Mild Ischemia Research Articles

Impact of fractional flow reserve measurement on angina frequency in the invasive arm of the ISCHEMIA trial

Abstract Introduction Fractional flow reserve (FFR) is an invasive, lesion-specific surrogate for myocardial ischemia. The use of FFR to guide lesion selection for revascularization is believed to improve outcomes compared to an angiographic approach because it allows categorization of lesions based on hemodynamic significance. Lesions that are not hemodynamically significant can be safely deferred while the revascularization of significant lesions has been reported to improve quality of life compared to medical therapy alone. Purpose To compare the outcomes of patients randomized to the invasive (INV) arm of the ISCHEMIA trial who underwent FFR during initial angiography with those whose treatment was guided by angiography alone. Methods The ISCHEMIA data set was obtained from the National Heart, Lung, and Blood Institute under a data use agreement. Subjects randomized to the INV arm who underwent FFR were compared to those who underwent angiography alone. Categorial variables were compared using the chi-squared or Fisher’s exact test. Continuous variables were compared using the student T-test or Wilcoxon rank sum test. Multivariable linear mixed effects regression was used to evaluate the association of FFR use on SAQ7 AF score as well as assess changes across five years of follow-up. Covariates included in the model were based on their univariate and clinical significance. All tests were two-sided and P<0.05 was considered statistically significant. Results Of the 5,179 patients with chronic coronary syndromes and at least moderate ischemia on stress testing, 2588 were assigned to the INV strategy and 2210 had data available for analysis. Of these individuals, 410 (19%) had FFR performed during their diagnostic angiogram. Females comprised 24% of FFR patients and 24% of non-FFR patients (P=0.85). FFR patients were older than non-FFR patients (65.7 [8.7] years vs. 64.3 [9.6] years, P=0.006). The incidence of hypertension, diabetes, smoking, or prior MI at baseline did not differ between groups. Mean ejection fraction did not differ between groups. Fewer FFR patients had severe ischemia at baseline (45% vs. 52%) and more had mild or moderate ischemia (54% vs. 48%) (P=0.009). FFR patients had fewer native vessels with >70% stenosis than non-FFR patients (1.0[0.9] vs. 1.5[1.0], P<0.001), and less complex disease as assessed by the Duke jeopardy score (P<0.001). On multivariable linear mixed effects regression, FFR was not associated with a significant change in the SAQ AF score (0.56 (-0.85 – 1.97; P=0.44)), after adjusting for other covariates. However, the SAQ7 AF score was 0.22 units less in those that underwent FFR compared to those that did not (95%CI=-0.44 – -0.01; P=0.043) when assessed over follow-up time. Conclusion ISCHEMIA patients randomized to an INV strategy who underwent physiologic assessment with FFR had no improvement in angina frequency compared to those who underwent angiography alone.

Mild and advanced liver ischemia differentially affect the cellular acyl-CoA metabolome

Mild and advanced liver ischemia differentially affect the cellular acyl-CoA metabolome

Reduced Muscle Mass and Muscle Quality in Patients with Intermittent Claudication due to Peripheral Artery Disease

ObjectivePeripheral arterial disease (PAD) is associated with reduced muscle mass and quality, but the effects of leg ischemia caused by PAD on muscle quality remain poorly understood. The purpose of this study was to evaluate leg muscle mass and muscle quality in patients with intermittent claudication due to PAD using bioelectrical impedance analysis (BIA). MethodsOne hundred forty-one patients with intermittent claudication due to PAD who visited Tokyo Medical University Hospital from April 2019 to April 2020 were retrospectively analyzed. Leg ischemia was assessed using ankle-brachial index (ABI). The skeletal muscle mass (SMM) assessed leg muscle mass, while the phase angle (PhA) assessed leg muscle quality using BIA. ResultsA total of 282 legs in 141 patients were included in the analysis. Leg PhA and SMM showed a decreasing trend according to the severity of leg ischemia (borderline/no ischemia: 2.80 ± 0.50 kg/m2, 4.38 ± 0.94°; mild ischemia: 2.83 ± 0.49 kg/m2, 4.33 ± 1.03°; moderate/severe ischemia: 2.50 ± 0.40 kg/m2, 3.89 ± 0. 88°; p<0.001 and p=0.020, respectively). The ABI was moderately correlated with leg SMM (B=0.347, β=0.134, p<0.001) and leg PhA (B=0.577, β=0.111, p=0.013) after adjustment for all significant covariates. Leg PhA was moderately correlated with leg SMM (r = 0.318, p < 0.001). ConclusionsLeg ischemia, especially when moderate or severe, has an adverse effect on both muscle mass and quality in the lower extremities and is associated with skeletal muscle myopathy.

