantation: Prospective Study

Background

Due to aging of the population, the prevalence of aortic valve stenosis will increase drastically in upcoming years. Consequently, transcatheter aortic valve implantation (TAVI) procedures will also expand worldwide. Optimal selection of patients who benefit with improved symptoms and prognoses is key, since TAVI is not without its risks. Currently, we are not able to adequately predict functional outcomes after TAVI. Quality of life measurement tools and traditional functional assessment tests do not always agree and can depend on factors unrelated to heart disease. Activity tracking using wearable devices might provide a more comprehensive assessment.

Objective

This study aimed to identify objective parameters (eg, change in heart rate) associated with improvement after TAVI for severe aortic stenosis from a wearable device.

Methods

In total, 100 patients undergoing routine TAVI wore a Philips Health Watch device for 1 week before and after the procedure. Watch data were analyzed offline-before TAVI for 97 patients and after TAVI for 75 patients.

Results

Parameters such as the total number of steps and activity time did not change, in contrast to improvements in the 6-minute walking test (6MWT) and physical limitation domain of the transformed WHOQOL-BREF questionnaire.

Conclusions

These findings, in an older TAVI population, show that watch-based parameters, such as the number of steps, do not change after TAVI, unlike traditional 6MWT and QoL assessments. Basic wearable device parameters might be less appropriate for measuring treatment effects from TAVI.

Efficacy of exercise training-based cardiac rehabilitation programmes after transcatheter aortic valve implantation: A systematic review and meta-analysis

Background

The beneficial effects of exercise training-based cardiac rehabilitation (CR) in different cardiac conditions have been previously studied. In this meta-analysis, we focused on the potential impact of CR on patients undergoing transcatheter aortic valve implantation (TAVI).

Methods

Multiple databases were searched in a systematic approach to find the eligible studies. All the studies investigating the potential impact of exercise training-based CR programmes on exercise capacity and health-related quality of life in patients undergoing TAVI were retrieved. The primary endpoint of interest was 6-min walk test (6MWT). The pooled standardized mean difference (SMD) and 95 % confidence interval (CI) were measured to compare the improvement or worsening the endpoints using a random- or fixed-effects model, as appropriate.

Results

A total of eleven studies (685 patients) were considered eligible for quantitative synthesis. The results showed that performing exercise training-based CR after TAVI is associated with significant improvement in 6MWT (SMD 0.59, 95 % CI (0.48; 0.71), p < 0.01), Barthel index (SMD 0.73, 95 % CI (0.57; 0.89), p < 0.01), 12-item Short Form (SF-12) physical (SMD 0.30, 95 % CI (0.08; 0.52), p < 0.01) and mental (SMD 0.27, 95 % CI (0.05; 0.49), p = 0.02) survey scores, and hospital anxiety and depression scale - depression (HADS-D) score (SMD -0.26, 95 % CI (-0.42; -0.10), p < 0.01).

Conclusion

Performing exercise training-based CR following TAVI has significant benefits regarding physical capacity and health-related quality of life irrespective of the programme duration.

Early Heart Rate Recovery after a 6-min Walking Test Predicts Clinical Benefits in Patients after Percutaneous Aortic Valve Implantation

BACKGROUND

It was hypothesized that the time-appropriate return to a resting heart rate (HR) after cessation of exercise could be a marker for predicting outcomes in patients with heart failure (HF). We aimed to evaluate the prognostic value of HR recovery in functional improvement among adults with severe aortic stenosis undergoing percutaneous aortic valve implantation (TAVI).

METHODS

We performed a 6 min walk test (6MWT) in 93 individuals before TAVI and 3 months after the procedure. The change in walking distance was calculated. During the pre-TAVI 6MWT, we analyzed the differences between baseline HR, HR at the end of the test, and HR at the 1st, 2nd, and 3rd minute of recovery.

RESULTS

After 3 months, 6MWT distances improved by 39 ± 63 m and reached a total of 322 ± 117 m. Multiple linear regression proved the differences between HR after 2 min of recovery and baseline HR in pre-TAVI after a 6MWT was the only significant predictor of waking distance improvement during follow-up.

