Myocardial Viability Research Articles

The Utility of Low-Dose-Dobutamine Stress Echocardiography in Patients with Heart Failure with Reduced Ejection Fraction: An Update.

Despite significant advancements in medical therapy, heart failure with reduced ejection fraction (HFrEF) continues to be a significant cause of death and disability. Reversible ischaemic left ventricular dysfunction due to viable myocardium is one such contributing factor. In these cases, coronary revascularization has shown promise in improving left ventricular function and prognosis. For patients with HFrEF and wide QRS, cardiac resynchronization therapy (CRT) is an effective option to address electromechanical dyssynchrony. However, approximately 30% of patients do not respond positively to CRT, highlighting the need to refine candidate selection for this treatment. In some patients with reduced HFrEF, there is a condition known as classical low-flow, low-gradient aortic stenosis (AS) that may be observed. This condition is characterized by a low transaortic flow, which leads to reductions in both the transaortic mean gradient and aortic valve area. Decision-making regarding revascularization, CRT, and pharmacological treatment play a crucial role in managing HFrEF. Cardiac imaging can be valuable in guiding decision-making processes and assessing the prognosis of patients with HFrEF. Among the imaging modalities, dobutamine stress echocardiography has come a long way in establishing itself as a feasible, safe, effective, relatively cheap non-invasive technique. The aim of this review is to explore the current literature on the utility of low-dose stress echocardiography in diagnosing and prognosticating patients with HFrEF.

Dynamics of Non-Invasive Risk Factors of Sudden Cardiac Death after Myocardial Revascularization

Background: An attempt was made to study the effect of surgical myocardial revascularization on the processes of electrical myocardium instability underlying the occurrence of life-threatening ventricular arrhythmias, as well as the possibility of its non-invasive assessment by studying heart rate variability (HRV) and heart rate turbulence (HRT), as well as the duration and dispersion of the QT interval. Based only on the presence of viable myocardium, it is often impossible to predict the positive impact of revascularization on a patient’s prognosis, especially with reduced myocardial contractility. Moreover, given the well-studied relationship between myocardial remodeling and neurohormonal activation, non-invasive methods for assessing the autonomic regulation of cardiac activity can provide additional diagnostic information. Along with this, changes in these indicators and their prognostic role in patients with coronary artery disease after revascularization are subjects of discussion. Methods and Results: All patients underwent a comprehensive clinical and biochemical blood test, transthoracic echocardiography, tissue Doppler echocardiography, ultrasound examination of brachiocephalic arteries, selective coronary angio- and ventriculography, as well as Holter monitoring. Results show that a year after the coronary intervention, there was a significant positive trend in the frequency and structure of ventricular arrhythmias (VA). HRV indicators generally did not show significant dynamics. Only an increase in the values of the SDANN and low-frequency power (LFP) indices was noted, indicating a gradual increase in the activity of the sympathetic part of the autonomic nervous system. HRT indicators also did not show significant dynamics. A significant increase was found in the number of patients with no signs of impaired HRT. The average duration of the QT interval decreased significantly. There was also a tendency to shorten the corrected QT interval; however, it was insignificant. In terms of dispersion, both the QT interval and its corrected index, no significant dynamics were recorded in the general group of patients. Conclusion: Our study found that in patients with prior myocardial infarction, after revascularization, significant positive dynamics were recorded in life-threatening ventricular arrhythmias, but were unreliable for the indicators of autonomic regulation of cardiac activity, such as HRV and HRT.

Saved myocardium in acute ST-segment elevation myocardial infarction post-reperfusion: Analysis by cardiac magnetic resonance

