Cardiovascular testing recovery in Latin America one year into the COVID-19 pandemic: An analysis of data from an international longitudinal survey.

Background: The COVID-19 pandemic disproportionately impacted Latin America (LATAM), significantly disrupting cardiovascular testing. This study evaluated cardiac procedure recovery in LATAM one year after the outbreak. Methods: The International Atomic Energy Agency (IAEA) surveyed 669 centers in 107 countries worldwide, including 135 facilities in 19 LATAM countries, to assess cardiovascular procedure volumes in March 2019, April 2020, and April 2021, and changes in center practices and staffing conditions one year into the COVID-19 pandemic. Findings: LATAM centers reported a 21 % decrease in procedure volumes in April 2021 from pre-pandemic-baseline, vs. a 0 % change in the rest of the world (RoW), and greater volume reductions for almost all procedure types. Centers in Central America and Mexico reported the largest procedure reductions (47 % reduction) compared to the Caribbean (15 %), and South America (14 %, p = 0.01), and this LATAM region was a significant predictor of lower procedure recovery in multivariable regression. More LATAM centers reported reduced salaries and increased layoffs of clinical staff compared to RoW, and LATAM respondents estimated that half of physician and non-physician staff experienced excess psychological stress related to the pandemic, compared to 25 % and 30 % in RoW (p < 0.001). Conclusions: Cardiovascular testing recovery in LATAM trailed behind RoW for most procedure types, with centers in Central America and Mexico reporting the greatest volume reductions. This study found lasting impacts of COVID-19 on cardiovascular care in LATAM and the need for mental health support for LATAM healthcare workers in current and future pandemics.

Current status of nuclear cardiology practice in Latin America and the Caribbean, in the era of multimodality cardiac imaging approach: 2022 update.

Cardiovascular diseases (CVDs) are the leading cause of mortality in Latin America and the Caribbean (LAC), with the risk in men being slightly higher than in women. The coronavirus disease 2019 (COVID-19) pandemic caused a significant reduction in the number of cardiac diagnostic procedures globally and in particular in LAC. Nuclear cardiology is available in the region, but there is variability in terms of existing technology, radiopharmaceuticals, and human resources. In the region, there are 2385 single photon emission computed tomography (SPECT) and 315 PET scanners, Argentina and Brazil have the largest number. There is an increasing number of new technologies such as cadmium-zinc-telluride (CZT) cardiac-dedicated gamma cameras, SPECT/computed tomography (CT), and PET/CT. All countries performed myocardial perfusion imaging studies, mainly gated-SPECT; the rest are multi-gated acquisition, mainly for cardiac toxicity; detection of viability; rest gated SPECT in patients with dilated cardiomyopathy, and bone-avid tracer cardiac scintigraphy for transthyretin cardiac amyloidosis diagnosis. Regarding other non-nuclear cardiac imaging modalities, Argentina, Colombia, and Chile have the highest ratio of CT scanners, while Brazil, Argentina, and Chile show the highest ratio of MRI scanners. The development of nuclear cardiology and other advanced imaging modalities is challenged by the high cost of equipment, lack of equipment maintenance and service, insufficient-specific training both for imaging specialists and referring clinicians, and lack of awareness of cardiologists or other referring physicians on the clinical applications of nuclear cardiology. Another important aspect to consider is the necessity of implementing cardiac imaging multimodality training. A joint work of nuclear medicine specialists, radiologists, cardiologists, and clinicians, in general, is mandatory to achieve this goal. National, regional, and international cooperation including support from scientific professional societies such as the American Society of Nuclear Cardiology and Latin American Association of Biology and Nuclear Medicine Societies, cardiological societies, and organizations such as the International Atomic Energy Agency, and Pan American Health Organization, as well as government commitment are key factors in the overall efforts to tackle the burden of cardiovascular diseases in the region.

Effect of Low-Dose Statins in Addition to Standard Therapy on Brain Perfusion and Neurocognitive Performance in Patients with Major Depressive Disorder.

