Abstract
Background:It has been previously shown that the inspiratory muscles of patients with congestive heart failure (CHF) are weaker than those of normal persons. This weakness may contribute to the dyspnea and limit exercise capacity in these patients. The respiratory muscles can be trained for both strength and endurance.
Hypothesis:The present study was designed to evaluate the effect of specific inspiratory muscle training (SIMT) on inspiratory muscle performance, lung function, dyspnea, and exercise capacity in patients with moderate heart failure.
Methods:Twenty patients with CHF (NYHA functional class II‐III) were recruited for the study. The subjects were randomized into two groups: 10 patients were included in the study group and received SIMT and 10 patients were assigned to the control group and received sham training. Subjects in both groups trained daily, 6 times/week, for one‐half h, for 3 months. The subjects started breathing at a resistance equal to 15% of their PImax for 1 week and the resistance was then increased incrementally to 60%. Spirometry, inspiratory muscle strength (assessed by measuring the PImax at residual volume), and endurance (expressed by the relationship between PmPeak and PImax), the 12‐min walk test, and peak VO2 were performed before the beginning and at the end of the training period.
Results:All patients in the training group showed an increase in the inspiratory muscle strength [mean (± standard error of the mean) PImax increased from 46.5 ± 4.7 to 63.6 ± 4.0 cm H2O, p < 0.005], and endurance (mean PmPeak/PImax from 47.8 ± 3.6 to 67.7 ± 1.7%, p < 0.05), while they remained unchanged in the control group. This was associated in the training group with a small but significant increase in forced vital capacity, a significant increase in the distance walked (458 ± 29 to 562 ± 32 m, p < 0.01), and an improvement in the dyspnea index score. No statistically significant change in the mean peak VO2 was noted in either group.
Conclusions:Specific inspiratory muscle training resulted in increased inspiratory muscle strength and endurance. This increase was associated with decreased dyspnea, increase in submaximal exercise capacity, and no change in maximal exercise capacity. This training may prove to be a complementary therapy in patients with congestive heart failure.
Keywords: specific inspiratory muscle training, dyspnea, exercise tolerance, congestive heart failure
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References
- 1. Cokcroft A, Guz A: Breathlessness. Postgrad Med J 1987; 63: 637–641 [DOI] [PMC free article] [PubMed] [Google Scholar]
- 2. Sullivan MJ, Higginbotham MB, Cobb FR: Increased exercise ventilation in patients with chronic heart failure: Intact ventilatory control despite hemodynamic and pulmonary abnormalities. Circulation 1988; 77: 552–559 [DOI] [PubMed] [Google Scholar]
- 3. Franciosa JA, Leddy CL, Wilen M, Schwartz DE: Relation between hemodynamic and ventilatory responses in determining exercise capacity in severe congestive heart failure. Am J Cardiol 1984; 53: 127–134 [DOI] [PubMed] [Google Scholar]
- 4. Packer M: How should we judge the efficacy of drug therapy in patients with chronic congestive heart failure? The insights of six blind men. J Am Coll Cardiol 1987; 9: 433–438 [DOI] [PubMed] [Google Scholar]
- 5. Lipkin DP, Poole‐Wilson PA: Symptoms limiting exercise in chronic heart failure. Br Med J 1986; 292: 1030–1031 [DOI] [PMC free article] [PubMed] [Google Scholar]
- 6. Gibbs JSR, Keegan J, Wright C, Fox KM, Poole‐Wilson PA: Pulmonary artery pressure changes during exercise and daily activities in chronic heart failure. J Am Coll Cardiol 1990; 15: 52–61 [DOI] [PubMed] [Google Scholar]
- 7. Lipkin DP, Canepa‐Anson R, Stephens MR, Poole‐Wilson PA: Factors determining symptoms in heart failure: Comparison of fast and slow exercise tests. Br Heart J 1986; 55: 439–445 [DOI] [PMC free article] [PubMed] [Google Scholar]
- 8. Killian KG, Campbell EJM: Dyspnea and exercise. Ann Rev Physiol 1983; 445: 465–479 [DOI] [PubMed] [Google Scholar]
- 9. Killian KG, Jones NL: The use of exercise testing and other methods in the investigation of dyspnea. Clin Chest Med 1984; 5: 99–108 [PubMed] [Google Scholar]
- 10. Jones GL, Killian KJ, Summers E: The sense of effort, oxygen cost, and pattern of breathing associated with progressive elastic loading to fatigue (abstr). Fed Proc 1984; 42: 1420 [Google Scholar]