CONCLUSIONS

Our study suggests that analysis of HR recovery after a 6MWT may be a helpful and easy parameter to assess improvements in exercise capacity after TAVI. This simple method can help to identify patients in whom no significant benefit in functional improvement can be expected despite successful valve implantation.

Preprocedural muscle strength and physical performance and the association with functional decline or mortality in frail older patients after transcatheter aortic valve implementation: a systematic review and meta-analysis

BACKGROUND

A significant number of older patients planned for transcatheter aortic valve implantation (TAVI) experience a decline in physical functioning and death, despite a successful procedure.

OBJECTIVE

To systematically review the literature on the association of preprocedural muscle strength and physical performance with functional decline or long-term mortality after TAVI.

METHODS

We followed the PRISMA guidelines and pre-registered this review at PROSPERO (CRD42020208032). A systematic search was conducted in MEDLINE and EMBASE from inception to 10 December 2021. Studies reporting on the association of preprocedural muscle strength or physical performance with functional decline or long-term (>6 months) mortality after the TAVI procedure were included. For outcomes reported by three or more studies, a meta-analysis was performed.

RESULTS

In total, two studies reporting on functional decline and 29 studies reporting on mortality were included. The association with functional decline was inconclusive. For mortality, meta-analysis showed that low handgrip strength (hazard ratio (HR) 1.80 [95% confidence interval (CI): 1.22-2.63]), lower distance on the 6-minute walk test (HR 1.15 [95% CI: 1.09-1.21] per 50 m decrease), low performance on the timed up and go test (>20 s) (HR 2.77 [95% CI: 1.79-4.30]) and slow gait speed (<0.83 m/s) (HR 2.24 [95% CI: 1.32-3.81]) were associated with higher long-term mortality.

CONCLUSIONS

Low muscle strength and physical performance are associated with higher mortality after TAVI, while the association with functional decline stays inconclusive. Future research should focus on interventions to increase muscle strength and physical performance in older cardiac patients.

Transcatheter aortic valve implantation and frailty

Over the last decade, transcatheter aortic valve implantation (TAVI) has emerged as a treatment option for patients with severe aortic stenosis. With exponential increase in the number of TAVI procedures, frailty assessments have been considered important for patients undergoing TAVI, and a number of studies have indicated a relationship between the frailty and post-TAVI outcomes. In this review, using studies searched systematically in the PubMed database, we review important frailty assessment tools that can be used as prognostic factors for patients before TAVI. The assessment tools were categorized as quantitative single marker, semi-quantitative single marker, or quantitative combined marker. Studies were further stratified by whether they used frailty markers to predict patients' prognosis pre-TAVI or to evaluate frailty improvement post-TAVI. The Clinical Frailty Scale (CFS), a semi-quantitative assessment, is one of the frailty assessment tools discussed. It may be easily used even in an outpatient consultation room. The CFS classifies patients' activity into nine categories, based on a simple interview and the patient's appearance. Gait speed and serum albumin levels were considered as qualitative frailty assessment tools. Compared to other methods, the Essential Frailty Toolset had the highest inter-rater reliability for accuracy in predicting mortality, thereby allowing better identification of vulnerable old age people and optimization of outcomes. A few studies have also focused on changes in frailty pre- and post-TAVI. Serum albumin-level measurements are important for assessing the frailty improvement in the chronic phase. Each frailty assessment tool had its own characteristics, strengths, and weaknesses, and therefore, these tools need to be selected based on where they are being used and the patient's condition.

Prognostic Importance of Health Status Versus Functional Status in Heart Failure and Secondary Mitral Regurgitation

OBJECTIVES

This study sought to understand the extent to which health status and exercise capacity are independently associated with long-term outcomes in patients with heart failure (HF) and secondary mitral regurgitation (MR).

