The Nephroprotective Effect of Nitric Oxide during Extracorporeal Circulation: An Experimental Study.

This study aims to determine the effectiveness of administering 80 ppm nitric oxide in reducing kidney injury, mitochondrial dysfunction and regulated cell death in kidneys during experimental perfusion. Twenty-four sheep were randomized into four groups: two groups received 80 ppm NO conditioning with 90 min of cardiopulmonary bypass (CPB + NO) or 90 min of CPB and hypothermic circulatory arrest (CPB + CA + NO), while two groups received sham protocols (CPB and CPB + CA). Kidney injury was assessed using laboratory (neutrophil gelatinase-associated lipocalin, an acute kidney injury biomarker) and morphological methods (morphometric histological changes in kidney biopsy specimens). A kidney biopsy was performed 60 min after weaning from mechanical perfusion. NO did not increase the concentrations of inhaled NO2 and methemoglobin significantly. The NO-conditioning groups showed less severe kidney injury and mitochondrial dysfunction, with statistical significance in the CPB + NO group and reduced tumor necrosis factor-α expression as a trigger of apoptosis and necroptosis in renal tissue in the CPB + CA + NO group compared to the CPB + CA group. The severity of mitochondrial dysfunction in renal tissue was insignificantly lower in the NO-conditioning groups. We conclude that NO administration is safe and effective at reducing kidney injury, mitochondrial dysfunction and regulated cell death in kidneys during experimental CPB.

Assessment of continuous low-dose and high-dose burst of inhaled nitric oxide in spontaneously breathing COVID-19 patients: A randomized controlled trial.

BACKGROUND: Inhaled nitric oxide (iNO) showed to improve oxygenation at low doses by reducing intrapulmonary shunt and to display antiviral properties at high doses. To assess the safety and potential benefits, we designed an exploratory clinical trial comparing low-dose with intermittent high-dose iNO to only intermittent high-dose iNO in hypoxemic COVID-19 patients. METHODS: In this single-center interventional non-inferiority randomized trial (ClinicalTrials.gov, NCT04476992), twenty oxygen-dependent COVID-19 patients were randomly assigned to the high-dose (200 ppm for 30 min) + continuous low-dose (20 ppm) iNO group (iNO200/20) or the high-dose iNO group (iNO200). Methemoglobinemia (MetHb) assessed 48 h after iNO initiation was the primary endpoint. Reverse-transcription polymerase chain reaction for SARS-CoV-2, inflammatory markers during hospitalization, and heart ultrasounds during the iNO200 treatments were evaluated. RESULTS: MetHb difference between iNO groups remained within the non-inferiority limit of 3 %, indicating comparable treatments despite being statistically different (p-value<0.01). Both groups presented similar SpO2/FiO2 ratio at 48 h (iNO200 vs. iNO200/20 341[334-356] vs. 359 [331-380], respectively, p-value = 0.436). Both groups showed the same time to SARS-CoV-2 negativization, hospital length of stay, and recovery time. iNO-treated patients showed quicker SARS-CoV-2 negativization compared to a similar group of non-iNO patients (HR 2.57, 95%CI 1.04-6.33). During the 228 treatments, iNO200 and iNO200/20 groups were comparable for safety, hemodynamic stability, and respiratory function improvement. CONCLUSIONS: iNO200/20 and iNO200 are equally safe in non-intubated patients with COVID-19-induced respiratory failure with regards to MetHb and NO2. Larger studies should investigate whether iNO200/20 leads to better outcomes compared to non-iNO treated patients.

Peptides Are Cardioprotective Drugs of the Future: The Receptor and Signaling Mechanisms of the Cardioprotective Effect of Glucagon-like Peptide-1 Receptor Agonists.

