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Background: Among the other variants, the apical pattern of hypertrophic cardiomyopathy (AHCM) is probably the most important, with possible aneurysmatic evolution. Methods and Results: We analyzed 12 patients with AHCM who underwent [13N]NH3-PET/CT. Regional perfusion, stress global myocardial blood flow (MBF), and transmural perfusion patterns were assessed. To evaluate the LV-MBF distribution, we compared the apex with septum and infero-lateral wall. Furthermore, global stress MBF distribution in AHCM patients was compared with a reference septal HCM cohort. Visual regional perfusion analysis demonstrated an apical hypoperfusion in 10 of 12 patients, without correlation with the stress MBF of the whole LV. Significant differences among stress MBF in apical, in septal, and in the infero-lateral walls were recorded (P <.02). The transmural analysis showed a significant difference among the three segment groups for epicardial (P <.003) as well for endocardial MBF (P <.005). In the post hoc analysis, the apical MBF was significantly lower than in septal and infero-lateral walls in epicardium (P <.005) and significantly lower than the infero-lateral MBF in endocardium (P <.001). Conclusion: In patients with AHCM, more severe apical microvascular impairment was found as compared to patients with classical septal HCM, supporting the suspicion that ischemia could play a role in the future aneurysmatic evolution of AHCM. [ABSTRACT FROM AUTHOR]

Abstract Background The cornerstone of the treatment of patients affected by stable angina is based on drugs administration classified as first (beta-blockers, calcium channel blockers, short acting nitrates) or second line treatment (long-acting nitrates, ivabradine, nicorandil, ranolazine and trimetazidine). However, few data on comparison between different classes of drugs justify that one class of drugs is superior to another. Methods We performed a systematic review of the literature following PRISMA guidelines. Inclusion criteria: i) paper published in English; ii) diagnosis of stable coronary disease; iii) randomized clinical trial; iv) comparison of two anti-angina drugs; v) a sample size >100 patients; vi) a follow-up lasting at least 2 weeks; vii) paper published after 1999, when a meta-analysis of trials comparing beta-blockers, calcium antagonists, and nitrates for stable angina of Heidenreich et al. was published. Outcome: to establish whether the categorization in first and second line antianginal treatment is scientifically supported. Results Eleven trials fulfilled inclusion criteria. The results show that there is a paucity of data comparing the efficacy of antianginal agents. The little data available show that there are not compounds superior to others in terms of improvement in exercise test duration, frequency of anginal attacks, need for sub-lingual nitroglycerin. Conclusion The categorization of antianginal drug in first and second line is not confirmed. Highlights • Medical treatment of stable angina is based on drugs classified as first or second line treatment. • Is the categorization in first and second line antianginal treatment scientifically supported? • We found a paucity of data comparing the efficacy of antianginal agents. • The categorization of antianginal drug in first and second line is not confirmed. [ABSTRACT FROM AUTHOR]

Cardiovascular magnetic resonance (CMR) has evolved from a pioneering research tool to an established noninvasive imaging method for detecting inducible myocardial perfusion deficits. In this consensus document, experts of different imaging techniques summarize the existing body of evidence regarding CMR perfusion as a viable complement to other established noninvasive tools for the assessment of perfusion and discuss the advantages and pitfalls of the technique. A rapid, standardized CMR perfusion protocol is described, which is safe, clinically feasible, and cost-effective for centers with contemporary magnetic resonance equipment. CMR perfusion can be recommended as a routine diagnostic tool to identify inducible myocardial ischemia. [ABSTRACT FROM AUTHOR]

Coronary artery diseases and particularly acute myocardial infarction are the leading causes of mortality and morbidity in western countries. Despite the achievements of the last decades with the advent of double antiplatelet therapy, new antithrombotics and reperfusion strategies (either pharmacological or mechanical), many patients still have adverse cardiovascular events after ST-segment elevation acute myocardial infarction; at least some of these adverse events are related to the no reflow phenomenon that occurs after primary percutaneous coronary intervention. In our review we will discuss the various aspects of this phenomenon. [ABSTRACT FROM AUTHOR]