Left ventricular shape index and eccentricity index with ECG-gated Nitrogen-13 ammonia PET/CT in patients with myocardial infarction, ischemia, and normal perfusion

BackgroundLV geometry with shape index (SI) and eccentricity index (EI) measured by myocardial perfusion positron emission tomography/computed tomography (PET/CT) may allow the evaluation of left ventricular (LV) adverse remodeling. This first study aims to explore the relationship of SI and EI values acquired by Nitrogen-13 ammonia PET/CT in patients with normal perfusion, ischemia, and myocardial infarction. And evaluate the correlations between the variables of LV geometry, and with the variables of LV function. Methods and resultsOne hundred and forty patients who underwent an electrocardiogram (ECG)-gated PET/CT were selected and classified into 4 groups according to ischemia or infarction burden (normal perfusion, mild ischemia, moderate-severe ischemia, and infarction). The variables were automatically retrieved using dedicated software (QPS/QGS; Cedars-Sinai, Los Angeles, CA, USA). On multicomparison analysis (one-way ANOVA and Dunnett's Test), subjects in the infarction group had significant higher values of SI end-diastolic rest (P < 0.001), and stress (P = 0.003), SI end-systolic rest (P = 0.002) and stress (P < 0.001) as well as statistically significant lower values of EI rest (P < 0.001) and stress (P < 0.001) when compared with all other groups. Regarding Pearson correlation, in the infarcted group all the variables of SI and EI were significantly correlated (P < 0.001) with strong correlation coefficients (>0.60). SI end-systolic correlated significantly with the variables of LV function independently of the group of patients (P < 0.05). ConclusionsShape and eccentricity indices differ in patients with myocardial infarction as compared to patients with ischemia or normal perfusion. This encourage further research in their potential for detecting LV adverse remodeling.

Acyl-coenzyme A species in mild and advanced liver ischemia determined by HPLC, LC-MC/MS, NMR, and photo-/fluorimetric assays

Acyl-coenzyme A species in mild and advanced liver ischemia determined by HPLC, LC-MC/MS, NMR, and photo-/fluorimetric assays

Prognostic value of the left ventricular ejection fraction reserve acquired by gated myocardial perfusion SPECT in patients with CAD and reduced stress LVEF.

Left ventricular ejection fraction (LVEF) strongly predicts cardiac events. However, conflicting findings exist regarding the prognostic value of the LVEF reserve (ΔLVEF) when measured by gated single-photon emission computed tomography myocardial perfusion imaging (SPECT G-MPI). In particular, data related to the prognostic value of ΔLVEF when measured by SPECT in patients with reduced LVEF are scarce. In this study, we aimed to evaluate the prognostic value of ΔLVEF when acquired by SPECT G-MPI in patients with coronary artery disease (CAD) and a LVEFStress < 60%. We retrospectively recruited 260 consecutive patients diagnosed with CAD by coronary angiography (CAG) and a LVEFStress < 60%, as determined by SPECT G-MPI. These patients were followed up for 33.4 ± 7.6 months. The patients were divided into two groups (ΔLVEF > 0% and ΔLVEF ≤ 0%), and survival analyses were conducted. The primary endpoints were major adverse cardiac events (MACEs), a composite of all-cause death, nonfatal myocardial infarction, unplanned coronary revascularization, and hospitalization for unstable angina. We observed 69 MACEs (26.5%). The cumulative incidence of MACEs in patients with ΔLVEF ≤ 0% was significantly higher than in patients with ΔLVEF > 0% (P = 0.042). Multivariate Cox regression further revealed that a ΔLVEF ≤ 0% represented an independent predictor of MACEs (adjusted hazard ratio [HR]: 1.276; 95% confidence interval [CI]: (1.006, 1.618), P = 0.045). Adding a ΔLVEF ≤ 0% to traditional myocardial perfusion and function variables evaluated by MPI significantly improved the ability to predict MACEs (P = 0.044). Determining ΔLVEF by SPECT G-MPI was associated with MACEs and improved risk stratification compared to prediction models based on traditional perfusion and functional parameters in CAD patients with left ventricular dysfunction, particularly those with no or mild myocardial ischemia.