The high mortality rate among patients with acute myocardial infarction (AMI) is one of the main problems of modern cardiology. It is quite obvious that there is an urgent need to create more effective drugs for the treatment of AMI than those currently used in the clinic. Such drugs could be enzyme-resistant peptide analogs of glucagon-like peptide-1 (GLP-1). GLP-1 receptor (GLP1R) agonists can prevent ischemia/reperfusion (I/R) cardiac injury. In addition, chronic administration of GLP1R agonists can alleviate the development of adverse cardiac remodeling in myocardial infarction, hypertension, and diabetes mellitus. GLP1R agonists can protect the heart against oxidative stress and reduce proinflammatory cytokine (IL-1ß, TNF-α, IL-6, and MCP-1) expression in the myocardium. GLP1R stimulation inhibits apoptosis, necroptosis, pyroptosis, and ferroptosis of cardiomyocytes. The activation of the GLP1R augments autophagy and mitophagy in the myocardium. GLP1R agonists downregulate reactive species generation through the activation of Epac and the GLP1R/PI3K/Akt/survivin pathway. The GLP1R, kinases (PKCε, PKA, Akt, AMPK, PI3K, ERK1/2, mTOR, GSK-3ß, PKG, MEK1/2, and MKK3), enzymes (HO-1 and eNOS), transcription factors (STAT3, CREB, Nrf2, and FoxO3), KATP channel opening, and MPT pore closing are involved in the cardioprotective effect of GLP1R agonists.

Multiple Phenotypes of Chronic Coronary Syndromes Identified by ABCDE Stress Echocardiography.

BACKGROUND: Regional wall motion abnormality is considered a sensitive and specific marker of ischemia during stress echocardiography (SE). However, ischemia is a multifaceted entity associated with either coronary artery disease (CAD) or angina with normal coronary arteries, a distinction difficult to make using a single sign. The aim of this study was to evaluate the diagnostic potential of the five-step ABCDE SE protocol for CAD detection. METHODS: From the 2016-2022 Stress Echo 2030 study data bank, 3,229 patients were selected (mean age, 66 ± 12 years; 2,089 men [65%]) with known CAD (n = 1,792) or angina with normal coronary arteries (n = 1,437). All patients were studied using both the ABCDE SE protocol and coronary angiography, within 3 months. In step A, regional wall motion abnormality is assessed; in step B, B-lines and diastolic function; in step C, left ventricular contractile reserve; in step D, coronary flow velocity reserve in the left anterior descending coronary artery; and in step E, heart rate reserve. RESULTS: SE response ranged from a score of 0 (all steps normal) to a score of 5 (all steps abnormal). For CAD, rates of abnormal results were 347 for step A (19.4%), 547 (30.5%) for step B, 720 (40.2%) for step C, 615 (34.3%) for step D, and 633 (35.3%) for step E. For angina with normal coronary arteries, rates of abnormal results were 81 (5.6%) for step A, 429 (29.9%) for step B, 432 (30.1%) for step C, 354 (24.6%) for step D, and 445 (31.0%) for step E. The dominant "solitary phenotype" was step B in 109 patients (9.1%). CONCLUSIONS: Stress-induced ischemia presents with a wide range of diagnostic phenotypes, highlighting its complex nature. Using a comprehensive approach such as the advanced ABCDE score, which combines multiple markers, proves to be more valuable than relying on a single marker in isolation.

Intermediate Monocytes and Circulating Endothelial Cells: Interplay with Severity of Atherosclerosis in Patients with Coronary Artery Disease and Type 2 Diabetes Mellitus.

