Wisenbaugh T, Essop R, Middlemost S, Skoularigis J, Rothlisberger C, Skudicky D, Sareli P
Cardiology Department, Baragwanath Hospital, Johannesburg, South Africa.
Am Heart J. 1993 Mar;125(3):786-90. doi: 10.1016/0002-8703(93)90172-6.
Intravenous atenolol was given to 31 patients just before balloon mitral valvotomy to assess the hemodynamic efficacy and safety of beta-blockade in mitral stenosis complicated by pulmonary hypertension. Hemodynamic response in patients with pulmonary resistance > 600 dynes.sec.cm-5 (group 2, n = 17) was compared with those (group 1, n = 14) with a resistance below this value. In addition to a higher pulmonary arterial resistance (by design), patients in group 2 had a higher systemic resistance, lower cardiac index, and smaller mitral valve area compared with those in group 1. After atenolol infusion, transmitral gradient and left atrial pressure improved similarly. In spite of the decline in left atrial pressure, pulmonary vascular resistance increased in both groups, more in group 2 (847 +/- 398 dynes.sec.cm-5 to 135 +/- 648 dynes.sec.cm-5) than in group 1 (291 +/- 149 dynes.sec.cm-5 to 363 +/- 200; p < 0.001 for drug effect and p = 0.027 for group effect by two-way analysis of variance). Cardiac index declined similarly from 2.77 +/- 0.51 L/min/m2 to 2.37 +/- 0.37 L/min/m2 in group 1 and from 2.33 +/- 0.58 L/min/m2 to 1.92 +/- 0.54 L/min/m2 in group 2. Systemic pressure tended to decline only in group 2 (mean aortic pressure, 89 +/- 12 mm Hg to 89 +/- 12 mm Hg in group 1 and 90 +/- 9 mm Hg to 83 +/- 12 mm Hg in group 2; p = 0.06 for group effect).(ABSTRACT TRUNCATED AT 250 WORDS)