BACKGROUND

Secondary MR in patients with HF leads to impaired health status (Kansas City Cardiomyopathy Questionnaire Overall Summary Score [KCCQ-OS]) and exercise capacity (6-minute walk distance [6MWD]), both of which improve after transcatheter mitral valve repair (TMVr).

METHODS

The study used data from the COAPT trial (N = 604) to examine the association of baseline KCCQ-OS and 6MWD with 2-year mortality and HF hospitalization, adjusting for treatment arm and patient factors. We also examined the association of change in KCCQ-OS and 6MWD from baseline to 1 month with risk of outcomes from 1 month to 2 years. Interactions of KCCQ-OS and 6MWD with treatment assignment were explored.

RESULTS

Mean baseline KCCQ-OS was 53 ± 23 points, and 6MWD was 240 ± 125 meters. In models including both measures, greater baseline 6MWD (but not KCCQ-OS) was associated with reduced 2-year mortality (HR per 125 meters: 0.75, 95% CI: 0.61-0.92). When stratified by treatment group, both baseline KCCQ-OS and 6MWD were independently associated with HF hospitalization in patients treated with medical therapy, whereas only KCCQ-OS was associated with HF hospitalization in patients treated with TMVr. In separate analyses, 1-month improvements in KCCQ-OS and 6MWD were each associated with lower subsequent risk of mortality and HF hospitalization, independent of treatment group.

CONCLUSIONS

Among patients with HF and severe secondary MR, assessment of both health status and exercise capacity provide complementary prognostic information for patients with HF and severe secondary MR-both before and after TMVr. (Cardiovascular Outcomes Assessment of the MitraClip Percutaneous Therapy for Heart Failure Patients With Functional Mitral Regurgitation [The COAPT Trial]; NCT01626079).

The Physiological Burden of the 6-Minute Walk Test Compared With Cardiopulmonary Exercise Stress Test in Patients With Severe Aortic Atenosis

BACKGROUND

Management of aortic stenosis (AS) relies on symptoms. Exercise testing is recommended for asymptomatic patients with significant AS but is often experienced as forbidding and/or technically unrealistic for patients who are often frail, deconditioned, and intimidated by the exercise test. We compared the physiological burden assessed with gas exchange assessments to gauge and respiratory exchange ratio (RER) of a 6-minute walk test (6MWT) to a cardiopulmonary exercise stress test (CPET) in patients with severe AS. peak oxygen utilization.

METHODS

Adults with equivocal symptoms and severe AS (1-aortic valve area [AVA] ≤ 1.0 cm2 or AVA index ≤ 0.6 cm2/m2, 2-peak aortic jet velocity ≥ 4.0 m/sec, 3-mean transvalvular pressure gradient ≥ 40 mm Hg by rest or dobutamine stress echocardiography, or 4-aortic valve calcification ≥ 1200 in women or ≥ 2000 AU in men) were studied. All participants completed both a 6MWT and symptom-limited progressive bicycle exercise testing. Breath-by-breath gas analysis and 12-lead electrocardiography were completed during 6MWT and CPET. Results: Eleven patients were studied. Patients walked on average 330 ± 75 m during the 6MWT and achieved a maximal workload of 48 ± 14 watts during the CPET. During the 6MWT, peak maximal oxygen uptake (V ˙ O2peak) was 12.8 ± 2.5 vs 10.8 ± 4.2 mL/kg/min during the CPET. Respiratory exchange ratio exceeded 1.1 in both the 6MWT and CPET indicating similarly high exertion. Compared with the CPET, a larger proportion of the 6MWT was performed at a high intensity level (78% ± 28% vs 33% ± 24% at > 85% V̇O2peak; P = 0.004).

CONCLUSIONS

The 6MWT with breath-by-breath gas analysis was well tolerated and able to achieve a physiological intense RER andV ˙ O2peak that are similar to symptom-limited CPET in patients with severe AS.

