Factors Determining the Functional State of Cardiac Surgery Patients with Complicated Postoperative Period

Myocardial Work Assessment in Patients after Coronary Artery Bypass Grafting during Cardiac Rehabilitation

BACKGROUND

Myocardial work is an innovative echocardiographic tool to assess left ventricular performance. Emerging data have shown the added value of this method for evaluating cardiac function compared to traditional echocardiographic parameters and global longitudinal strain. However, few studies are present in the literature about the role of myocardial work during cardiac rehabilitation. Our aim was to assess the impact of a rehabilitation program on myocardial work indices in patients with preserved left ventricular ejection fraction and after coronary artery bypass grafting. In addition, we assessed the correlation between baseline myocardial work indices and their change after cardiac rehabilitation, establishing an optimal cut-off value to predict the improvement.

METHODS

An observational, single-center, and prospective study was conducted. We enrolled patients referred to cardiac rehabilitation after coronary artery bypass grafting and with preserved left ventricular ejection fraction. Before and after the cardiac rehabilitation program, a comprehensive patient assessment was performed, including traditional transthoracic echocardiography, myocardial work analysis, and a six-minute walk test.

RESULTS

Eighty-four patients were enrolled; the mean age was 67.96 (±7.42) years and 78.6% were male. The left ventricular ejection fraction was preserved in all patients, and the global longitudinal strain was -16.18 ± 2.55%, the global work index was 1588.56 ± 345 mmHg%, the global constructive work was 1771.27 ± 366.36 mmHg%, the global wasted work was 105.8 ± 72.02 mmHg%, and the global work efficiency was 92.63 ± 3.9% at baseline. After the cardiac rehabilitation program, the global work index, the global constructive work, and the six-minute walk test improved significantly (1588.56 ± 345 vs. 1960.2 ± 377.03 mmHg%, p-value < 0.001; 1771.27 ± 366.36 vs. 2172.01 ± 418.73 mmHg%, p-value < 0.001; 70.71 ± 40.2 vs. 437.5 ± 108.70 m, p-value < 0.001, respectively).

CONCLUSIONS

Myocardial work indices, specifically global work index and global constructive work, improve after cardiac rehabilitation program in patients undergoing coronary artery bypass grafting with preserved left ventricular ejection fraction.

A randomised controlled trial of prehabilitation in patients undergoing elective cardiac surgery

The feasibility, safety and efficacy of prehabilitation in adult patients awaiting elective cardiac surgery are unknown. A total of 180 participants undergoing elective cardiac surgery were allocated randomly to receive either standard pre-operative care or prehabilitation, consisting of pre-operative exercise and inspiratory muscle training. The primary outcome was change in six-minute walk test distance from baseline to pre-operative assessment. Secondary outcomes included change in inspiratory muscle strength (maximal inspiratory pressure); sarcopenia (handgrip strength); quality of life and compliance. Safety outcomes were pre-specified surgical and pulmonary complications and adverse events. All outcomes were assessed at baseline; at pre-operative assessment; and 6 and 12 weeks following surgery. Mean (SD) age was 64.7 (10.2) years; 33/180 (18%) were women. In total, 65/91 (71.4%) participants who were allocated to prehabilitation attended at least four of eight supervised in-hospital exercise classes; participants aged > 50 years were more likely than younger participants to attend (odds ratio (95%CI) of 4.6 (1.0-25.1)). Six-minute walk test was not significantly different between groups (mean difference (95%CI) -7.8 m (-30.6-15.0), p = 0.503) in the intention-to-treat analysis. Subgroup analyses based on tests for interaction indicated improvements in six-minute walk test distance were larger amongst sarcopenic patients in the prehabilitation group (p = 0.004). Change in maximal inspiratory pressure from baseline to all time-points was significantly greater in the prehabilitation group, with the greatest mean difference (95%CI) observed 12 weeks after surgery (10.6 cmH₂ O (4.6-16.6) cmH₂ O, p < 0.001). There were no differences in handgrip strength or quality of life up to 12 weeks after surgery. There was no significant difference in postoperative mortality (one death in each group), surgical or pulmonary complications. Of 71 pre-operative adverse events, six (8.5%) were related to prehabilitation. The combination of exercise and inspiratory muscle training in a prehabilitation intervention before cardiac surgery was not superior to standard care in improving functional exercise capacity measured by six-minute walk test distance pre-operatively. Future trials should target patients living with sarcopenia and include inspiratory muscle strength training.

Utility of Cardiac Rehabilitation for Long-Term Outcomes in Patients with Hospital-Acquired Functional Decline after Cardiac Surgery: A Retrospective Study

Hospital-acquired functional decline is an important outcome that affects the long-term prognosis of patients after cardiac surgery. Phase II cardiac rehabilitation (CR) for outpatients is expected to improve prognosis; however, this is not clear in patients with hospital-acquired functional decline after cardiac surgery. Therefore, this study evaluated whether phase II CR improved the long-term prognosis of patients with hospital-acquired functional decline after cardiac surgery. This single-center, retrospective observational study included 2371 patients who required cardiac surgery. Hospital-acquired functional decline occurred in 377 patients (15.9%) after cardiac surgery. The mean follow-up period was 1219 ± 682 days in all patients, and there were 221 (9.3%) cases with major adverse cardiovascular events (MACE) after discharge during the follow-up period. The Kaplan-Meier survival curves indicated that hospital-acquired functional decline and non-phase II CR was associated with a higher incidence of MACE than other groups (log-rank, p < 0.001), additionally exhibiting prognosticating MACE in multivariate Cox regression analysis (HR, 1.59; 95% CI, 1.01-2.50; p = 0.047). Hospital-acquired functional decline after cardiac surgery and non-phase II CR were risk factors for MACE. The participation in phase II CR in patients with hospital-acquired functional decline after cardiac surgery could reduce the risk of MACE.

Prehabilitation in elective patients undergoing cardiac surgery: a randomised control trial (THE PrEPS TRIAL) - a study protocol

INTRODUCTION

Prehabilitation prior to surgery has been shown to reduce postoperative complications, reduce length of hospital stay and improve quality of life after cancer and limb reconstruction surgery. However, there are minimal data on the impact of prehabilitation in patients undergoing cardiac surgery, despite the fact these patients are generally older and have more comorbidities and frailty. This trial will assess the feasibility and impact of a prehabilitation intervention consisting of exercise and inspiratory muscle training on preoperative functional exercise capacity in adult patients awaiting elective cardiac surgery, and determine any impact on clinical outcomes after surgery.

METHODS AND ANALYSIS

PrEPS is a randomised controlled single-centre trial recruiting 180 participants undergoing elective cardiac surgery. Participants will be randomised in a 1:1 ratio to standard presurgical care or standard care plus a prehabilitation intervention. The primary outcome will be change in functional exercise capacity measured as change in the 6 min walk test distance from baseline. Secondary outcomes will evaluate the impact of prehabilitation on preoperative and postoperative outcomes including; respiratory function, health-related quality of life, anxiety and depression, frailty, and postoperative complications and resource use. This trial will evaluate if a prehabilitation intervention can improve preoperative physical function, inspiratory muscle function, frailty and quality of life prior to surgery in elective patients awaiting cardiac surgery, and impact postoperative outcomes.

ETHICS AND DISSEMINATION

A favourable opinion was given by the Sheffield Research Ethics Committee in 2019. Trial findings will be disseminated to patients, clinicians, commissioning groups and through peer-reviewed publication.

TRIAL REGISTRATION NUMBER

ISRCTN13860094.