INTRODUCTION: Major depressive disorder (MDD) is a prevalent condition which has a well-known association with ischemic cardiomyopathy, probably explained by an inflammatory mediator mechanism. Statins, besides reducing cholesterol production, have pleiotropic effects including anti-inflammatory activity. The goal was to evaluate the effect of statins as an addition to standard therapy on mood status, brain perfusion, and neurocognitive performance in MDD. METHODS: We studied 20 MDD patients with brain single-photon emission tomography and Cambridge Neuropsychological Test Automated Battery (CANTAB), half randomized to 10 mg of Rosuvastatin or placebo, in addition to selective serotonin reuptake inhibitors (SSRIs) therapy and being reevaluated 3 months later. The images were compared using Statistical Parametric Mapping; clinical scores (Hamilton Depression Score with 17 items and Beck's Depression Inventory) as well as neurocognitive parameters were applied as covariances (CoV) to estimate regional cerebral blood flow (rCBF) changes with both therapies. RESULTS: Clinical scores decreased in both groups (p = 0.0001); Beck's presented a larger decrease with statins. We observed significantly rCBF changes expressed as significant larger clusters of voxels (p < 0.05) in the pre/subgenual anterior cingulate plus orbitofrontal cortex and a small area in the posterior cingulate gyrus in the statins group, whereas it was not observed with placebo, when using clinical scores as CoV. A similar pattern of rCBF changes was present with emotions recognition, attentional, paired associates learning, spatial planning, and working memory tasks. CONCLUSION: Short-term use of low-dose statins in MDD patients under SSRIs results in important rCBF changes in key mood associated areas to improvement in neurocognitive performance. These findings, even though demonstrated in a small sample, could open a new therapeutic tool in the comprehensive management of this disorder.

Reproducibility of global LV function and dyssynchrony parameters derived from phase analysis of gated myocardial perfusion SPECT: A multicenter comparison with core laboratory setting.

BACKGROUND: Gated myocardial perfusion scintigraphy (GMPS) phase analysis is an important tool to investigate the physiology of left ventricular (LV) dyssynchrony. We aimed to test the performance of GMPS LV function and phase analysis in different clinical settings and on a diverse population. METHODS: This is a post hoc analysis of a prospective, non-randomized, multinational, multicenter cohort study. Clinical evaluation and GMPS prior to cardiac resynchronization therapy (CRT)(baseline) and 6-month post CRT (follow-up) were done. LV end-systolic volume (LVESV), LV end-diastolic volume (LVEDV), LV ejection fraction (LVEF), LV phase standard deviation (LVPSD), and percentage of left ventricle non-viable (PLVNV) were obtained by 10 centers and compared to the core lab. RESULTS: 276 GMPS studies had all data available from individual sites and from core lab. There were no statistically significant differences between all variables except for LVPSD. When subjects with no mechanical dyssynchrony were excluded, LVPSD difference became non-significant. LVESV, LVEF, LVPSD and PLVNV had strong correlation in site against core lab comparison. Bland-Altman plots demonstrated good agreement. CONCLUSIONS: The presented correlation and agreement of LV function and dyssynchrony analysis over different sites with a diverse sample corroborate the strength of GMPS in the management of heart failure in clinical practice.

Clinical and gated SPECT MPI parameters associated with super-response to cardiac resynchronization therapy.

PURPOSE: We sought to evaluate the behavior of cardiac mechanical synchrony as measured by phase SD (PSD) derived from gated MPI SPECT (gSPECT) in patients with super-response after CRT and to evaluate the clinical and imaging characteristics associated with super-response. METHODS: 158 subjects were evaluated with gSPECT before and 6 months after CRT. Patients with an improvement of LVEF > 15% and NYHA class I/II or reduction in LV end-systolic volume > 30% and NYHA class I/II were labeled as super-responders (SR). RESULTS: 34 patients were classified as super-responders (22%) and had lower PSD (32° ± 17°) at 6 months after CRT compared to responders (45° ± 24°) and non-responders 46° ± 28° (P = .02 for both comparisons). Regression analysis identified predictors independently associated with super-response to CRT: absence of previous history of CAD (odds ratio 18.7; P = .002), absence of diabetes mellitus (odds ratio 13; P = .03), and history of hypertension (odds ratio .2; P = .01). CONCLUSION: LV dyssynchrony after CRT implantation, but not at baseline, was significantly better among super-responders compared to non-super-responders. The absence of diabetes, absence of CAD, and history of hypertension were independently associated with super-response after CRT.