Six-minute walk test in cardiac rehabilitation

Six-minute walk test (6MWT) is a simple and safe tool for assessing exercise tolerance in  various  categories  of  patients.  Currently,  6MWT  is  used to assess the functional status of a patient and determine the strategy of increasing physical activity, primarily in patients with reduced exercise tolerance and contraindications for cardiopulmonary exercise  test. The basic requirements for the 6MWT are presented, taking into account the factors affecting its  informativeness  and  accuracy,  as  well  as the interpretation of results. The diagnostic and prognostic value of 6MWT in different categories of patients are discussed. The prospects for 6MWT use in cardiac rehabilitation for planning rehabilitation program, prescribing exercises,  determining  the  risk   of   complications,   and   evaluating the effectiveness  are  considered.  The  limitations  of  6MWT  and  ways to overcome it, as well as directions for further research are presented.

Prognostic Value of 6-Minute Walk Distance in Patients Undergoing Percutaneous Coronary Intervention: a Veterans Affairs Prospective Study

The 6-minute walk distance (6MWD) test is a useful prognostic tool in chronic heart failure. Its usefulness after percutaneous coronary intervention is unknown. In a prospective observational study, patients underwent a 6MWD test within 2 weeks after percutaneous coronary intervention. The primary endpoint was major adverse cardiovascular events (MACE) (death, acute coronary syndrome, and heart failure admission) at one year. Receiver operating characteristic curves and area under the curve were used to determine the 6MWD test's predictive power, and the Youden index was used to measure its effectiveness. A total of 212 patients were enrolled (98% men; mean age, 65 ± 9 yr). Major comorbidities were hypertension in 187 patients (88%), dyslipidemia in 186 (88%), and diabetes mellitus in 95 (45%). Among the 176 patients (83%) who completed the 6MWD test, the incidence of MACE at one year was 22% (acute coronary syndrome in 17%; heart failure admission in 4%; and death in 3%). The area under the curve for MACE was 0.59, and 6MWD was shorter for patients with MACE than for those without (290 vs 326 m; P=0.03). For 39 patients with previous heart failure who completed the 6MWD test, the area under the curve was 0.64 for MACE and 0.78 for heart failure admission. The 6MWD test predicted reasonably well the incidence of MACE one year after percutaneous coronary intervention. In a subgroup of patients with previous heart failure, it fared even better in predicting heart failure admission. Larger studies are needed to confirm these findings.

Association of Smoking Status With Long-Term Mortality and Health Status After Transcatheter Aortic Valve Replacement: Insights From the Society of Thoracic Surgeons/American College of Cardiology Transcatheter Valve Therapy Registry

Background

Smoking is a significant risk factor for aortic stenosis but its impact on clinical and health status outcomes after transcatheter aortic valve replacement (TAVR) has not been described.

Methods and Results

Patients (n=72 165) undergoing TAVR at 457 US sites in the STS/ACC TVT (Society of Thoracic Surgeons/American College of Cardiology Transcatheter Valve Therapy) Registry between November 2011 and June 2016 were categorized at the time of TAVR as current/recent smokers versus prior/nonsmokers. A series of multivariable models examined the association between smoking status and outcomes, including 1‐year mortality, rehospitalization, mean gradient, and health status (measured by the 12‐item Kansas City Cardiomyopathy Questionnaire–Overall Summary Score [KCCQ‐OS]) and in‐hospital outcomes. A total of 4063 patients (5.6%) were smokers. Smokers presented for TAVR at a younger age (75 [68–81] years versus 83 [77–88] years) but with a greater burden of cardiovascular and lung disease. In adjusted models, smoking was associated with lower in‐hospital mortality (relative risk, 0.74; 95% CI, 0.62–0.89 [P=0.001]) but not with in‐hospital stroke/transient ischemic attack or myocardial infarction. Smoking status had no association with postdischarge mortality, stroke, myocardial infarction, or heart failure (HF) but was associated with slightly lower 1‐year KCCQ‐OS scores (2.4‐point lower KCCQ‐OS; 95% CI, −4.6 to −0.2 [P=0.031]) and higher mean aortic valve gradients (11.1 versus 10.2 mm Hg, P<0.001) in adjusted models.

