Assessment of extra-parenchymal lung involvement in asymptomatic cancer patients with COVID-19 pneumonia detected on 18F-FDG PET-CT studies.

BACKGROUND: Lung involvement in patients with coronavirus disease 2019 (COVID-19) undergoing PET-CT has been previously reported. However, FDG uptake outside lung parenchyma was poorly characterized in detail. We evaluated the extra-parenchymal lung involvement in asymptomatic cancer patients with COVID-19 pneumonia through 18F-FDG PET-CT. METHODS: A total of 1079 oncologic 18F-FDG PET-CT were performed between February 2 and May 18, 2020. Confirmed COVID-19 pneumonia was defined as characteristic ground-glass bilateral CT infiltrates and positive genetic/serologic tests. Nonmetastatic extra-parenchymal lung PET-CT findings were evaluated through qualitative (visual), quantitative (measurements on CT), and semiquantitative (maximum standardized uptake value: SUVmax on PET) interpretation. Clinical data, blood tests, and PET-CT results were compared between patients with and without COVID-19 pneumonia. RESULTS: A total of 23 18F-FDG PET-CT scans with pulmonary infiltrates suggestive of COVID-19 and available laboratory data were included: 14 positive (cases) and 9 negative (controls) for COVID-19 infection, representing a low prevalence of COVID-19 pneumonia (1.3%). Serum lactate dehydrogenase and D-dimers tended to be increased in COVID-19 cases. Extra-parenchymal lung findings were found in 42.9% of patients with COVID-19, most frequently as mediastinal and hilar nodes with 18F-FDG uptake (35.7%), followed by incidental pulmonary embolism in two patients (14.3%). In the control group, extra-pulmonary findings were observed in a single patient (11.1%) with 18F-FDG uptake located to mediastinal, hilar, and cervical nodes. Nasopharyngeal and hepatic SUVmax were similar in both groups. CONCLUSION: In cancer patients with asymptomatic COVID-19 pneumonia, 18F-FDG PET-CT findings are more frequently limited to thoracic structures, suggesting that an early and silent distant involvement is very rare. Pulmonary embolism is a frequent and potentially severe finding raising special concern. PET-CT can provide new pathogenic insights about this novel disease.

Brugada phenocopy secondary to extensive inferior wall ischemia induced by coronary steal effect.

The diagnosis of Brugada syndrome is usually made with a typical ECG pattern. However, different disorders can emulate this pattern (Brugada phenocopies). Pathophysiologic mechanisms underlying this phenomenon remain controversial. We describe the development of type-1 Brugada ECG pattern associated with extensive coronary steal effect during myocardial perfusion scintigraphy. Proximal occlusion of the right coronary artery and severe proximal stenosis in distally occluded left circumflex artery were confirmed by coronary angiogram. Brugada ECG pattern can be a reversible sign associated with inferior left ventricular and right ventricular ischemia. Its presence during acute ischemia deserves appropriate risk stratification.

[Ischemic T wave distortion associated with vasodilator-stress myocardial perfusion imaging]. / Distorsión morfológica isquémica de la onda T en la centellografía de perfusión miocárdica con estrés vasodilatador.

The protocols using vasodilators to induce ischemia on myocardial perfusion scintigraphy have shown a high diagnostic accuracy and a very low incidence of serious complications. However, the physiological significance and diagnostic value of various electrocardiographic changes associated with vasodilator stress has not been deeply evaluated beyond the ST-segment. Five clinical cases presenting morphological distortion of the T-wave in electrocardiographic chest leads associated with varying degrees of perfusion defects are described, discussing potential contributions of these changes to the diagnosis and quantification of myocardial ischemia in imaging studies using vasodilator stress.

Brugada Phenocopy as a Dynamic Electrocardiographic Pattern during Acute Anterior Myocardial Infarction.

Brugada phenocopies represent some unusual clinical cases with identical characteristics to Brugada syndrome (BrS) elicited by various clinical circumstances. We report the case of a woman exhibiting "Brugada Phenocopy" during an acute anterior myocardial infarction, highlighting differential diagnosis with true BrS and discussing possible mechanisms underlying its dynamic ECG pattern.