Correlación de sincronía de la contracción del ventrículo izquierdo con función sisto-diastólica, masa y excentricidad en diversas afecciones cardíacas mediante un software comercial dedicado de SPECT gatillado / Gated Spect evaluation of ventricular systolic synchrony: correlation with ventricular mass and excentricity in different forms of cardiac disease

INTRODUCCIÓN: Actualmente, hay nuevas herramientas de software disponibles para medir la sincronía de la contracción intraventricular izquierda mediante SPECT de perfusión miocárdica. Esta técnica permite identificar anomalías de la conducción, apoyar la terapia de resincronización en insuficiencia cardíaca refractaria e incluso la detección precoz de isquemia. OBJETIVO: Conocer la correlación de la sincronía de contracción con otros parámetros de disfunción sisto-diastólica ventricular izquierda. MÉTODO: Estudiamos 135 pacientes remitidos para pesquisa o evaluación de enfermedad coronaria conocida mediante SPECT gatillado. La evaluación de la interpretación inicial con programas QPS/QGS® visual y cuantitativo se efectuó a 50 casos con defectos de perfusión transitoria de diversos tamaños (isquemia), 25 de tipo fijo o mixto (infarto) y 60 sin ellos (normal). Los volúmenes telesistólicos oscilaron entre 26 y 458 mL. Se excluyeron casos con arritmias, anomalías de conducción y artefactos (actividad o movimiento extracardiaco). Los SPECT se procesaron retrospectivamente utilizando el programa Emory Synctool®. Del histograma de sincronía de la contracción, el ancho de banda (BW) y la desviación estándar (SD) se correlacionaron con la fracción de eyección (FEVI), volúmenes y excentricidades sistólico / diastólico, masa ventricular izquierda, tasa máxima de llenado (PFR) y tiempo al máximo de llenado (TPFR). RESULTADOS: Los BW y SD del histograma de fase de contracción fueron mayores en el grupo con defectos fijos y mixtos en comparación con los con perfusión normal. Las correlaciones en reposo y post estrés (Spearman) entre SD y BW con FEVI, volúmenes, excentricidad y masa fueron significativas (p <0,0002) salvo TPFR que no fue significativa. CONCLUSIÓN: La sincronía de contracción intraventricular sistólica izquierda medida con SPECT se correlaciona excelentemente con los parámetros funcionales sistólicos y diastólicos, así como con masa y excentricidad en diversas condiciones y tamaños cardíacos.

INTRODUCTION: New software tools are available to measure left intraventricular contraction synchrony by myocardial perfusion SPECT. This technique allows identification of conduction abnormalities, support resynchronization therapy in refractory heart failure and even allows early detection of myocardial ischemia. OBJECTIVE: To determine the correlation of systolic synchrony with other parameters of left ventricular systolic-diastolic dysfunction. METHODS: We studied 135 patients referred for screening or known coronary artery disease evaluation by triggered SPECT. Evaluation of the initial interpretation with visual and quantitative QPS/QGS® programs was performed in 50 patients with transient perfusion defects of various sizes (ischemia), 25 of fixed or mixed type (infarction) and 60 without abnormalities. Telesystolic volumes ranged from 26 to 458 mL. Cases with arrhythmias, conduction abnormalities and artifacts (extracardiac activity or motion) were excluded. SPECT scans were retrospectively processed using the Emory Synctool® software. Histograms of systolic contraction synchrony bandwidth (BW) and standard deviation (SD) were correlated with ejection fraction (LVEF), systolic/diastolic volumes and eccentricities, left ventricular mass, peak filling rate (PFR) and time to maximum filling (TPFR). RESULTS: BW and SD of the contraction pase histogram were higher in the fixed and mixed defect group compared to studies showing normal perfusion. Spearman correlations at rest and poststress between SD and BW with LVEF, volumes, eccentricity and mass were all significant (p<0.0002) except for TPFR. CONCLUSION: Left systolic intraventricular contraction synchrony measured with SPECT presents an excellent correlation with systolic and diastolic functional parameters, as well as with mass and eccentricity in various cardiac conditions and ventricular dimensions.

