The Impact of Implementing the Vortex Approach on Airway Management Performance in Stressed Medical Students: A Randomized Controlled Simulation Study.

BACKGROUND The ability to manage airways in emergencies is paramount, especially for less experienced medical students. Although the Vortex Approach, a useful scheme to support decision-making during airway management, promises structured guidance, there's limited research on its benefits among students. Our study aimed to evaluate student proficiency in a simulated difficult airway scenario and assess the advantages of the Vortex Approach. MATERIAL AND METHODS Medical students initially practiced on low-fidelity mannequins. Subsequently, they were divided into Vortex (n=48) and control groups (n=48). The Vortex group received specialized training. Both groups encountered a simulated scenario focusing on proper ventilation and supraglottic device insertion when traditional intubation failed. Performance was assessed using the airway management outcome score (AMOS). RESULTS The Vortex-trained group demonstrated superior capabilities. Fewer participants exceeded 3 lifeline interventions (4.2% vs 16.7%, P=0.046). The Vortex group consistently optimized subsequent attempts (31.3% vs 10.4%, P=0.01) and reduced prolonged apnea episodes (47.9% vs 81.3%, P=0.0009). Their AMOS scores were notably higher (56.3% vs 27.1%, AMOS=2, P=0.002), reflecting better patient outcomes (41.7% vs 10.4%, P=0.0005). CONCLUSIONS There is a marked need to enhance airway management skills among senior medical students. The Vortex Approach, even after brief exposure, yields significant skill improvements, underscoring its potential as a pivotal component in medical training. Integrating it into the curriculum could bridge the evident skill gap, optimizing future patient care.

Identification of risk factors for post-intensive care syndrome in family members (PICS-F) among adult patients: a systematic review.

INTRODUCTION: Relatives of critically ill patients who either die or survive the intensive care unit (ICU) may develop substantial mental health problems that are collectively defined as post-intensive care syndrome in family (PICS-F). MATERIAL AND METHODS: By using a systematised search strategy we included studies that focused on PICS-F in relatives of adult ICU patients and reported the risk factors associated with its development. The search was conducted within PubMed, Embase, SCOPUS, clinicaltrials.gov, and Cochrane Library on the 23 August 2022. PRISMA 2020 guidelines were implemented for appropriate reporting. The objective was to document all possible risk factors associated with the development of PICS-F. RESULTS: We included 51 papers covering 9302 relatives. The frequency of PICS-F varied between 2.5 and 69%. We identified 51 different risk factors of PICS-F, among which we distinguished patient-related ( n = 16), relative-related ( n = 27), and medical staff-related ( n = 8) risk factors. Among 21 studies of the highest quality, we identified the 33 variables associated with the development of PICS-F, of which younger age of a patient, death of a patient, depression in relatives during the ICU stay, history of mental disorders in relatives, being a female relative, being a spouse, and having low satisfaction with communication and care in the ICU were the most commonly reported risk factors. CONCLUSIONS: PICS-F is a highly frequent phenomenon that can be exacerbated by several risk factors. Special attention should be paid to relatives of younger patients with worse prognosis and with the following relative-related risk factors: female sex, being a spouse, and history of mental health disorders. Finally, the medical staff play a role in preventing the PICS-F development, not only by maintenance of proper communication, but also by early identification of relatives prone to PICS-F.

Hybrid planning techniques for early-stage left-sided breast cancer: dose distribution analysis and estimation of projected secondary cancer-relative risk.

