Bisferiens peaks in the radial artery pressure wave in newborn infants: a sign of patent ductus arteriosus.

Previously, we found evidence that radial artery pressure wave forms in newborns represent central aortic wave forms, provided that pressure is measured with adequate accuracy. Therefore, we postulated that the neonatal radial artery wave form, like the adult aortic wave form, may contribute to cardiovascular diagnosis. We investigated whether radial artery wave forms in infants suffering from patent ductus arteriosus (PDA) are different from the wave forms as seen without the presence of PDA. We studied 34 newborn infants with a radial artery line and with the possible clinical diagnosis of PDA with left-to-right shunt. On the basis of echocardiographic examination to assess PDA, these infants were divided in two groups: infants with PDA (n = 24) and without PDA (n = 10). In 15 out of 24 infants with PDA, recordings were repeated after ductal closure. Blood pressure measurement was performed with a high fidelity cathetermanometer system using a tip-transducer (natural frequency 95 Hz, damping coefficient 0.15). Contour analysis was performed by describing morphology of the waves during PDA and without PDA. In 23 out of 24 infants with PDA, a pulsus bisferiens was present: two peaks separated by a deep cleft. The average pressure difference between the first pressure peak and the cleft [delta Ppeak1] was 0.35 +/- 0.19 kPa, and the average difference between the cleft and the second pressure peak [delta Ppeak2] was 0.44 +/- 0.23 kPa. the ratio of mean magnitude of delta Ppeak1 and delta Ppeak2 was 0.81 +/- 0.26. None of the 10 infants without PDA showed pulsus bisferiens.(ABSTRACT TRUNCATED AT 250 WORDS)