Respiratory muscle endurance is limited by lower ventilatory efficiency in post-myocardial infarction patients

Laura M T Neves, Marlus Karsten, Victor R Neves, Thomas Beltrame, Audrey Borghi-Silva, Aparecida M Catai, Laura M T Neves, Marlus Karsten, Victor R Neves, Thomas Beltrame, Audrey Borghi-Silva, Aparecida M Catai

Abstract

Background: Reduced respiratory muscle endurance (RME) contributes to increased dyspnea upon exertion in patients with cardiovascular disease.

Objective: The objective was to characterize ventilatory and metabolic responses during RME tests in post-myocardial infarction patients without respiratory muscle weakness.

Method: Twenty-nine subjects were allocated into three groups: recent myocardial infarction group (RG, n=9), less-recent myocardial infarction group (LRG, n=10), and control group (CG, n=10). They underwent two RME tests (incremental and constant pressure) with ventilatory and metabolic analyses. One-way ANOVA and repeated measures one-way ANOVA, both with Tukey post-hoc, were used between groups and within subjects, respectively.

Results: Patients from the RG and LRG presented lower metabolic equivalent and ventilatory efficiency than the CG on the second (50± 06, 50± 5 vs. 42± 4) and third part (50± 11, 51± 10 vs. 43± 3) of the constant pressure RME test and lower metabolic equivalent during the incremental pressure RME test. Additionally, at the peak of the incremental RME test, RG patients had lower oxygen uptake than the CG.

Conclusions: Post-myocardial infarction patients present lower ventilatory efficiency during respiratory muscle endurance tests, which appears to explain their inferior performance in these tests even in the presence of lower pressure overload and lower metabolic equivalent.

Figures

Figure 1
Figure 1
Diagram of sample distribution for the recent post-myocardial infarction group (RG), the less-recent post-myocardial infarction group (LRG), and the control group (CG).
Figure 2
Figure 2
Illustration of the percentage of oxygen uptake at peak exercise (%VO2peak) during the incremental and constant pressure protocol endurance tests for the recent infarction group (RG-white), the less-recent infarction group (LRG-black), and the control group (CG-gray).

