Postprandial superior mesenteric artery blood flow related to changes in peripheral pulse wave harmonics and heart rate: implications for wearable technology?

2021 ◽  
Author(s):  
Eamon Abdullah ◽  
Jordan B. Lee ◽  
Karambir Notay ◽  
Philip J. Millar
Keyword(s):  
Heart Rate ◽  
Blood Flow ◽  
Superior Mesenteric Artery ◽  
Mesenteric Artery ◽  
Pulse Wave ◽  
Caloric Intake ◽  
Wearable Technology ◽  
Harmonic Spectrum ◽  
Caloric Content ◽  
Peripheral Pulse

Postprandial superior mesenteric artery (SMA) blood flow is associated with the caloric content of a meal. Whether spectral analysis of a peripheral pulse wave or heart rate can model postprandial SMA blood flow is unclear. We hypothesized that altering the caloric content of a meal would evoke dose-response increases in postprandial SMA hyperemia and distinct changes in the pulse wave harmonic spectrum and heart rate. Twenty healthy subjects (10 male, 26±10 yrs) completed a randomized cross-over trial, comparing three meals (280, 560, or 840 kcal) on SMA blood flow (Doppler ultrasound), heart rate, and the 1st to 7th harmonic amplitudes (derived from a finger pulse wave). Supine SMA diameter and blood velocity were collected at baseline and every 15-minutes throughout 2 hours of postprandial recovery. SMA blood flow was smaller across all time points following meal 1 (280 kcal) compared to both meal 2 (560 kcal) and meal 3 (840 kcal) (All p<0.001), while meal 2 had attenuated responses compared to meal 3 at 60, 90, 105, and 120 minutes postprandial (All p<0.01). Distinct changes in heart rate and the amplitude of 2nd to 5th harmonics were observed between meals (All p<0.05). The changes in harmonic spectrum or heart rate explained 66-69% (adjusted r2) of the variance in postprandial SMA blood flow. These results provide proof-of-concept that easily obtained and non-invasive postprandial harmonic profiles or heart rate may be used to explain changes in SMA blood flow and exploited for the development of wearable technology to non-invasively track caloric intake.

Effects of variations in duodenal glucose load on blood pressure, heart rate, superior mesenteric artery blood flow and plasma noradrenaline in healthy young and older subjects

2011 ◽  
Vol 122 (6) ◽  
pp. 271-279 ◽  
Author(s):  
Laurence G. Trahair ◽  
Lora Vanis ◽  
Diana Gentilcore ◽  
Kylie Lange ◽  
Christopher K. Rayner ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Heart Rate ◽  
Blood Flow ◽  
Superior Mesenteric Artery ◽  
Mesenteric Artery ◽  
Clinical Problem ◽  
Vascular Conductance ◽  
Female Age ◽  
Older Subjects ◽  
Young Subjects