To quantify by cardiovascular magnetic resonance the salvaged myocardium in the myocardium supplied by the infarct-related artery in reperfused and non-reperfused patients with a first ST-segment elevation myocardial infarction (STEMI). Twenty-five patients with a first STEMI (non-reperfused, ten patients; thrombolysis, ten patients; primary angioplasty, five patients) underwent cardiac magnetic resonance imaging 3 to 6 days after coronary angiography. Myocardial salvage and myocardial salvage index were quantified. Peak troponin values were lower in patients with primary angioplasty than in thrombolysis and non-reperfused patients (14,1 ng/ mL versus 515,4 ng/mL and 123,1 ng/mL, respectively; p < 0,007) and smaller infarct size (14,1 g versus 31,2 g and 31,5 g, respectively; p < 0,003). Myocardial salvage mass and myocardial salvage index were higher in patients with primary angioplasty than in thrombolysis and non-reperfused patients (27,4 g versus 4,7 g and 2,1 g, respectively; p < 0,003) and (65,2% versus 14,9% and 6,6%, respectively; p < 0,0001). The results of this study indicate the need to reassess the performance of coronary angioplasty and stent implantation in patients with a first STEMI, thrombolysis, and non-thrombolysis without prior myocardial viability studies. Cardiac magnetic resonance allows the quantification of salvaged myocardium and could be considered an emerging clinical application for the early evaluation of myocardial viability.

Photopolymerizable Hydrogel for Enhanced Intramyocardial Vascular Progenitor Cell Delivery and Post-Myocardial Infarction Healing.

Cell transplantation success for myocardial infarction (MI) treatment is often hindered by low engraftment due to washout effects during myocardial contraction. A clinically viable biomaterial that enhances cell retention can optimize intramyocardial cell delivery. In this study, a therapeutic cell delivery method is developed for MI treatment utilizing a photocrosslinkable gelatin methacryloyl (GelMA) hydrogel. Human vascular progenitor cells, capable of forming functional vasculatures upon transplantation, are combined with an in situ photopolymerization approach and injected into the infarcted zones of mouse hearts. This strategy substantially improves acute cell retention and promoteslong-term post-MI cardiac healing, including stabilized cardiac functions, preserved viable myocardium, and reduced cardiac fibrosis. Additionally, engrafted vascular cells polarize recruited bone marrow-derived neutrophils toward a non-inflammatory phenotype via transforming growth factor beta (TGFβ) signaling, fostering a pro-regenerative microenvironment. Neutrophil depletion negates the therapeutic benefits generated by cell delivery in ischemic hearts, highlighting the essential role of non-inflammatory, pro-regenerative neutrophils in cardiac remodeling. In conclusion, this GelMA hydrogel-based intramyocardial vascular cell delivery approach holds promise for enhancing the treatment of acute myocardial infarction.

Cardiac magnetic resonance imaging for myocardial viability assessment: Optimizing surgical revascularization in ischemic heart disease.

Patients with poor ejection fraction undergoing coronary artery bypass grafting carry higher operative risk and have poor long-term survival. Cardiac magnetic resonance is a useful modality to assess viability which can identify patients likely to benefit most from revascularization. In this study, we aimed to assess the outcome in patients selected for surgical revascularization by cardiac magnetic resonance imaging and identify predictors associated with poor outcomes. The study included patients with severely impaired left ventricular function but with at least six viable segments. Patients requiring emergency surgery, undergoing combined procedures, or where cardiopulmonary bypass was required were excluded. Cardiac magnetic resonance was carried out both preoperatively and at six months postoperatively by the same radiologist in all cases. Late gadolinium enhancement was used for the evaluation of myocardial viability. Amongst a total of 493 segments studied, there were 89 (18.1%) non-viable, 117 (23.7%) hibernating and 287 (58.2%) viable segments. At six months, the number of non-viable segments changed from 89 (18.1%) to 97 (19.7%), with an increase in viable segments from 287 (58.2%) to 374 (75.8%) and a corresponding reduction of hibernating segments from 117 (23.7%) to 22 (4.5%). There was improvement in ejection fraction from 28 ± 5.54 to 37 ± 5.86 (p < 0.0001) in the entire cohort at six months. Overall mortality was 1 (3.2%). Preoperative left ventricular end-systolic volume had the strongest negative correlation with post-operative ejection fraction. Cardiac magnetic resonance aided revascularization is associated with low mortality. Preoperative left ventricular end-systolic volume is an important determinant of postoperative ejection fraction.

Current Role of Myocardial Viability Imaging Using Positron Emission Tomography in Patients with Chronic Ischemic Heart Failure and Left Ventricular Dysfunction

Current Role of Myocardial Viability Imaging Using Positron Emission Tomography in Patients with Chronic Ischemic Heart Failure and Left Ventricular Dysfunction

Electrocardiogram and echocardiography findings and the outcomes of patients with myocardial infarction: Retrospective study in tertiary care hospitals in Northwest Ethiopia.