The aim was to investigate the association of monocyte heterogeneity and presence of circulating endothelial cells with the severity of coronary atherosclerosis in patients with coronary artery disease (CAD) and type 2 diabetes mellitus (T2DM). We recruited 62 patients with CAD, including 22 patients with DM2. The severity of atherosclerosis was evaluated using Gensini Score. Numbers of classical (CD14++CD16-), intermediate (CD14++CD16+), and non-classical (CD14+CD16++) monocyte subsets; circulating endothelial progenitor cells; and the presence of circulating endothelial cells were evaluated. Counts and frequencies of intermediate monocytes, but not glycaemia parameters, were associated with the severity of atherosclerosis in diabetic CAD patients (rs = 0.689; p = 0.001 and rs = 0.632; p = 0.002, respectively). Frequency of Tie2+ cells was lower in classical than in non-classical monocytes in CAD patients (p = 0.007), while in patients with association of CAD and T2DM, differences between Tie2+ monocytes subsets disappeared (p = 0.080). Circulating endothelial cells were determined in 100% of CAD+T2DM patients, and counts of CD14++CD16+ monocytes and concentration of TGF-ß predicted the presence of circulating endothelial cells (sensitivity 92.3%; specificity 90.9%; AUC = 0.930). Thus, intermediate monocytes represent one of the key determinants of the appearance of circulating endothelial cells in all the patients with CAD, but are associated with the severity of atherosclerosis only in patients with association of CAD and T2DM.

Rest and Stress Left Atrial Dysfunction in Patients with Atrial Fibrillation.

BACKGROUND: Left atrial (LA) myopathy with paroxysmal and permanent atrial fibrillation (AF) is frequent in chronic coronary syndromes (CCS) but sometimes occult at rest and elicited by stress. AIM: This study sought to assess LA volume and function at rest and during stress across the spectrum of AF. METHODS: In a prospective, multicenter, observational study design, we enrolled 3042 patients [age = 64 ± 12; 63.8% male] with known or suspected CCS: 2749 were in sinus rhythm (SR, Group 1); 191 in SR with a history of paroxysmal AF (Group 2); and 102 were in permanent AF (Group 3). All patients underwent stress echocardiography (SE). We measured left atrial volume index (LAVI) in all patients and LA Strain reservoir phase (LASr) in a subset of 486 patients. RESULTS: LAVI increased from Group 1 to 3, both at rest (Group 1 = 27.6 ± 12.2, Group 2 = 31.6 ± 12.9, Group 3 = 43.3 ± 19.7 mL/m2, p < 0.001) and at peak stress (Group 1 = 26.2 ± 12.0, Group 2 = 31.2 ± 12.2, Group 3 = 43.9 ± 19.4 mL/m2, p < 0.001). LASr progressively decreased from Group 1 to 3, both at rest (Group 1 = 26.0 ± 8.5%, Group 2 = 23.2 ± 11.2%, Group 3 = 8.5 ± 6.5%, p < 0.001) and at peak stress (Group 1 = 26.9 ± 10.1, Group 2 = 23.8 ± 11.0 Group 3 = 10.7 ± 8.1%, p < 0.001). Stress B-lines (≥2) were more frequent in AF (Group 1 = 29.7% vs. Group 2 = 35.5% vs. Group 3 = 57.4%, p < 0.001). Inducible ischemia was less frequent in SR (Group 1 = 16.1% vs. Group 2 = 24.7% vs. Group 3 = 24.5%, p = 0.001). CONCLUSIONS: In CCS, rest and stress LA dilation and reservoir dysfunction are often present in paroxysmal and, more so, in permanent AF and are associated with more frequent inducible ischemia and pulmonary congestion during stress.

Do reactive oxygen species damage or protect the heart in ischemia and reperfusion? Analysis on experimental and clinical data.

The role of reactive oxygen species (ROS) in ischemic and reperfusion (I/R) injury of the heart has been discussed for more than 40 years. It has been demonstrated that reperfusion triggers a multiple increase in free radical generation in the isolated heart. Antioxidants were found to have the ability to mitigate I/R injury of the heart. However, it is unclear whether their cardioprotective effect truly depends on the decrease of ROS levels in myocardial tissues. Since high doses and high concentrations of antioxidants were experimentally used, it is highly likely that the cardioprotective effect of antioxidants depends on their interaction not only with free radicals but also with other molecules. It has been demonstrated that the antioxidant N-2-mercaptopropionyl glycine or NDPH oxidase knockout abolished the cardioprotective effect of ischemic preconditioning. Consequently, there is evidence that ROS protect the heart against the I/R injury.

