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Afterload reduction by hydralazine in children with a ventricular septal defect as determined by aortic input impedance

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Hydralazine was administered at cardiac catheterization to eight children with a ventricular septal defect (age: 2.2–8.8 years), and the extent of afterload reduction was determined using aortic input impedance and wall stress. The pulmonary to systemic blood flow ratio decreased from 2.2±0.8 to 1.8±0.4 (p<0.05) and the pulmonary systemic resistance ratio increased from 0.11±0.08 to 0.13±0.10 (p<0.05) after hydralazine administration. Hydralazine reduced mean aortic pressure and the amplitude of the late systolic peak of the aortic pressure wave. Peak flow velocity in the descending aorta increased from 62±14 to 81±24 cm/sec (p<0.05). Peripheral resistance decreased significantly from 13.3±5.9 to 6.6±3.7 103 dyn sec/cm3 (p<0.05). The modulus of the first harmonic, indicating pulse wave reflection, decreased from 1196±575 to 815±382 dyn sec/cm3 (p<0.05). The characteristic impedance, indicating aortic stiffness, did not change. End-systolic wall stress decreased significantly from 54.4±16.7 to 34.8±10.2 g/cm2 (p<0.01). Hydralazine acutely achieved afterload reduction by reducing both peripheral resistance and pulse wave reflection, and increased stroke volume.

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  1. 1.

    Beekman RH, Rocchini AP, Rosenthal A, et al. Hemodynamic effects of hydralazine in infants with a large ventricular septal defect.Circulation 1982;65:523–528.

  2. 2.

    Nakazawa M, Takao A, Chon Y, et al. Significance of systemic vascular resistance in determining the hemodynamic effects of hydralazine on large ventricular septal defects.Circulation 1983;68:420–424.

  3. 3.

    Montigny M, Davignon A, Fouron JC, et al. Captopril in infants for congestive heart failure secondary to a large ventricular left-to-right shunt.Am J Cardiol 1989;63:631–633.

  4. 4.

    Shaddy RE, Teitel DF, Brett C. Short-term hemodynamic effects of captopril in infants with congestive heart failure.Am J Dis Child 1988;142:100–105.

  5. 5.

    Rheuban KS, Carpenter MA, Ayers CA, et al. Acute hemodynamic effects of converting enzyme inhibition in infants with congestive heart failure.J Pediatr 1990;117:668–670.

  6. 6.

    O'Rourke MF.Arterial Function in Health and Disease. New York: Churchill Livingstone, 1982:276.

  7. 7.

    O'Rourke MF. Vascular impedance in studies of arterial and cardiac function.Physiol Rev 1982;62:570–623.

  8. 8.

    Milnor WR. Arterial impedance as ventricular afterload.Circ Res 1975;36:565–570.

  9. 9.

    Little RC, Little WC. Cardiac preload, afterload, and heart failure.Arch Intern Med 1982;142:819–822.

  10. 10.

    Murgo JP, Westerhof N, Giolma JP, et al. Aortic input impedance in normal man: Relation to pressure wave forms.

  11. 11.

    Yaginuma T, Noda T, Tsuchiya M, et al. Interaction of left ventricular contraction and aortic input impedance in experimental and clinical studies.Jpn Circ J 1985;49:206–214.

  12. 12.

    Westerhof N, Sipkema P, Van Den Bos GC, et al. Forward and backward waves in the arterial system.Cardiovasc Res 1972;6:648–656.

  13. 13.

    Brodie BR, Mclaurin LP, Grossman W. Combined hemodynamic ultrasonic method for studying left ventricular wall stress.Am J Cardiol 1976;37:864–870.

  14. 14.

    Colan ST, Borow KM, Neumann A. Left ventricular end-systolic wall stress-velocity of fiber shortening relation: A load-independent index of myocardial contractility.J Am Coll Cardiol 1984;4:715–724.

  15. 15.

    O'Rourke MF, Yaginuma T. Wave reflections and the arterial pulse.Arch Intern Med 1984;144:366–371.

  16. 16.

    Yaginuma T, Avolio A, O'Rourke M, et al. Effect of glycerltrinitrate on peripheral arteries alters left ventricular hydraulic load in man.Cardiovasc Res 1986;20:153–160.

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Correspondence to Hideki Endo MD.

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Endo, H., Shiraishi, H. & Yanagisawa, M. Afterload reduction by hydralazine in children with a ventricular septal defect as determined by aortic input impedance. Cardiovasc Drug Ther 8, 161–166 (1994).

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Key Words

  • ventricular septal defect
  • hydralazine
  • afterload wall stress
  • aortic input impedance