High-intensity interval training in patients with left ventricular assist devices: A pilot randomized controlled trial.

BACKGROUND: Left ventricular assist device (LVAD) implantation is an established treatment for patients with advanced heart failure. To date, studies evaluating the impact of aerobic training in patients with LVADs have focused on moderate-intensity exercise. METHODS: This pilot randomized controlled trial compared the effects of high-intensity interval training (HIIT) with those of moderate-intensity continuous training (MICT) on peak oxygen consumption (V̇O2 peak) in patients with LVADs. Secondary outcomes included 6-minute walk test distance, flow-mediated dilation, and anthropometry. Assessments were conducted at baseline and after 12 weeks of supervised training performed 3 times weekly. Participants were randomized to HIIT (4 sets of 4 minutes at 80%-90% V̇O2 reserve, alternating with 3 minutes at 50%-60% V̇O2 reserve) or MICT groups (28 minutes continuously at 50%-60% V̇O2 reserve). Within and between-group differences were analyzed using linear mixed models. Data are expressed as marginal means with 95% confidence intervals or as mean ± SD. RESULTS: A total of 21 participants were randomized (HIIT: age 57.7 ± 13.1 years; n = 11 and MICT: age 55.6 ± 14.2 years; n = 10) (mean ± SD). No major adverse events occurred in response to training in either group. HIIT significantly improved V̇O2 peak (15.6 [13.2-17.8] to 18.4 [16.0-20.8] ml/kg/min) (marginal mean [95% CI]) compared with MICT (16.2 [13.8-18.7] to 17.2 [14.6-19.7] ml/kg/min; p < 0.05 between groups). No significant group differences were detected in secondary outcomes. CONCLUSION: In patients with LVADs, HIIT was well tolerated and increased aerobic capacity more than MICT. These preliminary findings support the prescription of high-intensity exercise in clinically stable patients with LVADs but warrant validation in a larger sample and across a broader range of physiologic and clinical outcomes. CLINICAL TRIAL REGISTRATION: URL: https://www.anzctr.org.au, unique identifier: ACTRN12616001596493.

Reliability of sternal instability scale (SIS) for transverse sternotomy in lung transplantation (LTX).

A surgical incision for bilateral sequential lung transplantation (BSLTX) is the "clam shell" (CSI) approach via bilateral anterior thoracotomies and a transverse sternotomy to allow for sequential replacement of the lungs. This can be associated with significant post-operative pain, bony overriding or sternal instability. The sternal instability scale (SIS) is a non-invasive manual assessment tool that can be used to detect early bony non-union or instability following CSI; however, its reliability is unknown. OBJECTIVE: This prospective blinded reliability study aimed to assess intra-rater and inter-rater reliability of the SIS following lung transplantation. METHOD: Participants post BSLTX aged older than 18 years underwent sternal assessment utilizing the SIS. Two assessors examined the sternum using a standardized protocol at two separate time points with a test-re-test time of 48 hours. The outcome measure was SIS tool using four categories from 0 (clinically stable) to 3 (separated sternum with overriding). RESULTS: In total, 20 participants (75% female) with a mean age of 48 years (SD 17) and mean pain score of 3 out of 10 were included, 60% having well healed wounds and 25% reporting symptoms of sternal clicking. The most painful self-reported painful activity was coughing. The SIS demonstrated excellent reliability with a kappa = 0.91 by different assessors on the same day, and kappa = 0.83 for assessments by the same assessor on different days. CONCLUSION: The SIS is a reliable manual assessment tool for evaluation of sternal instability after CSI following BSLTX and may facilitate the timely detection and management of sternal instability.

Effect of Upper Limb Rehabilitation Compared to No Upper Limb Rehabilitation in Lung Transplant Recipients: A Randomized Controlled Trial.

OBJECTIVE: To investigate the effect of a supervised upper limb (UL) program (SULP) compared to no supervised UL program (NULP) after lung transplantation (LTx). DESIGN: Randomized controlled trial. SETTING: Physiotherapy gym. PARTICIPANTS: Participants (N=80; mean age, 56±11y; 37 [46%] men) were recruited after LTx. INTERVENTIONS: All participants underwent lower limb strength thrice weekly and endurance training. Participants randomized to SULP completed progressive UL strength training program using handheld weights and adjustable pulley equipment. MAIN OUTCOME MEASURES: Overall bodily pain was rated on the visual analog scale. Shoulder flexion and abduction muscle strength were measured on a hand held dynamometer. Health related quality of life was measured with Medical Outcomes Study 36-item Short Form health Survey and the Quick Dash. Measurements were made at baseline, 6 weeks, 12 weeks, and 6 months by blinded assessors. RESULTS: After 6 weeks of training, participants in the SULP (n=41) had less overall bodily pain on the visual analog scale than did participants in the NULP (n=36) (mean VAS bodily pain score, 2.1±1.3cm vs 3.8±1.7cm; P<.001) as well as greater UL strength than did participants in the NULP (mean peak force, 8.4±4.0Nm vs 6.7±2.8Nm; P=.037). At 12 weeks, participants in the SULP better quality of life related to bodily pain (76±17 vs 66±26; P=.05), but at 6 months there were no differences between the groups in any outcome measures. No serious adverse events were reported. CONCLUSIONS: UL rehabilitation results in short-term improvements in pain and muscle strength after LTx, but no longer-term effects were evident.

