Editorials
How Should Rehabilitation Be Performed After Transcatheter Aortic Valve Replacement?
2020 年 84 巻 7 号 p. 1055-1056
詳細
2020 年 84 巻 7 号 p. 1055-1056
In Japan’s aging population, medical care for the elderly is a pressing issue because the functioning of the cardiovascular and respiratory systems decreases with age. In the cardiovascular system, there is a decrease in the maximum heart rate, cardiac output, blood flow, responsiveness to movement, increased peripheral vascular resistance, and arteriosclerosis. The respiratory system is characterized in the elderly by decreases in maximal oxygen uptake, ventilation, vital capacity, respiratory muscle strength, arterial oxygen tension, and lung elasticity.1 Therefore, hospitalization of the elderly, regardless of the cause or treatment, leads to a decline in the activities of daily living (ADL). It has been reported that 40–65% of patients with acute disease show a significant decrease in ADL in the days before admission,2 and ≈35–40% of the elderly have a hospital-acquired functional decline at discharge, which increases to 50% in patients aged ≥85 years.3 Factors contributing to the development of hospital-acquired functional decline include pre-disease determinants such as functional reserve, disease severity, and in-hospital processes such as the drug therapy, malnutrition, mobility, characteristics of the hospital environment, and support for independence (Figure).4
Hospital-associated functional decline: The role of hospitalization processes beyond individual risk factors. Adapted with permission from Ziesberg A, et al.4
Article p 1083
In developed countries with long life expectancies such as Japan, the most common cause of aortic stenosis (AS) is age-related degeneration of the aortic leaflets, accounting for more than 80% of severe AS requiring surgery.5 Therefore, the frequency of AS increases with age, the incidence rate of severe AS in patients aged ≥80 years is ≈7%,6 and the occurrence of AS in heart disease is expected to increase. Transcatheter aortic valve replacement (TAVI) was first performed in 2013 Japan as a minimally invasive catheterization therapy with curative intent for patients who cannot undergo or are at high risk for surgical aortic valve replacement (SAVR). Although there are no long-term prognostic data for TAVI compared with SAVR in low-risk patients, several randomized control trials have shown that TAVI is equivalent or better for mid-term outcomes and better for short-term outcomes.7,8
In this issue of the Journal, Saitoh et al9 demonstrate that hospital-acquired functional decline is associated with worse mid-term clinical outcomes in older patients following TAVI and the usefulness of monitoring the trajectory of functional status during hospitalization. To date, the incidence of hospital-acquired functional decline in patients with standard acute-phase cardiac rehabilitation following TAVI has not been clarified. Because the present study was based on a small sample from a single center, the statistical power may be weak to determine clinical outcome and risk factors, which is described as a limitation by the authors. Furthermore, as noted, not only rehabilitation but other factors contribute to functional decline during and after hospitalization, and although the median postoperative hospital stay was as long as 8 days in this study, the number of institutions where TAVI with local anesthesia is performed and the patient is discharged within a few days is increasing. However, the study provides several important clinical implications with regard to the incidence of hospital-acquired functional decline and clinical outcomes following TAVI. First, 113 of 463 patients (24.4%) had hospital-acquired functional decline despite the standard acute-phase cardiac rehabilitation after TAVI. The authors state “a significant proportion”; however, functional decline during hospital stay is defined as between 30% and 50% in previous reports. Moreover, it can be interpreted that even though TAVI, a relatively invasive treatment, was performed, the hospital-acquired functional decline was limited to 24% due to rehabilitation from the acute phase. It may be effective to perform the rehabilitation intervention as a single protocol for a single center, and experience it with a large number of TAVI patients. Second, hospital-acquired decline was significantly associated with all-cause death even after adjusting for multivariate Cox analysis. Although the reason remains unclear in this study, previous studies have shown that functional decline during hospitalization is a key trigger for future disability or death.10 Third, early ambulation was not associated with hospital-acquired functional decline after TAVI, suggesting that comprehensive interventions, including early ambulation and/or a stepwise increase in physical activity, and resistance training are increasingly important for the prevention of hospital-acquired functional decline in older patients undergoing TAVI. In fact, there is no nationwide protocol for rehabilitation after TAVI, and each institution conducts rehabilitation independently. However, as TAVI is not as invasive as SAVR, so rehabilitation with higher load could be performed more actively from an earlier stage. Large-scale, prospective studies investigating whether further rehabilitation can reduce hospital-acquired functional decline after TAVI would give greater clinical perspectives and possible benefits.
With the advent of TAVI, the indications for treatment have expanded, and treatment of AS has become possible even in elderly and high-risk patients. On the other hand, TAVI has been performed in patients with decreased physical activity due to age-related cardiopulmonary function decline even without dementia. Although less invasive than SAVR, rehabilitation is crucial for elderly TAVI patients with an average age of 85 years, in whom hospital-acquired functional decline can decrease by approximately 50% during hospitalization. In fact, the elderly often suffer from unexpected complications, resulting in longer hospital stays. In this study, there was no significant difference in the preoperative conditions of patients with and without hospital-acquired functional decline.9 However, preoperative rehabilitation should be introduced, and the preoperative hospital stay should be shortened as much as possible. Furthermore, not only physical activity improvement, but also total care including maintenance of cognitive function and support for social life after discharge should be provided, and it is necessary to work as “one team” through multidisciplinary cooperation by doctors, physical therapists, pharmacists, nurses, care managers etc.
A.T. has no conflicts of interest to declare. M.O. is a member of Circulation Journal ’ Editorial Team.
