Assessment of Left Ventricular Myocardial Fibrosis in Adult Patients With Ebstein Anomaly: A Retrospective Cohort Study Based on Cardiac Magnetic Resonance and Histopathological Samples.

BACKGROUND: The association between Ebstein anomaly and myocardial fibrosis, particularly in the left ventricle, has been controversial. We aimed to assess the prevalence of replacement fibrosis with a focus on the left ventricle (LV) using cardiac magnetic resonance (CMR), make a histopathological association between LV fibrosis and CMR findings, and explore whether LV fibrosis is an independent risk factor for cardiovascular disease mortality using a derived risk score. METHODS: We performed a 12-year (2009-2021) retrospective cohort of adult patients with Ebstein anomaly who underwent CMR. The CMR evaluation included a comprehensive assessment of myocardial fibrosis by late gadolinium enhancement (LGE). Four postmortem samples were obtained from our cohort and stained using Masson trichrome to characterize LV fibrosis. We used Cox-regression analysis to identify and derive a prediction score that associated LV fibrosis with cardiovascular disease mortality. RESULTS: We included 57 adults with Ebstein anomaly (52% men; median age, 29.52 [interquartile range, 21.24-39.17] years), of whom 12 died during follow-up. LGE prevalence by CMR was observed in 52.6% in any chamber; LV-LGE in 29.8%. Histopathological findings revealed a mid-wall pattern with predominantly interstitial fibrosis and minimal replacement fibrosis. LV-LGE was associated with increased risk of cardiovascular disease mortality (hazard ratio, 6.02 [95% CI, 1.22-19.91]) attributable to lateral and mid-wall LV segment involvement. Our mortality score achieved an overall good prediction capacity (R2, 0.435; C statistic, 0.93; Dxy, 0.86). CONCLUSIONS: There is a high prevalence of LV fibrosis replacement in adults with Ebstein anomaly, characterized by specific CMR and histological patterns. Furthermore, LV-LGE fibrosis is an independent predictor of cardiovascular disease mortality, which could be integrated into risk assessment in clinical management.

Positron emission tomography and its role in the assessment of vulnerable plaques in comparison to other imaging modalities.

The diagnosis and management of vulnerable plaques are topics of high interest in the cardiovascular field. Although imaging techniques like computed tomography angiography (MCTA) and ultrasonography (USG) can structurally evaluate atherosclerotic plaques, they are limited in examining internal cellular processes. Positron emission tomography (PET) molecular imaging, on the other hand, can highlight these cellular processes, including inflammation, angiogenesis, and lipid oxidation. Magnetic resonance imaging (MRI) is also a valuable non-invasive imaging technique that can provide detailed anatomical and functional information on the cardiovascular system. In this review, we compare the advantages and drawbacks of MCTA, USG and MRI imaging techniques with PET molecular imaging in evaluating vulnerable plaques. PET imaging allows physicians to measure different pathophysiological events within the plaque using intravenous radiotracers, of which 18F-fluorodeoxyglucose (18F-FDG) is the most validated one. By using 18F-FDG, physicians can understand the formation of the plaque, assess the accumulation of macrophages, and predict major cardiovascular events. However, some limitations exist in using 18F-FDG, including myocardial uptake and low sensitivity in imaging coronary arteries. We also mention other radiotracers that can help in evaluating vulnerable plaques, including 18F-NaF. Although PET imaging is still challenging, it has shown promise in evaluating vulnerable plaques and could be used to intervene in high-risk patients before major cardiovascular events occur.

Assessment of Atypical Cardiovascular Risk Factors Using Single Photon Emission Computed Tomography in Mexican Women.

BACKGROUND: Ischemic heart disease (IHD) is a health care problem in women that increases morbimortality, particularly in developing countries. There is limited information regarding atypical risk factors associated with IHD in Mexican women. AIM: To explore risk factors in women that could contribute to IHD and myocardial dysfunction using the single photon emission computed tomography (SPECT) myocardial perfusion study (MPS). METHODS: We designed a cross-sectional study in which we evaluated atypical and typical risk factors using a clinical questionnaire. We performed a SPECT-MPS to evaluate the presence of ischemia/infarction, decreased left ventricular ejection fraction, systolic dyssynchrony and diastolic function by peak filling rate and time to peak filling rate. RESULTS: 172 women were included, 64 with IHD. Adverse events during pregnancy (premature birth and miscarriage), rheumatoid arthritis, gynecological conditions (menopause and age of first menstruation) and low educational level, together with previously known typical risk factors were associated with infarction or ischemia and ventricular dysfunction. Potential associated factors for systolic dyssynchrony were rheumatoid arthritis (OR: 2.90, 95% CI: 0.95-8.66, p = 0.054) and history of premature birth (OR: 0.13, 95% CI: 0.01-0.66, p <0.01). Although those women with arterial hypertension and smoking shown an increased risk for dyssynchrony, these factors were not statistically significant. Low-educational level (OR 2.16, 95% CI 1.1-4.18, p = 0.019) was associated with decreased peak filling rate. CONCLUSION: The presence of atypical risk factors in women could lead to decreased myocardial function, particularly in women at risk of developing IHD.

Diastolic dyssynchrony assessment by gated myocardial perfusion-SPECT in subjects who underwent cardiac resynchronization therapy.