Myocardial infarction (MI) is diagnosed when there is a rise in cardiac biomarkers along with supportive evidence in the form of typical symptoms, suggestive electrocardiographic (ECG) changes, or imaging evidence of a new loss of viable myocardium or a new regional wall motion abnormality. The data regarding the use of ECG and echocardiography (Echo) findings and their impact on mortality are still lacking in Ethiopia. This study assessed the utilization of ECG and Echo findings and outcomes of patients with MI in tertiary care hospitals in Northwest Ethiopia. A retrospective chart review was conducted on patients with MI who were admitted to the adult intensive care units (ICUs) of two selected hospitals between January 2018 and July 30, 2021. Data was entered and analyzed using the SPSS 25 software. Logistic regression analysis was used to assess the association between in-hospital mortality and other variables. A P-value < 0.05 was considered significant. Among the 203 participants, 67.5% were male, and the mean age of the participants was 59 (13.8). Around two-thirds (66.5%) of patients had STEMI and a regional all-motion abnormality. More than half (54.1%) of the cases were in the anteroapical region. For MI, there was a 23.2% inconsistency between ECG and Echo findings. The rate of in-hospital mortality for patients with MI was 23%. Pulmonary hypertension [AOR = 7.8, 95% CI: 1.72-34.93], inferobasal regional wall motion abnormality [AOR = 7.9, 95% CI: 1.340-46.093], Killip's classes III and IV [AOR = 2.7, 95% CI: 1.103-6.314], infection [AOR = 3.2, 95% CI: 1.108-10.65], and ischemic stroke [AOR = 1.9, 95% CI: 1.091-5.222] were significantly associated with in-hospital mortality compared with their counterparts. The mortality of patients with MI in this study was higher than in other reports. Killip's class, pulmonary hypertension, infection, ischemic stroke, and inferobasal regional wall motion abnormalities were significantly associated with the in-hospital mortality of the patients with MI. There was a higher degree of inconsistency between ECG and Echo findings. The treatment of patients with MI should be tailored to their specific risk factors and causes.

Assessment of left ventricular tissue mitochondrial bioenergetics in patients with stable coronary artery disease

Recurrent myocardial ischemia can lead to left ventricular (LV) dysfunction in patients with coronary artery disease (CAD). In this observational cohort study, we assessed for chronic metabolomic and transcriptomic adaptations within LV myocardium of patients undergoing coronary artery bypass grafting. During surgery, paired transmural LV biopsies were acquired on the beating heart from regions with and without evidence of inducible ischemia on preoperative stress perfusion cardiovascular magnetic resonance. From 33 patients, 63 biopsies were acquired, compared to analysis of LV samples from 11 donor hearts. The global myocardial adenosine triphosphate (ATP):adenosine diphosphate (ADP) ratio was reduced in patients with CAD as compared to donor LV tissue, with increased expression of oxidative phosphorylation (OXPHOS) genes encoding the electron transport chain complexes across multiple cell types. Paired analyses of biopsies obtained from LV segments with or without inducible ischemia revealed no significant difference in the ATP:ADP ratio, broader metabolic profile or expression of ventricular cardiomyocyte genes implicated in OXPHOS. Differential metabolite analysis suggested dysregulation of several intermediates in patients with reduced LV ejection fraction, including succinate. Overall, our results suggest that viable myocardium in patients with stable CAD has global alterations in bioenergetic and transcriptional profile without large regional differences between areas with or without inducible ischemia.

Multi-modality cardiac image computing: A survey.