[Left ventricular dyssynchrony in prolonged septal stimulation]. / Disincronía ventricular izquierda en la estimulación septal prolongada.

Pacemaker stimulation is associated with unpredictable severe cardiac events. We evaluated left ventricular mechanical dyssynchrony (LVMD) during prolonged septal right ventricular pacing. We performed 99mTc-MIBI gated-SPECT and phase analysis in 6 patients with pacemakers implanted at least one year before scintigraphy due to advanced atrioventricular block. Using V-Sync of Emory Cardiac Toolbox we obtained phase bandwidth (PBW) and standard deviation (PSD) from rest phase histogram. Clinical variables, QRS duration, rate and mode of pacing in septal right ventricle wall, chamber diameters, presence and extension of myocardial scar and ischemia and rest LVEF were recorded. Prolonged septal endocardial pacing is associated with marked LVMD, even when systolic function was preserved. More severe dyssynchrony was found in patients with impaired LVEF, higher left ventricle diameters, extensive infarct or severe ischemia than in patients with preserved LVEF (PBW: 177.3o vs. 88.3o; PSD: 53.1o vs. 33.8o). In the patients with ischemic heart disease and pacemaker, gated-SPECT phase analysis is a valid and potentially useful technique to evaluate LMVD associated with myocardial scar and to decide the upgrading to biventricular pacing mode.

Incidental Findings Suggestive of COVID-19 Pneumonia in Oncologic Patients Undergoing 18F-FDG PET/CT Studies: Association Between Metabolic and Structural Lung Changes.

Although the novel coronavirus disease 2019 (COVID-19) can present as nonspecific clinical forms, subclinical cases represent an important route of transmission and a significant source of mortality, mainly in high-risk subpopulations such as cancer patients. A deeper knowledge of the metabolic shift in cells infected with severe acute respiratory syndrome coronavirus 2 could provide new insights about its pathogenic and host response and help to diagnose pulmonary involvement. We explored the potential added diagnostic value of 18F-FDG PET/CT scans in asymptomatic cancer patients with suspected COVID-19 pneumonia by investigating the association between metabolic and structural changes in the lung parenchyma. Methods:18F-FDG PET/CT studies acquired between February 19 and May 29, 2020, were reviewed to identify those cancer patients with incidental findings suggestive of COVID-19 pneumonia. PET studies were interpreted through qualitative (visual) and semiquantitative (measurement of SUVmax) analysis evaluating lung findings. Several characteristic signs of COVID-19 pneumonia on CT were described as COVID-19 Reporting and Data System (CO-RADS) categories (1-6). After comparing the SUVmax of pulmonary infiltrates among different CO-RADS categories, we explored the best potential cutoffs for pulmonary SUVmax against CO-RADS categories as the gold standard result to eliminate the possibility that the diagnosis of COVID-19 pneumonia exists. Results: On multimodal PET/CT imaging, CT signs classified as CO-RADS category 5 or 6 were found in 16 of 41 (39%) oncologic patients. SUVmax was higher in patients with categories 5 and 6 than in patients with category 4 (6.17 ± 0.82 vs. 3.78 ± 0.50, P = 0.04) or categories 2 and 3 (3.59 ± 0.41, P = 0.01). A specificity of 93.8% (95% CI, 71.7%-99.7%) and an accuracy of 92.9% were obtained when combining a CO-RADS score of 5 or 6 with an SUVmax of 2.45 in pulmonary infiltrates. Conclusion: In asymptomatic cancer patients, the metabolic activity in lung infiltrates is closely associated with several combined tomographic changes characteristic of COVID-19 pneumonia. Multimodal 18F-FDG PET/CT imaging could provide additional information during early diagnosis in selected predisposed patients during the pandemic. The prognostic implications of simultaneous radiologic and molecular findings in cancer patients and other subpopulations at high risk for COVID-19 pneumonia deserve further evaluation in prospective research.

Endovascular treatment of coronary subclavian steal syndrome: a case series highlighting the diagnostic usefulness of a multimodality imaging approach.