References

    1. Morrison NJ, Fairbarn MS, Pardy RL. The effect of breathing frequency on inspiratory muscle endurance during incremental threshold loading. Chest. 1989;96:85–88.
    1. Jones NL, Killian KJ. Mechanisms of disease: Exercise limitation in health and disease. N Engl J Med. 2000;342(9):632–641.
    1. Caroci AS, Lareau SC, Linda L. Descriptors of dyspnea by patients with chronic obstructive pulmonary disease versus congestive heart failure. Heart Lung. 2004;33:102–110.
    1. Hamilton AL, Killian KJ, Summers E, Jones NL. Muscle strength, symptom intensity, and exercise capacity in patients with cardiorespiratory disorders. Crit Care Med. 1995;152:2021–2031.
    1. Stendardi L, Grazzini M, Gigliotti F, Lotti P, Scano G. Dyspnea and leg effort during exercise. Respir Med. 2005;99:933–942.
    1. Ambrosino N, Serradori M. Determining the cause of dyspnoea: linguistic and biological descriptors. Chron Respir Dis. 2006;3:117–122.
    1. Reid WD, Clarke TJ, Wallace AM. Respiratory muscle injury: evidence to date and potential mechamisms. Can J Apl Physiol. 2001;26:356–387.
    1. Wastford ML, Murphy A J, Pine MJ. The effects of age in on respiratory muscle function and performance in older adults. J Sci Med Sport. 2007;10:36–44.
    1. Ribeiro JP, Chiappa GR, Callegaro CC. The contribution of inspiratory muscles function to exercise limitation in heart failure: pathophysiological mechanisms. Rev Bras Fisioter. 2012;16(4):261–267.
    1. Hautmann H, Hefele S, Schotlen K, Huber RM. Maximal inspiratory mouth pressures (PIMAX) in healthy subjects - what is lower limit of normal? Respir Med. 2000;94:689–693.
    1. Dall'Ago P, Chiappa GR, Guths H, Stein R, Ribeiro JP. Inspiratory muscle training in patients with heart failure and inspiratory muscle weakness: a randomized trial. J Am Coll Cardiol. 2006 Feb 21;47(4):757–763.
    1. Wasserman K, Hansen JE, Sue DY, Whipp BJ, Casaburi R. Principles of exercise testing and interpretation. Philadelphia: Lea & Febiger; 1999.
    1. Windisch W, Hennings E, Sorichter S, Hamm H, Criée CP. Peak or plateau maximal inspiratory mouth pressure: which is best? Eur Respir J. 2004;23:708–713.
    1. Neves LMT, Karsten M, Neves VR, Beltrame T, Borghi-Silva A, Catai AM. Relationship between inspiratory muscle capacity and peak exercise tolerance in post-myocardial infarction patients. Heart Lung. 2012;41(2):137–145.
    1. Neves LMT, Karsten M, Borghi-Silva A, Catai AM. Comportamento ventilatório e metabólico na avaliação da endurance dos músculos inspiratórios de indivíduos pós-infarto do miocárdio. Rev Bras Fisioter. 2010;14(Supl.1):449–449.
    1. Pereira CAC. Espirometria. Diretrizes para testes de função pulmonar. J Bras Pneumol. 2002;28(3):S1–82.
    1. Balady GJ, Arena R, Sietsema K, Myers J, Coke L, Fletcher GF, et al. Clinician's Guide to cardiopulmonary exercise testing in adults: a scientific statement from the American Heart Association. Circulation. 2010;122:191–225.
    1. Higa MN, Silva E, Neves VFC, Catai AM, Gallo L, Jr, Sá MFS. Comparison of anaerobic threshold determined by visual and mathematical methods in healthy women. Braz J Med Biol Res. 2007;40:501–508.
    1. American Thoracic Society/European Respiratory Society ATS/ERS Statement on respiratory muscle testing. Am J Resp Crit Care Med. 2002;166:518–624.
    1. Neder JA, Andreoni S, Lerario MC, Nery LE. Reference values for lung function tests. II. Maximal respiratory pressures and voluntary ventilation. Braz J Med Biol Res. 1999;32:719–727.
    1. Gassner LA, Dunn S, Piller N. Aerobic exercise and the post myocardial infarction patient: A review of the literature. Heart Lung. 2003;32:258–265.
    1. Jones GL, Killian KJ, Summers E, Jones NJ. Inspiratory muscle forces and endurance in maximum resistive loading. J Appl Physiol. 1985;58:1608–1615.
    1. Ainsworth BE, Haskell WL, Leon AS, Jacobs DR, Montoye JH, Sallis JF, et al. Compendium of physical activities: classification of energy costs of human physical activities. Med Sci Sports Exerc. 1993;25(1):71–80.
    1. Chiappa GR, Roseguini BT, Vieira PJC, Alves CN, Tavares A, Winkelmann ER, et al. Inspiratory muscle training improves blood flow to resting and exercising limbs in patients with chronic heart failure. J Am Coll Cardiol. 2008;51(17):1663–1671.
    1. Martyn JB, Moreno RH, Paré PD, Pardy RL. Measurement of inspiratory muscle performance with threshold loading. Am Rev Respir Dis. 1987;135:919–923.
    1. Eastwood PR, Hillman DR, Finucane KF. Inspiratory muscles performance in endurance athletes and sedentary subjects. Respirology. 2001;6:95–104.
    1. Freedman S, Campbell EJM. The ability of normal subjects to tolerate added inspiratory loads. Respir Physiol. 1970;10:213–235.
    1. Jederlinic P, Muspratt JA, Miller MJ. Inspiratory muscle training in clinical practice: physiologic conditioning or habituation to suffocation? Chest. 1984;86:870–873.
    1. McElvaney G, Fairban MS, Wilcox PG, Pardy RL. Comparison of two-minute incremental threshold loading and maximal loading as measures of respiratory muscles endurance. Chest. 1989;96:557–563.
    1. Yan S, Sliwinski P, Gauthier AP, Lichros I, Zakynthinos S, Macklem PT. Effect of global inspiratory muscle fatigue on ventilatory and respiratory muscle responses to CO2. J Appl Physiol. 1993;75(3):1371–1377.
    1. Clanton TL, Diaz PT. Clinical assessment of the respiratory muscles. Phys Ther. 1995;75(11):983–995.
    1. Callegaro CC, Martinez D, Ribeiro PAB, Brod M, Ribeiro JP. Augmented peripheral chemoreflex in patients with heart failure and inspiratory muscle weakness. Respir Physiol Neurobiol. 2010;171:31–35.

Source: PubMed

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