Multi-modality cardiac imaging plays a key role in the management of patients with cardiovascular diseases. It allows a combination of complementary anatomical, morphological and functional information, increases diagnosis accuracy, and improves the efficacy of cardiovascular interventions and clinical outcomes. Fully-automated processing and quantitative analysis of multi-modality cardiac images could have a direct impact on clinical research and evidence-based patient management. However, these require overcoming significant challenges including inter-modality misalignment and finding optimal methods to integrate information from different modalities. This paper aims to provide a comprehensive review of multi-modality imaging in cardiology, the computing methods, the validation strategies, the related clinical workflows and future perspectives. For the computing methodologies, we have a favored focus on the three tasks, i.e., registration, fusion and segmentation, which generally involve multi-modality imaging data, either combining information from different modalities or transferring information across modalities. The review highlights that multi-modality cardiac imaging data has the potential of wide applicability in the clinic, such as trans-aortic valve implantation guidance, myocardial viability assessment, and catheter ablation therapy and its patient selection. Nevertheless, many challenges remain unsolved, such as missing modality, modality selection, combination of imaging and non-imaging data, and uniform analysis and representation of different modalities. There is also work to do in defining how the well-developed techniques fit in clinical workflows and how much additional and relevant information they introduce. These problems are likely to continue to be an active field of research and the questions to be answered in the future.

SPECT-derived myocardial viability in patients with stable coronary artery disease and left ventricular dysfunction selected for surgical revascularization

SPECT-derived myocardial viability in patients with stable coronary artery disease and left ventricular dysfunction selected for surgical revascularization

Understanding the role of coronary artery revascularization in patients with left ventricular dysfunction and multivessel disease.

Coronary artery disease (CAD) is the most common cause of heart failure with reduced ejection fraction (HFrEF). Advances and innovations in medical therapy have been shown to play a crucial role in improving the prognosis of patients with CAD and HFrEF; however, mortality rate in these patients remains high, and the role of surgical and/or percutaneous revascularization strategy is still debated. The Surgical Treatment for Ischemic Heart Failure (STICH) trial and the Revascularization for Ischemic Ventricular Dysfunction (REVIVED) trial have attempted to provide an answer to this issue. Nevertheless, the results of these two trials have generated further uncertainties. Their findings do not provide a definitive answer about the ideal clinical phenotype for surgical or percutaneous coronary revascularization and dispute the historical dogma on myocardial viability and the theory of myocardial hibernation, raising new questions about the proper selection of patients who are candidates for coronary revascularization. The aim of this review is to provide an overview on the actual available evidence of coronary artery revascularization in patients with CAD and left ventricular dysfunction and to suggest new insights on the proper selection and management strategies in this high-risk clinical setting.

Stem cell-derived exosome patch with coronary artery bypass graft restores cardiac function in chronically ischemic porcine myocardium

ObjectiveThis study aimed to investigate whether or not the application of a stem cell-derived exosome-laden collagen patch (EXP) during coronary artery bypass grafting (CABG) can recover cardiac function by modulating mitochondrial bioenergetics and myocardial inflammation in hibernating myocardium (HIB), which is defined as myocardium with reduced blood flow and function that retains viability and variable contractile reserve. MethodsIn vitro methods involved exposing H9C2 cardiomyocytes to hypoxia followed by normoxic coculture with porcine mesenchymal stem cells. Mitochondrial respiration was measured using Seahorse assay. GW4869, an exosomal release antagonist, was used to determine the effect of mesenchymal stem cells-derived exosomal signaling on cardiomyocyte recovery. Total exosomal RNA was isolated and differential micro RNA expression determined by sequencing. In vivo studies comprised 48 Yorkshire-Landrace juvenile swine (6 normal controls, 17 HIB, 19 CABG, and 6 CABG + EXP), which were compared for physiologic and metabolic changes. HIB was created by placing a constrictor on the proximal left anterior descending artery, causing significant stenosis but preserved viability by 12 weeks. CABG was performed with or without mesenchymal stem cells-derived EXP application and animals recovered for 4 weeks. Before terminal procedure, cardiac magnetic resonance imaging at rest, and with low-dose dobutamine, assessed diastolic relaxation, systolic function, graft patency, and myocardial viability. Tissue studies of inflammation, fibrosis, and mitochondrial morphology were performed posttermination. ResultsIn vitro data demonstrated improved cardiomyocyte mitochondrial respiration upon coculture with MSCs that was blunted when adding the exosomal antagonist GW4869. RNA sequencing identified 8 differentially expressed micro RNAs in normoxia vs hypoxia-induced exosomes that may modulate the expression of key mitochondrial (peroxisome proliferator-activator receptor gamma coactivator 1-alpha and adenosine triphosphate synthase) and inflammatory mediators (nuclear factor kappa-light-chain enhancer of activated B cells, interferon gamma, and interleukin 1β). In vivo animal magnetic resonance imaging studies demonstrated regional systolic function and diastolic relaxation to be improved with CABG + EXP compared with HIB (P = .02 and P = .02, respectively). Histologic analysis showed increased interstitial fibrosis and inflammation in HIB compared with CABG + EXP. Electron microscopy demonstrated increased mitochondrial area, perimeter, and aspect ratio in CABG + EXP compared with HIB or CABG alone (P < .0001). ConclusionsExosomes recovered cardiomyocyte mitochondrial respiration and reduced myocardial inflammation through paracrine signaling, resulting in improved cardiac function.