BACKGROUND: Coronary subclavian steal syndrome (CSSS) is an uncommon complication observed in patients after coronary artery bypass surgery with left internal mammary artery (LIMA) grafts. It is defined as coronary ischaemia due to reversal flow from the LIMA to the left subclavian artery (SA) when a proximal left SA stenosis is present. In practice, the entire clinical spectrum of ischaemic heart disease, ranging from asymptomatic patients to acute myocardial infarction, may be encountered. CASE SUMMARY: Three cases of CSSS recently detected at our hospital are being described. Two patients presented with an acute coronary syndrome, so diagnosis was suspected based on coronary angiography findings, as retrograde blood flow from LIMA to the distal SA was present. Myocardial ischaemia was documented by myocardial perfusion scintigraphy in one case. The third patient was asymptomatic and CSSS was suspected during physical examination and confirmed by computed tomography (CT). Endovascular intervention with balloon-expandable stent implantation of the stenotic SA was performed by vascular surgeons in all patients. No periprocedural complications occurred, and complete resolution of symptoms was achieved. DISCUSSION: In CSSS, subclavian angiography is the standard diagnostic test. However, other diagnostic techniques may be valuable to better clarify this challenging diagnosis. In the herein small series, the usefulness of a multimodality imaging approach including Doppler ultrasound, myocardial perfusion scintigraphy, and CT is well demonstrated. Furthermore, this study endorses the safety and utility of endovascular treatment in different clinical scenarios, including asymptomatic patients.

Clinical relevance of incidental focal breast uptake on fluorine-18 fluorodeoxyglucose PET/computed tomography studies: an experience in a high-load center of Spain.

AIM: We aimed to determine the frequency and clinical significance of breast incidental uptake (BIU) detected through fluorine-18 fluorodeoxyglucose (18F-FDG) PET/computed tomography (CT) in a single, high-load center. PATIENTS AND METHODS: In this retrospective study, we analyzed a total of 13 763 PET/CT studies performed from January 2017 to January 2020. After excluding 3148 scans, the maximum standardized uptake value (SUVmax) and maximum diameter (cm) of each BIU were measured. Clinical management, ultrasound/mammography and pathology reports were analyzed. RESULTS: We found BIU in 27 scans of 26 patients (0.3% of the studies). Mean age was 62.2 years and 88.5% were women; 84.6% underwent PET/CT for oncological indications. Ultrasound/mammography was consequently performed in 23 patients (88.5%), and histological correlations were available for Breast Imaging Reporting and Data System categories 4 and 5. Finally, lesions were benign in 14 patients (60.9%; two of them with low/intermediate risk of malignancy) and malignant in nine patients (39.1%). The remaining three patients had no ultrasound/mammography reports. Mean SUVmax of benign and malignant lesions were 2.6 ± 1.4 and 5.8 ± 3.5, respectively (P = 0.002). Considering a SUVmax cut-off value of 4.0, the sensitivity and specificity for differentiating benign vs. malignant lesions were 67 and 93%, respectively. Benign lesions were smaller than malignant in CT (maximum diameter:1.3 ± 0.5 cm vs. 2.0 ± 1.0 cm, P = 0.02). CONCLUSION: Although BIU detected by 18F-FDG PET/CT is infrequently found, the risk of malignancy remains very high (39.1%). Both SUVmax and maximum diameter were greater in malignant than in benign lesions. An exhaustive study with ultrasound/mammography and selective histopathological correlation is mandatory after BIU findings, even in small lesions.

Incidental and simultaneous finding of pulmonary thrombus and COVID-19 pneumonia in a cancer patient derived to 18F-FDG PET/CT. New pathophysiological insights from hybrid imaging.

Cancer patients require a careful clinical follow-up during the coronavirus disease 2019 (COVID-19) pandemic. Although hybrid fluorine-18 Fluorodeoxyglucose (18F-FDG) positron emission tomography-computed tomography (PET/CT) is not routinely used in the management of COVID-19 patients, it could play a complementary role of other laboratory and radiological data in selected cases. We describe an asymptomatic cancer patient derived to 18F-FDGPET/CT with simultaneous findings of COVID-19 pneumonia and pulmonary thrombus, discussing its possible mechanisms and prognostic implications.