Gasless endoscopic transaxillary subcutaneous mastectomy and immediate reconstruction with implants (GETSMIRI) for breast cancer: Lei's five-step method

BackgroundEndoscopic nipple-sparing mastectomy (E-NSM) is a promising procedure in the treatment of breast cancer, but the limitations of endoscopic tools and intrinsic technical complexity of the technique hinder its applicability. Here, we introduce a novel surgery, gasless endoscopic transaxillary subcutaneous mastectomy and immediate reconstruction with implants (GETSMIRI), for breast cancer. and early effects. MethodsA retrospective analysis of the clinical data of 11 female patients, aged 50 (27–78) years, admitted to our hospital from January to December 2022, who underwent gasless endoscopic transaxillary subcutaneous mastectomy and immediate reconstruction with implants (GETSMIRI), was conducted. This study was designed to assess patient satisfaction before and after breast reconstruction, early complications, and breast function. ResultsThe tumors were all solitary, with a mean maximum diameter of 1.0 (0–2.0) cm and a mean distance of 2.3 (2–4) cm from the nipple, the mean intraoperative bleeding volume was 47.5 mL, and the mean hospital stay was 1.5 d. Postoperatively, 1 patient developed depigmentation of the nipple due to mild ischemia. There were no incisional complications, subcutaneous emphysema, infection, areola necrosis, skin flap necrosis, or removal of the prosthesis and/or patch. No tumor recurrence or metastasis was observed during the follow-up period. The difference between breast satisfaction and psychosocial health scores was not statistically significant (P = 0.680; P = 0.612). ConclusionGETSMIRI, immediate implantable breast reconstruction, is less invasive than other such procedures, and short-term follow-up results show good postoperative satisfaction, making it an alternative surgical method.

Relation between high-sensitivity troponin I serum levels and myocardial ischemia in patients with suspected chronic coronary syndrome: The RESET-MI study

BackgroundPrevious studies showed that exercise may increase cardiac troponin serum levels; whether the occurrence of myocardial ischemia influences the changes of exercise-induced troponin raise, however, remains debatable. MethodsWe prospectively enrolled consecutive patients undergoing for the first time an elective stress myocardial perfusion scintigraphy (MPS) because of clinical suspicion of obstructive coronary artery disease (CAD). Patients were divided into 3 groups based on the evidence and degree of stress-induced myocardial ischemia at MPS: 1) group 1, no myocardial ischemia (≤4 %); 2) group 2, mild myocardial ischemia (5–10 %); 3) group 3, moderate-to-severe myocardial ischemia (≥10 %). High-sensitivity cardiac troponin I (cTnI) was measured immediately before (T0) and 1 hour (T1) and 4 h (T2) after the stress test. ResultsOne hundred-seven patients (71 males; age 65.6 ± 9.4 years) were enrolled in the study. Serum hs-cTnI concentrations (logarithmic values) significantly increased after MPS, compared to baseline, in the whole population, from 1.47±1.26 ng/L at T0, to 1.68±1.12 ng/L at T1 (p<0.001) and 2.15±1.02 ng/L at T2 (p<0.001 vs. both T0 and T1). The increase in hs-cTnI did not significantly differ between the 3 groups (p = 0.44). The heart rate achieved during the test was the strongest determinant of cTnI increase (p < 0.001) after the stress test. ConclusionsIn patients with suspected CAD, stress MPS induces an increase of cTnI that is independent of the induction and extension/severity of myocardial ischemia and is mainly related to myocardial work, as indicated by the heart rate achieved during the test.