PPH (postprandial hypotension), leading to increased morbidity and mortality, is an important clinical problem, particularly in the elderly and individuals with autonomic dysfunction. The magnitude of the postprandial fall in BP (blood pressure) appears to be dependent on the rate of nutrient entry into the small intestine and may be related to changes in splanchnic blood flow and sympathetic nerve activity. We aimed at determining the comparative effects of different ID (intraduodenal) glucose loads on BP, HR (heart rate), SMA (superior mesenteric artery) flow and vascular conductance and plasma NA (noradrenaline) in ‘young’ and ‘older’ subjects. A total of 12 ‘young’ (six male and six female; age, 22.2±2.3 years) and 12 ‘older’ (six male and six female; age, 68.7±1.0 years) subjects, the latter who have been studied previously [Vanis, Gentilcore, Rayner, Wishart, Horowitz, Feinle-Bisset and Jones (2011) Am. J. Physiol. Regul. Integr. Comp. Physiol., 300, R1524–R1531], had measurements of BP, HR, SMA flow and plasma NA before, and during, ID infusions of glucose at 1, 2 or 3 kcal/min (‘G1’, ‘G2’ and ‘G3’) (where 1 kcal≈4.184 J), or ‘S’ (saline) for 60 min. In ‘young’ subjects, there was no change in BP during any of the four infusions. In contrast, in ‘older’ subjects, SBP (systolic BP) fell during ‘G2’, and ‘G3’ (P<0.005 for both), but not during ‘S’ or ‘G1’. In ‘young’ and ‘older’ subjects HR increased during ‘G2’ (P<0.05) and ‘G3’ (P<0.001), a response that was greater (P<0.05) in the young, but not during ‘S’ or ‘G1’. The rise in SMA flow and vascular conductance in response to ID glucose were load-dependent in both ‘young’ and ‘older’ subjects (P<0.001 for all), with no difference between them. Plasma NA rose in response to ‘G2’ and ‘G3’ (P<0.05) in the young, but in ‘G3’ (P<0.05) only in the ‘older’ subjects, with no difference between them. Hence, in response to small intestinal glucose infusions at 1, 2 and 3 kcal/min, ‘older’, but not ‘young’, subjects exhibit a comparable fall in BP in response to the two higher glucose loads, which may reflect an inadequate, compensatory, rise in HR, in the ‘older’ subjects, but not a greater increase in SMA conductance.

Effects of Oral Alcohol on Superior Mesenteric Artery Blood Flow in Normal Man, Horizontal and Tilted

1993 ◽  
Vol 84 (4) ◽  
pp. 419-425 ◽  
Author(s):  
S. Maule ◽  
K. Ray Chaudhuri ◽  
T. Thomaides ◽  
D. Pavitt ◽  
J. McCleery ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Heart Rate ◽  
Blood Flow ◽  
Body Weight ◽  
Cardiac Index ◽  
Superior Mesenteric Artery ◽  
Mesenteric Artery ◽  
Cardiovascular Effects ◽  
Normal Subjects ◽  
Head Up Tilt

1. The cardiovascular effects of oral alcohol (0.5 g/kg body weight diluted to 300 ml in sugar-free orange juice) were compared with those of placebo in 10 normal subjects. Measurements were made while the subjects were supine and horizontal for 45 min and after 10 min of 45° head-up tilt. 2. After alcohol, plasma alcohol levels rose from 1.9 ± 1.3 to 61.6 ± 6.5 mg/100 ml. After placebo, plasma alcohol levels did not increase. After alcohol and placebo, supine blood pressure was unchanged; heart rate, both supine and during tilt, rose after alcohol only. 3. After alcohol, superior mesenteric artery and digital skin blood flow increased and calculated vascular resistances fell. There was no change after placebo. 4. Forearm blood flow, forearm vascular resistance and cardiac index did not change in either phase, except for a fall in cardiac index during tilt but only after alcohol. 5. In conclusion, the acute ingestion of 0.5 g of alcohol/kg body weight in normal subjects raised heart rate and actively dilated the superior mesenteric artery and digital skin vessels. There was no effect on blood pressure, cardiac output and skeletal muscle vascular tone. During head-up tilt after alcohol, there was a tendency for blood pressure to fall with a compensatory rise in heart rate.

Hypotensive and Regional Haemodynamic Effects of Exercise, Fasted and after Food, in Human Sympathetic Denervation

1998 ◽  
Vol 94 (1) ◽  
pp. 49-55 ◽  
Author(s):  
Sharmini Puvi-Rajasingham ◽  
Gareth D. P. Smith ◽  
Adeola Akinola ◽  
Christopher J. Mathias
Keyword(s):  
Blood Pressure ◽  
Heart Rate ◽  
Mean Arterial Pressure ◽  
Arterial Pressure ◽  
Superior Mesenteric Artery ◽  
Vascular Resistance ◽  
Mesenteric Artery ◽  
Autonomic Failure ◽  
Sympathetic Denervation ◽  
Stroke Distance