Cardiomiopatía amiloídea por transtiretina: diagnóstico y manejo en la actualidad / Transthyretin amyloid cardiomyopathy: a review

RESUMEN: La cardiomiopatía amiloide por transtiretina (CATTR) es una enfermedad caracterizada por depósito extracelular de fibrillas amiloides en el miocardio, a partir de transtiretina mal plegada, generando una miocardiopatía restrictiva. Esta proteína mal plegada puede tener origen hereditario o adquirido, siendo más frecuente en adultos mayores. La CA-TTR ha surgido como una causa subdiagnosticada de insuficiencia cardíaca con fracción de eyección preservada (IC FEp). El pilar fundamental para su diagnóstico es la alta sospecha clínica, basada en diversas banderas de alerta ya que la sintomatología que provoca suele ser inespecífica. Como veremos en esta revisión, el diagnóstico puede sustentarse con la cintigrafía ósea, reservando para situaciones particulares la toma de biopsia. Con el advenimiento de nuevas terapias que impactan en la sobrevida de esta enfermedad, el tiempo para realizar el diagnóstico certero y la diferenciación de otras causas de amiloidosis cardíaca como la de cadenas livianas, se ha tornado crucial.

ABSTRACT: Transthyretin amyloid cardiomyopathy (AT-TR-CM) is a disease characterized by extracellular deposition of amyloid fibrils in the myocardium, from misfolded transthyretin, generating a restrictive cardiomyopathy. This misfolded protein may be inherited or acquired, and is more prevalent in elderly patients. ATTR-CM has emerged as an underdiagnosed cause of heart failure with preserved ejection fraction (HF-PEF). The fundamental pillarfor its diagnosis is high clinical suspicion since the symptoms are usually nonspecific. The diagnosis can be made from bone scintigraphy, reserving myocardial biopsy for particular situations. With the advent of new therapies that affect the survival of these patients, a timely diagnosis has become crucial.

Value of intraventricular dyssynchrony assessment by gated-SPECT myocardial perfusion imaging in the management of heart failure patients undergoing cardiac resynchronization therapy (VISION-CRT).

BACKGROUND: Placing the left ventricular (LV) lead in a viable segment with the latest mechanical activation (vSOLA) may be associated with optimal cardiac resynchronization therapy (CRT) response. We assessed the role of gated SPECT myocardial perfusion imaging (gSPECT MPI) in predicting clinical outcomes at 6 months in patients submitted to CRT. METHODS: Ten centers from 8 countries enrolled 195 consecutive patients. All underwent gSPECT MPI before and 6 months after CRT. The procedure was performed as per current guidelines, the operators being unaware of gSPECT MPI results. Regional LV dyssynchrony (Phase SD) and vSOLA were automatically determined using a 17 segment model. The lead was considered on-target if placed in vSOLA. The primary outcome was improvement in ≥1 of the following: ≥1 NYHA class, left ventricular ejection fraction (LVEF) by ≥5%, reduction in end-systolic volume by ≥15%, and ≥5 points in Minnesota Living With Heart Failure Questionnaire (MLHFQ). RESULTS: Sixteen patients died before the follow-up gSPECT MPI. The primary outcome occurred in 152 out of 179 (84.9%) cases. Mean change in LV phase standard deviation (PSD) at 6 months was 10.5°. Baseline dyssynchrony was not associated with the primary outcome. However, change in LV PSD from baseline was associated with the primary outcome (OR 1.04, 95% CI 1.01-1.07, P = .007). Change in LV PSD had an AUC of 0.78 (0.66-0.90) for the primary outcome. Improvement in LV PSD of 4° resulted in the highest positive likelihood ratio of 7.4 for a favorable outcome. In 23% of the patients, the CRT lead was placed in the vSOLA, and in 42% in either this segment or in a segment within 10° of it. On-target lead placement was not significantly associated with the primary outcome (OR 1.53, 95% CI 0.71-3.28). CONCLUSION: LV dyssynchrony improvement by gSPECT MPI, but not on-target lead placement, predicts clinical outcomes in patients undergoing CRT.

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.

Regional Brain Perfusion Is Associated with Endothelial Dysfunction Markers in Major Depressive Disorder.

