The effect of a hyperbaric oxygenation course (10-14 exposures, one exposure daily at 0.7-1.0 ATA) upon the circulation function was studied in 61 patients with rheumatic mitral valve disease combined with systemic circulation insufficiency. The obtained results (reduction of the heart volume, acceleration of the blood stream within the heart and the body, increase of the stroke index, of the blood flow in the muscles of the extremities, reduction of the arterial and central venous pressure) demonstrate that the contractility of the myocardium and redistribution of the cardiac output between separate vascular regions is improved under the effect of hyperbaric oxygenation. The authors suggest that the increase of contractility in the right or left heart predominantly depends on the prevalence of mitral stenosis or circulatory insufficiency.

Efuni, Rabkin, Rodionov, Bukaev, Svirshchevskiĭ, , , , (1977). [Effect of hyperbaric oxygenation on the circulatory function in rheumatic mitral valve disease]. Kardiologiia, 1977 Mar;17(3):29-36. https://www.ncbi.nlm.nih.gov/pubmed/886698