TY - JOUR
T1 - Splanchnic-mesenteric capacitance bed in the postural tachycardia syndrome (POTS)
AU - Tani, Hiroshi
AU - Singer, Wolfgang
AU - McPhee, Benjamin R.
AU - Opfer-Gehrking, Tonette L.
AU - Haruma, Ken
AU - Kajiyama, Goro
AU - Low, Phillip A.
N1 - Funding Information:
This study was supported in part by the National Institutes of Health (PO1 NS32352; M01 RR00585) and Mayo Funds.
PY - 2000/12/28
Y1 - 2000/12/28
N2 - Background: Gastroenterologic symptoms are common in the postural tachycardia syndrome (POTS), and postprandial worsening of orthostatic symptoms often occurs. We, therefore, investigated splanchnic-mesenteric vasoregulation in POTS. Subjects and methods: Eleven patients with POTS (one man, 10 women, 29.4±7.7 (S.D.) years) and 10 controls (two men, eight women, 27.9±5.6 years) participated in this study. The protocol included 5 min of 70° head-up tilt (HUT) before and after a liquid meal, as well as 1.5 min of hyperventilation. Blood pressure (BP), heart rate (HR), endtidal CO2, and cardiovascular indices derived from thoracic electrical bioimpedance were continuously monitored. Superior mesenteric artery (SMA) blood flow was measured by real time Doppler ultrasound and analyzed off-line. Cross-sectional area of SMA (SMA-area) and time-averaged velocity (SMA-TAV) were measured; SMA blood flow (SMA-BF) and vascular resistance (SMA-VR) were derived. Results: The following significant results were found: at supine rest, the POTS group had higher HR, BP, SMA-TAV and SMA-BF and a lower SMA-VR than the control group. HUT resulted in a reduction of pulse pressure, CO2 level, SMA-area, SMA-TAV and SMA-VF and increment of HR and SMA-VR in both groups. The POTS group underwent greater increment of HR and greater reduction of CO2 than controls. Hyperventilation induced increment of HR and cardiac index (CI) and reduction of SMA-VR in controls; no significant change occurred in POTS. The test meal induced increments of HR, CI, SMA-area, SMA-TAV and SMA-VF and reduction of SMA-VR in patients and controls for both supine rest and HUT. Conclusion: The main novel observations of increased resting SMA-BF, SMA-TAV supine, and reduced SMA-VR when compared with controls support the notion that there is excessive splanchnic capacity (pooling) at rest in POTS. Copyright (C) 2000 Elsevier Science B.V.
AB - Background: Gastroenterologic symptoms are common in the postural tachycardia syndrome (POTS), and postprandial worsening of orthostatic symptoms often occurs. We, therefore, investigated splanchnic-mesenteric vasoregulation in POTS. Subjects and methods: Eleven patients with POTS (one man, 10 women, 29.4±7.7 (S.D.) years) and 10 controls (two men, eight women, 27.9±5.6 years) participated in this study. The protocol included 5 min of 70° head-up tilt (HUT) before and after a liquid meal, as well as 1.5 min of hyperventilation. Blood pressure (BP), heart rate (HR), endtidal CO2, and cardiovascular indices derived from thoracic electrical bioimpedance were continuously monitored. Superior mesenteric artery (SMA) blood flow was measured by real time Doppler ultrasound and analyzed off-line. Cross-sectional area of SMA (SMA-area) and time-averaged velocity (SMA-TAV) were measured; SMA blood flow (SMA-BF) and vascular resistance (SMA-VR) were derived. Results: The following significant results were found: at supine rest, the POTS group had higher HR, BP, SMA-TAV and SMA-BF and a lower SMA-VR than the control group. HUT resulted in a reduction of pulse pressure, CO2 level, SMA-area, SMA-TAV and SMA-VF and increment of HR and SMA-VR in both groups. The POTS group underwent greater increment of HR and greater reduction of CO2 than controls. Hyperventilation induced increment of HR and cardiac index (CI) and reduction of SMA-VR in controls; no significant change occurred in POTS. The test meal induced increments of HR, CI, SMA-area, SMA-TAV and SMA-VF and reduction of SMA-VR in patients and controls for both supine rest and HUT. Conclusion: The main novel observations of increased resting SMA-BF, SMA-TAV supine, and reduced SMA-VR when compared with controls support the notion that there is excessive splanchnic capacity (pooling) at rest in POTS. Copyright (C) 2000 Elsevier Science B.V.
KW - Orthostatic intolerance
KW - Peripheral resistance
KW - Splanchnic
KW - Splanchnic pooling
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U2 - 10.1016/S1566-0702(00)00205-8
DO - 10.1016/S1566-0702(00)00205-8
M3 - Article
C2 - 11269915
AN - SCOPUS:0034727922
SN - 1566-0702
VL - 86
SP - 107
EP - 113
JO - Autonomic Neuroscience: Basic and Clinical
JF - Autonomic Neuroscience: Basic and Clinical
IS - 1-2
ER -