Abstract
Bifurcation is a basic form of vascular connection. It is composed of a parent vessel of diameter d0, and two daughter vessels, d1 and d2, where d0 > d1 ≥ d2. Optimal values for the bifurcation area ratio, β = (d1/2 + d2/2)/d0/2 and the junction exponent, x, in d0/(x) = d1/(x) + d2/(x), are postulated to be universal in nature. However, we have hypothesized that the perinatal pulmonary arterial circulation is an exception. Arterial diameters were measured in pulmonary vascular casts of a fetal lamb (140 days gestation/145 days term) and a neonatal lamb (1 day old). The values for β and x were evaluated in 10,970 fetal and 846 neonatal bifurcations sampled from the proximal and intermediate arterial regions. Mean values and confidence intervals (CI) for the fetus were β = 0.890 (0.886-0.895 CI) and x = 1.75 (1.74-1.76 CI); and for the newborn were β = 0.913 (0.90-0.93 CI) and x = 1.79 (1.75-1.82 CI). These values are significantly different from Murray's law (β > 1, x = 3) or the West-Brown-Enquist law (β = 1, x = 2). Therefore, perinatal pulmonary bifurcation design appears to be distinctive and exceptional. The decreasing cross-sectional area with branching leads to the hemodynamic consequence of shear stress amplification. This structural organization may be important for facilitating vascular development at low flow rates; however, it may be the origin of unstable reactivity if elevated blood flow and pressure occurs.
| Original language | English (US) |
|---|---|
| Journal | American Journal of Physiology - Heart and Circulatory Physiology |
| Volume | 279 |
| Issue number | 6 48-6 |
| State | Published - 2000 |
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Keywords
- Branching complexity
- Heterogeneity
- Pulmonary arterial morphometry
ASJC Scopus subject areas
- Physiology
- Physiology (medical)
Cite this
Form and function of fetal and neonatal pulmonary arterial bifurcations. / Bennett, Stephen H.; Eldridge, Marlowe W.; Zaghi, Daniel; Zaghi, Shaaron E.; Milstein, Jay M; Goetzman, Boyd W.
In: American Journal of Physiology - Heart and Circulatory Physiology, Vol. 279, No. 6 48-6, 2000.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Form and function of fetal and neonatal pulmonary arterial bifurcations
AU - Bennett, Stephen H.
AU - Eldridge, Marlowe W.
AU - Zaghi, Daniel
AU - Zaghi, Shaaron E.
AU - Milstein, Jay M
AU - Goetzman, Boyd W.
PY - 2000
Y1 - 2000
N2 - Bifurcation is a basic form of vascular connection. It is composed of a parent vessel of diameter d0, and two daughter vessels, d1 and d2, where d0 > d1 ≥ d2. Optimal values for the bifurcation area ratio, β = (d1/2 + d2/2)/d0/2 and the junction exponent, x, in d0/(x) = d1/(x) + d2/(x), are postulated to be universal in nature. However, we have hypothesized that the perinatal pulmonary arterial circulation is an exception. Arterial diameters were measured in pulmonary vascular casts of a fetal lamb (140 days gestation/145 days term) and a neonatal lamb (1 day old). The values for β and x were evaluated in 10,970 fetal and 846 neonatal bifurcations sampled from the proximal and intermediate arterial regions. Mean values and confidence intervals (CI) for the fetus were β = 0.890 (0.886-0.895 CI) and x = 1.75 (1.74-1.76 CI); and for the newborn were β = 0.913 (0.90-0.93 CI) and x = 1.79 (1.75-1.82 CI). These values are significantly different from Murray's law (β > 1, x = 3) or the West-Brown-Enquist law (β = 1, x = 2). Therefore, perinatal pulmonary bifurcation design appears to be distinctive and exceptional. The decreasing cross-sectional area with branching leads to the hemodynamic consequence of shear stress amplification. This structural organization may be important for facilitating vascular development at low flow rates; however, it may be the origin of unstable reactivity if elevated blood flow and pressure occurs.
AB - Bifurcation is a basic form of vascular connection. It is composed of a parent vessel of diameter d0, and two daughter vessels, d1 and d2, where d0 > d1 ≥ d2. Optimal values for the bifurcation area ratio, β = (d1/2 + d2/2)/d0/2 and the junction exponent, x, in d0/(x) = d1/(x) + d2/(x), are postulated to be universal in nature. However, we have hypothesized that the perinatal pulmonary arterial circulation is an exception. Arterial diameters were measured in pulmonary vascular casts of a fetal lamb (140 days gestation/145 days term) and a neonatal lamb (1 day old). The values for β and x were evaluated in 10,970 fetal and 846 neonatal bifurcations sampled from the proximal and intermediate arterial regions. Mean values and confidence intervals (CI) for the fetus were β = 0.890 (0.886-0.895 CI) and x = 1.75 (1.74-1.76 CI); and for the newborn were β = 0.913 (0.90-0.93 CI) and x = 1.79 (1.75-1.82 CI). These values are significantly different from Murray's law (β > 1, x = 3) or the West-Brown-Enquist law (β = 1, x = 2). Therefore, perinatal pulmonary bifurcation design appears to be distinctive and exceptional. The decreasing cross-sectional area with branching leads to the hemodynamic consequence of shear stress amplification. This structural organization may be important for facilitating vascular development at low flow rates; however, it may be the origin of unstable reactivity if elevated blood flow and pressure occurs.
KW - Branching complexity
KW - Heterogeneity
KW - Pulmonary arterial morphometry
UR - http://www.scopus.com/inward/record.url?scp=0034537385&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0034537385&partnerID=8YFLogxK
M3 - Article
C2 - 11087263
AN - SCOPUS:0034537385
VL - 279
JO - American Journal of Physiology - Renal Fluid and Electrolyte Physiology
JF - American Journal of Physiology - Renal Fluid and Electrolyte Physiology
SN - 1931-857X
IS - 6 48-6
ER -