PURPOSE: The purpose of this study was to evaluate three techniques of irradiation of left-sided breast cancer patients, three-dimensional conformal radiotherapy (3D-CRT), hybrid Intensity-Modulated Radiotherapy (h-IMRT), and hybrid Volumetric-Modulated Arc Therapy (h-VMAT, h-ARC), in terms of dose distribution in the planning target volume (PTV) and organs at risk (OARs). The second aim was to estimate the projected relative risk of radiation-induced secondary cancers for hybrid techniques. MATERIALS AND METHODS: Three treatment plans were prepared in 3D-CRT, h-IMRT, and h-VMAT techniques for each of the 40 patients, who underwent CT simulation in deep inspiration breath-hold (DIBH). For hybrid techniques, plans were created by combining 3D-CRT and dynamic fields with an 80%/20% dose ratio for 3D-CRT and IMRT or VMAT. Cumulative dose-volume histograms were used to compare dose distributions within the PTV and OARs (heart, left anterior descending coronary artery [LAD], left and right lung [LL, RL], right breast [RB]). Projected risk ratios for secondary cancers were estimated relative to 3D-CRT using the organ equivalent dose (OED) concept for the Schneider's linear exponential, plateau, and full mechanistic dose-response model. RESULTS: All plans fulfilled the PTV criterium: V95%≥95%. Compared to 3D-CRT, both hybrid techniques showed significantly better target coverage (PTV: V95%>98%, p < 0.001), and the best conformality was achieved by h-ARC plans (CI: 1.18 ± 0.09, p < 0.001). Compared to 3D-CRT and h-ARC, h-IMRT increased the average sum of monitor units (MU) over 129.9% (p < 0.001). H-ARC increased the mean dose of contralateral organs and the LL V5Gy parameter (p < 0.001). Both hybrid techniques significantly reduced the Dmax of the heart by 5 Gy. Compared to h-IMRT, h-ARC increased secondary cancer projected relative risk ratios for LL, RL, and RB by 18, 152, and 81%, respectively. CONCLUSIONS: The results confirmed that both hybrid techniques provide better target quality and OARs sparing than 3D-CRT. Hybrid VMAT delivers less MU compared to hybrid IMRT but may increase the risk of radiation-induced secondary malignancies.

Intraoperative Hypotension and Its Association with Postoperative Acute Kidney Injury in Patients Undergoing Pancreaticoduodenectomy: A 5-Year, Single-Center, Retrospective Cohort Study.

BACKGROUND Intraoperative hypotension (IOH) is a common phenomenon in high-risk surgery and is often linked to postoperative acute kidney injury (AKI). Pancreaticoduodenectomy (PD), or Whipple's procedure, is a lengthy and complex surgical procedure to remove the head of the pancreas, gallbladder and bile duct, and the first part of the duodenum. This retrospective 5-year study from a single center in Poland included 303 patients who underwent PD and evaluated IOH as a factor associated with AKI. MATERIAL AND METHODS We analyzed perioperative data to assess how various IOH thresholds can predict AKI (according to KDIGO criteria). Several IOH definitions were applied, including absolute and relative thresholds, based on the mean arterial pressure (MAP). Statistically significant IOH thresholds were inserted into multivariable logistic regression models with previously established independent variables. RESULTS We included 303 patients over a 5-year period (2016-2021). There were 58 (19.1%) cases of postoperative AKI. MAP <55 mmHg and a maximal% drop from preinduction MAP were the only IOH definitions associated with AKI. Multivariable analysis revealed that max% drop from preinduction MAP (per 10%, OR=1.65; AUROC=0.70) was the IOH definition best suited for AKI prediction in patients undergoing PD. CONCLUSIONS In patients undergoing PD, it is important to prevent excessive blood pressure drops in regards to preinduction blood pressure values. In this cohort, relative IOH thresholds were better suited for prediction of AKI than the absolute IOH thresholds.

Comparison of Postoperative Outcomes of Hand-Sewn Versus Stapled Esophago-jejunal Anastomosis During Total Gastrectomy for Gastric Cancer in 72 Patients: A Retrospective, Single-Center Study in Poland.

BACKGROUND Mechanical stapling is a commonly used alternative to hand-sewn technique for esophago-jejunal anastomosis in total gastrectomy (TG). Some studies report reduction in postoperative complications in the stapler group. This retrospective study aimed to compare short- and long-term surgical outcomes between the groups with stapled and hand-sewn esophago-jejunal anastomosis (EJA) during open TG for gastric cancer. MATERIAL AND METHODS The study included 72 adult patients with gastric cancer who underwent TG in the Department of Digestive Tract Surgery in Katowice between May 2018 and December 2021. The patients were divided into 2 groups according to the technique of EJA: stapled (44 cases) or hand-sewn (28 cases). We compared the groups in terms of the duration of the surgery, length of hospital stay, and occurrence of complications (focusing on anastomotic leakage, stricture and abdominal abscess). RESULTS There were no significant differences in duration of the surgery (P=0.6), blood loss (P=0.7), or length of postoperative hospital stay (P=0.2) among the groups. Early postoperative complications rates were 9.1% (4/44) in the stapler group and 17.9% (5/28) in the hand-sewn group (P=0.27). The most frequent complication was anastomotic leakage, with 2 cases in each group (P=0.76). The mean follow-up time was 1.8±0.9 (0.3-3.6) years. During this period the anastomotic stricture occurred in 7 (15.9%) cases with stapled anastomosis and in 5 (17.9%) cases with hand-sewn anastomosis (P=0.52). CONCLUSIONS In this study there were no significant differences in mortality, morbidity, and surgery duration between stapled and hand-sewn esophago-jejunal anastomosis in total gastrectomy.