1. In human sympathetic denervation due to primary autonomic failure, food and exercise in combination may produce a cumulative blood pressure lowering effect due to simultaneous splanchnic and skeletal muscle dilatation unopposed by corrective cardiovascular reflexes. We studied 12 patients with autonomic failure during and after 9 min of supine exercise, when fasted and after a liquid meal. Standing blood pressure was also measured before and after exercise. 2. When fasted, blood pressure fell during exercise from 162 ± 7/92 ± 4 to 129 ± 9/70 ± 5 mmHg (mean arterial pressure by 22 ± 5%), P < 0.0005. After the meal, blood pressure fell from 159 ± 8/88 ± 6 to 129 ± 6/70 ± 4 mmHg (mean arterial pressure by 22 ± 3%), P < 0.0001, and further during exercise to 123 ± 6/61 ± 3 mmHg (mean arterial pressure by 9 ± 3%), P < 0.01. The stroke distance—heart rate product, an index of cardiac output, did not change after the meal. During exercise, changes in the stroke distance—heart rate product were greater when fasted. 3. Resting forearm and calf vascular resistance were higher when fasted. Calf vascular resistance fell further after exercise when fasted. Resting superior mesenteric artery vascular resistance was lower when fed; 0.19 ± 0.02 compared with 032 ± 0.06, P < 0.05. After exercise, superior mesenteric artery vascular resistance had risen by 82%, to 0.53 ± 0.12, P < 0.05 (fasted) and by 47%, to 0.29 ± 0.05, P < 0.05 (fed). 4. On standing, absolute levels of blood pressure were higher when fasted [83 ± 7/52 ± 7 compared with 71 ± 2/41 ± 3 (fed), each P < 0.05]. Subjects were more symptomatic on standing post-exercise when fed. 5. In human sympathetic denervation, exercise in the fed state lowered blood pressure further than when fasted and worsened symptoms of postural hypotension.

Superior Mesenteric Artery Blood Flow Modifications During Off-Pump Coronary Surgery

2006 ◽  
Vol 82 (1) ◽  
pp. 62-67 ◽  
Author(s):  
Giuseppe Fiore ◽  
Nicola Brienza ◽  
Pasquale Cicala ◽  
Pasquale Tunzi ◽  
Nicola Marraudino ◽  
...  
Keyword(s):  
Blood Flow ◽  
Superior Mesenteric Artery ◽  
Mesenteric Artery ◽  
Coronary Surgery ◽  
Artery Blood Flow ◽  
Off Pump ◽  
Mesenteric Artery Blood Flow

Hemodynamic responses to glycols and to hemolysis

1969 ◽  
Vol 47 (6) ◽  
pp. 563-569 ◽  
Author(s):  
Keith MacCannell
Keyword(s):  
Blood Flow ◽  
Superior Mesenteric Artery ◽  
Renal Blood Flow ◽  
Mesenteric Artery ◽  
Direct Injection ◽  
Artery Blood Flow ◽  
Passive Response ◽  
Flow Through ◽  
Vascular Beds ◽  
Mesenteric Artery Blood Flow

Ethylene and propylene glycol both decrease renal blood flow in dogs while increasing flow through the superior mesenteric artery. The decrease in renal blood flow is not a passive response to dilatation of major vascular beds since it precedes the increment in superior mesenteric arterial flow and since it can be duplicated by direct injection of glycols into the renal artery. These rheological changes in response to glycols are at least partly due to hemolysis since intravenous injection of plasma from hemolyzed blood or of crystalline hemoglobin produces the same pattern of response, which is not blocked by phenoxybenzamine. However, the production of hemoglobinemia may not be the sole explanation for the vascular responses to the glycols, since a concentration of 2 %, which does not induce detectable hemolysis, still produces the characteristic increase in superior mesenteric artery blood flow.

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