Relation between high-sensitivity troponin i serum levels and myocardial ischemia in patients with suspected chronic coronary syndrome: the RESET-MI study

Abstract Background Previous studies showed that exercise may increase cardiac troponin serum levels; however, whether exercise-induced myocardial ischemia influences the exercise-induced increase of troponin levels remains debatable. Methods We prospectively enrolled consecutive patients undergoing an elective stress myocardial perfusion scintigraphy (MPS) because of a clinical suspicion of obstructive coronary artery disease (CAD). Patients were divided into 3 groups according to the evidence and degree of stress-induced myocardial ischemia at MPS: 1) Group 1, no ischemia (≤4% of myocardium); 2) Group 2, mild ischemia (5-10%); 3) Group 3, moderate-to-severe myocardial ischemia (≥10%). High-sensitivity cardiac troponin I (cTnI) was measured immediately before (T0) and 1 hour (T1) and 4 hours (T2) after the stress test. A successive evaluation of patients was performed at 24 months. Results One-hundred consecutive patients (64 males; age 65.5±9.5 years) were enrolled in the study. An exercise stress test and a dipyridamole stress test were performed in 81 and 19 patients, respectively. Serum hs-cTnI concentrations significantly increased after stress test, compared to baseline, in the whole population, from (median, interquartile range) 3.9 (2.5-6.1) ng/L at T0, to 4.2 (2.8-7.3) ng/L at T1 (p&amp;lt;0.001) and 6.7 (3.8-14.1) ng/L at T2 (p&amp;lt;0.001 vs. both T0 and T1). The increase in hs-cTnI did not significantly differ between the 3 groups (p=0.35; Figure). The increase was significant after both exercise (+54.5%) and dipyridamole (+18.2%), although the increase was greater after exercise (p=0.002). Heart rate achieved during the test was the strongest determinant of cTnI increase after the stress test (p &amp;lt; 0.001). Conclusions In patients with suspected CAD, stress MPS induces an increase of cTnI that is independent of the induction and severity of myocardial ischemia and is mainly related to myocardial work, as indicated by heart rate achieved during the stress test.Figure

11 Differences in neuronal death, reactive astrogliosis, and BBB leakage between gerbil striata following mild and severe transient forebrain ischemia

11 Differences in neuronal death, reactive astrogliosis, and BBB leakage between gerbil striata following mild and severe transient forebrain ischemia

Multi-Method Quantification of Acetyl-Coenzyme A and Further Acyl-Coenzyme A Species in Normal and Ischemic Rat Liver.

Thioesters of coenzyme A (CoA) carrying different acyl chains (acyl-CoAs) are central intermediates of many metabolic pathways and donor molecules for protein lysine acylation. Acyl-CoA species largely differ in terms of cellular concentrations and physico-chemical properties, rendering their analysis challenging. Here, we compare several approaches to quantify cellular acyl-CoA concentrations in normal and ischemic rat liver, using HPLC and LC-MS/MS for multi-acyl-CoA analysis, as well as NMR, fluorimetric and spectrophotometric techniques for the quantification of acetyl-CoAs. In particular, we describe a simple LC-MS/MS protocol that is suitable for the relative quantification of short and medium-chain acyl-CoA species. We show that ischemia induces specific changes in the short-chain acyl-CoA relative concentrations, while mild ischemia (1-2 min), although reducing succinyl-CoA, has little effects on acetyl-CoA, and even increases some acyl-CoA species upstream of the tricarboxylic acid cycle. In contrast, advanced ischemia (5-6 min) also reduces acetyl-CoA levels. Our approach provides the keys to accessing the acyl-CoA metabolome for a more in-depth analysis of metabolism, protein acylation and epigenetics.

Risk factors for difficult endoscopic hemostasis for colonic diverticular bleeding and efficacy and safety of transcatheter arterial embolization.