Three-dimensional conformal radiotherapy (3D-CRT) vs. volumetric modulated arc therapy (VMAT) in deep inspiration breath-hold (DIBH) technique in left-sided breast cancer patients-comparative analysis of dose distribution and estimation of projected secondary cancer risk.

PURPOSE: The purpose of this study was to compare two techniques of irradiation of left-sided breast cancer patients who underwent breast-conserving surgery, three-dimensional conformal radiotherapy technique (3D-CRT) and volumetric modulated arc therapy (VMAT), in terms of dose distribution in the planning target volume (PTV) and organs at risk (OARs). The second aim of the study was estimation of the projected risk of radiation-induced secondary cancer for both radiotherapy techniques. MATERIALS AND METHODS: For 25 patients who underwent CT simulation in deep inspiration breath-hold (DIBH), three treatment plans were generated: one using a three-dimensional conformal radiotherapy technique and two using volumetric modulated arc therapy. First VMAT-DIBH geometry consisted of three partial arcs (ARC-DIBH 3A) and second consisted of four partial arcs (ARC-DIBH 4A). Cumulative dose-volume histograms (DVHs) were used to compare dose distributions within the PTV and OARs (heart, left anterior descending coronary artery [LAD], ipsilateral and contralateral lung [IL, CL], and contralateral breast [CB]). Normal tissue complication probabilities (NTCPs) and organ equivalent doses (OEDs) were calculated using the differential DVHs. Excess absolute risks (EARs) for second cancers were estimated using Schneider's full mechanistic dose-response model. RESULTS: All plans fulfilled the criterium for PTV V95% ≥ 95%. The PTV coverage, homogeneity, and conformity indices were significantly better for VMAT-DIBH. VMAT showed a significantly increased mean dose and V5Gy for all OARs, but reduced LAD Dmax by 15 Gy. For IL, CL, and CB, the 3D-CRT DIBH method achieved the lowest values of EAR: 28.38 per 10,000 PYs, 2.55 per 10,000 PYs, and 4.48 per 10,000 PYs (p < 0.001), compared to 40.29 per 10,000 PYs, 15.62 per 10,000 PYs, and 23.44 per 10,000 PYs for ARC-DIBH 3A plans and 41.12 per 10,000 PYs, 15.59 per 10,000 PYs, and 22.73 per 10,000 PYs for ARC-DIBH 4A plans. Both techniques provided negligibly low NTCPs for all OARs. CONCLUSION: The study shows that VMAT-DIBH provides better OAR sparing against high doses. However, the large low-dose-bath (≤ 5 Gy) is still a concern due to the fact that a larger volume of normal tissues exposed to lower doses may increase a radiation-induced risk of secondary cancer.

The role of uropathogenic Escherichia coli adhesive molecules in inflammatory response- comparative study on immunocompetent hosts and kidney recipients.

BACKGROUND: Urinary tract infections (UTI) represent one of the most common contagious diseases in humans. Uropathogenic Escherichia coli (UPEC) strains are recognized as the most frequent causative agent, and these express a range of virulence factors including the adhesins. Immune response to UPEC under immunosuppression has not been fully understood yet. Interleukin 1ß (IL1ß), 6 (IL6) and 17 (IL17) represent clinically relevant markers of inflammation. AIM: The study aimed to investigate the interplay between UPEC genotype and hosts' immune status in shaping local inflammatory response in the course of an UTI episode. The respective numbers of: 18 kidney recipients with UPEC UTI, 28 immunocompetent hosts with UPEC UTI and 29 healthy controls were involved. Urine IL1ß, IL6, and IL17/creatinine ratios in relation to fimH, csgA, papC, tosA, and flu genes presence in UPEC isolated from the urine samples were analyzed. Apart from traditional statistics, also machine learning algorithms were applied. RESULTS: The urine levels of IL1ß and IL 6 were similar in kidney recipients and the immunocompetent hosts. IL1ß levels were higher in both kidney recipients and immunocompetent hosts than in controls, while IL6 levels were higher only in immunocompetent hosts than in controls. In the machine learning classification model, high urine IL17 levels were significantly more prevalent in controls, while low IL17 levels in urines infected with Ag43-positive UPEC strains, regardless of the host's immune status. In the traditional statistical analysis, IL17 levels appeared significantly higher in urine samples from kidney recipients infected with Ag43-negative UPEC strains. CONCLUSIONS: In the UTI- affected patients, the combination of the immune status of an individual and Ag43 status of the UPEC strain determined urine IL17 level in the analyzed group. However, IL17 levels above median were overall more prevalent in controls.