Conclusions

The current/recent smoking rate in US patients with TAVR is 5.6% and smokers present at a younger age for TAVR. Smoking was associated with lower in‐hospital but similar long‐term survival after TAVR, slightly worse long‐term health status, and marginally higher mean aortic valve gradients. Further research is needed to understand the effect of smoking cessation on outcomes.

See Editorial Edelman and Thourani

Long-term effect of exercise training in patients after transcatheter aortic valve implantation: Follow-up of the SPORT:TAVI randomised pilot study

Background Increased exercise capacity favourably influences clinical outcomes after transcatheter aortic valve implantation. In our SPORT:TAVI randomised pilot trial, eight weeks of endurance and resistance training (training group, TG) shortly after transcatheter aortic valve implantation resulted in significantly improved exercise capacity, muscular strength and quality of life compared to usual care (UC). However, the long-term clinical benefits of such an intervention are unknown. Design A randomised controlled trial. Methods SPORT:TAVI participants underwent reassessment of trial endpoints 24 ± 6 months after baseline: maximal oxygen uptake (VO₂peak) and anaerobic threshold (VO₂AT) were assessed with cardiopulmonary exercise testing, muscular strength with one-repetition maximum testing, quality of life with the Kansas City cardiomyopathy and medical outcomes study 12-item short-form health survey questionnaires, and prosthetic aortic valve function with echocardiography. Results Of 27 original participants (TG 13; UC 14; age 81 ± 6 years), more patients had died during follow-up in UC ( n = 5) than in TG ( n = 2; P = 0.165); three further patients (TG 1; UC 2) were unavailable for other reasons. In the remaining patients (TG 10; UC 7), a significant between-group difference in favour of TG was observed for change in VO₂AT from baseline (2.7 ml/min/kg (95% confidence interval 0.8-4.6); P = 0.008), but not for change in VO₂peak (2.1 ml/min/kg (-1.1-5.4); P = 0.178). Changes in muscular strength and quality of life did not differ between groups over time. Overall, prosthetic valve function remained intact in both groups. Conclusions Eight weeks of exercise training shortly after transcatheter aortic valve implantation resulted in preserved long-term improvements in VO₂AT, but not VO₂peak, muscular strength or quality of life compared to usual care. The findings emphasise the importance of ongoing exercise interventions following transcatheter aortic valve implantation to maintain initial improvements long term. Clinical Trial Registration (original trial): Clinicaltrials.gov NCT01935297.

Predictors and Association With Clinical Outcomes of the Changes in Exercise Capacity After Transcatheter Aortic Valve Replacement

BACKGROUND

At present, there are no objective data specifically examining the clinical impact of variations in exercise capacity post-transcatheter aortic valve replacement (TAVR). We describe the changes in exercise capacity between baseline and 6 months post-TAVR, and ascertain factors associated with and clinical implications of a lack of improvement in exercise capacity post-TAVR.

METHODS

A total of 305 patients (mean age, 79±9 years; 44% men; Society of Thoracic Surgeons predicted risk mortality score, 6.7±4.2%) undergoing TAVR completed both baseline and follow-up exercise capacity assessments at 6 months post-TAVR. Exercise capacity was evaluated by the 6-minute walk test (6MWT). Clinical outcomes were compared between patients displaying greater than (n=152; improving group) versus less than (n=153; nonimproving group) the median percentage change in distance walked between baseline and 6-month follow-up examinations. The primary outcome measure was clinical event rates, measured from the 6-month post-TAVR period onward. Further dichotomization according to baseline 6MWT distance (less than versus more than median walking distance, or slow walker versus fast walker) was also assessed.