This study aimed to investigate the risk factors for difficult endoscopic hemostasis in patients with colonic diverticular bleeding and to evaluate the efficacy and safety of transcatheter arterial embolization (TAE) for colonic diverticular bleeding. This study included 208 patients with colorectal diverticular hemorrhage. The non-interventional radiotherapy group consisted of patients who underwent successful spontaneous hemostasis (n = 131) or endoscopic hemostasis (n = 56), whereas the interventional radiotherapy group consisted of patients who underwent TAE (n = 21). Patient clinical characteristics were compared to identify independent risk factors for the interventional radiotherapy group. Furthermore, the hemostasis success rate, rebleeding rate, complications, and recurrence-free survival were compared between patients who underwent endoscopic hemostasis and those who underwent TAE. Bleeding from the right colon (odds ratio [OR]: 7.86; 95% confidence interval [CI]: 1.6-38.8; P = .0113) and systolic blood pressure <80 mm Hg (OR: 0.108; 95% CI: 0.0189-0.62; P = .0126) were identified as independent risk factors for the interventional radiology group. The hemostasis success rate (P = 1.00), early rebleeding rate (within 30 days) (P = .736), late rebleeding rate (P = 1.00), and recurrence-free survival rate (P = .717) were not significantly different between the patients who underwent TAE and those who underwent endoscopic hemostasis. Patients in the TAE group experienced more complications than those in the endoscopic hemostasis group (P < .001). Complications included mild intestinal ischemia (19.0%) and perforation requiring surgery (4.8%). Patients who required interventional radiotherapy were more likely to bleed from the right colon and presented with a systolic blood pressure of <80 mm Hg. TAE is an effective treatment for patients with colonic diverticular hemorrhage that is refractory to endoscopic hemostasis. However, complications must be monitored carefully.

Hypothermic machine perfusion for uterus transplantation

To describe the feasibility of hypothermic machine perfusion (HMP) in uterus transplantation (UT) to potentially improve the preservation of the uterus and enhance graft preservation in the donation after brainstem death (DBD) context. Uterus transplantation is a new surgical approach to treating absolute uterine infertility; it can be performed after living donation or after DBD. In the DBD context, the uterus is typically the last organ removed after other vital organs, with the exception of the Baylor team, which removes the uterus first. This key aspect imposes an unavoidable mild temperature ischemia for >1 hour on the uterus during the removal of the vital abdominal and chest organs. In renal transplantation, the perfusion machine reduces the risk of delayed graft function; thus, we hypothesized that machine perfusion could result in a reduction of uterus graft dysfunction. The uterus graft dysfunction could be expressed by a low embryo implantation rate, pregnancy loss, or vascular pregnancy diseases such as preeclampsia or fetal growth restriction." To date, static cold storage of the uterus is the only standard method for preservation before transplantation. HMP is an emerging method that could potentially improve the preservation of the uterus to enhance graft preservation in the DBD context. This video article shows all the technical details of using the HMP for uterine transplantation. University. Porcine model. Porcine uterus was retrieved from a DBD domestic animal model and flushed with KPS MP (Bridge To Life Ltd in UK) at 4 °C. After vascular preparation on the back table, the uterus was perfused using KPS MP through a cannula in the aorta using the VitaSmart device (Bridge To Life Ltd in UK) for 18 hours. Then, the uterus was transplanted to the porcine recipient. The macroscopic appearance of the uterus at the end of HMP and the assessment of the uterus vascularization after transplantation in the recipient compared with the native uterus. This video shows the cannulation of the iliac vessels, cooling and removal of the uterus on a porcine model, uterus preservation using HMP during 18 hours, and then UT in a new recipient pig with the reperfusion of the transplanted uterus next to the native, intact uterus of the recipient. The macroscopic appearance of the uterus at the end of HMP appeared viable and was perfectly flushed. The assessment of the uterus vascularization after transplantation in the recipient was similar to that of the native uterus. To our knowledge, we describe here for the first time the UT procedure in DBD context on an animal model and the use of HMP for uterus preservation in UT programs; this could increase the number of uterine grafts available for a greater number of femalerecipients. Hypothermic machine perfusion could allow the duration of cold ischemia to be prolonged without altering the uterine graft. Nevertheless, this assertion has to be validated in a human context.