A rare case of giant teratocarcinoma of the testis with accumulation of fluid.

Testicular cancer is one of the most curable cancers. However, the course of the disease largely depends on the clinical stage at diagnosis, and there are still cases where the tumor size is large, which makes surgical treatment challenging. A 30-year-old man presented with painless, extremely enlarged scrotum. A CT scan revealed a tumor of the right testis of 21.5 × 15 × 18cm in size. The patient underwent a right orchiectomy and histologic examination revealed teratocarcinoma. Suspicion of hydrocele testis should prompt meticulous differential diagnosis including malignancies. There is a strong need to increase public awareness in terms of symptoms of testicular cancer.

Functional nuclear retention of pre-mRNA involving Cajal bodies during meiotic prophase in European larch (Larix decidua).

Gene regulation ensures that the appropriate genes are expressed at the proper time. Nuclear retention of incompletely spliced or mature mRNAs is emerging as a novel, previously underappreciated layer of posttranscriptional regulation. Studies on this phenomenon indicated that it exerts a significant influence on the regulation of gene expression by regulating export and translation delay, which allows the synthesis of specific proteins in response to a stimulus or at strictly controlled time points, for example, during cell differentiation or development. Here, we show that transcription in microsporocytes of European larch (Larix decidua) occurs in a pulsatile manner during prophase of the first meiotic division. Transcriptional activity was then silenced after each pulse. However, the transcripts synthesized were not exported immediately to the cytoplasm but were retained in the nucleoplasm and Cajal bodies (CBs). In contrast to the nucleoplasm, we did not detect mature transcripts in CBs, which only stored nonfully spliced transcripts with retained introns. Notably, the retained introns were spliced at precisely defined times, and fully mature mRNAs were released into the cytoplasm for translation. As similar processes have been observed during spermatogenesis in animals, our results illustrate an evolutionarily conserved mechanism of gene expression regulation during generative cells development in Eukaryota.

Retrospective Study of Surgical Outcomes in 60 Patients with Crohn Disease from a Single Center in Poland.

BACKGROUND In Crohn disease (CD), pharmacotherapy with nutritional support is the treatment of choice. However, complications and a lack of response to drugs are indications for surgery. The aim of this study was to present indications for surgery and methods of surgical treatment of CD and to analyze the postoperative morbidity and mortality risk factors. MATERIAL AND METHODS This was a retrospective analysis of adult patients who underwent surgery for CD between January 2015 and January 2019. Sixty of 457 patients (13%) hospitalized for CD required surgical treatment. The parameters age, sex, body mass index, duration, behavior and location of the disease, pharmacotherapy, indications for surgery, type and duration of surgery, perioperative complications, and laboratory tests results were analyzed. RESULTS Most procedures (90%) were elective. The most common indications for surgery were fistulae and strictures. The most frequently performed procedure was right hemicolectomy (60%). Thirty-two percent of patients had postoperative complications. Perianal disease (P=0.002) and penetrating behavior (P=0.01) were associated with more surgeries. Stricturing and penetrating behavior was more frequent in patients with ileal/ileocecal involvement than in those with CD affecting the colon (P=0.039). Patients with smoking history had a significantly lower age at first surgery (P=0.02). The use of anti-TNF medications appeared to extend time between diagnosis and first surgery (P=0.014). CONCLUSIONS Although the analysis did not reveal any risk factors for perioperative complications, perianal manifestations, penetrating disease type, ileal/ileocecal involvement, and smoking may be associated with risk of earlier surgery or multiple surgeries.