RESULTS

The mean overall distances walked pre- and post-TAVR (6 months post-TAVR) were 204±119 and 263±116 m, respectively (Δ6MWT=60±106 m), with 219 (72%) patients demonstrating an increase in their walking distance (median percentage increase of the entire population was 20% [interquartile range, 0%-80%]). Factors independently correlated with reduced exercise capacity improvement included a range of baseline clinical characteristics (older age, female sex, chronic obstructive pulmonary disease; P<0.05 for all), periprocedural major or life-threatening bleeding (P=0.009) and new-onset anemia at 6 months post-TAVR (P=0.009). Failure to improve the 6MWT distance by at least 20% was independently associated with all-cause mortality (P=0.002) and cardiovascular death or rehospitalization for cardiovascular causes (P=0.001). Baseline slow walkers who were able to improve the 6MWT distance presented with significantly better outcomes than nonimprovers (P=0.01 for all-cause mortality; P=0.001 for cardiovascular end point).

CONCLUSIONS

Approximately one-third of patients undergoing TAVR did not improve their exercise capacity postprocedure. The lack of functional improvement post-TAVR was predicted by a mix of baseline and periprocedural factors translating into poorer clinical outcomes. These results suggest that systematically implementing exercise capacity assessment pre- and post-TAVR may help to improve patient risk stratification.

Neurological Injury in Intermediate-Risk Transcatheter Aortic Valve Implantation

BACKGROUND

The application of transcatheter aortic valve implantation (TAVI) to intermediate-risk patients is a controversial issue. Of concern, neurological injury in this group remains poorly defined. Among high-risk and inoperable patients, subclinical injury is reported on average in 75% undergoing the procedure. Although this attendant risk may be acceptable in higher-risk patients, it may not be so in those of lower risk.

METHODS AND RESULTS

Forty patients undergoing TAVI with the Edwards SAPIEN-XT™ prosthesis were prospectively studied. Patients were of intermediate surgical risk, with a mean±standard deviation Society of Thoracic Surgeons score of 5.1±2.5% and a EuroSCORE II of 4.8±2.4%; participant age was 82±7 years. Clinically apparent injury was assessed by serial National Institutes of Health Stroke Scale assessments, Montreal Cognitive Assessments (MoCA), and with the Confusion Assessment Method. These identified 1 (2.5%) minor stroke, 1 (2.5%) episode of postoperative delirium, and 2 patients (5%) with significant postoperative cognitive dysfunction. Subclinical neurological injury was assessed using brain magnetic resonance imaging, including diffusion-weighted imaging (DWI) sequences preprocedure and at 3±1 days postprocedure. This identified 68 new DWI lesions present in 60% of participants, with a median±interquartile range of 1±3 lesions/patient and volumes of infarction of 24±19 μL/lesion and 89±218 μL/patient. DWI lesions were associated with a statistically significant reduction in early cognition (mean ΔMoCA -3.5±1.7) without effect on cognition, quality of life, or functional capacity at 6 months.

CONCLUSIONS

Objectively measured subclinical neurological injuries remain a concern in intermediate-risk patients undergoing TAVI and are likely to manifest with early neurocognitive changes.

CLINICAL TRIAL REGISTRATION

URL: http://www.anzctr.org.au. Australian & New Zealand Clinical Trials Registry: ACTRN12613000083796.

Preoperative Frailty Assessment and Outcomes at 6 Months or Later in Older Adults Undergoing Cardiac Surgical Procedures: A Systematic Review

BACKGROUND

Frailty assessment may inform surgical risk and prognosis not captured by conventional surgical risk scores.

PURPOSE

To evaluate the evidence for various frailty instruments used to predict mortality, functional status, or major adverse cardiovascular and cerebrovascular events (MACCEs) in older adults undergoing cardiac surgical procedures.

DATA SOURCES

MEDLINE and EMBASE (without language restrictions), from their inception to 2 May 2016.

STUDY SELECTION

Cohort studies evaluating the association between frailty and mortality or functional status at 6 months or later in patients aged 60 years or older undergoing major or minimally invasive cardiac surgical procedures.

DATA EXTRACTION

2 reviewers independently extracted study data and assessed study quality.