Clinical and laboratory study of premature infants with hypoxic-ischemic encephalopathy

We conducted a comprehensive clinical and laboratory study of 102 preterm infants with hypoxic-ischemic encephalopathy (HIE) of varying gestational ages. All preterm infants were born to mothers with a complicated obstetric history. Clinical manifestation of CNS hypoxic-ischemic injury was observed in 100% of this cohort. Intracranial hemorrhages (ICH) of grades I-IV were registered in 38 (37.2%) cases, while periventricular leukomalacia (PVL) was present in 5 (4.9%) cases. Intrauterine growth restriction (IUGR) was observed in 36 (35.3%) cases, and respiratory distress syndrome (RDS) in 65 (63.7%) cases. Mild cerebral ischemia was diagnosed in 51 (50%) cases, moderate-severity cases in 32 (31.4%) cases, and severe CI in 19 (18.6%) preterm infants. The severity of clinical progression of HIE in preterm infants was shown to be dependent on gestational age, intrauterine hypoxia, and birth asphyxia. The health status of their mothers plays a crucial role in the development of CNS and other systemic injuries in preterm infants. Therefore, premature births remain a pertinent issue in modern society.

A retrospective study of endovascular repair of aortic dissection with aberrant right subclavian artery

Abstract: OBJECTIVES: Aortic dissection with aberrant right subclavian artery (ARSA) is rare but fatal, with its optimal treatment remaining controversial. In this retrospective study, we presented the outcome of endovascular repair for these patients, aiming to evaluate the efficacy and safety of this technique. MATERIALS AND METHODS: From January 2016 to January 2022, seven patients diagnosed with aortic dissection with ARSA in the First Affiliated Hospital of Sun Yat-sen University were enrolled. All these seven patients received thoracic endovascular aortic repair (TEVAR) within 1 week after their admission to our center. The data of baseline characteristics, imaging parameters, perioperative information, and follow-up were collected till March 2023. RESULTS: The mean age was 48.57 ± 9.41 years. Kommerell diverticulum was found in 2 (28.6%) patients. Among these seven patients, 4 (57.1%) were treated by TEVAR + branched stent graft + chimney technique, 2 (28.6%) were treated by TEVAR + chimney technique, and 1 (14.3%) was treated by TEVAR + chimney and periscope techniques. The mean time of procedures was 196.67 ± 31.18 min. Clinical success was achieved in 6 (85.7%) patients, while 1 (14.3%) patient died of nonaortic related cause. Bird beak configuration was discovered in 4 (57.1%) patients with an average length of 17.87 ± 3.93 mm and angle of 21.9° ±3.70°. One early type I endoleak and one mild cerebral ischemia were discovered, and recovered spontaneously before discharge. The diameter of the aorta remained stable, and no complication was found during the follow-up of the six patients. CONCLUSION: Endovascular repair of aortic dissection with ARSA was feasible and safe, with a favorable early to mid-term outcome.

Clinical outcomes of vacuum-dehydrated amniotic membrane (Omnigen) mounted on contact lens (Omnilenz) in eyes with acute chemical eye injuries

BackgroundOmnigen is a vacuum-dehydrated amniotic membrane transplant. It can be delivered to the eye pre-mounted on a special bandage contact lens (Omnilenz) that enables its application without the need for sutures or glue; the aim of this study is to evaluate the short-term clinical outcomes of Omnilenz-Omnigen complex in eyes with acute chemical injury (CEI).MethodsA prospective interventional study included patients with different grades of acute CEI attending the casualty between July 2021 and November 2022. All patients received first aid measures followed by the application of Omnilenz-Omnigen within the first 2 days. Patients were followed up for at least 1 month. Primary outcomes include epithelial defect and limbal ischemia. Secondary outcomes include best-corrected visual acuity (BCVA) and tolerability.ResultsThe study included 23 eyes of 21 patients with acute CEI mostly due to alcohol (34.8%). After the 1st application, the size of the epithelial defect showed a statistically significant reduction (p = 0.016) with improvement in BCVA (p < 0.001). Restoration of the limbal vascularity was obtained in 56.5% of the eyes. Repeated application of Omnilenz was required in 5 eyes (21.7%). The size of the epithelial defect was reduced after the second application (p = 0.504) with improved BCVA (p = 0.185). After 1st month, complete epithelial healing was achieved in all the eyes. Mild limbal ischemia persists in 3 (13%) of the eyes. Final BCVA showed statistically significant improvement (p < 0.001). None of the patients develops any serious complications.ConclusionOmnilenz proved to be easy to apply and well tolerated by patients, with promising clinical outcomes.

