Superior Mesenteric Artery Peak Systolic Velocity Research Articles

Superior mesenteric artery Doppler parameters in the evaluation of fetal hyperechogenic bowel.

The aim of this study was to evaluate the efficacy and clinical effects of superior mesenteric artery (SMA) Doppler indices such as the systole diastole ratio (S/D), Pulsatility (PI), and resistance index (RI) in the diagnosis of hyperechogenic bowel. A total of 133 pregnant women, including 66 with hyperechogenic bowel and 67 controls, were enrolled in the study. All participants were evaluated in the second trimester by an experienced obstetrician. Doppler measurements were performed, including superior mesenteric artery peak systolic velocity, S/D ratio, PI, and RI. Statistical analysis was conducted to compare the Doppler parameters between the hyperechogenic bowel and control groups. No significant differences were found between the hyperechogenic bowel and control groups in terms of age, body mass index, gestational week, and fetal measurements. While SMA peak systolic velocity (PSV) showed no significant difference between the groups (p = 0.074), the S/D ratio (4.01 ± 0.59 vs. 3.27 ± 0.57, p = 0.0001), PI (1.51 ± 0.15 vs. 1.29 ± 0.06, p = 0.0001), RI (0.76 ± 0.05 vs. 0.67 ± 0.04, p = 0.0001) were significantly higher in the hyperechogenic bowel group compared to the control group. Screening tests based on Doppler parameters also demonstrated significant differences. The S/D ratio, PI, and RI exhibited good to excellent diagnostic accuracy, as indicated by the area under the curve values. Pregnant women with a high RI value of 0.72 were 101 times more likely to be diagnosed with HB. The odds ratio (OR) for diagnosing HB is 101.66 (CI 95%, 31.04-332.97). Doppler indices, specifically the S/D ratio, PI, and RI, showed strong predictive ability and diagnostic accuracy in identifying cases of hyperechogenic bowel. These findings suggest that Doppler ultrasound can serve as a valuable tool for evaluating hyperechogenic bowel and may provide important clinical implications. Further diagnostic tests are warranted to determine the underlying cause of hyperechogenic bowel in individual cases.

Superior Mesenteric Artery Blood Flow in Parenterally Fed Versus Enterally Fed Preterm Infants.

The aim of the study was to compare superior mesenteric artery (SMA) flow in premature infants with parenteral and enteral nutrition. A prospective study was conducted on 2 groups of preterm infants with gestational age of 280/7 to 366/7 weeks: group 1 did not qualify for early enteral feeds and received parenteral nutrition (PN), and group 2 received early enteral feeding. SMA peak systolic velocity (PSV), end diastolic velocity (EDV), and pulsatility index (PI) were measured using Doppler ultrasound before starting feeds at day 1 and at day 5. The study recruited 40 infants; 20 in each group. At baseline, PSV, EDV, and PI did not differ between groups. At day 5, enteral nutrition was associated with significant increases in PSV (91.53 ± 29.15 vs 65.49 ± 19.18, P = 0.003) and EDV (15.91 ± 7.01 vs 11.65 ± 5.58, P = 0.026) and a decrease in PI (1.28 ± 0.40 vs 2.48 ± 0.83, P < 0.001). Regression analysis to control for confounders showed enterally fed infants to have increased PSV (adjusted odds ratio [aOR] = 25.45; 95% confidence interval [CI]: 8.53-42.38, P = 0.004) and EDV (aOR 8.630; 95% CI: 2.987-14.273, P = 004) and decreased PI (aOR = -1.133; 95% CI: -1.603 to -0.664, P < 0.001). Infants in the PN group later developed more frequent feeding intolerance when compared with the enterally fed group (65% vs 15%, respectively, P < 0.001). In preterm neonates, early EF is associated with increased SMA blood flow, decreased vascular intestinal resistance, and less frequent incidence of feeding intolerance.