Baseline angina burden predicts quality of life and functional improvement in patients with viable myocardium treated for chronic total occlusion

Chronic total occlusion (CTO) is a common finding in patients with known or suspected coronary artery disease and has a distinctive role in these patients’ quality of life. However, there is still a lack of evidence of correct patient selection for percutaneous coronary intervention (PCI). From July 2017 to August 2020, 68 patients with successful PCI of a CTO and previous evidence of viability for PCI by cardiovascular magnetic resonance imaging (CMR) were prospectively included in this single-centre observational study. Of these patients, 62 underwent follow-up CMR, and 56 underwent surveys using the Seattle Angina Questionnaire before PCI and 3, 12 and 24 months after PCI. The CMR results were assessed for volumetric, functional and deformation parameters. From the baseline to the follow-up, there was a significant reduction in the left ventricular volumes (all p < 0.001) and an increase in the left ventricular ejection fraction (57.6 ± 11.6% vs. 60.3 ± 9.4%, p = 0.006). Among the deformation parameters, only the left ventricular radial strain showed significant improvement. The SAQ showed an early improvement that emphasised angina stability and frequency as well as a summary score, which persisted after 24 months. A low SAQ summary score before PCI was the best predictive factor of good clinical improvement thereafter. Improvements in myocardial function and quality of life can be achieved with PCI of a CTO. Patient selection for PCI should be performed primarily among relevantly symptomatic patients when evidence of viability for PCI is present. The SAQ can help guide such patient selection.Trial registration ISRCTN, identifier: ISRCTN33203221. Retrospectively registered on 01.04.2020. https://www.isrctn.com/ISRCTN33203221

Association between residual unipolar voltage and arrhythmia recurrence after left atrial posterior wall isolation for persistent atrial fibrillation.

Posterior wall isolation (PWI) combined with pulmonary vein isolation (PVI) has proven effective for persistent atrial fibrillation (AF). However, when performing PWI, creating transmural lesions with subendocardial ablation is sometimes difficult. Endocardial unipolar voltage amplitude had a higher sensitivity than bipolar voltage mapping for identifying intramural viable myocardium in the atria. In this study, we aimed to retrospectively investigate the correlation between the residual potential in the posterior wall (PW) following PWI for persistent AF and atrial arrhythmia recurrence using endocardial unipolar voltage. This was a single-center observational study. Patients who underwent PVI and PWI for persistent AF in the first procedure between March 2018 and December 2021 at the Tokyo Metropolitan Hiroo Hospital were included in this study. The patients were divided into two groups based on the presence of residual unipolar PW potentials after PWI with a cutoff of 1.08 mV and the recurrence of atrial arrhythmias was compared. In total, 109 patients were included in the analysis. Forty-three patients had residual unipolar potentials after PWI and 66 patients had no residual unipolar potentials. The atrial arrhythmia recurrence rate was significantly higher in the group with residual unipolar potential (41.8% vs. 17.9%, p = 0.003). The residual unipolar potential was an independent predictor of recurrence (odds ratio: 4.53; confidence interval: 1.67-12.3, p = 0.003). Residual unipolar potential after PWI for persistent AF is associated with recurrent atrial arrhythmias.

A Prospective Comparative Study between 99mTc MIBI Myocardial Perfusion Single-Photon Emission Computed Tomography and Dobutamine Stress Echocardiography to Detect Viable Myocardium in Patients with Coronary Artery Disease.