BACKGROUND: Left ventricular diastolic dyssynchrony (LVDD) can be assessed by gated myocardial perfusion single-photon emission computed tomography (GMP-SPECT). LVDD is an area of interest in subjects who underwent cardiac resynchronization therapy (CRT). The aim of this post hoc analysis was to assess the role of LVDD in subjects with CRT who were followed up at 6-month period. MATERIAL & METHODS: Left ventricular diastolic dyssynchrony was assessed by GMP-SPECT at baseline and after CRT procedure in 160 subjects from 10 different cardiological centers. CRT procedure was performed as per current guidelines. Outcomes were defined as improvement in ≥1 New York Heart Association (NYHA) class, left ventricular ejection fraction (LVEF) by 5%, and reduction in end-systolic volume (ESV) by 15% and 5% points in Minnesota Living with Heart Failure Questionnaire. LVDD was defined as diastolic phase standard deviation ≥40 ± 14°. RESULTS: Improvement in NYHA functional class occurred in 105 (65.6%), LVEF in 74 (46.3%), decrease in ESV in 86 (53.8%), and Minnesota score in 85 (53.1%) cases. Baseline LV diastolic standard deviation was 53.53° ± 20.85 and at follow-up 40.44° ± 26.1283; (P < 0.001). LVDD was not associated with improvement in clinical outcomes at follow-up. CONCLUSION: CRT improves both systolic and diastolic dyssynchrony values at 6-month follow-up. LVDD at baseline is correlated with cardiac functionality at follow-up, but not with overall favorable clinical outcomes.

Can regional training courses reduce interobserver variability?

Cardiovascular disease (CVD) is the principal cause of death worldwide. Noninvasive studies have been used for the evaluation of CVD. Ensuring an accurate diagnosis of CVD requires well-trained and qualified professionals. IAEA has implemented regional training courses which are mainly aimed at professionals from countries with less economic development in order to raise their professional level so that it is in accordance with international standards and thus be able to homogenize the practice of nuclear cardiology globally.

El impacto de la detección de disfunción endotelial en la aterosclerosis: estudio mediante tomografía por emisión de positrones / Impact of the detection of endothelial dysfunction in atherosclerosis: Assessment by positron emission tomography

El endotelio juega un papel importante en la regulación del líquido intracelular, la permeabilidad vascular, en la modulación del tono vascular focal y la angiogénesis. La disfunción endotelial se manifiesta por la pérdida de la capacidad del endotelio de modular el comportamiento fisiológico del lecho vascular y actualmente se considera un marcador pronóstico de la enfermedad arterial coronaria. La relevancia de estudiar la disfunción endotelial radica en que ésta se ha observado en diversas patologías como diabetes mellitas (DM), dislipidemia, hipertensión arterial sistémica, tabaquismo o en enfermedades inmunológicas como síndrome antifosfolípido y lupus eritematoso sistémico. La Tomografía por Emisión de Positrones (PET) es un método no invasivo que permite cuantificar en términos absolutos el flujo miocárdico en reposo, esfuerzo y durante la estimulación adrenérgica, siendo considerado en la actualidad el estándar de oro para valorar la función endotelial. Por lo tanto el PET es una herramienta diagnóstica muy útil en identificar a los pacientes con disfunción endotelial y en evaluar la respuesta a la terapia administrada en enfermedades que se acompañen de ésta. Permitiendo un control óptimo y prevención de eventos adversos de estas enfermedades.

The endothelium plays an important role in the regulation of the intracellular fluid, vascular permeability, and modulation of vascular focal tone and angiogenesis. Endothelial dysfunction is manifested by the loss of the endothelium ability to modulate physiology changes in its vascular bed, and actually it is considered a prognostic marker of coronary artery disease. The relevance of assessing endothelial dysfunction relies in that it has been observed in different pathologies like DM, dyslipidemia, hypertension, tabaquism and in immunologic diseases like antiphospholipid syndrome and systemic lupus. PET is a non invasive method that allows the absolute quantification of myocardial blood flow during rest, stress and adrenergic stimulation, which allows to asses endothelial function. Therefore PET is a useful diagnostic technique to identify patients with endothelial dysfunction, and in the assessment of its response to administered therapy, allowing an optimal control and prevention of secondary adverse events of these diseases.

Importancia de la detección de viabilidad miocárdica: evaluación con tomografía por emisión de positrones con 18F-FDG / Value of the assessment of myocardial viability: evaluation with positron emission tomography 18F-FDG

It used to be thought that the consequences of coronary artery disease were final, and that the prognosis of the patient was limited to the extent of the ventricular dysfunction. This paradigm changed radically when the concept of hibernating myocardium was introduced, which states the existence of tissue that can regain contractile function after being re-vascularized. This introduced a new concept in cardiology: myocardial viability. This work presents a clear example of the importance of detecting myocardial viability in selected patients, due to the impact not only in treatment but in prognosis as well. It is also emphasized that positron emission tomography (PET) is the gold standard method to detect myocardial viability.

[Value of the assessment of myocardial viability: evaluation with positron emission tomography 18F-FDG]. / Importancia de la detección de viabilidad miocárdica: evaluación con tomografía por emisión de positrones con 18F-FDG.

It used to be thought that the consequences of coronary artery disease were final, and that the prognosis of the patient was limited to the extent of the ventricular dysfunction. This paradigm changed radically when the concept of hibernating myocardium was introduced, which states the existence of tissue that can regain contractile function after being re-vascularized. This introduced a new concept in cardiology: myocardial viability. This work presents a clear example of the importance of detecting myocardial viability in selected patients, due to the impact not only in treatment but in prognosis as well. It is also emphasized that positron emission tomography (PET) is the gold standard method to detect myocardial viability.