DATA SYNTHESIS

Mobility, disability, and nutrition were frequently assessed domains of frailty in both types of procedures. In patients undergoing major procedures (n = 18 388; 8 studies), 9 frailty instruments were evaluated. There was moderate-quality evidence to assess mobility or disability and very-low- to low-quality evidence for using a multicomponent instrument to predict mortality or MACCEs. No studies examined functional status. In patients undergoing minimally invasive procedures (n = 5177; 17 studies), 13 frailty instruments were evaluated. There was moderate- to high-quality evidence for assessing mobility to predict mortality or functional status. Several multicomponent instruments predicted mortality, functional status, or MACCEs, but the quality of evidence was low to moderate. Multicomponent instruments that measure different frailty domains seemed to outperform single-component ones.

LIMITATION

Heterogeneity of frailty assessment, limited generalizability of multicomponent frailty instruments, few validated frailty instruments, and potential publication bias.

CONCLUSION

Frailty status, assessed by mobility, disability, and nutritional status, may predict mortality at 6 months or later after major cardiac surgical procedures and functional decline after minimally invasive cardiac surgery.

PRIMARY FUNDING SOURCE

National Institute on Aging and National Heart, Lung, and Blood Institute.

Prognostic Usefulness of the 6-Minute Walk Test in Patients With Severe Aortic Stenosis

The 6-minute walk test distance (6MWD) has been shown to predict prognosis in selected cohorts of patients with heart failure and outcomes after surgical or transcatheter aortic valve implantation (AVI) in patients with symptomatic severe aortic stenosis (AS). Our objective was to evaluate the association between the 6MWD and outcome in patients with severe AS while remaining under medical treatment. In a prospective observational cohort study, a total of 149 patients diagnosed with severe AS by Doppler echocardiography underwent a 6-minute walk test. The single end point was a composite of all-cause death or hospitalization for heart failure. Patients receiving an AVI were censored from follow-up at the time of their AVI, so that only the events that occurred while the patients remained under medical treatment were included in the analysis. During follow-up (median 12.9 months), the end point occurred in 65 patients (43.6%). Univariate analysis showed an association between the 6MWD and the end point (p <0.001). After adjustment for symptoms, left ventricular ejection fraction, aortic valve area, Charlson co-morbidity score, and anemia, the 6MWD independently predicted the end point (adjusted hazard ratio 0.63; 95% confidence interval 0.45 to 0.89; p = 0.010). The incidence of the composite end point was 12 per 100 patient-years in patients with a 6MWD >331 m compared to 86 per 100 patient-years in those with a 6MWD ≤331 m (p <0.001). In conclusion, although patients with severe AS remain under medical treatment, the 6MWD is independently associated with all-cause death or hospitalization for heart failure.

Association of Patient-Reported Health Status With Long-Term Mortality After Transcatheter Aortic Valve Replacement: Report From the STS/ACC TVT Registry

BACKGROUND

Although transcatheter aortic valve replacement (TAVR) is an effective treatment for aortic stenosis, long-term mortality after TAVR remains high and challenging to predict. The Kansas City Cardiomyopathy Questionnaire (KCCQ) is a health status measure, assessed directly from patients, that integrates 2 clinically relevant factors (symptoms and functional status) that may predict TAVR outcomes.

METHODS AND RESULTS

Among 7769 patients from 286 sites in the Society of Thoracic Surgeons (STS)/American College of Cardiology (ACC) Transcatheter Valve Therapy (TVT) Registry, we examined the association between preprocedure (baseline) patient health status, as assessed by the KCCQ, and 1-year mortality after TAVR. The KCCQ Overall Summary Score was categorized as very poor: <25, poor: 25 to 49, fair: 50 to 74, or good: ≥75. Before TAVR, health status was rated as very poor in 28%, poor in 38%, fair in 24%, and good in 10%. Patients with worse health status were more likely to be women and had more comorbidities and higher STS mortality risk scores. Compared with those with good health status before TAVR and after adjusting for a broad range of baseline covariates, patients with very poor health status had a 2-fold increased hazard of death over the first year after TAVR (adjusted hazard ratio, 2.00; 95% confidence interval, 1.58-2.54), whereas those with poor and fair health status had intermediate outcomes (adjusted hazard ratio, 1.54; 95% confidence interval, 1.22-1.95 and adjusted hazard ratio, 1.20; 95% confidence interval, 0.94-1.55, respectively).