BACKGROUND: Major depressive disorder (MDD) is an important independent risk factor for cardiovascular disease. Cumulative data suggest that depressive patients exhibit derangement in regional cerebral blood flow (rCBF), although underlying mechanisms remain mostly unknown. Endothelial dysfunction (ED), defined as different forms of abnormal endothelial activity, plays a key role in the pathogenesis of vascular disease. ED is associated with several clinical conditions characterized by high cardiovascular risk. Diverse ED markers have been found in mood disorders. PURPOSE: To evaluate the association between rCBF and peripheral ED markers in MDD patients, at baseline and after selective serotonin receptor inhibitors (SSRIs) therapy. PATIENTS AND METHODS: Twenty-seven untreated unipolar MDD patients in their first episode were evaluated with the Hamilton Depression Rating Scale (HAM-D) and brain perfusion SPECT at baseline and after 2 months of SSRIs. Statistical Parametric Mapping (SPM) was employed to evaluate rCBF; circulating endothelial cells (CECs), plasma soluble intercellular adhesion molecule (sICAM), and high-sensitivity C-reactive protein (hsCRP) were used as independent covariates. RESULTS: Baseline CECs and sICAM were increased in MDD patients compared with matching controls (p = 0.0001) and hsCRP (p = 0.03). HAM-D scores (21 items) and CECs diminished after SSRI therapy in MDD patients (p < 0.0001). There was a significant rCBF decrease, mainly in deep central structures. HAM-D change was associated with rCBF decrease at the left amygdala, right striatum levels, and Brodmann area 25. CEC change was associated with rCBF at deep brain level and sICAM with large rCBF areas at the left caudate and tectum; hsCRP was associated, to a lesser extent, with the left dorsal striatum and mesencephalic tectum. CONCLUSION: ED markers in patients with MDD are associated with significant changes in rCBF which are features of depression. These findings suggest that systemic damage/activation of the endothelium may contribute to the abnormal rCBF observed in MDD patients.

[Predictive value of dipyridamole myocardial perfusion tomography on survival]. / Estratificación de riesgo de muerte a mediano plazo de pacientes evaluados por enfermedad coronaria con SPECT de perfusión miocárdica bajo efecto de dipiridamol.

BACKGROUND: Dipyridamole (DIP) is the most commonly employed pharmacological stressor for myocardial perfusion tomography (SPECT) in patients unable to reach an adequate work load. AIM: To assess the predictive capacity of DIP SPECT on survival. MATERIAL AND METHODS: We included 985 adults aged 66 ±11 years (45% women) with rest and DIP-SPECT. The main indications for the procedure were coronary artery disease (CAD) screening in 66% and known CAD in 33%. Participants were followed up for a median of 65 months (interquartile range 54 to 86 months). During the follow up, 261 deaths were recorded and 98% had a specified cause in their death certificate. RESULTS: Myocardial SPECT was abnormal in 44% of participants. Transient ischemic defects were observed in 34%, fixed defects concordant with infarction in 27% and post-stress systolic dysfunction in 23%. Twenty five percent of deaths were attributable to cardiac or ischemic cause and 22% to cancer. In a bivariate analysis, the hazard ratio (HR) of death of any cause was lower in females and higher in the presence of CAD. The multivariate analysis showed that being older than 46 years increased the HR of death of any cause. In a bivariate analysis, the HR for cardiac death was higher when the myocardial SPECT showed ischemia, necrosis or left ventricular dilation. In the multivariate analysis, post-stress left ventricular systolic function was associated with a lower risk of cardiac death. CONCLUSIONS: An abnormal myocardial SPECT, perfusion abnormalities, left ventricular systolic function or dilation are independent predictors of cardiac death in these participants.

Efecto de la terapia de resincronización ventricular en los parámetros de disfunción endotelial y función sistólica izquierda en pacientes con insuficiencia cardíaca crónica y bloqueo completo de rama izquierda / Endothelial dysfunction, left ventricular function, and chronic heart failure with complete left bundle branch block: effect of resynchronization therapy