The objective of this study was to compare 99mTc MIBI myocardial perfusion SPECT and Dobutamine Stress Echocardiography (DSE) in detecting viable myocardium in patients with Coronary Artery Disease. Total of 50 patients who with CAD and poor LV function were idenitifed on 2D Echo using 16 segment cardiac model. These patients underwent 99mTc MIBI myocardial perfusion SPECT and Dobutamine Stress Echocardiography and the results were compared with the gold standard 18F-FDG PET-CT findings. A Total of 550 dysfunctional segments were identified in datasets of 50 patients on 2D echo. No significant difference was noted between the pairwise positive outcome of viable segment between MIBI SPECT and DSE (p=0.875). MIBI SPECT showed a sensitivity of 86.5% and specificity of 90.0% when compared with 18F-FDG PET-CT which was comparable with DSE having a sensitivity of 87.6% and specificity of 90.7%. 99mTc MIBI SPECT is an effective good alternative for evaluation of viable myocardial segments in patients with dysfunctional myocardium and can be considered especially in elderly or obese patients and patients with lung disease having poor echocardiographic imaging window due to lack of an optimal acoustic window.

Site-specific prolongation of repolarization prevents postmyocardial infarction tachycardia.

Site-specific prolongation of repolarization prevents postmyocardial infarction tachycardia.

MyoPS: A benchmark of myocardial pathology segmentation combining three-sequence cardiac magnetic resonance images

Assessment of myocardial viability is essential in diagnosis and treatment management of patients suffering from myocardial infarction, and classification of pathology on the myocardium is the key to this assessment. This work defines a new task of medical image analysis, i.e., to perform myocardial pathology segmentation (MyoPS) combining three-sequence cardiac magnetic resonance (CMR) images, which was first proposed in the MyoPS challenge, in conjunction with MICCAI 2020. Note that MyoPS refers to both myocardial pathology segmentation and the challenge in this paper. The challenge provided 45 paired and pre-aligned CMR images, allowing algorithms to combine the complementary information from the three CMR sequences for pathology segmentation. In this article, we provide details of the challenge, survey the works from fifteen participants and interpret their methods according to five aspects, i.e., preprocessing, data augmentation, learning strategy, model architecture and post-processing. In addition, we analyze the results with respect to different factors, in order to examine the key obstacles and explore the potential of solutions, as well as to provide a benchmark for future research. The average Dice scores of submitted algorithms were 0.614±0.231 and 0.644±0.153 for myocardial scars and edema, respectively. We conclude that while promising results have been reported, the research is still in the early stage, and more in-depth exploration is needed before a successful application to the clinics. MyoPS data and evaluation tool continue to be publicly available upon registration via its homepage (www.sdspeople.fudan.edu.cn/zhuangxiahai/0/myops20/).

FOXN4 affects myocardial ischemia-reperfusion injury through HIF-1α/MMP2-mediated ferroptosis of cardiomyocytes.

Myocardial ischemia-reperfusion injury (MIRI) is an important factor leading to myocardial injury and necrosis, and can induce ischemic heart disease. Forkhead box protein N4 (FOXN4) belongs to the gene family of Fork head domain (Fox) transcription factors and plays an important role in heart formation and function. However, whether FOXN4 is involved in MIRI progression is unknown. In this study, we investigated the clinicopathological significance and potential mechanisms of FOXN4 in MIRI. The expressions of FOXN4 and MMP2 were measured by quantitative reverse transcriptase polymerase chain reaction, apoptosis was detected by flow cytometry, and cell viability was detected by examining EdU incorporation into DNA. The signaling pathway related proteins FOXN4, MMP2, HIF-1α, apoptosis-related proteins Bcl-2 and Bax, and ferroptosis-related proteins TFR1 and IREB2 were detected by western blot, the levels of malondialdehyde (MDA), Fe2+, reactive oxygen species (ROS), and glutathione were detected by commercially available kits, and the cardiac histopathology after MIRI was evaluated by hematoxylin and eosin staining. We found that knockdown of FOXN4 alleviated oxidative stress, inhibited ROS production, and inhibited ferroptosis in MIR-injured tissues and cardiomyocytes. In addition, knockdown of FOXN4 inhibited myocardial injury, improved myocardial cell viability, restored myocardial function, and alleviated MIRI. We interrogated the mechanism and found that FOXN4 can enhance its binding to HIF-1α, up-regulate the expression of MMP2, and mediate ferroptosis to regulate the functional activity of cardiomyocytes to affect the progression of MIRI. This study provides new insights into the role of FOXN4 in MIRI progression and suggests that FOXN4 may represent a potential therapeutic target in MIRI progression by regulating the active function of cardiomyocytes through HIF-1α/MMP2-mediated ferroptosis.