The growing discoveries coming from clinical and basic research during the past decades have revolutionized our knowledge regarding pathophysiologic mechanisms underlying the atherosclerotic process and its thrombotic complications. The traditional view focusing on the severity of stenosis of atherosclerotic plaque has given way to the evidence that the clinical complications of atherosclerotic vascular disease, particularly the propensity to develop thrombotic complications, are determined mainly by the biological composition of the plaque. This paradigm shift has reinforced the need to move from the sole anatomical assessment toward combined anatomic and functional imaging modalities enabling the molecular and cellular characterization of the disease on top of its structural properties. Together, the progress to identify molecular targets related to plaque vulnerability and the improvement of imaging techniques for the detection of such molecular targets have allowed us to obtain new important pathophysiological information. This might allow better patient stratification for the identification of subjects at high risk to develop premature atherosclerosis who might need an aggressive therapeutic approach. Nuclear techniques, magnetic resonance imaging, computed tomography angiography, and contrast-enhanced ultrasound represent the currently available non-invasive imaging modalities for molecular imaging which can provide different and complementary insights into the biological features of the atherosclerotic process. This clinical review will discuss the evidence and potential translational applications of the individual imaging techniques particularly concerning their ability to detect the main atherosclerotic features related to plaque vulnerability, such as plaque inflammation and intertwined neovascularization. [ABSTRACT FROM AUTHOR]

The original article can be found online at https://doi.org/10.1007/s12350-022-02911-y. The correct address is: Raffaella Calabretta, Division of Nuclear Medicine, Department of Biomedical Imaging and Image-guided Therapy, Medical University of Vienna, Vienna, Austria. [Extracted from the article]

Objectives: The aim of this study was to ascertain whether coronary microvascular dysfunction (CMD) and inflammation are related in cardiac syndrome X (CSX). Background: CMD can lead to CSX, defined as typical angina and transient myocardial ischemia despite normal coronary arteriograms. Inflammation has been suggested to play a role in the pathogenesis of myocardial ischemia in CSX. Methods: We assessed 21 CSX patients (age 52 ± 10 years; 17 women) without traditional cardiovascular risk factors and 21 matched apparently healthy control subjects. Positron emission tomography was used to measure myocardial blood flow (MBF) and coronary flow reserve (CFR) in response to intravenous adenosine, whereas high-sensitivity C-reactive protein (CRP) was measured to assess inflammation. Patients were subdivided a priori into 2 groups according to CRP concentrations at study entry (i.e., ≤3 or >3 mg/l). Results: There were no differences in resting (1.20 ± 0.23 ml/min/g vs. 1.14 ± 0.20 ml/min/g; p = 0.32) or hyperemic MBF (3.28 ± 1.02 ml/min/g vs. 3.68 ± 0.89 ml/min/g; p = 0.18) between CSX patients and the control group, whereas CFR was mildly reduced in CSX patients compared with the control group (2.77 ± 0.80 vs. 3.38 ± 0.80; p = 0.02). Patients with CRP >3 mg/l had more severe impairment of CFR (2.14 ± 0.33 vs. 3.16 ± 0.76; p = 0.001) and more ischemic electrocardiographic changes during adenosine administration than patients with lower CRP, and a negative correlation between CRP levels and CFR (r = −0.49, p = 0.02) was found in CSX patients. Conclusions: CSX patients with elevated CRP levels had a significantly reduced CFR compared with the control group, which is indicative of CMD. Our study thus suggests a role for inflammation in the modulation of coronary microvascular responses in patients with CSX. [Copyright &y& Elsevier]

Cardiac sympathetic imaging with meta-iodobenzylguanidine (mIBG) is a noninvasive tool to risk stratify patients with heart failure (HF). In patients with ischemic and nonischemic cardiomyopathy, cardiac mIBG activity is a very powerful predictor of survival. Cardiac sympathetic imaging can help in understanding how sympathetic overactivity exerts its deleterious actions, which may result in better therapy and outcome for patients with HF. [Copyright &y& Elsevier]

Background: ADMIRE-HF (AdreView Myocardial Imaging for Risk Evaluation in Heart Failure) consists of two identical prospective open-label, multicenter, phase 3 studies (MBG311 and MBG312) evaluating the prognostic usefulness of (123)I-mIBG scintigraphy for identifying subjects with heart failure who will experience a major adverse cardiac event.Methods: Subjects with NYHA class II and III heart failure and left ventricular ejection fraction < or = 35% were eligible for the trials. Subjects underwent planar and SPECT (123)I-mIBG myocardial imaging, as well as echocardiography and gated SPECT (99m)Tc-tetrofosmin myocardial perfusion imaging. Subjects are then monitored on a regular basis for 2 years. Time to first occurrence of one of the following--NYHA class progression; potentially life-threatening arrhythmic event (including ICD discharge); or cardiac death, as verified by an independent adjudication panel---will be analyzed in comparison to quantitative parameters derived from (123)I-mIBG imaging. The primary efficacy analysis will employ the heart/mediastinum ratio on 4-hour delayed planar imaging, while secondary efficacy analyses will examine quantitative results from both planar and SPECT (123)I-mIBG images, as well as from (99m)Tc-tetrofosmin SPECT and echocardiography.Conclusion: The results of the ADMIRE-HF trials will provide prospective validation of the potential role of (123)I-mIBG scintigraphy in assessing prognosis and developing management strategies for patients with heart failure. [ABSTRACT FROM AUTHOR]