Resumen: Introducción: La insuficiencia cardíaca crónica (ICC) es una condición compleja asociada a inflamación sistémica y a disfunción endotelial (DE) cuya patogénesis no es bien comprendida. Objetivo: Evaluar una posible relación entre marcadores de DE periférica con la respuesta a terapia de resincronización ventricular (TRV). Método: 20 pacientes con ICC, QRS ≥120ms y fracción de eyección ventricular izquierda (FEVI) ≤35% se estudiaron pre y 6 meses post-TRV con: Minnesota Living with Heart Failure Questionnaire (MLHFQ); test de marcha (TM-6min); Ecocardiografía-2D y SPECT de perfusión gatillado en reposo; proteína C-reactiva ultra sensible (us-PCR); péptido natriurético cerebral (pro-BNP); células endoteliales circulantes (CEC); moléculas de adhesión soluble vascular (sVCAM) e intercelular (sICAM); interleukina-6 (IL-6) y Factor von Willebrand (FvW). Se clasificaron como respondedores o no a TRV según criterios preestablecidos. Resultados: Promedios basales: pro-BNP 5.290pg/ml; us-PCR 1,7ug/mL; MLHFQ 72; TM-6min 391 metros. Las CEC y sICAM estaban sobre límites normales. Post-TRV, el 50% fue respondedor: 11/20 mejoraron ≥1 clase NYHA y ≥10% del TM-6min; ML-HFQ disminuyó (p<0.0001); FEVI mejoró (p=0.003); volumen final sistólico disminuyó (p=0.008) y también pro-BNP (p=0.03). En los respondedores, las CEC disminuyeron, persistiendo elevadas, sobre lo normal. Existieron correlaciones entre cambios de pro-BNP con TM-6min y entre us-PCR con MLHFQ y FvW (p≤0.004 en todas). Conclusiones: En ICC existe evidencia de significativa DE, expresada por sICAM y CEC, biomarcador periférico sensible. Estas disminuyeron 6 meses post-TRV, persistiendo sobre el límite normal. Otros parámetros funcionales e inflamatorios se correlacionaron en el grupo total, sin diferencias entre grupos respondedores y no respondedores.

Abstract: Introduction: Chronic heart failure (CHF) is a complex condition associated with systemic inflammation and endothelial dysfunction (ED) whose pathogenesis is not well understood. Objective: to evaluate a possible relationship between peripheral ED markers and response to cardiac resynchronization therapy (CRT). Method: 20 patients with CHF, QRS ≥120ms and left ventricular ejection fraction (LVEF) ≤35% were studied before and 6 months post-CRT. Minnesota Living with Heart Failure Questionnaire (MLHFQ); walking test (6min-WT); 2D-echocardiography and gated perfusion SPECT at rest; ultra-sensitive C-reactive protein (us-CRP); brain natriuretic peptide (pro-BNP); circulating endothelial cells (CEC); vascular soluble adhesion (sVCAM) and intercellular adhesion molecules (sICAM); interleukin-6 (IL-6) and von Willebrand Factor (vWF) were measured in all subjects. They were classified as responders or not to CRT, according to pre-established criteria. Results: Basal means: pro-BNP 5,290 pg / ml; us-CRP 1.7 ug/mL; MLHFQ 72; 6min-WT 391 meters. The CEC and IL-6 were above normal limits. Post-CRT, 50% were responders: 11/20 improved ≥1 NYHA class and ≥10% increase in 6min-WT; MLHFQ decreased (p <0.0001); LVEF improved (p = 0.003); final systolic volume decreased (p = 0.008) and also pro-BNP (p= 0.03). In responders CEC decreased, persisting over normal limits. There were correlations between changes of pro-BNP with TM-6min and between us-PCR with MLHFQ and vWF (p≤0.004 in all). Conclusions: In CHF there is evidence of significant ED, expressed by sICAM and CEC, a sensitive peripheral biomarker that decreased 6 months post-CRT although persisting above normal limits. Other functional and inflammatory parameters were correlated in the total group, without differences between responders and non-responders.

Estratificación de riesgo de muerte a mediano plazo de pacientes evaluados por enfermedad coronaria con SPECT de perfusión miocárdica bajo efecto de dipiridamol / Predictive value of dipyridamole myocardial perfusion tomography on survival

Background: Dipyridamole (DIP) is the most commonly employed pharmacological stressor for myocardial perfusion tomography (SPECT) in patients unable to reach an adequate work load. Aim: To assess the predictive capacity of DIP SPECT on survival. Material and Methods: We included 985 adults aged 66 ±11 years (45% women) with rest and DIP-SPECT. The main indications for the procedure were coronary artery disease (CAD) screening in 66% and known CAD in 33%. Participants were followed up for a median of 65 months (interquartile range 54 to 86 months). During the follow up, 261 deaths were recorded and 98% had a specified cause in their death certificate. Results: Myocardial SPECT was abnormal in 44% of participants. Transient ischemic defects were observed in 34%, fixed defects concordant with infarction in 27% and post-stress systolic dysfunction in 23%. Twenty five percent of deaths were attributable to cardiac or ischemic cause and 22% to cancer. In a bivariate analysis, the hazard ratio (HR) of death of any cause was lower in females and higher in the presence of CAD. The multivariate analysis showed that being older than 46 years increased the HR of death of any cause. In a bivariate analysis, the HR for cardiac death was higher when the myocardial SPECT showed ischemia, necrosis or left ventricular dilation. In the multivariate analysis, post-stress left ventricular systolic function was associated with a lower risk of cardiac death. Conclusions: An abnormal myocardial SPECT, perfusion abnormalities, left ventricular systolic function or dilation are independent predictors of cardiac death in these participants.