Left ventricular shape index and eccentricity index assessed by gated PET/CT. Promising parameters for detection of left ventricular remodelling

Abstract Funding Acknowledgements Type of funding sources: Public Institution(s). Main funding source(s): University of Groningen/University Medical Center Groningen. Background Left ventricular (LV) remodelling has been described as the pathway that precedes heart failure. This process consists of changes in the shape, size, volume and function of the left ventricle; all of this directly associated to increased risk of major adverse cardiac events (MACEs). Different parameters are used to evaluate cardiac geometry in multiple cardiac imaging modalities. In nuclear medicine, LV geometry can be studied through shape index (SI) and eccentricity index (EI). These values examine the degree of sphericity (SI) and elongation (EI) of the left ventricle. However, in cardiac perfusion PET/CT, the LV remodelling has not been extensively studied with SI and EI values, and their role is yet to be elucidated. Purpose This project aim to describe the role of SI and EI values in patients examined by gated 13N-ammonia PET/CT in ischemic and infarction scenario. Methods We retrospectively randomly selected 140 patients referred to 13N-ammonia PET/CT between 2016 and 2022 for suspected or diagnosed CAD. The patients were classified in 4 groups of 35 patients according to the presence and burden of ischemia or infarction: normal=0% of scar burden and ischemic burden; mild ischemia=5–10% of ischemic burden; moderate-severe ischemia≥10% of ischemic burden and infarction≥5% of scar burden. We collected the information regarding myocardial flows (myocardial blood flow (MBF) at rest, hyperaemic MBF at stress and coronary flow reserve (CFR)) and left ventricular geometry (SI end-diastolic at rest and stress, SI end-systolic at rest and stress, and EI at rest and stress). All the variables were automatically processed with QPS/QGS software. We performed a multicomparison analysis for the mentioned variables with One way ANOVA variance and Dunnett’s Test as Post Hoc, stablishing as the control the infarction group. Results The study population consisted of 35.7% women, all patients over 36 years old, with no significant differences between groups regarding the presence of cardiac risk factors. The control group showed important changes in all SI and EI when compared to the rest of the groups. With a maximum change of 0.090 observed in SI end-systolic stress in the mild ischemia group, and a minimum change of −0.041 in EI rest in the moderate-severe ischemia group. Control subjects had statistically significant higher values of SI end-diastolic rest (p&amp;lt;0.001) and stress (p = 0.005), end-systolic rest (p = 0.001)and stress (p&amp;lt;0.001) and statistically significant lower values of EI rest (p&amp;lt;0.001) and stress (p&amp;lt;0.001) when compared with all the other groups. Additionally, all SI and EI values in stress follow a linear change proportional to the degree of myocardial extend (Figure 1 and 2). Conclusions(s) SI and EI by 13N-ammonia PET/CT are variables that seem clinically relevant for the early detection of LV remodeling. However, there is still research to do for establishing cut-off values and evaluating the prediction of MACEs.

A new method incorporating deep learning with shape priors for left ventricular segmentation in myocardial perfusion SPECT images