A historical literature review of coronary microvascular obstruction and intra-myocardial hemorrhage as functional/structural phenomena.

The analysis of experimental data demonstrates that platelets and neutrophils are involved in the no-reflow phenomenon, also known as microvascular obstruction (MVO). However, studies performed in the isolated perfused hearts subjected to ischemia/reperfusion (I/R) do not suggest the involvement of microembolization and microthrombi in this phenomenon. The intracoronary administration of alteplase has been found to have no effect on the occurrence of MVO in patients with acute myocardial infarction. Consequently, the major events preceding the appearance of MVO in coronary arteries are independent of microthrombi, platelets, and neutrophils. Endothelial cells appear to be the target where ischemia can disrupt the endothelium-dependent vasodilation of coronary arteries. However, reperfusion triggers more pronounced damage, possibly mediated by pyroptosis. MVO and intra-myocardial hemorrhage contribute to the adverse post-infarction myocardial remodeling. Therefore, pharmacological agents used to treat MVO should prevent endothelial injury and induce relaxation of smooth muscles. Ischemic conditioning protocols have been shown to prevent MVO, with L-type Ca 2+ channel blockers appearing the most effective in treating MVO.

The Signaling Mechanism of Remote Postconditioning of the Heart: Prospects of the Use of Remote Postconditioning for the Treatment of Acute Myocardial Infarction.

Acute myocardial infarction (AMI) remains the leading cause of mortality in the world, highlighting an urgent need for the development of novel, more effective approaches for the treatment of AMI. Remote postconditioning (RPost) of the heart could be a useful approach. It was demonstrated that RPost triggers infarct size reduction, improves contractile function of the heart in reperfusion, mitigates apoptosis, and stimulates autophagy in animals with coronary artery occlusion and reperfusion. Endogenous opioid peptides and adenosine could be involved in RPost. It was found that kinases and NO-synthase participate in RPost. KATP channels, MPT pore, and STAT3 could be hypothetical end-effectors of RPost. Metabolic syndrome and old age abolish the cardioprotective effect of RPost in rats. The data on the efficacy of RPost in clinical practice are inconsistent. These data are discussed in the review.

KATP channels are regulators of programmed cell death and targets for the creation of novel drugs against ischemia/reperfusion cardiac injury.

BACKGROUND: The use of percutaneous coronary intervention (PCI) in patients with ST-segment elevation myocardial infarction (STEMI) is associated with a mortality rate of 5%-7%. It is clear that there is an urgent need to develop new drugs that can effectively prevent cardiac reperfusion injury. ATP-sensitive K+ (KATP ) channel openers (KCOs) can be classified as such drugs. RESULTS: KCOs prevent irreversible ischemia and reperfusion injury of the heart. KATP channel opening promotes inhibition of apoptosis, necroptosis, pyroptosis, and stimulation of autophagy. KCOs prevent the development of cardiac adverse remodeling and improve cardiac contractility in reperfusion. KCOs exhibit antiarrhythmic properties and prevent the appearance of the no-reflow phenomenon in animals with coronary artery occlusion and reperfusion. Diabetes mellitus and a cholesterol-enriched diet abolish the cardioprotective effect of KCOs. Nicorandil, a KCO, attenuates major adverse cardiovascular event and the no-reflow phenomenon, reduces infarct size, and decreases the incidence of ventricular arrhythmias in patients with acute myocardial infarction. CONCLUSION: The cardioprotective effect of KCOs is mediated by the opening of mitochondrial KATP (mitoKATP ) and sarcolemmal KATP (sarcKATP ) channels, triggered free radicals' production, and kinase activation.

Association of Epicardial Adipose Tissue Adipocytes Hypertrophy with Biomarkers of Low-Grade Inflammation and Extracellular Matrix Remodeling in Patients with Coronary Artery Disease.