Background: Atrial fibrillation (AF) and coronary microvascular dysfunction (CMD) are common in hypertrophic cardiomyopathy (HCM), but whether they are associated is unclear. We assessed the relationship between AF and CMD in HCM. Methods and Results: Global hyperemic myocardial blood flow (hMBF) was measured in 95 HCM patients (16 with, 79 without paroxysmal or chronic AF) by N-13 ammonia positron emission tomography (PET) after dipyridamole infusion. AF patients were older (50.5 ± 13.4 vs. 38.7 ± 14.9 years, P < .0005), had larger left atrial diameter (49.8 ± 7.4 vs 38.6 ± 5.7 mm, P < .00001), and left ventricular end-systolic diameter (30.4 ± 6.7 vs 25.5 ± 5.3 mm, P < .005) compared with those in stable sinus rhythm. In patients with AF, hMBF was significantly lower (1.23 ± 0.44 vs 1.87 ± 0.90 mL/min/g, P < 0.0001). In multivariate logistic regression analysis, hMBF, left atrial diameter, and age were independently associated with AF ( P < .05 for all). Conclusions: HCM patients with paroxysmal or chronic AF have lower hMBF than those in stable sinus rhythm. The association between CMD and AF is independent of other known predictors of AF, suggesting a causal link between these two features. [ABSTRACT FROM AUTHOR]

Background: ADMIRE-HF (AdreView Myocardial Imaging for Risk Evaluation in Heart Failure) consists of two identical prospective open-label, multicenter, phase 3 studies (MBG311 and MBG312) evaluating the prognostic usefulness of I- mIBG scintigraphy for identifying subjects with heart failure who will experience a major adverse cardiac event. Methods: Subjects with NYHA class II and III heart failure and left ventricular ejection fraction ≤35% were eligible for the trials. Subjects underwent planar and SPECT I- mIBG myocardial imaging, as well as echocardiography and gated SPECT Tc-tetrofosmin myocardial perfusion imaging. Subjects are then monitored on a regular basis for 2 years. Time to first occurrence of one of the following-NYHA class progression; potentially life-threatening arrhythmic event (including ICD discharge); or cardiac death, as verified by an independent adjudication panel-will be analyzed in comparison to quantitative parameters derived from I- mIBG imaging. The primary efficacy analysis will employ the heart/mediastinum ratio on 4-hour delayed planar imaging, while secondary efficacy analyses will examine quantitative results from both planar and SPECT I- mIBG images, as well as from Tc-tetrofosmin SPECT and echocardiography. Conclusion: The results of the ADMIRE-HF trials will provide prospective validation of the potential role of I- mIBG scintigraphy in assessing prognosis and developing management strategies for patients with heart failure. [ABSTRACT FROM AUTHOR]

Background: Mechanistic differences between pharmacologic stressors may offer different clinical benefits. Therefore the effects of dobutamine and adenosine on absolute myocardial blood flow (MBF) and coronary flow reserve (CFR) were compared. Methods and Results: We divided 36 patients (mean age, 61 ± 8 years) with coronary artery disease into 2 groups based on stenosis severity as follows: greater than 50% but less than 75% (n = 16) and greater than 75% (n = 20). In addition, 18 normal volunteers (mean age, 46 ± 7 years) served as control subjects. Groups of equal sizes received either dobutamine or adenosine. MBF at rest and peak MBF were measured by use of positron emission tomography in territories subtended by the stenosis (ischemic) and remote myocardium (remote), whereas left ventricular MBF was used in control subjects. CFR was calculated as peak MBF divided by MBF at rest. CFR was significantly greater with adenosine than with dobutamine stress in control subjects and remote CFR. Ischemic CFR was blunted to a similar degree with each stressor. Therefore adenosine achieved flow heterogeneity across all coronary stenosis severities greater than 50%. However, dobutamine achieved flow heterogeneity only in the presence of a severe coronary stenosis greater than 75% despite provoking a greater ischemic stimulus. Conclusion: Adenosine stress demonstrated a higher sensitivity and dobutamine demonstrated a higher specificity with quantitative perfusion imaging. Therefore adenosine is superior for diagnostic perfusion imaging, whereas dobutamine is better suited in combination with visual imaging and in the functional assessment of a known coronary stenosis. [Copyright &y& Elsevier]