Structural and Charge Transport Properties of Composites of Phosphate-Silicate Protonic Glass with Uranyl Hydroxy-Phosphate and Hydroxy-Arsenate Obtained by Mechano-Chemical Synthesis Undergoing Hydration Changes.

The introduction of the hydrogen economy, despite its obvious technological problems, creates a need for a significant number of niche-focused solutions, such as small-sized (10-100 W) fuel cells able to run on hydrogen of lesser purity than what is considered a standard in the case of PEMFCs. One of the solutions can be derived from the fact that an increase in the operational temperature of a cell significantly decreases its susceptibility to catalyst poisoning. Electrolytes suitable for the so-called medium temperature operational range of 120-400 °C, hence developed, are neither commercialized nor standardized. Among them, phosphate silicate protonically conductive glasses were found not only to reveal interestingly high levels of operational parameters, but also, to exhibit superior chemical and electrochemical stability over their polymeric counterparts. On the other hand, their mechanical properties, including cracking fragility, still need elaboration. Initial studies of the composite phosphate silicate glasses with uranyl-based protonic conductors, presented here, proved their value both in terms of application in fuel cell systems, and in terms of understanding the mechanism governing the charge transport mechanism in these and similar systems. It was found that whereas systems containing 10-20 wt% of the crystalline additive suffer from significant instability, materials containing 45-80 wt% (with an optimum at 60%) should be examined more thoughtfully. Moreover, the uranyl hydrogen phosphate was found to surpass its arsenate counterpart as an interesting self-healing behavior of the phase structure of the derived composite was proved.

Different Patterns of mRNA Nuclear Retention during Meiotic Prophase in Larch Microsporocytes.

Recent studies show a crucial role of post-transcriptional processes in the regulation of gene expression. Our research has shown that mRNA retention in the nucleus plays a significant role in such regulation. We studied larch microsporocytes during meiotic prophase, characterized by pulsatile transcriptional activity. After each pulse, the transcriptional activity is silenced, but the transcripts synthesized at this time are not exported immediately to the cytoplasm but are retained in the cell nucleus and especially in Cajal bodies, where non-fully-spliced transcripts with retained introns are accumulated. Analysis of the transcriptome of these cells and detailed analysis of the nuclear retention and transport dynamics of several mRNAs revealed two main patterns of nuclear accumulation and transport. The majority of studied transcripts followed the first one, consisting of a more extended retention period and slow release to the cytoplasm. We have shown this in detail for the pre-mRNA and mRNA encoding RNA pol II subunit 10. In this pre-mRNA, a second (retained) intron is posttranscriptionally spliced at a precisely defined time. Fully mature mRNA is then released into the cytoplasm, where the RNA pol II complexes are produced. These proteins are necessary for transcription in the next pulse to occur.mRNAs encoding translation factors and SERRATE followed the second pattern, in which the retention period was shorter and transcripts were rapidly transferred to the cytoplasm. The presence of such a mechanism in various cell types from a diverse range of organisms suggests that it is an evolutionarily conserved mechanism of gene regulation.

The rationale for selenium supplementation in patients with autoimmune thyroiditis, according to the current state of knowledge.

Selenium (Se) supplements are commonly prescribed to autoimmune thyroiditis (AIT) patients by European endocrinologists, despite the lack of official guidelines. The majority of Europe is depleted of natural Se sources, and the daily population intake does not comply with recommended values. Optimal individual plasma Se concentration is reached when the selenoproteins (selenoprotein P, glutathione peroxidase) are fully saturated. However, Se intake has to be regulated because both Se shortage and overdose negatively impact health. In the case of AIT, Se may alleviate symptoms or prevent progression to hypothyroidism and postpartum hypothyroidism. Se supplementation in euthyroid, subclinical, or overt hypothyroid AIT patients decreased thyroid autoantibodies, lowered or maintained the TSH level, decreased the fT4/fT3 ratio, reduced the body's oxidative stress and inflammatory status, and amended quality of life and thyroid ultrasound structure and volume. In pregnant females, adequate Se intake protected them against miscarriages, preeclampsia/hypertension, preterm birth, small-for-gestational-age infants' birth, and improved child's neuropsychological development. In the elderly population, adequate Se supplementation decreased cardiovascular diseases and hypertension risk, but prolonged intake of excessive doses increased the all-cause mortality rate. Routine Se supplementation implementation requires from researchers and clinicians consideration of specific populational differences in natural Se and iodine supply, the patient's clinical situation (supplementation simultaneously or before levothyroxine treatment, AIT/non-AIT hypothyroidism), individual response to supplementation (Se and selenoprotein P assessment), predisposition (genetic testing), the status of other trace elements, and the interplay between those micronutrients. Moreover, the safety of commercially available Se formulations, doses, and duration of treatment should be determined. Proper guidelines are warranted to standardise the medical approach to Se supplementation. This article presents a comprehensive review of recent randomised-controlled trials, meta-analyses, and clinical trials concerning the risks and benefits of Se supplementation in different clinical settings and specific populations with particular emphasis on AIT in a practical manner.