The aim of the study was to compare the morphological features of epicardial adipose tissue (EAT) adipocyte with the circulating inflammatory biomarkers and parameters of extracellular matrix remodeling in patients with coronary artery disease (CAD). We recruited 42 patients with CAD (m/f 28/14) who were scheduled for coronary artery bypass graft surgery (CABG). EAT adipocytes were obtained by the enzymatic method from intraoperative adipose tissue samples. Concentrations of secreted and lipoprotein-associated phospholipase A2 (sPLA2 and LpPLA2), TNF-α, IL-1ß, IL-6, IL-10, high-sensitive C-reactive protein (hsCRP), metalloproteinase-9 (MMP-9), MMP-2, C-terminal cross-linking telopeptide of type I collagen (CTX-I), and tissue inhibitor of metalloproteinase 1 (TIMP-1) were measured in blood serum. Patients were divided into two groups: group 1-with mean EAT adipocytes' size ≤ 87.32 µm; group 2-with mean EAT adipocytes' size > 87.32 µm. Patients of group 2 had higher concentrations of triglycerides, hsCRP, TNF-α, and sPLA2 and a lower concentration of CTX-I. A multiple logistic regression model was created (RN2 = 0.43, p = 0.0013). Concentrations of TNF-α, sPLA2 and CTX-I appeared to be independent determinants of the EAT adipocyte hypertrophy. ROC analysis revealed the 78% accuracy, 71% sensitivity, and 85% specificity of the model, AUC = 0.82. According to our results, chronic low-grade inflammation and extracellular matrix remodeling are closely associated with the development of hypertrophy of EAT adipocytes, with serum concentrations of TNF-α, sPLA2 and CTX-I being the key predictors, describing the variability of epicardial adipocytes' size.

Regulation of autophagy of the heart in ischemia and reperfusion.

Ischemia/reperfusion (I/R) of the heart leads to increased autophagic flux. Preconditioning stimulates autophagic flux by AMPK and PI3-kinase activation and mTOR inhibition. The cardioprotective effect of postconditioning is associated with activation of autophagy and increased activity of NO-synthase and AMPK. Oxidative stress stimulates autophagy in the heart during I/R. Superoxide radicals generated by NADPH-oxidase acts as a trigger for autophagy, possibly due to AMPK activation. There is reason to believe that AMPK, GSK-3ß, PINK1, JNK, hexokinase II, MEK, PKCα, and ERK kinases stimulate autophagy, while mTOR, PKCδ, Akt, and PI3-kinase can inhibit autophagy in the heart during I/R. However, there is evidence that PI3-kinase could stimulate autophagy in ischemic preconditioning of the heart. It was found that transcription factors FoxO1, FoxO3, NF-κB, HIF-1α, TFEB, and Nrf-2 enhance autophagy in the heart in I/R. Transcriptional factors STAT1, STAT3, and p53 inhibit autophagy in I/R. MicroRNAs could stimulate and inhibit autophagy in the heart in I/R. Long noncoding RNAs regulate the viability and autophagy of cardiomyocytes in hypoxia/reoxygenation (H/R). Nitric oxide (NO) donors and endogenous NO could activate autophagy of cardiomyocytes. Activation of heme oxygenase-1 promotes cardiomyocyte tolerance to H/R and enhances autophagy. Hydrogen sulfide increases cardiac tolerance to I/R and inhibits apoptosis and autophagy via mTOR and PI3-kinase activation.

Pharmacological Approaches to Limit Ischemic and Reperfusion Injuries of the Heart: Analysis of Experimental and Clinical Data on P2Y12 Receptor Antagonists.

Ischemic and reperfusion injuries of the heart underlie the pathogenesis of acute myocardial infarction (AMI) and sudden cardiac death. The mortality rate is still high and is 5-7% in patients with ST-segment elevation myocardial infarction. The review is devoted to pharmacological approaches to limitation of ischemic and reperfusion injuries of the heart. The article analyzes experimental evidence and the clinical data on the effects of P2Y12 receptor antagonists on the heart's tolerance to ischemia/reperfusion in animals with coronary artery occlusion and reperfusion and also in patients with AMI. Chronic administration of ticagrelor prevented adverse remodeling of the heart. There is evidence that sphingosine-1-phosphate is the molecule that mediates the infarct-reducing effect of P2Y12 receptor antagonists. It was discussed a role of adenosine in the cardioprotective effect of ticagrelor.