Sonographic criteria for the evaluation of dietary compliance of children with celiac disease

Aim: Although the only known way to avoid complications like iron deficiency anemia, short stature in celiac disease is a strict gluten-free diet, it is a known fact that not all patients follow the diet. Diet compliance is practically evaluated with serum antibodies, such as tissue transglutaminase antibody. The aim of this study was to evaluate the contribution of less invasive ultrasound and Doppler ultrasound in evaluating dietary compliance in celiac patients.Materials and Methods: Twenty-five male and 47 female cases aged five to 17 years were included in the study. Seventy-two patients diagnosed with celiac disease and followed up were divided into two groups according to dietary compliance based on the results of tissue transglutaminase IgA antibody. Pericardial fluid, hepatosteatosis, mesenteric lymphadenopathy, intraabdominal free fluid, small intestine diameter, small intestine wall thickness and gallbladder volume, superior mesenteric artery (SMA) diameter, portal vein diameter, SMA peak systolic velocity, and portal vein velocity were measured on ultrasound. The differences between the groups were statistically compared.Results: The frequency of mesenteric lymphadenopathy, superior mesenteric artery diameter, SMA peak systolic velocity, and portal vein velocity were increased in children who did not follow the recommended diet. There was no significant difference between the groups in terms of hyperperistalsis, gallbladder volume, and portal vein diameter. Pericardial fluid, fatty liver, small intestine dilatation, and increased intestinal wall thickness were not detected in either group.Conclusion: Ultrasound can play an important role in the follow up of children with celiac disease. It can provide clinicians with an insight into the dietary compliance of these cases.

Doppler ultrasonographic evaluation of celiac and mesenteric arteries in subjects with sickle cell disease

Vasculopathy, as occurring in sickle cell disease (SCD), can affect celiac and mesenteric arteries and result in stenosis, with elevated peak systolic velocity (PSV) on Doppler ultrasonography. In six subjects with confirmed SCD in steady state, routine Doppler ultrasonographic examination discovered features of celiac artery (CA) or superior mesenteric artery (SMA) stenosis with CA PSV >200 cm/s (median = 222.8 cm/s; range = 201.5-427.1 cm/s) and/or SMA PSV >275 cm/s (median 183.2 cm/s; range = 87.8-289.3 cm/s). Among the six subjects, five had elevated soluble P-selectin values (median 72.55 ng/mL), while all six (100%) had elevated cystatin C levels (median 4.15 mg/L). Peripheral oxygen saturation was suboptimal in five subjects. All subjects had low hemoglobin concentration levels (median 8.5 g/dL) while four had elevated white blood cell count. Although vaso-occlusive crises result from microvessel occlusion, these findings at the macrovascular level suggest that SCD patients may also be vulnerable to mesenteric ischemic injury, especially in the setting of anemic heart failure from hemolysis.

IF08. Fate of the Unstented Superior Mesenteric Artery in Fenestrated Endovascular Aortic Aneurysm Repair

The objective of this study was to evaluate the patency of the unstented superior mesenteric artery (SMA) after fenestrated EVAR (F-EVAR) using duplex ultrasound (DUS) and computed tomography angiography (CTA). Patients with SMA fenestrations or crossing struts were identified from a database of patients who underwent F-EVAR at our institution between 2011 and 2017 as part of an investigational device exemption clinical trial (NCT01538056). Mesenteric DUS and CTA data were obtained at baseline and at 30 days, 6 months, and annually out to 5 years. The DUS parameter of SMA peak systolic velocity (PSV) of 275 cm/s was used to detect 70% SMA stenosis. CTA was used to evaluate the patency of the SMA when DUS PSV was elevated or if DUS was not performed. There were 107 patients who underwent endograft placement involving the SMA in association with F-EVAR. There were 87 SMA fenestrations and 20 bare-metal struts crossing the SMA; 79 patients had baseline and at least 30-day follow-up DUS SMA PSV measurements (64 fenestrations, 15 struts). Mean follow-up was 18.6 months (range, 30 days-5 years). SMA PSVs are listed in the Table. Mean PSVs remained well below the threshold velocity of 275 cm/s for native atherosclerotic 70% SMA stenosis. Nine patients had at least one SMA PSV >275 cm/s during follow-up. All were observed and showed no subsequent clinical sequelae. All patients had at least 30-day follow-up with CTA, and all had widely patent SMAs at last follow-up. Mean total seal zone length was 41.4 mm. There was a single secondary intervention for asymptomatic SMA stenosis requiring stent placement 1 year after F-EVAR. There were no Type IA endoleaks and no endoleaks related to SMA fenestrations. Five patients of the entire cohort (4.7%) required SMA stenting at the index procedure. Three of these patients had prior EVAR (n =2) or open repair (n = 1), One patient had a pre-existing critical SMA stenosis and underwent planned SMA stenting, and in one patient, the graft was deployed imprecisely and low, and the SMA was successfully stented from a brachial approach. The unstented SMA in association with F-EVAR remains widely patent in the presence of fenestrations or struts and is not associated with endoleaks. The need for adjunctive SMA stenting may be related to prior aortic intervention and case complexity. Follow-up DUS and CTA surveillance confirms that SMA patency remains in the normal or <70% stenosis range after F-EVAR regardless of whether it is encompassed by a large fenestration or crossing struts.TableSuperior mesenteric artery (SMA) peak systolic velocity (PSV)Fenestrations (n = 64)Struts (n = 15)Overall mean PSV (N = 79)Baseline128 ± 57153 ± 41133 ± 5530 Days115 ± 56155 ± 63123± 596 Months121 ± 80128 ± 82122 ± 801 Year131 ± 7799 ± 55124 ± 732 Years138 ± 89124 ± 58134 ± 813 Years145 ± 11399 ± 63129 ± 1004 Years134 ± 112120 ± 61129 ± 965 Years96 ± 61191 ±147122 ± 90Values are reported as mean ± standard deviation. Open table in a new tab