Accurate segmentation of the left ventricle (LV) is crucial for evaluating myocardial perfusion SPECT (MPS) and assessing LV functions. In this study, a novel method combining deep learning with shape priors was developed and validated to extract the LV myocardium and automatically measure LV functional parameters. The method integrates a three-dimensional (3D) V-Net with a shape deformation module that incorporates shape priors generated by a dynamic programming (DP) algorithm to guide its output during training. A retrospective analysis was performed on an MPS dataset comprising 31 subjects without or with mild ischemia, 32 subjects with moderate ischemia, and 12 subjects with severe ischemia. Myocardial contours were manually annotated as the ground truth. A 5-fold stratified cross-validation was used to train and validate the models. The clinical performance was evaluated by measuring LV end-systolic volume (ESV), end-diastolic volume (EDV), left ventricular ejection fraction (LVEF), and scar burden from the extracted myocardial contours. There were excellent agreements between segmentation results by our proposed model and those from the ground truth, with a Dice similarity coefficient (DSC) of 0.9573 ± 0.0244, 0.9821 ± 0.0137, and 0.9903 ± 0.0041, as well as Hausdorff distances (HD) of 6.7529 ± 2.7334 mm, 7.2507 ± 3.1952 mm, and 7.6121 ± 3.0134 mm in extracting the LV endocardium, myocardium, and epicardium, respectively. Furthermore, the correlation coefficients between LVEF, ESV, EDV, stress scar burden, and rest scar burden measured from our model results and the ground truth were 0.92, 0.958, 0.952, 0.972, and 0.958, respectively. The proposed method achieved a high accuracy in extracting LV myocardial contours and assessing LV functions.

Relationship between the Castelli risk indeces and the presence and severity of ischemia in non-geriatric patients with suspected coronary artery disease

Aims: This study aimed to investigate the relationship between ischemia severity and Castelli risk indices (CRI) levels in non-geriatric patients with suspected coronary artery disease (CAD) referred to myocardial perfusion scintigraphy (MPS) with gated single photon emission computed tomography (SPECT).&#x0D; Material and Methods: This retrospective study included 417 non-geriatric patients referred to SPECT MPS for suspected CAD at the Cardiology Clinic between January 2019 and January 2021. Patients were divided into normal, mild, moderate, and severe ischemia groups according to MPS. CRIs were calculated as follows: CRI-I = total cholesterol / HDL ratio; CRI-II = LDL / HDL ratio.&#x0D; Results: The CRIs levels were higher in ischemia group than non-ischemia group. Increase in CRI-II level was associated with increased ischemia severity. Increased CRI-II level was found to be an independent predictor of mild, moderate and severe ischemia group, but CRI-I was similar in moderate and severe ischemia groups. The threshold value of CRI-II for predicting the presence of ischemia was &gt;2.1 (AUC ± SE = 0.787 ± 0.02, sensitivity = 79.5%, specificity = 71.4%). The threshold values of CRI-II showed a gradual increase in predicting the severity of ischemia.&#x0D; Conclusion: CRI-II offers offers gradually increasing threshold values in distinguishing patients with suspected CAD but without perfusion defects or determining its severity in the case of ischemia. CRI-II can be a potential screening tool for patients with suspected CAD and it can be used for risk stratification.

Biliary Metabolome Profiling for Evaluation of Liver Metabolism and Biliary Tract Function Related to Organ Preservation Method and Degree of Ischemia in a Porcine Model.

The development of surgical techniques, immunosuppressive strategies and new organ preservation methods have meant that transplant centers have to face the problem of an insufficient number of organs for transplantation concerning the constantly growing demand. Therefore, using organs from expanded criteria donors and developing new analytical solutions to find parameters or compounds that would allow a more efficient assessment of organ quality before transplantation are options for meeting this challenge. This study proposed bile metabolomic analysis to evaluate liver metabolism and biliary tract function depending on the organ preservation method and degree of warm ischemia time. The analyses were performed on solid-phase microextraction-prepared bile samples from porcine model donors with mild (heart beating donor [HBD]) and moderate warm ischemia (donation after circulatory death [DCD]) grafts subjected to static cold storage (SCS) or normothermic ex vivo liver perfusion (NEVLP) before transplantation. Bile produced in the SCS-preserved livers was characterized by increased levels of metabolites such as chenodeoxycholic acid, arachidonic acid and 5S-hydroxyeicosatetraeonic acid, as well as saturated and monounsaturated lysophosphatidylcholines (LPC). Such changes may be associated with differences in the bile acid synthesis pathways and organ inflammation. Moreover, it has been shown that NEVLP reduced the negative effect of ischemia on organ function. A linear relationship was observed between levels of lipids from the LPC group and the time of organ ischemia. This study identified metabolites worth considering as potential markers of changes occurring in preserved grafts.