The regulation of necroptosis and perspectives for the development of new drugs preventing ischemic/reperfusion of cardiac injury.

In the last 10 years, mortality from acute myocardial infarction (AMI) has not significantly decreased. This situation is associated with the absence in clinical practice of highly effective drugs capable of preventing the occurrence of reperfusion injury of the heart. Necroptosis inhibitors may become prototypes for the creation of highly effective drugs that increase cardiac tolerance to ischemic/reperfusion (I/R) and reduce the mortality rate in patients with AMI. Necroptosis is involved in I/R cardiac injury and inhibition of RIPK1 or RIPK3 contributes to an increase in cardiac tolerance to I/R. Necroptosis could also be involved in the development of adverse remodeling of the heart. It is unclear whether pre- and postconditioning could inhibit necroptosis of cardiomyocytes and endothelial cells. The role of necroptosis in coronary microvascular obstruction and the no-reflow phenomenon also needs to be studied. MicroRNAs and LncRNAs can regulate necroptotic cell death. Ca2+ overload and reactive oxygen species could be the triggers of necroptosis. Activation of kinases (p38, JNK1, Akt, and mTOR) could promote necroptotic cell death. The interaction of necroptosis, apoptosis, autophagy, ferroptosis, and pyroptosis is discussed. The water-soluble necroptosis inhibitors may be highly effective drugs for treatment of AMI or stroke. It is possible that microRNAs may become the basis for creating drugs for treatment of diseases triggered by I/R of organs.

Production of Reactive Oxygen Species by Epicardial Adipocytes Is Associated with an Increase in Postprandial Glycemia, Postprandial Insulin, and a Decrease in Serum Adiponectin in Patients with Severe Coronary Atherosclerosis.

Purpose. This work investigates the relations between the production of reactive oxygen species (ROS) by epicardial adipose tissue (EAT) adipocytes and parameters of glucose/insulin metabolism, circulating adipokines levels, and severity of coronary atherosclerosis in patients with coronary artery disease (CAD); establishing significant determinants describing changes in ROS EAT in this category of patients. Material and methods. This study included 19 patients (14 men and 5 women, 53−72 y.o., 6 patients with diabetes mellitus type 2; 5 patients with prediabetes), with CAD, who underwent coronary artery bypass graft surgery. EAT adipocytes were isolated by the enzymatic method from intraoperative explants obtained during coronary artery bypass grafting. The size of EAT adipocytes and ROS level were determined. Results. The production of ROS by EAT adipocytes demonstrated a direct correlation with the level of postprandial glycemia (rs = 0.62, p < 0.05), and an inverse correlation with serum adiponectin (rs = −0.50, p = 0.026), but not with general and abdominal obesity, EAT thickness, and dyslipidemia. Regression analysis demonstrated that the increase in ROS of EAT adipocytes occurs due to the interaction of the following factors: postprandial glycemia (ß = 0.95), postprandial insulin (ß = 0.24), and reduced serum adiponectin (ß = −0.20). EAT adipocytes in patients with diabetes and prediabetes manifested higher ROS production than in patients with normoglycemia. Although there was no correlation between the production of ROS by EAT adipocytes and Gensini score in the total group of patients, higher rates of oxidative stress were observed in EAT adipocytes from patients with a Gensini score greater than median Gensini score values (≥70.55 points, Gr.B), compared to patients with less severe coronary atherosclerosis (<70.55 points, Gr.A). Of note, the frequency of patients with diabetes and prediabetes was higher among the patients with the most severe coronary atherosclerosis (Gr.B) than in the Gr.A. Conclusions. Our data have demonstrated for the first time that systemic impairments of glucose/insulin metabolism and a decrease in serum adiponectin are significant independent determinants of oxidative stress intensity in EAT adipocytes in patients with severe coronary atherosclerosis. The possible input of the interplay between oxidative stress in EAT adipocytes and metabolic disturbances to the severity of coronary atherosclerosis requires further investigation.

