The inclusion period of the randomised controlled trial (RCT) spanned from March 2018 to June 2021. The results from the primary outcome of the clinical trial were submitted for publication.
From a total of 160 patients included in the RCT, we selected 68 patients with severe valve disease for this secondary analysis. Among them, 20 and 14 patients with severe AoS and MR, respectively, were allocated to the prehabilitation group. On the other hand, 20 and 14 patients with severe AoS and MR, respectively, were allocated to the control group.
Baseline clinical characteristics and demographics of patients included in the prehabilitation group are summarized in Table 1. Patients with AoS had better left systolic ventricular function and a lower prevalence of atrial fibrillation compared to MR group. Although non-statistically significant, patients with AoS showed better related physical function parameters (i.e., DASI, VO2peak, ET, and hand-grip) and were less sedentary (YPAS) compared to MR patients.
Comparing prehabilitation vs. control groups, there were no differences at the time of inclusion (Additional file 1).
Table1. Baseline clinical characteristics and demographics of patients included in the multimodal prehabilitation program.
|
AoS (n=20)
|
MR (n=14)
|
P-value
|
Age (yr)
|
72±12
|
69±10
|
0.532
|
Male
|
15 (75)
|
9 (64)
|
0.382
|
NYHA III to IV
|
3 (15)
|
3 (21)
|
0.901
|
FEV1 (% predicted)
|
84±19
|
85±17
|
0.816
|
LVEF (%)
|
61±7
|
55±8
|
0.022
|
PHT
|
0 (0)
|
2 (14)
|
0.162
|
AFib
|
2 (10)
|
6 (43)
|
0.035
|
Euroscore II (score)
|
1.7±1.7
|
2.0±1.2
|
0.644
|
Use of beta-blocker
|
8 (40)
|
7 (50)
|
0.410
|
Charlson (score)
|
3.8±2.3
|
4.1±2.1
|
0.727
|
CSHA (score)
|
3.3±1.2
|
3.4±1.2
|
0.846
|
DASI (score)
|
33.5±16.6
|
23.2±11.4
|
0.054
|
YPAS (score)
|
40.9±22.3
|
32.3±12.2
|
0.199
|
VO2 peak (mL/Kg/min)
|
16.4±5.1
|
13.9±4.0
|
0.151
|
ET (sec)
|
332±111
|
278±117
|
0.179
|
6MWT (m)
|
468±86
|
470±79
|
0.926
|
HG dominant (Kg)
|
30±10
|
28±10
|
0.594
|
30”STS (repetitions)
|
13±4
|
12±3
|
0.359
|
Data are presented as mean ± SD or n (%), as appropriate.
Abbreviations: AFib: atrial fibrillation; CSHA: Canadian Study of Health and Aging clinical frailty scale; DASI: Duke activity status index; ET: endurance time; FEV1: forced expiratory volume in 1 second; HG: hand-grip; LVEF: left ventricular ejection fraction; NYHA: New York heart association classification; PHT: pulmonary hypertension; STS: sit-to-stand test; VO2: oxygen consumption; YPAS: Yale physical activity survey; 6MWT: 6-minute walk test.
The mean adherence to prehabilitation program was over 80% (i.e., percentage of completion of the scheduled training sessions) and mean duration of the prehabilitation program was 7 weeks. The impact of the prehabilitation program on functional capacity was measured for patients with severe AoS (Table 2) and severe MR (Table 3). After completing the prehabilitation program, the functional capacity in both patients with severe AoS and severe MR was improved, showing a significant increase in ET (Table 2 and 3, respectively). Overall, patients with MR showed greater improvement in ET than AoS patients (101% vs. 66% increase from baseline).
ET individual changes for patients reassessed prior to surgery are shown in Figure 1. 90% of MR patients showed a positive response to exercise (established as > 30% ET increase), while in AoS group, 62% showed the mentioned increase.
Patients with severe MR involved in prehabilitation also showed significant improvement in other functional parameters such as 6MWT, hand grip, or STS-test (Table 3).
Regarding patients allocated to control group, those with severe AoS remained functionally unchanged during surgery waiting-list time, whereas not prehabilitated patients with severe MR, showed a trend to functional decline during this time (ET 21% decrease from baseline) (Figure 1).
No patients had any adverse events or complications attributable to the physical training, neither during the sessions nor during the program period.
Table2. Functional capacity related outcomes in both AoS prehabilitation and control groups
|
Prehabilitation group
|
Control group
|
|
Baseline
|
PreSurgey
|
P-value
|
Baseline
|
PreSurgey
|
P-value
|
ET (sec)
|
331±116
|
552±254
|
0.003
|
343±206
|
441±257
|
0.084
|
6MWT (m)
|
488±81
|
507±74
|
0.072
|
465±133
|
483±133
|
0.009
|
STS (repetitions)
|
12.8±3.7
|
14.3±4.0
|
0.133
|
12.4±5.8
|
12.5±6.2
|
0.821
|
HG-D (kg)
|
30.2±8.9
|
31.2 ±8,8
|
0.251
|
31.8±8.4
|
28.5±8.5
|
0.012
|
YPAS (score)
|
45±22
|
53±16
|
0.191
|
37±16
|
42±18
|
0.297
|
Data are presented as mean ± SD. Missing values for Prehab group: ET=3, 6MWT=4, STS=4, HG-D=3, YPAS=3. Missing values for the Standard Care group: ET=9, 6MWT=8, STS=9, HG-D=7, YPAS=7.
Abbreviations: ET: endurance time; HG-D: dominant hand-grip; STS: sit-to-stand test;
YPAS: Yale physical activity survey; 6MWT: 6-minute walk test.
Table3. Functional capacity related outcomes in both MR prehabilitation and control groups
|
Prehabilitation group
|
Control group
|
|
Baseline
|
PreSurgery
|
P-value
|
Baseline
|
PreSurgery
|
P-value
|
ET (sec)
|
272±120
|
560±289
|
0.001
|
264±111
|
247±106
|
0.644
|
6MWT (m)
|
477±79
|
507±79
|
0.016
|
477±141
|
449±193
|
0.303
|
STS (repetitions)
|
11.7±3.3
|
13.3±4.4
|
0.027
|
13.3±6.3
|
14±9.4
|
0.578
|
HG-D (kg)
|
28.9±10.3
|
30.8±10
|
0.199
|
30.2±10
|
31.1±8.4
|
0.422
|
YPAS (score)
|
34±12.3
|
51.8±16.4
|
0.008
|
39.4±19.5
|
43.8±30.1
|
0.544
|
Data are presented as mean ± SD. Missing values for Prehab group: ET=1, 6MWT=1, STS=2, HG-D=1, YPAS=2. Missing values for the Standard Care group: ET=3, 6MWT=4, STS=4, HG-D=4, YPAS=4.
Abbreviations: ET: endurance time; HG-D: dominant hand-grip; STS: sit-to-stand test;
YPAS: Yale physical activity survey; 6MWT: 6-minute walk test.