Exercise Stress Testing After Stroke or Transient Ischemic Attack: A Scoping Review

Adverse Events During Submaximal Aerobic Exercise Testing in People With Subacute Stroke: A Scoping Review

BACKGROUND AND PURPOSE

Concern for adverse cardiovascular events and limited guidance regarding how to conduct aerobic exercise (AEx) testing for individuals poststroke are key barriers to implementation by physical therapists in stroke rehabilitation. This study aimed to describe the nature and safety of submaximal AEx testing protocols for people with subacute stroke (PwSS) and the nature of comorbidity of PwSS who underwent submaximal AEx testing.

METHODS

We conducted a scoping review and searched MEDLINE, EMBASE, PsycINFO, CINAHL, and SPORTDiscus from inception to October 29, 2020. Studies involving submaximal AEx testing with PwSS, reporting on participant comorbidity and on adverse events during testing, were eligible. Two reviewers independently conducted title and abstract and full-text screening. One reviewer extracted data; a second reviewer verified data.

RESULTS

Thirteen studies involving 452 participants and 19 submaximal AEx testing protocols (10 field test, 7 incremental, and 2 constant load) were included. Hypertension (41%), diabetes (31%), and dyslipidemia (27%) were the most common comorbidities reported. No protocols resulted in a serious adverse event. The most common test termination criterion was a heart rate (HR) limit (9 protocols); a limit of 85% age-predicted maximal HR (APM-HR) most frequently reported. Average APM-HR achieved, computed using mean age and mean peak HR, ranged from 59% to 88% across 13 protocols.

DISCUSSION AND CONCLUSION

Diverse submaximal AEx testing protocols with conservative test termination criteria can be safely implemented with PwSS. Results can inform clinical practice guidelines and address physical therapists' concerns with the occurrence of serious adverse events during submaximal AEx testing.Video Abstract available for more insights from the authors (see the Video, Supplemental Digital Content 1 available at: http://links.lww.com/JNPT/A430 ).

A 3-minute recumbent stepper test in chronic stroke

BACKGROUND

Persons with stroke often have difficulty achieving target heart rate (HR) during graded exercise testing (GXT), which is known to limit test sensitivity for detecting clinically relevant cardiac conditions. A novel Recumbent Stepper 3-minute (RS 3Min) "all out" test may increase sensitivity of stress testing after stroke.

OBJECTIVE

To determine the feasibility of adding the RS 3Min test after GXT among persons after stroke.

DESIGN

A within-participant, nonrandomized, repeated measures design.

SETTING

Rehabilitation research laboratory and cardiovascular stress laboratory PARTICIPANTS: Fifteen participants with chronic stroke (56.7 ± 9.6 years; 6.4 ± 4.3 years post stroke; 8 male).

INTERVENTIONS

All participants randomly completed (1) a symptom-limited treadmill GXT and (2) a symptom-limited RS GXT followed by RS 3Min critical power test.

MAIN OUTCOME MEASURES

HR, ratings of perceived exertion, oxygen consumption, respiratory exchange ratio, and power output measured continuously during each test. Blood pressure measured every 2 minutes and or immediately post exercise. P value set at p < .05 from omnibus test for a significant difference among protocols.

RESULTS

The RS 3Min test had a significantly higher rate of achieving target HR compared to the RS GXT (9/14 vs 4/14, p = .02) and was not significantly different from the treadmill GXT (9/14 vs 5/14, p = .09). Minimum power output during the RS 3Min was significantly higher than peak power output during the RS GXT (110 ± 41 W vs. 84 ± 22 W, p = .02) with 12/15 participants reaching a VO2 plateau.

CONCLUSIONS

Although additional studies with randomized designs are needed, a novel RS 3Min "all out" test appears to be a promising method for enhancing test sensitivity in cardiovascular screening after stroke, while providing a potentially valid measure of critical power.

The safety and feasibility of early cardiorespiratory fitness testing after stroke

BACKGROUND

Cardiorespiratory fitness testing is recommended as part of a pre-exercise evaluation to aid the programming of safe, tailored cardiorespiratory fitness training after stroke. But there is limited evidence for its safety and feasibility in people with stroke with varying impairment levels in the early subacute phase of stroke recovery.

OBJECTIVE

To assess the safety and feasibility of cardiorespiratory fitness testing in the early subacute phase after stroke.

DESIGN

A sub-study of a larger single service, multi-site, prospective cohort feasibility study (Cardiac Rehabilitation in Stroke Survivors to Improve Survivorship [CRiSSIS]).

SETTING

Private subacute inpatient rehabilitation facilities.

PARTICIPANTS

Consecutive admissions of people with ischemic stroke admitted to subacute rehabilitation facilities.

INTERVENTION

Not applicable.