Duplex ultrasound in the early diagnosis of acute mesenteric ischemia: a longitudinal cohort multicentric study.

Acute mesenteric ischemia (AMI) is a life-threatening condition requiring time-dependent treatment; thus, early recognition may improve outcomes. We hypothesized that clinician-performed mesenteric vessels duplex ultrasound (DUS) could facilitate early identification of patients with AMI in high-risk patients presenting with abdominal pain. This was a single-operator, observational, prospective cohort study. Patients aged at least 65 presenting to Emergency Departments with acute abdominal pain and no clear diagnosis after an initial work-up were enrolled. All patients underwent multidetector computed tomography and these findings provided the reference standard in this study. DUS of the celiac artery and superior mesenteric artery (SMA) were obtained to measure the peak systolic velocity (PSV) and were performed within 24 h of admission. PSVs outside the normal range were considered to indicate AMI. Of 49 patients identified, 47 were consented to enrollment and diagnostic images were obtained in 45 (96%). Fifteen patients (33%) had AMI (six occlusive, nine nonocclusive disease). Among these, 12 (80%) had abnormal DUS velocities. SMA PSV showed a sensitivity of 78.57% [95% confidence interval (CI): 49.2-95.34], a specificity of 64.52% (95% CI: 45.37-80.77), a positive predictive value of 50% (95% CI: 28.22-71.78), and a negative predictive value of 86.96% (95% CI: 66.41-97.22) for AMI. DUS had a sensitivity of 100%, a specificity of 64%, and a negative predictive value of 100% for occlusive AMI. Assessment of celiac artery PSV did not improve diagnostic performance. In this single-operator pilot study, mesenteric vessel DUS was performed successfully in the Emergency Department, with a high proportion of diagnostic images obtained. A normal SMA PSV was associated with a low risk of occlusive AMI.

Intestinal blood flow by Doppler ultrasound: the impact of clarithromycin treatment for feeding intolerance in preterm neonates

Objective: To compare the blood flow velocities of superior mesenteric artery (SMA) before versus after clarithromycin treatment for feeding intolerance in very low-birth weight infants.Methods: A prospective study was conducted in a group of infant <1500 g with feeding intolerance who received clarithromycin 7.5 mg/kg/dose bid. Before and at the third day of the clarithromycin therapy, SMA blood flow velocity was measured with Doppler ultrasound.Results: SMA peak systolic velocity (PSV) and mean systolic velocity (MV) on the third day of the treatment was found significantly higher than the initial measurement (p = 0.013 and p = 0.027, respectively). End diastolic velocity of the SMA did not change with clarithromycin therapy (p = 0.113). There were no significant changes about pulsatility and resistive index of SMA with regard to clarithromycin therapy.Conclusion: Clarithromycin effects the splanchnic circulation. The rise in PSV and MV in SMA is remarkable. These results suggest that the splanchnic blood flow increases significantly after clarithromycin usage.