[False negative spect parathyroid scintigraphy with sestamibi in patients with primary hyperparathyroidism]. / Análisis de falsos negativos en la cintigrafía SPECT de paratiroides con sestamibi en pacientes con hiperparatiroidismo primario sometidos a cirugía entre 2008-2015 en hospital universitario.

BACKGROUND: 99mTc-sestamibi parathyroid SPECT scintigraphy is a useful tool in the pre-operative study of hyperparathyroidism. False negatives (FN) have been reported in 5.7-14% of the examinations. AIM: To characterize 99mTc-sestamibi FN in cases referred for primary hyperparathyroidism (PHP) to a university hospital. MATERIAL AND METHODS: Descriptive retrospective analysis. We included patients with PHP, studied with SPECT scintigraphy, operated at our center between 2008 and 2015. Clinical and surgical data were recorded; biopsies of the FN were blindly reviewed by one pathologist. RESULTS: One hundred twenty one scintigraphies fulfilled the inclusion criteria. Seven (5.8%) were negative and 114 positive. There was no difference in age, sex and PTH levels between FN and true positive scintigraphies. At surgery, one FN case had two hyperplasic glands and two cases had ectopic glands. Pathology reported adenoma in three cases, hyperplasia in three and carcinoma in one. The largest diameter of the lesion was lower in FN (1.3 and 2.1 cm respectively, p = 0.02) and the proportion of adenomas was higher in true positive cases (29% and 75% respectively; p < 0.01). The interval between scintigraphy and parathyroidectomy was greater in FN with a median of 92 days (range 20 days-3.2 years, p < 0.01). The percentage of oxyphilic cells observed was similar in both groups. CONCLUSIONS: FN parathyroid SPECT scintigraphies in PHP are uncommon. They corresponded to lesions under the equipment's resolution limit and resulted in longer time lags between scintigraphy and surgery.

Comprehensive Auditing in Nuclear Medicine Through the International Atomic Energy Agency Quality Management Audits in Nuclear Medicine (QUANUM) Program. Part 1: the QUANUM Program and Methodology.

An effective management system that integrates quality management is essential for a modern nuclear medicine practice. The Nuclear Medicine and Diagnostic Imaging Section of the International Atomic Energy Agency (IAEA) has the mission of supporting nuclear medicine practice in low- and middle-income countries and of helping them introduce it in their health-care system, when not yet present. The experience gathered over several years has shown diversified levels of development and varying degrees of quality of practice, among others because of limited professional networking and limited or no opportunities for exchange of experiences. Those findings triggered the development of a program named Quality Management Audits in Nuclear Medicine (QUANUM), aimed at improving the standards of NM practice in low- and middle-income countries to internationally accepted standards through the introduction of a culture of quality management and systematic auditing programs. QUANUM takes into account the diversity of nuclear medicine services around the world and multidisciplinary contributions to the practice. Those contributions include clinical, technical, radiopharmaceutical, and medical physics procedures. Aspects of radiation safety and patient protection are also integral to the process. Such an approach ensures consistency in providing safe services of superior quality to patients. The level of conformance is assessed using standards based on publications of the IAEA and the International Commission on Radiological Protection, and guidelines from scientific societies such as Society of Nuclear Medicine and Molecular Imaging (SNMMI) and European Association of Nuclear Medicine (EANM). Following QUANUM guidelines and by means of a specific assessment tool developed by the IAEA, auditors, both internal and external, will be able to evaluate the level of conformance. Nonconformances will then be prioritized and recommendations will be provided during an exit briefing. The same tool could then be applied to assess any improvement after corrective actions are taken. This is the first comprehensive audit program in nuclear medicine that helps evaluate managerial aspects, safety of patients and workers, clinical practice, and radiopharmacy, and, above all, keeps them under control all together, with the intention of continuous improvement.

Comprehensive Auditing in Nuclear Medicine Through the International Atomic Energy Agency Quality Management Audits in Nuclear Medicine Program. Part 2: Analysis of Results.