MAIN OUTCOME(S)

Safety was determined by the occurrence of adverse or serious adverse events. Feasibility was determined by assessing the (1) number of participants recruited and (2) number of participants able to complete the fitness test.

RESULTS

Between April 2018 and December 2019, a total of 165 people with stroke were screened to participate; 109 were eligible and 65 were recruited. Of the 62 who completed testing, 41 participants were able to complete a submaximal fitness test at a median of 12 days post-stroke. One minor adverse event was recorded. Of the 21 participants unable to complete the fitness test; 4 declined to complete the test, 9 were unable to commence the test, and 8 were unable to complete the first stage of the protocol due to stroke-related impairments. Participants with mild stroke, greater motor and cognitive function, and fewer depressive symptoms were more likely to be able to complete the cardiorespiratory fitness test.

CONCLUSION

Cardiorespiratory fitness testing was safe for most people with mild-to-moderately severe ischemic stroke and transient ischemic attack in the early subacute phase, but only two-thirds of the participants could complete the test.

The relationship between relative aerobic load, energy cost, and speed of walking in individuals post-stroke

BACKGROUND

Individuals post-stroke walk slower than their able-bodied peers, which limits participation. This might be attributed to neurological impairments, but could also be caused by a mismatch between aerobic capacity and aerobic load of walking leading to an unsustainable relative aerobic load at most economic speed and preference for a lower walking speed.

RESEARCH QUESTION

What is the impact of aerobic capacity and aerobic load of walking on walking ability post-stroke?

METHODS

Forty individuals post-stroke (more impaired N = 21; preferred walking speed (PWS)<0.8 m/s, less impaired N = 19), and 15 able-bodied individuals performed five, 5-minute treadmill walking trials at 70 %, 85 %, 100 %, 115 % and 130 % PWS. Energy expenditure (mlO₂/kg/min) and energy cost (mlO₂/kg/m) were derived from oxygen uptake (V˙O₂). Relative load was defined as energy expenditure divided by peak aerobic capacity (%V˙O₂peak) and by V˙O₂ at ventilatory threshold (%V˙O₂-VT). Relative load and energy cost at PWS were compared with one-way ANOVA's. The effect of speed on these parameters was modeled with Generalized Estimating Equations.

RESULTS

Both more and less impaired individuals post-stroke showed lower PWS than able-bodied controls (0.44 [0.19-0.76] and 1.04 [0.81-1.43] vs 1.36 [0.89-1.53] m/s) and higher relative load at PWS (50.2 ± 14.4 and 51.7 ± 16.8 vs 36.2 ± 7.6 %V˙O₂peak and 101.9 ± 20.5 and 97.0 ± 27.3 vs 64.9 ± 13.8 %V˙O₂-VT). Energy cost at PWS of more impaired (0.30 [.19-1.03] mlO₂/kg/m) was higher than less-impaired (0.19[0.10-0.24] mlO₂/kg/m) and able-bodied (0.15 [0.13-0.18] mlO₂/kg/m). For post-stroke individuals, increasing walking speed above PWS decreased energy cost, but resulted in a relative load above endurance threshold.

SIGNIFICANCE

Individuals post-stroke seem to reduce walking speed to prevent unsustainably high relative aerobic loads at the expense of reduced economy. When aiming to improve walking ability post-stroke, it is important to consider training aerobic capacity.

The Use of Samsung Health and ECG M-Trace Base II Applications for the Assessment of Exercise Tolerance in the Secondary Prevention in Patients after Ischemic Stroke

Background and objectives: The aim of the study was to use the mobile application Samsung Health for the assessment of parameters of exercise tolerance and the ECG (electrocardiogram) M-Trace Base II for the assessment of cardiological parameters. Materials and Methods: The measurements were conducted during rest and after performing SMWT (Six Minute Walk Test) and SCT (Stair Climb Test) in 26 patients after ischemic stroke (IS) and 26 healthy individuals. Results: In the SMWT, the post-stroke group (SG) walked a shorter distance (p < 0.001), achieving lower mean gait velocity (p < 0.001) and lower maximum gait velocity (p = 0.002). In the SCT, SG achieved a lower mean gait velocity (p < 0.001) and lower maximum gait velocity (p < 0.001) when compared to the control group (CG). In SG, myocardial ischemia in ECG was noted in four patients after SMWT and in three patients following SCT. Both in SG and in CG the increase in SBP (systolic blood pressure) value measured after SMWT and SCT compared to at rest (p < 0.001) was observed. In SG, in the compared ratios rest to SMWT and SCT as well as SMWT to SCT, there was an increase in HR (heart rate) (p < 0.001). Conclusions: ECG M-Trace Base II and Samsung Health are mobile applications that can assess cardiological parameters and exercise tolerance parameters in patients after IS, so they can be used to plan the intensity of exercise in rehabilitation programs.