Mesenteric stenosis, collaterals, and compensatory blood flow

The mesenteric circulation has an extensive collateral network. Therefore, stenosis in one or more mesenteric arteries does not necessarily lead to symptoms. The objective of this study was to determine the effect of collateral flow on celiac artery (CA) and superior mesenteric artery (SMA) duplex parameters. Between 1999 and 2007, a cohort of 228 patients analyzed for suspected chronic mesenteric syndrome was studied. Stenosis of the mesenteric vessels and collateral flow patterns were identified on angiography and categorized. The effect of stenosis in one mesenteric vessel and the presence of collaterals from the other unaffected vessel was examined in both the CA and SMA. Stenosis of the CA resulted in a significantly higher peak systolic velocity (PSV) and end-diastolic velocity in the normal SMA without stenosis. This was also found for the CA without stenosis in the presence of a stenosis of the SMA. An incremental effect of the severity of the CA stenosis was found with a mean SMA PSV of 158cm/s when normal and 259cm/s when occluded. The presence of collaterals had a clear effect on duplex parameters of the angiographically normal SMA. In the presence of collaterals and a 70% CA stenosis, the PSV in the normal SMA was significantly higher (P= .025). This study shows that stenosis in either the CA or SMA increases flow velocities in the other unaffected mesenteric artery. This increase was correlated with the presence of collaterals. Collaterals and stenoses in one of the mesenteric arteries may lead to mimicking or overgrading of stenosis in the other mesenteric artery.

Intestinal Blood Flow by Doppler Ultrasound: The Impact of Gestational Age and Time from First Enteral Feeding in Preterm Neonates

To explore whether superior mesenteric artery (SMA) peak systolic velocity (PSV) on Doppler ultrasound varies by gestational age (GA) and time from first enteral feeding and has an impact on feeding intolerance. Preterm neonates were assigned to three GA groups at birth, group I: 31 to 356/7 weeks, group II: 27 to 306/7 weeks, and group III: ≤ 266/7 weeks. SMA PSV and clinical and feeding parameters were assessed before and after enteral feed, with the first enteral feed designated as time 1, time 2 = 1 to 4 days (after first feed), time 3= 5 to 7 days, time 4 = 8 to 14 days, and time 5 = 15 to 28. Forty-one patients completed the study (group I: n = 17, group II: n = 12, group III: n = 12). There was no significant difference in SMA PSV change after feeding between groups at the start of enteral feeding (p = 0.12). There were differences in change in SMA PSV after feeding at times 2, 3 and 5 (p = 0.003, p = 0.004, p = 0.009, respectively). Patients with feeding intolerance exhibited a smaller increase in SMA PSV after feeding. There were significant differences in PSV by GA group. SMA PSV change after feeding was lower in patients who had feeding intolerance compared with those who did not.

Application of duplex ultrasound imaging in determining in-stent stenosis during surveillance after mesenteric artery revascularization

