| Title |
The impact of hematocrit on oxygenation-sensitive cardiovascular magnetic resonance
|
|---|---|
| Published in |
Critical Reviews in Diagnostic Imaging, July 2016
|
| DOI | 10.1186/s12968-016-0262-1 |
| Pubmed ID | |
| Authors |
Dominik P. Guensch, Gobinath Nadeshalingam, Kady Fischer, Aurelien F. Stalder, Matthias G. Friedrich |
| Abstract |
Oxygenation-sensitive (OS) Cardiovascular Magnetic Resonance (CMR) is a promising utility in the diagnosis of heart disease. Contrast in OS-CMR images is generated through deoxyhemoglobin in the tissue, which is negatively correlated with the signal intensity (SI). Thus, changing hematocrit levels may be a confounder in the interpretation of OS-CMR results. We hypothesized that hemodilution confounds the observed signal intensity in OS-CMR images. Venous and arterial blood from five pigs was diluted with lactated Ringer solution in 10 % increments to 50 %. The changes in signal intensity (SI) were compared to changes in blood gases and hemoglobin concentration. We performed an OS-CMR scan in 21 healthy volunteers using vasoactive breathing stimuli at baseline, which was then repeated after rapid infusion of 1 L of lactated Ringer's solution within 5-8 min. Changes of SI were measured and compared between the hydration states. The % change in SI from baseline for arterial (r = -0.67, p < 0.0001) and venous blood (r = -0.55, p = 0.002) were negatively correlated with the changes in hemoglobin (Hb). SI changes in venous blood were also associated with SO2 (r = 0.68, p < 0.0001) and deoxyHb concentration (-0.65, p < 0.0001). In healthy volunteers, rapid infusion resulted in a significant drop in the hemoglobin concentration (142.5 ± 15.2 g/L vs. 128.8 ± 15.2 g/L; p < 0.0001). Baseline myocardial SI increased by 3.0 ± 5.7 % (p = 0.026) following rapid infusion, and in males there was a strong association between the change in hemoglobin concentration and % changes in SI (r = 0.82, p = 0.002). After hyperhydration, the SI response after hyperventilation was attenuated (HV, p = 0.037), as was the maximum SI increase during apnea (p = 0.012). The extent of SI attenuation was correlated with the reduction in hemoglobin concentration at the end of apnea (r = 0.55, p = 0.012) for all subjects and at maximal SI (r = 0.63, p = 0.037) and the end of breath-hold (r = 0.68, p = 0.016) for males only. In dynamic studies using oxygenation-sensitive CMR, the hematocrit level affects baseline signal intensity and the observed signal intensity response. Thus, the hydration status of the patient may be a confounder for OS-CMR image analysis. |
X Demographics
The data shown below were collected from the profiles of 10 X users who shared this research output. Click here to find out more about how the information was compiled.
Geographical breakdown
| Country | Count | As % |
|---|---|---|
| United States | 2 | 20% |
| Canada | 1 | 10% |
| Switzerland | 1 | 10% |
| Saudi Arabia | 1 | 10% |
| Colombia | 1 | 10% |
| United Kingdom | 1 | 10% |
| Unknown | 3 | 30% |
Demographic breakdown
| Type | Count | As % |
|---|---|---|
| Members of the public | 4 | 40% |
| Scientists | 3 | 30% |
| Science communicators (journalists, bloggers, editors) | 2 | 20% |
| Practitioners (doctors, other healthcare professionals) | 1 | 10% |
Mendeley readers
The data shown below were compiled from readership statistics for 29 Mendeley readers of this research output. Click here to see the associated Mendeley record.
Geographical breakdown
| Country | Count | As % |
|---|---|---|
| Unknown | 29 | 100% |
Demographic breakdown
| Readers by professional status | Count | As % |
|---|---|---|
| Researcher | 6 | 21% |
| Student > Master | 5 | 17% |
| Student > Ph. D. Student | 3 | 10% |
| Student > Doctoral Student | 2 | 7% |
| Student > Bachelor | 2 | 7% |
| Other | 4 | 14% |
| Unknown | 7 | 24% |
| Readers by discipline | Count | As % |
|---|---|---|
| Medicine and Dentistry | 12 | 41% |
| Engineering | 3 | 10% |
| Sports and Recreations | 2 | 7% |
| Computer Science | 1 | 3% |
| Psychology | 1 | 3% |
| Other | 3 | 10% |
| Unknown | 7 | 24% |
Attention Score in Context
This research output has an Altmetric Attention Score of 6. This is our high-level measure of the quality and quantity of online attention that it has received. This Attention Score, as well as the ranking and number of research outputs shown below, was calculated when the research output was last mentioned on 19 May 2018.
All research outputs
#6,408,009
of 25,711,518 outputs
Outputs from Critical Reviews in Diagnostic Imaging
#429
of 1,386 outputs
Outputs of similar age
#101,622
of 379,229 outputs
Outputs of similar age from Critical Reviews in Diagnostic Imaging
#10
of 19 outputs
Altmetric has tracked 25,711,518 research outputs across all sources so far. Compared to these this one has done well and is in the 75th percentile: it's in the top 25% of all research outputs ever tracked by Altmetric.
So far Altmetric has tracked 1,386 research outputs from this source. They typically receive a little more attention than average, with a mean Attention Score of 7.1. This one has gotten more attention than average, scoring higher than 68% of its peers.
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We're also able to compare this research output to 19 others from the same source and published within six weeks on either side of this one. This one is in the 47th percentile – i.e., 47% of its contemporaries scored the same or lower than it.