Effects of detraining on cardiorespiratory fitness of individuals with chronic stroke

BACKGROUND

Aerobic training can improve cardiorespiratory fitness in individuals after stroke. However, the effects of short-term and long-term detraining are not well known.

OBJECTIVE

To determine the effects of short-term (1-month) and long-term (6-month) detraining on cardiorespiratory fitness (VO_2peak) of individuals after stroke, who participated in aerobic training.

METHODS

A cohort study was developed. Twenty adults (57 ± 11 years old) with stroke were included. After completing an outpatient aerobic training, participants were divided into gain group (VO_2peak increase >1.3 ml.kg^-1.min^-1 from before to immediately after the training) or non-gain group (VO_2peak change ≤1.3 ml.kg^-1.min^-1). Cardiorespiratory fitness (VO_2peak), obtained by the cardiopulmonary exercise test was assessed one and 6 months after the end of the training (short- and long-term detraining, respectively), or collected retrospectively from patient chart (before and after the training).

RESULTS

There was found a significant interaction effect (time*group) for VO_2peak (F= 6.108;p < 0,001). Higher values in the VO_2peak observed in the gain group with the aerobic training (F = 25.86; p< .001) were significantly reduced with short-term detraining, reaching values similar to that observed before the training and to that of the non-gain group (F = 14.81;p= .001). Both groups had similar VO_2peak values within long-term detraining (F = 2.70;p= .12), with no significant differences from the values observed before the training and after short-term detraining (0.11 ≤ p≤ 1.00).

CONCLUSIONS

Detraining on cardiorespiratory fitness of individuals after chronic stroke occurred within only 1 month. Therefore, it is important to maintain aerobic training throughout life.

Determining Safe Participation in Aerobic Exercise Early After Stroke Through a Graded Submaximal Exercise Test

OBJECTIVE

The benefits of aerobic exercise early after stroke are well known, but concerns about cardiovascular risk are a barrier to clinical implementation. Symptom-limited exercise testing with electrocardiography (ECG) is recommended but not always feasible. The purpose of this study was to determine the frequency of and corresponding exercise intensities at which ECG abnormalities occurred during submaximal exercise testing that would limit safe exercise prescription beyond those intensities.

METHODS

This study was a retrospective analysis of ECGs from 195 patients who completed submaximal exercise testing during stroke rehabilitation. A graded submaximal exercise test was conducted with a 5- or 12-lead ECG and was terminated on the basis of predetermined endpoint criteria (heart rate, perceived exertion, signs, or symptoms). ECGs were retrospectively reviewed for exercise-induced abnormalities and their associated heart rates.

RESULTS

The peak heart rate achieved was 65.4% (SD = 10.5%) of the predicted maximum heart rate or 29.1% (SD = 15.5%) of the heart rate reserve (adjusted for beta-blocker medications). The test was terminated more often because of perceived exertion (93/195) than because of heart rate limits (60/195). Four patients (2.1%) exhibited exercise-induced horizontal or downsloping ST segment depression of ≥1 mm. Except for 1 patient, the heart rate at test termination was comparable with the heart rate associated with the onset of the ECG abnormality.

CONCLUSION

A graded submaximal exercise test without ECG but with symptom monitoring and conservative heart rate and perceived exertion endpoints may facilitate safe exercise intensities early after stroke. Symptom-limited exercise testing with ECG is still recommended when progressing to higher intensity exercise.

IMPACT

Concerns about cardiovascular risk are a barrier to physical therapists implementing aerobic exercise in stroke rehabilitation. This study showed that, in the absence of access to exercise testing with ECG, submaximal testing with conservative heart rate and perceived exertion endpoints and symptom monitoring can support physical therapists in the safe prescription of aerobic exercise early after stroke.

LAY SUMMARY

It is recommended that people with stroke participate in aerobic exercise as early as possible during their rehabilitation. A submaximal exercise test with monitoring of heart rate, perceived exertion, blood pressure, and symptoms can support physical therapists in safely prescribing that exercise.

Stroke Prevention Rehabilitation Intervention Trial of Exercise (SPRITE) - a randomised feasibility study

BACKGROUND

The value of cardiac rehabilitation (CR) after a transient ischaemic attack (TIA) or minor stroke is untested despite these conditions sharing similar pathology and risk factors to coronary heart disease. We aimed to evaluate the feasibility of conducting a trial of an adapted home-based CR programme, 'The Healthy Brain Rehabilitation Manual', for patients following a TIA/minor stroke, participants' views on the intervention and, to identify the behaviour change techniques (BCTs) used.