The role of molecular imaging in the comprehensive examination of HIV-patients with ischemic heart disease

Cardiovascular disease is one of the most frequent cause of death globally. The greatest part is occupied by ischemic heart disease. HIV patients are composed to a higher risk of coronary heart disease.The purpose of this work is to evaluate the possibility of using molecular imaging methods in a comprehensive examination of patients with HIV infection and ischemic heart disease.Materials and methods. The survey group includes 32 patients with HIV infection. The comparison group consists of 25 age-matched patients with coronary heart disease and without HIV Infection. All patients were underwent myocardial perfusion scintigraphy using single photon emission computed tomography. Positron emission tomography with FDG were performed if necessary to assess the viability of the myocardium. The patients of the main group undergo diagnostic coronary angiography and standard set of laboratory and institutional diagnostic methods.Results. The results of which confirm the high efficiency of radionuclide diagnostic methods for detecting perfusion disorders, contractility and myocardial viability in patients with HIV infection even at an early stage. They can be recommended for using in a comprehensive examination of patients with HIV infection.

Indipendent predictors of akinetic segment recovery during dobutamine infusion assessed by cardiac magnetic resonance

Abstract Funding Acknowledgements Type of funding sources: None. Background Myocardial viability assessment can guide myocardial revascularization in patients with coronary artery disease. Non-invasive imaging modalities are routinely used for detection of viable myocardium and the highest diagnostic performance is provided by Cardiac Magnetic Resonance (CMR): it combines high sensibility (95%) by delayed enhancement (DE) assessment and high specificity (91%) by evaluation of myocardial systolic thickening recovery at increasing dose of dobutamine (Db-systolic recovery). Purpose Identification of independent predictors for Db-systolic recovery of akinetic segments supplied by a chronic total occlusion (CTO) coronary artery. The second purpose was to develop a diagnostic tool as alternative to dobutamine stress imaging to provide an estimation of myocardial response to inotropic agents. Methods This single center prospective observational study enrolled 47 consecutive patients referred to CMR for evaluation of inducible ischemia and myocardial viability in the territory of one or more CTOs. All enrolled patients presented basal akinetic segments in the CTO territory. Cine-Steady State Free Precession (SSFP) sequences were acquired both in basal and at increasing dose of dobutamine to evaluate Db-systolic recovery. Stress perfusion imaging and DE were then acquired to detect inducible ischemia and necrotic areas. Post-processing CMR-Feature Tracking strain analysis provided both radial and circumferential strain on basal, mid and apical short axis planes. Results Table 1 lists clinical characteristics of the study population. A total of 189 akinetic segments supplied by a CTO were detected and divided into viable and non-viable groups according to their ability to recover or not at increasing dose of dobutamine, respectively. Parameters of each akinetic segment significantly (p value &amp;lt; 0.05) associated with viability at univariate analysis were included in the multivariable binary logistic regression to identify independent predictors of Db-systolic recovery (Table 2). These independent predictors have been then included in a logistic regression model as continuous variable except for Transmural Extent of DE which can be either 1 or 0 according to DE&amp;lt;75% or ≥75%, respectively: L= −5.459 + 0.033 * (Radial Peak Systolic Strain) + 0.067 * (Circumferential Endocardial Peak Systolic Strain) + 1.808 * (Transmural Extent of DE) + 0.358 * (Diastolic Wall Thickness). When L ≥ 0 the model predicts contractile recovery during dobutamine infusion with an accuracy of 83.1%. Conclusion This CMR prospective study identifies independent predictors of contractile recovery at increasing dose of dobutamine and provides a diagnostic tool which might substitute dobutamine assessment with a good accuracy, reducing acquisition time and adverse events in patients with CTOs. An external validation study is needed to assess the consistency of this model for clinical purposes.