The Multispecies Probiotic Effectively Reduces Homocysteine Concentration in Obese Women: A Randomized Double-Blind Placebo-Controlled Study.

Dysregulated metabolism of homocysteine (Hcy) is associated with obesity. Supplementation with probiotics can potentially be a natural therapeutic method for metabolic disorders. The precise mechanism in which microbiota affect Hcy metabolism in obese individuals is still unknown. The aim of this study was to evaluate the effects of a 12-week supplementation with a multispecies probiotic on Hcy levels, oxidative stress, inflammation and lipid profile in obese patients. This randomized double-blind placebo-controlled trial was performed on 50 obese women (aged 45-70 years). Subjects were randomly assigned to take either a multispecies probiotic supplement (n = 25) or placebo (n = 25) for 12 weeks. The probiotic contained nine bacterial strains containing 2.5 × 109 CFU/g. Biochemical and anthropometric measurements were carried out at baseline and after 12 weeks of intervention. At the end of the study, a significant decrease in Hcy, tumor necrosis factor α (TNF-α), total cholesterol (TC), low-density lipoprotein cholesterol (LDL) and triglyceride (TG) levels were observed in the probiotic group. The amelioration of total antioxidant status (TAS) was also observed. The 12-week supplementation of the multispecies probiotic (Ecologic® BARIER) effectively reduced Hcy concentration, oxidative stress and inflammation, and improved the lipid profile. These multidirectional effects can potentially reduce cardiometabolic risks.

15O-H2O PET/CT as a tool for the quantitative assessment of early post-radiotherapy changes of heart perfusion in breast carcinoma patients.

OBJECTIVE: Studies examining radiation-induced heart toxicity in breast cancer patients are inconclusive. The aim of this study was to prospectively and quantitatively asses myocardial blood flow (MBF) with, for the first time, 15O-H2O PET/CT as a marker of heart damage in irradiated breast cancer patients. METHODS: 15 breast cancer patients receiving intact breast or chest wall irradiation were included in the analysis (six with right-sided and nine with left-sided breast cancer). They underwent 15O-H2O PET/CT before radiotherapy (RT) and 2 and 8 months after RT. MBF was quantitatively assessed at rest and under stress conditions in 17 heart segments distinguished according to the American Ultrasound Association classification. Regional MBF values were derived in each of the coronary artery territories. RESULTS: MBF decreased in 53% and increased in 33% of cases 2 months after RT in both left-sided and right-sided breast cancer patients. Stress testing was more sensitive than at-rest testing, demonstrating decreased perfusion in the segments supplied by the left anterior descending coronary artery (LAD) [5.41 ± 1.74 vs 4.52 ± 1.82 ml (g*min)-1; p = 0.018], which persisted at 6 months [5.41 ± 1.74 vs 4.40 ± 1.38 ml (g*min)-1; p = 0.032] and a decrease in global heart perfusion [5.14 ± 1.49 vs 4.46 ± 1.73 ml (g*min)-1; p = 0.036]. A minimal radiation dose applied to the LAD correlated with MBF changes observed 2 months after RT (r = -0.57; p = 0.032). Radiological findings were not correlated with clinical symptoms of heart toxicity. CONCLUSION: 15O-H2O PET/CT is safe and effective for the early detection and quantitative analysis of subclinical post-RT changes in heart perfusion in breast cancer patients. The LV segments supplied by the LAD are the main site of MBF changes. A minimum radiation dose deposited in the LAD may be a predictor of radiation-induced heart toxicity. Advances in knowledge: This is the first time that 15O-H2O PET/CT has been used to assess MBF after RT and the first granular description of the distribution of blood flow changes after breast cancer RT.