Physical Function in Subjects Requiring Extracorporeal Membrane Oxygenation Before or After Lung Transplantation.

BACKGROUND: Extracorporeal membrane oxygenation (ECMO) is used as a rescue therapy before and after lung transplantation, but little is known about functional recovery or complications after ECMO in this cohort. This study aimed to describe early physical function and leg complications in subjects who received ECMO before or after lung transplantation, and to compare functional outcomes to a matched cohort of subjects who did not require ECMO. METHODS: A retrospective study was conducted over 2 years. Highest mobility level was assessed, in both the ECMO and non-ECMO groups, prior to ICU admission, at ICU discharge, and at hospital discharge, while 6-min walk distance was measured at hospital discharge and at 3 months. Strength was assessed at ICU discharge and at hospital discharge in the ECMO subjects only, and leg complications were recorded up until hospital discharge. RESULTS: 17 subjects (mean age 43 ± 13 y; 65% (11 of 17 subjects) female) required ECMO before or after lung transplant. Survival to hospital discharge was 82% (14 of 17 subjects). At ICU discharge, strength and mobility levels were poor, but both improved by hospital discharge (P < .001). Leg complications were reported in 50% of survivors (7 of 14 subjects). ECMO survivors spent longer in the ICU (P < .001) and hospital (P = .002) and had worse physical function (ie, lower mobility level at ICU discharge, mean difference -1, P = .02; 6-min walk distance at hospital discharge: mean difference -99 m, P = .004) than lung transplant recipients not requiring ECMO (n = 28). CONCLUSIONS: In subjects requiring ECMO before or after lung transplantation, 82% survived to hospital discharge, but leg complications were common and physical function was poor at ICU discharge. Physical function improved over time, however subjects who required ECMO had a longer period of hospitalization and worse physical function at ICU and hospital discharge than those who did not require ECMO.

Longer Versus Shorter Duration of Supervised Rehabilitation After Lung Transplantation: A Randomized Trial.

OBJECTIVE: To investigate the effects of a supervised longer- (14wk) versus shorter-duration (7wk) rehabilitation program after lung transplantation (LTX). DESIGN: Randomized controlled trial. SETTING: Outpatient rehabilitation gym setting. PARTICIPANTS: Post-LTX patients aged ≥18 years (N=66; 33 women; mean age, 51±13y) who had undergone either single LTX or bilateral LTX. INTERVENTION: Outpatient rehabilitation program consisting of thrice-weekly sessions with cardiovascular training on bike ergometer and treadmill plus upper and lower limb strength training. MAIN OUTCOME MEASURES: Measures were taken at baseline, 7 weeks, 14 weeks, and 6 months by assessors who were blinded to group allocation. Functional exercise capacity was measured by the 6-minute walk test (6MWT). Strength of quadriceps and hamstrings was measured on an isokinetic dynamometer and recorded as average peak torque of 6 repetitions for both muscles. Quality of life (QOL) was assessed with the Medical Outcomes Study 36-Item Short-Form Health Survey. RESULTS: Of the participants, 86% had bilateral LTX and 41% had primary diagnosis of chronic obstructive pulmonary disease. The 6MWT increased in both groups with no significant difference between groups at any time point (mean 6mo 6MWD: short, 590±85m vs long, 568±127m; P=0.5). Similarly, at 6 months, there was no difference between groups in quadriceps average peak torque (mean, 115±38Nm vs 114±40Nm, respectively; P=.59), hamstring average peak torque (57±18Nm vs 52±19Nm, respectively; P=.36), or mental or physical health domains of quality of life. CONCLUSIONS: Shorter duration (7wk) of rehabilitation achieves comparable outcomes with 14 weeks of supervised rehabilitation for functional exercise capacity, lower limb strength, and quality of life at 6 months after LTX.

Physical function after extracorporeal membrane oxygenation in patients pre or post heart transplantation - An observational study.

OBJECTIVE: To describe physical function, leg complications and health-related quality of life (HRQOL) in the three months following extracorporeal membrane oxygenation (ECMO) pre- or post-heart transplantation (HTx). BACKGROUND: Little is known about functional recovery following ECMO before or after HTx. METHODS: A 2-year retrospective study in patients who received ECMO pre or post HTx. Strength, mobility, leg complications and HRQOL were recorded to hospital discharge. Six-minute walk distance (6MWD) was assessed at hospital discharge and 3 months. RESULTS: 25 patients were included, with 80% (20/25) survival to hospital discharge. At ICU discharge, strength and mobility were poor but improved by hospital discharge (p < 0.001) despite leg complications in 44% (11/25) of patients. The 6MWD improved over time (mean 203 m, 95% confidence interval 140-265). HRQOL scores were lower than Australian norms (p < 0.05). CONCLUSION: Patients requiring ECMO pre or post HTx had impaired physical function at ICU discharge and leg complications were common.