The International Atomic Energy Agency has developed a program, named Quality Management Audits in Nuclear Medicine (QUANUM), to help its Member States to check the status of their nuclear medicine practices and their adherence to international reference standards, covering all aspects of nuclear medicine, including quality assurance/quality control of instrumentation, radiopharmacy (further subdivided into levels 1, 2, and 3, according to complexity of work), radiation safety, clinical applications, as well as managerial aspects. The QUANUM program is based on both internal and external audits and, with specifically developed Excel spreadsheets, it helps assess the level of conformance (LoC) to those previously defined quality standards. According to their level of implementation, the level of conformance to requested standards; 0 (absent) up to 4 (full conformance). Items scored 0, 1, and 2 are considered non-conformance; items scored 3 and 4 are considered conformance. To assess results of the audit missions performed worldwide over the last 8 years, a retrospective analysis has been run on reports from a total of 42 audit missions in 39 centers, three of which had been re-audited. The analysis of all audit reports has shown an overall LoC of 73.9 ± 8.3% (mean ± standard deviation), ranging between 56.6% and 87.9%. The highest LoC has been found in the area of clinical services (83.7% for imaging and 87.9% for therapy), whereas the lowest levels have been found for Radiopharmacy Level 2 (56.6%); Computer Systems and Data Handling (66.6%); and Evaluation of the Quality Management System (67.6%). Prioritization of non-conformances produced a total of 1687 recommendations in the final audit report. Depending on the impact on safety and daily clinical activities, they were further classified as critical (requiring immediate action; n = 276; 16% of the total); major (requiring action in relatively short time, typically from 3 to 6 months; n = 604; 36%); whereas the remaining 807 (48%) were classified as minor, that is, to be addressed whenever possible. The greatest proportion of recommendations has been found in the category "Managerial, Organization and Documentation" (26%); "Staff Radiation Protection and Safety" (17.3%); "Radiopharmaceuticals Preparation, Dispensing and Handling" (15.8%); and "Quality Assurance/Quality Control" and "Management of Equipment and Software" (11.4%). The lowest level of recommendations belongs to the item "Human Resources" (4%). The QUANUM program proved applicable to a wide variety of institutions, from small practices to larger centers with PET/CT and cyclotrons. Clinical services rendered to patients showed a good compliance with international standards, whereas issues related to radiation protection of both staff and patients will require a higher degree of attention. This is a relevant feedback for the International Atomic Energy Agency with regard to the effective translation of safety recommendations into routine practice. Training on drafting and application of standard operating procedures should also be considered a priority.

Análisis de falsos negativos en la cintigrafía SPECT de paratiroides con sestamibi en pacientes con hiperparatiroidismo primario sometidos a cirugía entre 2008-2015 en hospital universitario / False negative spect parathyroid scintigraphy with sestamibi in patients with primary hyperparathyroidism

Background: 99mTc-sestamibi parathyroid SPECT scintigraphy is a useful tool in the pre-operative study of hyperparathyroidism. False negatives (FN) have been reported in 5.7-14% of the examinations. Aim: To characterize 99mTc-sestamibi FN in cases referred for primary hyperparathyroidism (PHP) to a university hospital. Material and Methods: Descriptive retrospective analysis. We included patients with PHP, studied with SPECT scintigraphy, operated at our center between 2008 and 2015. Clinical and surgical data were recorded; biopsies of the FN were blindly reviewed by one pathologist. Results: One hundred twenty one scintigraphies fulfilled the inclusion criteria. Seven (5.8%) were negative and 114 positive. There was no difference in age, sex and PTH levels between FN and true positive scintigraphies. At surgery, one FN case had two hyperplasic glands and two cases had ectopic glands. Pathology reported adenoma in three cases, hyperplasia in three and carcinoma in one. The largest diameter of the lesion was lower in FN (1.3 and 2.1 cm respectively, p = 0.02) and the proportion of adenomas was higher in true positive cases (29% and 75% respectively; p < 0.01). The interval between scintigraphy and parathyroidectomy was greater in FN with a median of 92 days (range 20 days-3.2 years, p < 0.01). The percentage of oxyphilic cells observed was similar in both groups. Conclusions: FN parathyroid SPECT scintigraphies in PHP are uncommon. They corresponded to lesions under the equipment's resolution limit and resulted in longer time lags between scintigraphy and surgery.