METHODS

Clinicians were asked to identify patients attending the Ulster Hospital, Belfast within 4 weeks of a first TIA or minor stroke. Those who agreed to participate underwent assessments of physical fitness, cardiovascular risk, quality of life and mental health, before random allocation to: Group (1) standard/usual care; (2) rehabilitation manual or (3) manual plus pedometer. All participants received telephone support at 1 and 4 weeks, reassessment at 6 weeks and an invitation to a focus group exploring views regarding the study. Two trained review authors independently assessed the manual to identify the BCTs used.

RESULTS

Twenty-eight patients were invited to participate, with 15 (10 men, 5 women; 9 TIA, 6 minor stroke; mean age 69 years) consenting and completing the study. Mean time to enrolment from the TIA/stroke was 20.5 days. Participants completed all assessment measures except VO2max testing, which all declined. The manual and telephone contact were viewed positively, as credible sources of advice. Pedometers were valued highly, particularly for goal-setting. Overall, 36 individual BCTs were used, the commonest being centred around setting goals and planning as well as social support.

CONCLUSION

Recruitment and retention rates suggest that a trial to evaluate the effectiveness of a novel home-based CR programme, implemented within 4 weeks of a first TIA/minor stroke is feasible. The commonest BCTs used within the manual revolve around goals, planning and social support, in keeping with UK national guidelines. The findings from this feasibility work have been used to further refine the next stage of the intervention's development, a pilot study.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT02712385 . This study was registered prospectively on 18/03/2016.

Interval circuit training for cardiorespiratory fitness is feasible for people after stroke

Aims:

To determine if community-dwelling stroke survivors can achieve exercise intensities sufficient to improve cardiorespiratory fitness during a single session of circuit training using an interval training approach.

Methods:

Thirteen independently ambulant participants within 1 year of stroke were included in this observational study (females=54%; median age=65.6 years; interquartile range=23.9). Exercise intensities were assessed throughout an individually tailored circuit of up to seven 5-minute workstations from a selection of nine functional (e.g. walking, stairs, balance) and three ergometer (upright cycle, rower, treadmill) workstations. The interval durations ranged from 5–60 seconds. Oxygen consumption (VO2) was recorded continuously using a portable metabolic system. The average VO2 during each 30-second epoch was determined. VO2≥10.5 mL/kg/min was categorised as ≥moderate intensity.

Findings:

Participants exercised at VO2≥10.5 mL/kg/min for the majority of the time on the workstations [functional: 369/472 epochs (78%), ergometer: 170/204 epochs (83%)]. Most (69%) participants exercised for ≥30 minutes. No serious adverse events occurred.

Conclusions:

Applying interval training principles to a circuit of functional and ergometer workstations enabled ambulant participants to exercise at an intensity and for a duration that can improve cardiorespiratory fitness. The training approach appears feasible, safe and a promising way to incorporate both cardiorespiratory fitness and functional training into post-stroke management.

Prescribing Aerobic Exercise Intensity without a Cardiopulmonary Exercise Test Post Stroke: Utility of the Six-Minute Walk Test

BACKGROUND

The cardiopulmonary exercise test (CPET) is an established method for determining target exercise training intensity (ventilatory threshold [VAT]) and cardiovascular risk; unfortunately, CPET is not readily accessible to people post stroke. The objective of this study was to determine the utility of the 6-minute walk test (6MWT) as a less resource-intensive alternative to CPET for prescribing exercise intensity to people post stroke with motor impairments.

METHODS

Sixty participants (male, 71.7%; 13.5 ± 22.5 [mean ± standard deviation] months post stroke; age 64.5 ± 12.5 years, with a Chedoke-McMaster Stroke Assessment score of 4.9 ± .9 of the leg) underwent 6MWT, CPET, balance, strength, and cognition assessments.

RESULTS

6MWT heart rate (hr) was significantly lower than VAT-hr (92.3 ± 14.8 beats⋅min(-1) versus 99.8 ± 15.7 beats⋅min(-1), respectively, P < .001; correlation r = .7, P < .001). Bland-Altman analysis revealed that the 6MWT underestimated the VAT-hr by 7.7 ± 11.5%. The 95% confidence interval of the mean bias was large (14.8% and -30.3%), reflecting poor agreement, with 71.7% (n = 43) of the participants unable to reach a walking intensity at or above the VAT-hr. Lower oxygen uptake at the VAT (β = .655, P = .004), higher 6MWT-hr (β = 1.07, P = .01), and better balance (β = 1.128, P = .04) were associated with greater utility of the 6MWT for prescribing exercise.

CONCLUSIONS

The 6MWT-hr was not interchangeable with the target training VAT-hr determined by CPET. However, in combination with CPET, the 6MWT will indicate when deficits preclude walking alone as the primary exercise modality for optimizing cardiovascular fitness. Future studies to develop a less resource-intensive, multimodal alternative to the CPET for prescribing exercise are needed. A modality that minimizes the effect of stroke deficits, specifically poor balance, should be included.