Currently, there are no well-established duplex ultrasound (DUS) criteria for the evaluation of the mesenteric arteries after stenting for occlusive disease. Previous studies suggested DUS velocity criteria in the native superior mesenteric artery (SMA) overestimate stenosis in stented arteries, but most studies have not evaluated DUS imaging after SMA stenting longitudinally. This study was undertaken to determine the accuracy of DUS after mesenteric artery revascularization and, in particular, to evaluate the utility of DUS imaging for the detection of in-stent stenosis (ISS) of the SMA. A retrospective record review was performed for all patients who underwent SMA stenting for chronic mesenteric ischemia at a single institution from January 2004 to May 2011. Mesenteric artery occlusive disease resulted in 24 patients undergoing mesenteric stenting of the SMA alone (n = 20) or the SMA and celiac artery simultaneously (n = 3). The mean ± standard deviation peak systolic velocity (PSV) in 13 prestent DUS images of the SMA was 464 ± 130 cm/s. Prestenting angiography revealed an average SMA stenosis of 79% ± 14%. After stenting, completion angiography in each case revealed <20% residual stenosis. No significant correlation was identified between SMA PSV and angiographic stenosis before and after stenting (P > .05). Follow-up SMA DUS imaging showed an average PSV of 335 ± 138 cm/s at 0.9 ± 1.5 months, 360 ± 143 cm/s at 4.8 ±2.6 months, and 389 ± 95 cm/s at 14.4 ± 5.1 months. A significant difference existed between the prestent and the first poststent mean SMA PSV (P < .05), but no significant difference existed between each poststenting interval. Eight reinterventions for SMA ISS were performed, with a mean elevated in-stent SMA PSV of 505 ± 74 vs 341 ± 145 cm/s in patients who did not undergo reintervention. Angiography before the eight reinterventions demonstrated an average SMA ISS of 53% ± 25%. In-stent SMA PSV decreased from 505 ± 74 to 398 ± 108 cm/s after the reintervention (P < .05). Consistent with other reports, our data demonstrate the PSV in successfully stented SMAs remains higher than the PSV threshold of 275 cm/s used for the diagnosis of high-grade native SMA stenosis. In addition, in-stent SMA PSVs did not significantly change over DUS surveillance for patients who did not undergo reintervention. Thus, obtaining a baseline DUS early after mesenteric stenting should be considered to compare future surveillance DUS. An increase above this baseline or an in-stent SMA PSV approaching 500 cm/s should be considered suspicious for ISS, but larger prospective studies will be required to validate these preliminary findings.

The values of mesenteric and celiac arterial blood flow parameters in healthy preterm newborns

Background: Mesenteric and celiac arterial blood flow parameters may be useful in the diagnosis of abdominal complaints. In differential diagnosis necrotizing enterocolitis (NEC) should always be considered, especially in preterms infants. Incidence of this disease comes to 2.5/1000 live births, but mortality reaches 20-50%. Early diagnosis is of great importance in early stages of NEC, to avoid surgical treatment and peritonitis. It may decrease mortality in this group of patients and improve further quality of life. The aim of the study was to evaluate values of mesenteric and celiac arterial blood flow assessment during abdominal ultrasonography in healthy preterms. Method: Study group consists of 50 healthy preterms. Ultrasound of the abdomen was performed in all newborns and blood flow in superior mesenteric artery (SMA) and celiac artery (CA) was assessed: peak systolic velocity (PSV), pulsation index (PI) and resistance index (RI). Results: Mean values were obtained: SMA PSV= 58 cm/s (range 32.3-84.2 cm/s); CA PSV = 56 cm/s (range 14,3-126,0 cm/s), SMA PI = 2.0 (range 1.21-4.52); CA PI = 1.65 (range 0.66-3.13); SMA RI = 0.86 (range 0.71-1,11); CA RI = 0.79 (range 0.5-1.13). Conclusions: These measurements are physiological values for a group of preterm infants and might become reference values and be useful in the diagnosis of NEC.

Screening for mesenteric vascular insufficiency and follow-up of mesenteric artery bypass procedures.

Duplex ultrasonography is the preferred noninvasive screening test for superior mesenteric artery (SMA) and celiac artery (CA) stenosis. Although postprandial increases in SMA peak systolic velocity (PSV) are known to occur, the principal duplex criteria for hemodynamically significant SMA and CA stenosis are based on fasting flow velocities. In the SMA, a PSV > or =275 cm/s predicts a > or =70% angiographic stenosis with a sensitivity of 92% and a specificity of 96%, whereas a CA PSV of > or =200 cm/sec predicts a > or =70% stenosis with a sensitivity of 87% and a specificity of 80%. Patients with appropriate symptoms of chronic visceral ischemia and a duplex scan showing high-grade stenosis of the SMA, especially when combined with CA stenosis, should have a confirmatory mesenteric angiogram. This approach will facilitate prompt intervention in these patients. If the duplex examination indicates widely patent mesenteric arteries, alternative diagnoses should be investigated. Other applications of mesenteric duplex scanning include evaluation of median arcuate ligament syndrome and postoperative surveillance of mesenteric artery revascularizations.

