Tags

Type your tag names separated by a space and hit enter

Exercise-induced hyperkalemia and concentration of Na,K-pumps in skeletal muscle in mitral stenosis: effect of balloon mitral valvotomy.
J Heart Valve Dis. 1999 Jul; 8(4):430-9.JH

Abstract

BACKGROUND AND AIMS OF THE STUDY

The study aim was to examine the effects of balloon mitral valvotomy (BMV) on exercise-induced hyperkalemia, and on changes in the concentration of Na,K-pumps in skeletal muscle, as an exaggerated exercise-induced rise in potassium concentration ([K+]) may contribute to exertional fatigue and breathlessness.

METHODS

Eight subjects were evaluated with mitral stenosis (mean age 34 +/- 5.2 years) before, and at two weeks and four months after BMV. Subjects underwent incremental exercise to exhaustion for exercise-induced rise in [K+] and vastus lateralis biopsy for concentration of Na,K-pumps.

RESULTS

Mean (+/- SE) valve area increased from 0.89 +/- 0.03 cm2 before to 1.75 +/- 0.05 cm2 after BMV. There was a progressive increase in VO2,max (15.3 +/- 1.6, 17.2 +/- 1.4 and 19.9 +/- 1.9 l/kg/min) at baseline, early after and later after BMV, respectively (p < 0.01). The rise in [K+] with absolute workload fell progressively at early and late follow up post-BMV (p < 0.05), but was unchanged when plotted against percentage of VO2,max to match for relative workload. The concentration of Na,K-pumps was similar to baseline at early follow up (233 +/- 10 versus 228 +/- 15 pmol/g wet weight), but was significantly increased at late follow up after four months (265 +/- 17 pmol/g; p < 0.05). When the relationship between the concentration of Na,K-pumps and the exercise-induced rise in [K+] was studied, a negative correlation was found. However, correlation analysis for the effects of changes in Na,K-pumps on changes in exercise hyperkalemia after BMV was not significant.

CONCLUSIONS

The progressive reduction in exercise-induced rise in [K+] after BMV may contribute to the progressive improvement in exercise performance. The increased concentration of Na,K-pumps in skeletal muscle may assist in this improvement, and emphasizes the importance of peripheral adaptations in clinical improvement after BMV.

Authors+Show Affiliations

Barlow CW
University Laboratory of Physiology, University of Oxford, UK.
Long JE
No affiliation info available
Manga P
No affiliation info available
Meyer TE
No affiliation info available
Paterson DJ
No affiliation info available
Robbins PA
No affiliation info available

MeSH

AdultCatheterizationExerciseExercise ToleranceFemaleHumansHyperkalemiaMaleMitral Valve StenosisMuscle, SkeletalSodium-Potassium-Exchanging ATPase

Pub Type(s)

Journal Article
Research Support, Non-U.S. Gov't

Language

eng

PubMed ID

10461244

Citation

Barlow, C W., et al. "Exercise-induced Hyperkalemia and Concentration of Na,K-pumps in Skeletal Muscle in Mitral Stenosis: Effect of Balloon Mitral Valvotomy." The Journal of Heart Valve Disease, vol. 8, no. 4, 1999, pp. 430-9.
Barlow CW, Long JE, Manga P, et al. Exercise-induced hyperkalemia and concentration of Na,K-pumps in skeletal muscle in mitral stenosis: effect of balloon mitral valvotomy. J Heart Valve Dis. 1999;8(4):430-9.
Barlow, C. W., Long, J. E., Manga, P., Meyer, T. E., Paterson, D. J., & Robbins, P. A. (1999). Exercise-induced hyperkalemia and concentration of Na,K-pumps in skeletal muscle in mitral stenosis: effect of balloon mitral valvotomy. The Journal of Heart Valve Disease, 8(4), 430-9.
Barlow CW, et al. Exercise-induced Hyperkalemia and Concentration of Na,K-pumps in Skeletal Muscle in Mitral Stenosis: Effect of Balloon Mitral Valvotomy. J Heart Valve Dis. 1999;8(4):430-9. PubMed PMID: 10461244.
* Article titles in AMA citation format should be in sentence-case
TY - JOUR T1 - Exercise-induced hyperkalemia and concentration of Na,K-pumps in skeletal muscle in mitral stenosis: effect of balloon mitral valvotomy. AU - Barlow,C W, AU - Long,J E, AU - Manga,P, AU - Meyer,T E, AU - Paterson,D J, AU - Robbins,P A, PY - 1999/8/26/pubmed PY - 1999/8/26/medline PY - 1999/8/26/entrez SP - 430 EP - 9 JF - The Journal of heart valve disease JO - J Heart Valve Dis VL - 8 IS - 4 N2 - BACKGROUND AND AIMS OF THE STUDY: The study aim was to examine the effects of balloon mitral valvotomy (BMV) on exercise-induced hyperkalemia, and on changes in the concentration of Na,K-pumps in skeletal muscle, as an exaggerated exercise-induced rise in potassium concentration ([K+]) may contribute to exertional fatigue and breathlessness. METHODS: Eight subjects were evaluated with mitral stenosis (mean age 34 +/- 5.2 years) before, and at two weeks and four months after BMV. Subjects underwent incremental exercise to exhaustion for exercise-induced rise in [K+] and vastus lateralis biopsy for concentration of Na,K-pumps. RESULTS: Mean (+/- SE) valve area increased from 0.89 +/- 0.03 cm2 before to 1.75 +/- 0.05 cm2 after BMV. There was a progressive increase in VO2,max (15.3 +/- 1.6, 17.2 +/- 1.4 and 19.9 +/- 1.9 l/kg/min) at baseline, early after and later after BMV, respectively (p < 0.01). The rise in [K+] with absolute workload fell progressively at early and late follow up post-BMV (p < 0.05), but was unchanged when plotted against percentage of VO2,max to match for relative workload. The concentration of Na,K-pumps was similar to baseline at early follow up (233 +/- 10 versus 228 +/- 15 pmol/g wet weight), but was significantly increased at late follow up after four months (265 +/- 17 pmol/g; p < 0.05). When the relationship between the concentration of Na,K-pumps and the exercise-induced rise in [K+] was studied, a negative correlation was found. However, correlation analysis for the effects of changes in Na,K-pumps on changes in exercise hyperkalemia after BMV was not significant. CONCLUSIONS: The progressive reduction in exercise-induced rise in [K+] after BMV may contribute to the progressive improvement in exercise performance. The increased concentration of Na,K-pumps in skeletal muscle may assist in this improvement, and emphasizes the importance of peripheral adaptations in clinical improvement after BMV. SN - 0966-8519 UR - https://www.unboundmedicine.com/medline/citation/10461244/Exercise_induced_hyperkalemia_and_concentration_of_NaK_pumps_in_skeletal_muscle_in_mitral_stenosis:_effect_of_balloon_mitral_valvotomy_ L2 - https://medlineplus.gov/exerciseandphysicalfitness.html DB - PRIME DP - Unbound Medicine ER -