Effects of balloon mitral valvuloplasty on left ventricular muscle function.
Echocardiographically determined ventricular load and performance were compared in 40 consecutive patients with severe mitral stenosis before and 24 h after successful and uncomplicated balloon mitral valvuloplasty in order to clarify the role of loading conditions in causation of reduced left ventricular ejection fraction. After valvuloplasty, mitral valve area increased 2-fold. A modest increase in ejection fraction (53 +/- 11% to 57 +/- 8%, P = 0.021) occurred with an insignificant increase in end-diastolic volume (44 +/- 10 to 48 +/- 16 ml/m2, P = 0.063) and no change in wall stress (61 +/- 19 to 59 +/- 19 kdynes/cm3, P = 0.85) (10(5) dynes = 1 N). There was no correlation between changes in fractional shortening and wall stress (r = 0.07) and between changes in end-diastolic volume and fractional shortening (r = 0.12). Contractile performance estimated by a performance-afterload relation was unchanged after the valvuloplasty. Factors other than a change in loading conditions might be responsible for a modest improvement in ejection performance following mitral valvuloplasty.
Mohan
J C
JC
Dept of Cardiology, G. B. Pant Hospital, New Delhi, India.
Bhargava
M
M
Agrawal
R
R
Arora
R
R
D000293:Adolescent; D000328:Adult; D000704:Analysis of Variance; D006328:Cardiac Catheterization; D002404:Catheterization; D002648:Child; D004452:Echocardiography; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D008946:Mitral Valve Stenosis / Q000628:therapy*; D013318:Stroke Volume / Q000502:physiology; D016896:Treatment Outcome; D016277:Ventricular Function, Left / Q000502:physiology*