Usefulness of fasting and postprandial duplex ultrasound examinations for predicting high-grade superior mesenteric artery stenosis

A fasting duplex ultrasound examination of the superior mesenteric artery (SMA) accurately detects high-grade (> 70%) stenosis. It has been postulated that postprandial mesenteric duplex scanning may further stratify stenosis and improve the ability of a fasting examination to detect a high-grade stenosis. We performed fasting and postprandial duplex scanning of 25 healthy controls and 80 patients with vascular disease undergoing aortography to determine whether postprandial mesenteric duplex scanning provides information beyond a fasting study alone. Patients with vascular disease were divided into three groups based on lateral aortography results: group 1, 0% to < 30% SMA stenosis (n = 61); group 2, 30% to < 70% stenosis (n = 10); and group 3, 70% to 99% stenosis (n = 9). Fasting mesenteric duplex scanning was defined as positive for 70% to 99% stenosis if the peak systolic velocity (PSV) was > or = 275 cm/s. The ability of either fasting or postprandial mesenteric duplex scanning, and their combination, to predict high-grade (70% to 99%) SMA stenosis was determined using angiographic control. Mean fasting SMA PSV did not differ among controls and groups 1 and 2. Postprandial PSV increased significantly in all groups, but was not different among controls and groups 1 and 2. Mean fasting PSV was significantly higher, and the postprandial increase in PSV significantly lower, in group 3 compared with controls and with groups 1 and 2. Fasting mesenteric duplex scanning predicted 70% to 99% SMA stenosis, with 89% sensitivity, 97% specificity, 80% positive predictive value, 99% negative predictive value, and 96% accuracy. Corresponding values for postprandial scanning were 67%, 94%, 60%, 96%, 91%, and for the combination of normal fasting and postprandial scanning 67%, 100%, 100%, 96%, 96%, respectively. Postprandial increases in SMA PSVs are blunted in patients with high-grade stenosis, but feeding velocities do not stratify between lesser degrees of stenosis. Both fasting and postprandial PSVs identify high-grade (> 70%) stenosis. Their combination marginally improves fasting duplex scan specificity and positive predictive value. Postprandial scanning is not necessary for the diagnosis of high-grade stenosis if a fasting study identifies a PSV > or = 275 cm/s. The combination of normal fasting and postprandial mesenteric duplex ultrasound scanning may effectively rule out high-grade SMA stenosis.

Duplex ultrasonography in the diagnosis of celiac and mesenteric artery occlusive disease

Duplex ultrasound criteria for the diagnosis of celiac and superior mesenteric artery (SMA) occlusive disease have not been well defined. We performed a blinded retrospective comparison of mesenteric duplex data with arteriography in 24 consecutive patients who underwent both studies. Arteriography revealed that eight superior mesenteric arteries were normal; five were minimally stenotic; eight had stenoses greater than or equal to 50%, and three were occluded. Nine celiac arteries were normal or minimally stenotic; 12 had stenoses greater than or equal to 50%, and three were occluded. Duplex scans were obtained after an overnight fast. In normal superior mesenteric arteries, peak systolic velocity (PSV) was 134 +/- 18 cm/sec and end-diastolic velocity (EDV) was 24 +/- 4 cm/sec. Superior mesenteric artery PSV in patients with minimal or no stenosis (171 +/- 22 cm/sec) was less than PSV in patients with severe (greater than 50%) stenosis (299 +/- 40 cm/sec, p = 0.006), and less than PSV in patients with patent superior mesenteric arteries who underwent revascularization (366 +/- 86 cm/sec, p = 0.017). Similarly, EDV was elevated in superior mesenteric arteries with severe stenosis (78 +/- 11 cm/sec, p = 0.001) and in patients who underwent revascularization (111 +/- 19 cm/sec, p less than 0.001) compared to those with less than 50% stenosis (30 +/- 6 cm/sec, p = 0.001). An EDV greater than 45 cm/sec was the best indicator of severe stenosis (sensitivity, 1.0; specificity, 0.92). Peak systolic velocity greater than 300 cm/sec was less sensitive (0.63), but highly specific (1.0) for severe superior mesenteric artery stenosis.(ABSTRACT TRUNCATED AT 250 WORDS)