- 11. Killian KJ, Gandevia SC, Summers E: Effect of increased lung volume on perception of breathlessness, effort, and tension. J Appl Physiol 1984; 57: 686–691 [DOI] [PubMed] [Google Scholar]
- 12. McParland C, Krishnan B, Wang Y, Gallagher CG: Inspiratory muscle weakness and dyspnea in chronic heart failure. Am Rev Respir Dis 1992; 146: 467–472 [DOI] [PubMed] [Google Scholar]
- 13. Mancini DM, Henson D, LaManca J, Levine S: Respiratory muscle function and dyspnea in patients with chronic congestive heart failure. Circulation 1992; 86: 909–918 [DOI] [PubMed] [Google Scholar]
- 14. Hammond MD, Bauer KA, Sharp JT, Rocha RD: Respiratory muscle strength in congestive heart failure. Chest 1990; 98: 1091–1094 [DOI] [PubMed] [Google Scholar]
- 15. Pardy RL, Leith DE: Ventilatory muscle training. Respir Care 1984; 29: 278–284 [Google Scholar]
- 16. Shaffer TH, Wolfson MR, Bhutani VK: Respiratory muscle function, assessment, and training. Phys Ther 1981; 61: 1711–1723 [DOI] [PubMed] [Google Scholar]
- 17. Pardy RL, Leith DE: Ventilatory muscle training In The Thorax (Eds. Roussos C, Macklem PT.), p. 1353–1369. New York: Marcel Dekker Inc., 1986. [Google Scholar]
- 18. Mancini DM, Henson D, LaManca J, Donchez L, Levine S: Benefit of selective respiratory muscle training on exercise capacity in patients with chronic congestive heart failure. Circulation 1995; 91: 320–329 [DOI] [PubMed] [Google Scholar]
- 19. Black LF, Hyatt RE: Maximal respiratory pressures: Normal values and relationship to age and sex. Am Rev Respir Dis 1969; 99: 696–702 [DOI] [PubMed] [Google Scholar]
- 20. Nickerson BG, Keens TG: Measuring ventilatory muscle endurance in humans as sustainable inspiratory pressure. J Appl Physiol 1982; 52: 768–772 [DOI] [PubMed] [Google Scholar]
- 21. Martyn JB, Moreno RH, Pare PD, Pardy RL: Measurement of inspiratory muscle performance with incremental threshold loading. Am Rev Respir Dis 1987; 135: 919–923 [DOI] [PubMed] [Google Scholar]
- 22. McGavin CR, Gupta SP, McHardy GJR: Twelve‐minute walking test for assessing disability in chronic bronchitis. Br Med J 1976; 1: 822–823 [DOI] [PMC free article] [PubMed] [Google Scholar]
- 23. Mahler D, Harver A: Clinical measurement of dyspnea In Dyspnea (Ed. Mahler D.), p. 75–100. Mt Kisco, N.Y.: Futura Publishing, 1990. [Google Scholar]
- 24. Beiman M: Respiratory training and unloading In Principles and Practice of Pulmonary Rehabilitation (Eds. Casaburi R, Petty T.), p. 225–240. Philadelphia, Pa.: WB Saunders Co, 1993. [Google Scholar]
- 25. Weiner P, Azgad Y, Ganam R: Inspiratory muscle training combined with general exercise reconditioning in patient with COPD. Chest 1992; 102: 1351–1356 [DOI] [PubMed] [Google Scholar]
- 26. Altose M: Assessment and management of breathlessness. Chest 1985; 88: 77S–83S [DOI] [PubMed] [Google Scholar]
- 27. Middlekauff HR, Mark AL: The treatment of heart failure: The role of neurohumoral activation. Intern Med 1993; 37 (2): 112–122 [DOI] [PubMed] [Google Scholar]
- 28. Polak J, Holman B, Wynne J, Colucci WS: Right ventricular ejection fraction: An indicator of increased mortality in patients with congestive heart failure associates with coronary artery disease. J Am Coll Cardiol 1983; 2: 217–224 [DOI] [PubMed] [Google Scholar]
- 29. Leith D, Bradley M: Ventilatory strength and endurance training. J Appl Physiol 1976; 41: 508–516 [DOI] [PubMed] [Google Scholar]
- 30. Jugdutt B, Michorowski B, Kappagoda C: Exercise training after anterior Q wave myocardial infarction: Importance of regional left ventricular function and topography. J Am Coll Cardiol 1988; 12: 362–372 [DOI] [PubMed] [Google Scholar]
- 31. Gaudron P, Hu K, Schamberger R, Budin M Walter B, Ertl G: Effect of endurance training early or late after coronary artery occlusion on left ventricular remodeling, hemodynamics, and survival in rats with chronic transmural myocardial infarction. Circulation 1994; 89: 402–412 [DOI] [PubMed] [Google Scholar]
- 32. Sullivan M, Higginbotham M, Coob F: Exercise training in patients with severe left ventricular dysfunction: Hemodynamic and metabolic effects. Circulation 1988; 778: 506–515 [DOI] [PubMed] [Google Scholar]
- 33. Musch T, Moore R, Smaldone P, Riedy M, Zelis R: Cardiac adaptations to endurance training in rats with a chronic myocardial infarction. J Appl Physiol 1989; 66: 712–719 [DOI] [PubMed] [Google Scholar]