Evidence map›Paper›PMID 41689646›Full record

ArticleEuropean journal of nuclear medicine and molecular imaging2026

Hemoglobin levels and myocardial blood flow in patients undergoing positron emission tomography.

Ahmed Sayed, Mahmoud Al Rifai, Maria Alwan, Ahmad El Yaman, Mouaz Al-Mallah

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Article in European journal of nuclear medicine and molecular imaging, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.

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1 · What the graph read from it

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3 · Its place in the literature

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4 · The record

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5 · Who and what money

Authors and funding

5 authors.

Ahmed SayedHouston Methodist Academic Institute, Weill Cornell Medicine, Houston Methodist DeBakey Heart & Vascular Center, 6550 Fannin Street, Smith Tower - Suite 1801, Houston, TX, 77030, USA.
Mahmoud Al RifaiHouston Methodist Academic Institute, Weill Cornell Medicine, Houston Methodist DeBakey Heart & Vascular Center, 6550 Fannin Street, Smith Tower - Suite 1801, Houston, TX, 77030, USA.
Maria AlwanHouston Methodist Academic Institute, Weill Cornell Medicine, Houston Methodist DeBakey Heart & Vascular Center, 6550 Fannin Street, Smith Tower - Suite 1801, Houston, TX, 77030, USA.
Ahmad El YamanHouston Methodist Academic Institute, Weill Cornell Medicine, Houston Methodist DeBakey Heart & Vascular Center, 6550 Fannin Street, Smith Tower - Suite 1801, Houston, TX, 77030, USA.
Mouaz Al-MallahHouston Methodist Academic Institute, Weill Cornell Medicine, Houston Methodist DeBakey Heart & Vascular Center, 6550 Fannin Street, Smith Tower - Suite 1801, Houston, TX, 77030, USA. mal-mallah@houstonmethodist.org.

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

purposeMyocardial oxygen supply depends on both myocardial blood flow and its oxygen content, as reflected by blood hemoglobin levels. However, there is little data on the impact of hemoglobin levels on myocardial blood flow as captured by positron emission tomography (PET).

methodsConsecutive patients undergoing Rb-82 PET myocardial perfusion imaging (MPI) using regadenoson stress testing and hemoglobin levels available within 90 days of imaging were included. Patients with significant perfusion defects were excluded. Pearson correlation coefficients and multivariable Gamma regression models were used to study the association between myocardial flow reserve (MFR) and hemoglobin levels. The consistency of the prognostic value of MFR across different levels of hemoglobin was assessed using multivariable Andersen-Gill Cox models with robust standard errors.

resultsA total of 2,676 (median age: 67 years; 54.6% females) patients were included. Hemoglobin levels were negatively correlated with rest MBF (-0.33; P < 0.001), positively correlated with stress MBF (0.04; P: 0.04) and positively correlated with MFR (0.38; P < 0.001). In multivariable models, hemoglobin levels were more strongly associated with rest MBF than with stress MBF. The prevalence of microvascular dysfunction (MFR < 2) was significantly less common at higher hemoglobin levels, with an adjusted prevalence of 52.0%, 35.6%%, and 24.6% at hemoglobin levels of 10, 12, and 14 g/dL respectively. MFR was prognostic across the spectrum of hemoglobin, with no statistically significant evidence of an interaction (P for interaction = 0.269).

conclusionHemoglobin levels are negatively associated with rest MBF, weakly positively associated with stress MBF, and positively associated with MFR. The prevalence of microvascular dysfunction, reflected by an MFR < 2, is significantly higher in patients with lower hemoglobin levels. However, the prognostic value of MFR is maintained across the spectrum of hemoglobin levels.

Indexed as

Coronary CirculationHemoglobinsMyocardial Perfusion ImagingPositron-Emission TomographyAgedFemaleHumansMaleMiddle AgedHemoglobinsAnemiaCardiac positron emission tomographyCoronary calciumHemoglobinMyocardial blood flowMyocardial perfusion imagingResting flow

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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.