Effect of exercise training on left ventricular remodeling in patients with myocardial infarction and possible mechanisms

Table 1 Follow-up and examination schedule

Item	Immediately	Days 10-14	Follow-up (mo)
			1	6
Informed consent	√
Medical history	√
Physical examination	√		√	√
MMP-9	√	√	√	√
TIMP-1	√	√	√	√
Transthoracic echocardiography		√		√
CPET		√		√
Concomitant medication	√	√	√	√

MMP-9: Matrix metalloproteinase-9; TIMP-1: Tissue inhibitor of metalloproteinases-1; CPET: Cardiopulmonary exercise testing.

Table 2 Patient characteristics at randomization to intervention and control groups, n (%)

	Rehabilitation exercise group	Control group
	n = 30	n = 30
Age (yr)	55 ± 9	58 ± 8
Infarction area, n (%)
Anterior AMI	18 (60)	15 (50)
Non-anterior AMI	12 (40)	15 (50)
History of smoking, n (%)	28 (93.3)	24 (80)
Concomitant disease, n (%)
Diabetic mellitus	2 (6.7)	3 (10)
Hypertension	5 (16.6)	4 (13.3)
Hypercholesteremia	3 (10)	4 (13.3)
Drug therapy, n (%)
Aspirin	30 (100)	30 (100)
Clopidogrel	29 (96.7)	28 (93.3)
β-receptor blocker	25 (83.3)	28 (93.3)
ACEI/ARB	29 (96.7)	27 (90)
Statins	28 (93.3)	29 (96.7)

AMI: Acute myocardial infraction; ACEI: Angiotensin-converting enzyme inhibitor; ARB: Angiotensin receptor blocker.

Table 3 Cardiopulmonary exercise testing in rehabilitation exercise and control groups

	Baseline		6 mo after onset of myocardial infarction
	Control group (n = 30)	Exercise group (n = 30)	Control group (n = 30)	Exercise group (n = 30)
Exercise time (min)	8.19 ± 2.55	8.11 ± 2.69	9.37 ± 2.48a	11.89 ± 2.34b
Anaerobic threshold (mL/min)	958.64 ± 298.65	977.23 ± 288.33	1235.88 ± 347.56b	1388.07 ± 355.67b
Metabolic equivalent at anaerobic threshold	3.76 ± 1.05	3.89 ± 1.01	4.58 ± 1.06b	5.20 ± 1.19b
Peak oxygen uptake (mL/min)	1272.37 ± 346.85	1267.35 ± 322.84	1507.88 ± 398.46b	1664.67 ± 365.35b
Peak metabolic equivalent	4.98 ± 1.03	4.87 ± 0.98	5.62 ± 1.01b	6.38 ± 1.09b

Comparison of the second cardiopulmonary exercise testing (CPET) and the first CPET of the same group.

^aP < 0.05.

^bP < 0.01. CPET: Cardiopulmonary exercise testing.

Table 4 Differences of results of the two cardiopulmonary exercise tests of patients in the two groups

	Changes of the two tests
	Control group (n = 30)	Exercise group (n = 30)
Exercise time (min)	1.13 ± 1.69	3.41 ± 2.88b
Anaerobic threshold (mL/min)	252.13 ± 233.66	405.36 ± 207.89a
Metabolic equivalent at anaerobic threshold	0.82 ± 0.71	1.46 ± 0.82b
Peak oxygen uptake (mL/min)	232.73 ± 254.96	402.88 ± 258.35a
Peak metabolic equivalent	0.77 ± 0.86	1.49 ± 0.93b

Intergroup comparison.

^aP < 0.05.

^bP < 0.01. CPET: Cardiopulmonary exercise testing.

Table 5 Echocardiography results in rehabilitation exercise and control groups

	Baseline value		6 mo
	Control group (n = 30)	Rehabilitation exercise group (n = 30)	Control group (n = 30)	Rehabilitation exercise group (n = 30)
LVEF	56.1% ± 7.98%	57.73% ± 7.89%	53% ± 8.86%	58.4% ± 8.6%a
LVRM positive results			52.60%	26.6%a

Intergroup comparison.

^aP < 0.01. LVEF: Left ventricular ejection fraction; LVRM: Left ventricular remodeling.

Table 6 Comparison of matrix metalloproteinase-9, tissue inhibitor of metalloproteinases-1, and matrix metalloproteinase-9/tissue inhibitor of metalloproteinases-1 ratio in rehabilitation exercise and control groups at different time points

Items	Time	Rehabilitation exercise group (n = 30)	Control group (n = 30)
MMP-9 (ng/mL)	Immediately	6.7 ± 2.97	6.8 ± 3.12
	Days 10-14	8.2 ± 2.5	8.1 ± 2.55
	Day 30	4.2 ± 1.88	5.0 ± 1.98a
	6 mo	4.0 ± 1.87	5.1 ± 2.02a
TIMP-1 (ng/mL)	Immediately	2.1 ± 0.52	2.1 ± 0.51
	Days 10-14	2.4 ± 0.71	2.5 ± 0.65
	Day 30	2.8 ± 0.67	3.0 ± 0.55a
	6 mo	2.7 ± 0.56	2.98 ± 0.51a
MMP-9/TIMP-1	Immediately	3.05 ± 1.05	2.98 ± 1.03
	Days 10-14	4.21 ± 1.58	4.11 ± 1.44
	Day 30	1.78 ± 0.88	1.25 ± 0.66a
	6 mo	1.58 ± 0.67	1.22 ± 0.58a

Intergroup comparison.

^aP < 0.05. MMP-9: Matrix metalloproteinase-9; TIMP-1: Tissue inhibitor of metalloproteinases-1.