CONCLUSIONS

In a national, contemporary practice cohort, worse preprocedure patient health status, as assessed by the KCCQ, was associated with greater long-term mortality after TAVR. These results support the measurement and integration of the KCCQ into mortality risk assessments for patients considering TAVR.

Predictors of poor outcomes after transcatheter aortic valve replacement: results from the PARTNER (Placement of Aortic Transcatheter Valve) trial

BACKGROUND

Transcatheter aortic valve replacement (TAVR) is a less invasive option for treatment of high-risk patients with severe aortic stenosis. We sought to identify patients at high risk for poor outcome after TAVR using a novel definition of outcome that integrates quality of life with mortality.

METHODS AND RESULTS

Among 2137 patients who underwent TAVR in the PARTNER (Placement of Aortic Transcatheter Valve) trial or its associated continued access registry, quality of life was assessed with the Kansas City Cardiomyopathy Questionnaire-Overall Summary Scale (KCCQ-OS; range 0-100, where a higher score equates to a better quality of life) at baseline and at 1, 6, and 12 months after TAVR. A poor 6-month outcome (defined as death, KCCQ-OS score <45, or ≥10-point decrease in KCCQ-OS score compared with baseline) occurred in 704 patients (33%). Using a split-sample design, we developed a multivariable model to identify a parsimonious set of covariates to identify patients at high risk for poor outcome. The model demonstrated moderate discrimination (c-index=0.66) and good calibration with the observed data, performed similarly in the separate validation cohort (c-index=0.64), and identified 211 patients (10% of the population) with a ≥50% likelihood of a poor outcome after TAVR. A second model that explored predictors of poor outcome at 1 year identified 1102 patients (52%) with ≥50% likelihood and 178 (8%) with ≥70% likelihood of a poor 1-year outcome after TAVR.

CONCLUSIONS

Using a large, multicenter cohort, we have developed and validated predictive models that can identify patients at high risk for a poor outcome after TAVR. Although model discrimination was moderate, these models may help guide treatment choices and offer patients realistic expectations of outcomes based on their presenting characteristics.

CLINICAL TRIAL REGISTRATION URL

http://www.clinicaltrials.gov. Unique identifier: NCT00530894.

Relation between six-minute walk test performance and outcomes after transcatheter aortic valve implantation (from the PARTNER trial)

Functional capacity as assessed by 6-minute walk test distance (6MWTD) has been shown to predict outcomes in selected cohorts with cardiovascular disease. To evaluate the association between 6MWTD and outcomes after transcatheter aortic valve implantation (TAVI) among participants in the Placement of AoRTic TraNscathetER valve (PARTNER) trial, TAVI recipients (n = 484) were stratified into 3 groups according to baseline 6MWTD: unable to walk (n = 218), slow walkers (n = 133), in whom 6MWTD was below the median (128.5 meters), and fast walkers (n = 133) with 6MWTD >128.5 meters. After TAVI, among fast walkers, follow-up 6MWTD decreased by 44 ± 148 meters at 12 months (p <0.02 compared with baseline). In contrast, among slow walkers, 6MWTD improved after TAVI by 58 ± 126 meters (p <0.001 compared with baseline). Similarly, among those unable to walk, 6MWTD distance increased by 66 ± 109 meters (p <0.001 compared with baseline). There were no differences in 30-day outcomes among 6MWTD groups. At 2 years, the rate of death from any cause was 42.5% in those unable to walk, 31.2% in slow walkers, and 28.8% in fast walkers (p = 0.02), driven primarily by differences in noncardiac death. In conclusion, among high-risk older adults undergoing TAVI, baseline 6MWTD does not predict procedural outcomes but does predict long-term mortality. Nonetheless, patients with poor baseline functional status exhibit the greatest improvement in 6MWTD. Additional work is required to identify those with poor functional status who stand to benefit the most from TAVI.