TY - JOUR
T1 - Effect of β-adrenergic blockade on myocardial function and energetics in congestive heart failure
T2 - Improvements in hemodynamic, contractile, and diastolic performance with bucindolol
AU - Eichhorn, Eric J.
AU - Bedotto, John B.
AU - Malloy, Craig R.
AU - Hatfield, Barbara A.
AU - Deitchman, David
AU - Brown, Marilyn
AU - Willard, John E.
AU - Grayburn, Paul A.
PY - 1990/8
Y1 - 1990/8
N2 - The hemodynamic effects of β-adrenergic blockade with bucindolol, a nonselective β-antagonist with mild vasodilatory properties, were studied in patients with congestive heart failure. Fifteen patients (New York Heart Association class I-IV) underwent cardiac catheterization before and after 3 months of oral therapy with bucindolol. The left ventricular ejection fraction increased from 0.23±0.12 to 0.29±0.14 (p=0.007), and end-systolic elastance, a relatively load-independent determinant of contractility, increased from 0.60±0.40 to 1.11±0.45 mm Hg/ml (p=0.0049). Both left ventricular stroke work index (34±13 to 47±19 g-m/m2, p=0.0059) and minute work (5.5±2.2 to 7.0±2.6 kg-m/min, p=0.0096) increased despite reductions in left ventricular end-diastolic pressure (19±8 to 15±5 mm Hg, p=0.021). There was an upward shift in the peak +dP/dtmax-end-diastolic volume relation (p=0.0005). These data demonstrate improvements in myocardial contractility after β-adrenergic blockade with bucindolol. At a matched paced heart rate of 98±15 min-1, the time constant of left ventricular isovolumic relaxation was significantly reduced by bucindolol therapy (92±17 versus 73±11 msec, p=0.0013), and the relation of the time constant to end-systolic pressure was shifted downward (p=0.014) with therapy. The slope of the logarithm left ventricular end-diastolic pressure-end-diastolic volume relation was unchanged (p=0.51) after bucindolol. These data suggest that chronic β-adrenergic blockade with bucindolol improves diastolic relaxation but does not alter myocardial chamber stiffness. Myocardial oxygen extraction, consumption, and efficiency were unchanged despite improvement in contractile function and mechanical work. Thus, in patients with congestive heart failure, chronic β-adrenergic blockade with bucindolol significantly improves myocardial contractility and minute work, yet it does not do so at the expense of myocardial oxygen consumption. Additionally, bucindolol improves myocardial relaxation but does not affect chamber stiffness.
AB - The hemodynamic effects of β-adrenergic blockade with bucindolol, a nonselective β-antagonist with mild vasodilatory properties, were studied in patients with congestive heart failure. Fifteen patients (New York Heart Association class I-IV) underwent cardiac catheterization before and after 3 months of oral therapy with bucindolol. The left ventricular ejection fraction increased from 0.23±0.12 to 0.29±0.14 (p=0.007), and end-systolic elastance, a relatively load-independent determinant of contractility, increased from 0.60±0.40 to 1.11±0.45 mm Hg/ml (p=0.0049). Both left ventricular stroke work index (34±13 to 47±19 g-m/m2, p=0.0059) and minute work (5.5±2.2 to 7.0±2.6 kg-m/min, p=0.0096) increased despite reductions in left ventricular end-diastolic pressure (19±8 to 15±5 mm Hg, p=0.021). There was an upward shift in the peak +dP/dtmax-end-diastolic volume relation (p=0.0005). These data demonstrate improvements in myocardial contractility after β-adrenergic blockade with bucindolol. At a matched paced heart rate of 98±15 min-1, the time constant of left ventricular isovolumic relaxation was significantly reduced by bucindolol therapy (92±17 versus 73±11 msec, p=0.0013), and the relation of the time constant to end-systolic pressure was shifted downward (p=0.014) with therapy. The slope of the logarithm left ventricular end-diastolic pressure-end-diastolic volume relation was unchanged (p=0.51) after bucindolol. These data suggest that chronic β-adrenergic blockade with bucindolol improves diastolic relaxation but does not alter myocardial chamber stiffness. Myocardial oxygen extraction, consumption, and efficiency were unchanged despite improvement in contractile function and mechanical work. Thus, in patients with congestive heart failure, chronic β-adrenergic blockade with bucindolol significantly improves myocardial contractility and minute work, yet it does not do so at the expense of myocardial oxygen consumption. Additionally, bucindolol improves myocardial relaxation but does not affect chamber stiffness.
KW - Bucindolol
KW - Congestive heart failure
KW - Hemodynamics
KW - Systolic elastance
KW - β-adrenergic blockade
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U2 - 10.1161/01.CIR.82.2.473
DO - 10.1161/01.CIR.82.2.473
M3 - Article
C2 - 1973638
AN - SCOPUS:0025071544
SN - 0009-7322
VL - 82
SP - 473
EP - 483
JO - Circulation
JF - Circulation
IS - 2
ER -