Respiratory muscle trainings as a way of physical rehabilitation for old patients with complicated myocardial infarction

Background: Physical exercises are well known to be an important part of comprehensive cardiac rehabilitation (CR), but many protocols of physical exercises are not applicable for the old patients for many reasons. Purpose: To study the possibility of respiratory muscles trainings (RMT) in old patients with myocardial infarction (MI) and heart failure (HF) as a way of physical rehabilitation. Methods: 63 patients 84,3±5,2 years old with MI and NYHA II- III HF were randomized to either an exercise training group (EG) (32pts) or to a control group (CG). The CG patients had standard CR according to the national guidelines. The EG participated additionally in a RMT with gradual increase of inspire and expire resistance. At hospital stage, 10 to 12 trainings were held for 20 minutes twice a day with following trainings at home by themselves for 12 months. Peak oxygen consumption (VO2peak) during 6 minute walking test (6 MWT), maximal inspiratory mouth pressures (PI max) and heath related quality of life by SF-36 were measured at baseline and in 12 months. Results: After 12 weeks there was significant increase in results of 6 MWT in EG (167,6±9,37 m in EG vs 168,2±9,12 m in CG at baseline, p>0,05; after 12 months 185±8,76m vs 179,3±8,85 m p<0,01), VO2peak in EG (5,96±1,84ml/kg/min in EG vs 5,99±1,91 ml/kg/min in CG at baseline, p>0,05; after 12 months 8,18±1,46 ml/kg/min vs 6,35±1,11 ml/kg/min, p<0,01) and PImax in EG (median PI max, 6,2 in both groups [25th-75th percentile range 6,4-6.8 in EG vs 25th-75th percentile range 6,2-6,8 in CG] at baseline, p=0,7), after 12 months EG median PI max, 6,9 in EG [25th-75th percentile range6,8-7,1] vs median PI max, 6,6 [25th-75th percentile range 6,3-6,3] in CG, p<0,01). Health-related quality of life increased in both groups, but in EG patients' results in physical functioning, bodily pain, vitality, role emotional scales were significantly higher. EG patients had significantly less hospitalizations because of HF progression (10,9% in EG vs 17,5% in CG) and pneumonias (14,1% vs 19.3%). There were 4 lethal outcomes in EG vs 7 in CG. Conclusion: RMT in old patients with MI and HF improves physical capacity, maximal inspiratory mouth pressures, health-related quality of life and decrease the number of hospitalizations because of HF progression and pneumonias during the first year after MI