Reperfusion Cardiac Injury: Receptors and the Signaling Mechanisms.

It has been documented that Ca2+ overload and increased production of reactive oxygen species play a significant role in reperfusion injury (RI) of cardiomyocytes. Ischemia/reperfusion induces cell death as a result of necrosis, necroptosis, apoptosis, and possibly autophagy, pyroptosis and ferroptosis. It has also been demonstrated that the NLRP3 inflammasome is involved in RI of the heart. An increase in adrenergic system activity during the restoration of coronary perfusion negatively affected cardiac resistance to RI. Toll-like receptors are involved in RI of the heart. Angiotensin II and endothelin-1 aggravated ischemic/reperfusion injury of the heart. Activation of neutrophils, monocytes, CD4+ T-cells and platelets contributes to cardiac ischemia/reperfusion injury. Our review outlines the role of these factors in reperfusion cardiac injury.

Left atrial volume changes during exercise stress echocardiography in heart failure and hypertrophic cardiomyopathy.

OBJECTIVE: We aimed to assess feasibility and functional correlates of left atrial volume index (LAVI) changes during exercise stress echocardiography (ESE). METHODS: ESE on a bike or treadmill was performed in 363 patients with heart failure with preserved ejection fraction (HFpEF, n = 173), reduced ejection fraction (HFrEF, n = 59), or hypertrophic cardiomyopathy (HCM, n = 131). The LAVI stress-rest increase ≥6.8 ml/m2 was defined as dilation. RESULTS: LAVI measurements were feasible in 100%. LAVI did not change in HFrEF being at rest 32 (25-45) vs at stress 36 (24-54) ml/m2, P = NS and in HCM at rest 35 (26-48) vs at stress 38 (28-48) ml/m2, P = NS, whereas it decreased in HFpEF from 30 (24-40) to 29 (21-37) ml/m2 at stress, P = 0.007. LA dilation occurred in 107 (30%) patients (27% with treadmill vs 33% with bike ESE, P = NS): 26 with HFpEF (15%), 26 with HFrEF (44%), and 55 with HCM (42%) with P < 0.001 for HFrEF and HCM vs HFpEF. A multivariate analysis revealed as the predictors for LAVI dilation E/e' > 14 at rest with odds ratio (OR) 4.4, LVEF <50% with OR 2.9, and LAVI at rest <35 ml/m2 with OR 2.7. CONCLUSION: The LAVI assessment during ESE was highly feasible and dilation equally frequent with a treadmill or bike. LA dilation was three-fold more frequent in HCM and HFrEF and could be predicted by increased resting E/e' and impaired EF as well as smaller baseline LAVI.

The diagnostic value of SPECT CZT quantitative myocardial blood flow in high-risk patients.

BACKGROUND: The objective of this study was to evaluate the accuracy of global MBF and MFR quantitation performed by myocardial perfusion scintigraphy (MPS) for the detection of multivessel coronary artery disease (CAD). METHODS: 52 CAD patients underwent CZT MPS, with the evaluation of MBF and MFR, followed by invasive coronary angiography (ICA). According to MPS and ICA results, all patients were divided into three groups: (1) non-obstructive CAD and normal MPS scan (control group) (n = 7), (2) one vessel disease (1VD) (n = 16), (3) multivessel disease (MVD) (n = 29). RESULTS: Global absolute MBF and MFR were significantly reduced in MVD patients as compared to those with 1VD [0.93 (IQR 0.76; 1.39) vs 1.94 (1.37; 2.21) mL·min-1·g-1, P = .00012] and [1.4 (IQR 1.02; 1.85) vs 2.3 (1.8; 2.67), P = . 0 004], respectively. The Syntax score correlated with global stress MBF (ρ = - 0.64; P < .0001) and MFR (ρ = - 0.53; P = .0003). ROC analysis showed higher sensitivity and specificity for stress MBF and MFR compared with semiquantitative MPS stress evaluation. Multivariate regression analysis showed that only stress MBF [OR (95% CI) 0.59 (0.42-0.82); P < .0003] was an independent predictor of MVD. CONCLUSIONS: Quantitative myocardial blood flow values assessed with the use of CZT camera may identify high-risk patients, such as those with multivessel disease.

Feasibility and value of two-dimensional volumetric stress echocardiography.

BACKGROUND: Stroke volume response during stress is a major determinant of functional status in heart failure and can be measured by two-dimensional (2-D) volumetric stress echocardiography (SE). The present study hypothesis is that SE may identify mechanisms underlying the change in stroke volume by measuring preload reserve through end-diastolic volume (EDV) and left ventricular contractile reserve (LVCR) with systolic blood pressure and end-systolic volume (ESV). METHODS: We enrolled 4735 patients (age 63.6±11.3 years, 2800 male) referred to SE for known or suspected coronary artery disease (CAD) and/or heart failure (HF) in 21 SE laboratories in 8 countries. In addition to regional wall motion abnormalities (RWMA), force was measured at rest and peak stress as the ratio of systolic blood pressure by cuff sphygmomanometer/ESV by 2D with Simpson's or linear method. Abnormal values of LVCR (peak/rest) based on force were ≤1.10 for dipyridamole (N.=1992 patients) and adenosine (N.=18); ≤2.0 for exercise (N.=2087) or dobutamine (N.=638). RESULTS: Force-based LVCR was obtained in all 4735 patients. Lack of stroke volume increase during stress was due to either abnormal LVCR and/or blunted preload reserve, and 57% of patients with abnormal LVCR nevertheless showed increase in stroke volume. CONCLUSIONS: Volumetric SE is highly feasible with all stresses, and more frequently impaired in presence of ischemic RWMA, absence of viability and reduced coronary flow velocity reserve. It identifies an altered stroke volume response due to reduced preload and/or contractile reserve.

Prognostic value of stress echocardiography assessed by the ABCDE protocol.

AIM: The aim of this study was to assess the prognostic value of ABCDE-SE in a prospective, large scale, multicentre, international, effectiveness study. Stress echocardiography (SE) was recently upgraded to the ABCDE protocol: step A, regional wall motion abnormalities; step B, B lines; step C, left ventricular contractile reserve; step D, Doppler-based coronary flow velocity reserve in left anterior descending coronary artery; and step E, electrocardiogram-based heart rate reserve. METHODS AND RESULTS: From July 2016 to November 2020, we enrolled 3574 all-comers (age 65 ± 11 years, 2070 males, 58%; ejection fraction 60 ± 10%) with known or suspected chronic coronary syndromes referred from 13 certified laboratories. All patients underwent clinically indicated ABCDE-SE. The employed stress modality was exercise (n = 952, with semi-supine bike, n = 887, or treadmill, n = 65 with adenosine for step D) or pharmacological stress (n = 2622, with vasodilator, n = 2151; or dobutamine, n = 471). SE response ranged from score 0 (all steps normal) to score 5 (all steps abnormal). All-cause death was the only endpoint. Rate of abnormal results was 16% for A, 30% for B, 36% for C, 28% for D, and 37% for E steps. During a median follow-up of 21 months (interquartile range: 13-36), 73 deaths occurred. Global X2 was 49.5 considering clinical variables, 50.7 after step A only (P = NS (not significant)) and 80.6 after B-E steps (P < 0.001 vs. step A). Annual mortality rate ranged from 0.4% person-year for score 0 up to 2.7% person-year for score 5. CONCLUSION: ABCDE-SE allows an effective prediction of survival in patients with chronic coronary syndromes.