Perfil de liberación de biomarcadores miocárdicos en pacientes con enfermedades hemato-oncológicas que reciben trasplante de progenitores hematopoyéticos / Profile or myocardial biomarkers release in patients with hemato-oncological diseases who receive hematopoietic stem cell transplantation / Perfil de liberação de biomarcadores miocárdicos em pacientes com doenças hemato-oncológicas que recebem transplante de células-tronco hematopoéticas

Introducción: las enfermedades cardiovasculares (CV) son la primera causa de muerte en quienes sobreviven al cáncer. Aunque el trasplante de progenitores hematopoyéticos (TPH) se asocia con grados variables de cardiotoxicidad, estas complicaciones han sido escasamente caracterizadas. Objetivo: analizar el perfil de liberación de biomarcadores miocárdicos como potenciales indicadores subclínicos de cardiotoxicidad en pacientes sometidos a TPH. Material y método: estudio descriptivo, analítico, prospectivo transversal y unicéntrico, reclutando pacientes derivados a la policlínica de cardio-oncología, con indicación de TPH en octubre de 2018-marzo de 2020. Se realizaron controles clínicos, ECG, bioquímicos (troponina I TnI y péptido natriurético del tipo BBNP) e imagenológicos según algoritmo de seguimiento. Las variables discretas se presentan como n (%) y las continuas mediante media ± DE o mediana RIQ. Los valores evolutivos de biomarcadores séricos se compararon mediante test de Friedman. La fracciónde eyección del VI (FEVI) basal se comparó con la de los 3 meses del TPH mediante test de Wilcoxon. Resultados: se incluyeron 19 pacientes, 37% mujeres, de 43,8 ± 15,7 años. No se detectaron modificaciones significativas de la FEVI en los controles evolutivos. En ningún caso se observó aumento de la TnI. Los valores de BNP aumentaron en 6 pacientes (32%), con diferencias significativas al mes postrasplante (basal: 13,6 1;6,1-30,9 vs. primer mes: 38,9 16,3-120,0 pg/ml, p = 0,036); con una mayor elevación en aquellos pacientes que recibieron antimetabolitos vs. otros fármacos (basal: 13,6 1;6,1-30,9 vs. al primer mes: 67,0 ;21,3-174,9 pg/ml, p = 0,039). El aumento de BNP no se asoció con el riesgo CV. Conclusión: la liberación de BNP posterior al TPH es un fenómeno frecuente (32% de los pacientes), alcanza un máximo al mes, independientemente de la FEVI. El subgrupo de pacientes que recibió antimetabolitos presentó una mayor liberación precoz de BNP.

Introduction: cardiovascular (CV) diseases are the leading cause of death in those who survive cancer. Although hematopoietic stem cell transplantation (HSCT) is associated with diverse grades of cardiotoxicity, these complications have been poorly characterized. Objective: to analyze the release profile of myocardial biomarkers as a potential subclinical marker of cardiotoxicity in patients undergoing HSCT. Material and method: descriptive, analytical, prospective, cross-sectional, single-center study, recruiting patients referred to the cardio-oncology polyclinic, with indication for HSCT in October 2018-March 2020. Clinical, ECG, biochemical and imaging controls were performed according to the algorithm of follow-up. The evolutionary values of serum biomarkers were compared using the Friedman test. Baseline LVEF was compared with that of 3 months after HSCT using the Wilcoxon test. Results: 19 patients were included, 37% women, aged 43.8 ± 15.7 years. No changes in LVEF were detected. In no case was an increase in TnI observed. BNP values increased in 6 patients (32%), with significant differences one month after transplantation (baseline: 13.6 ;6.1-30.9 vs. first month: 38.9 ;16.3-120.0, p = 0.036), detecting a greater elevation in those patients who received antimetabolites vs. other rugs (baseline: 13.6 ;6.1-30.9 vs. at the first month: 67.0 21.3-174.0, p = 0.039). The increase in BNP was not associated with CV risk. Conclusion: BNP release after HSCT is frequent (32% of our patients), reaching a maximum at one month, regardless of LVEF. The subgroup of patients who received antimetabolites had a greater early release of BNP.

Introdução: as doenças cardiovasculares (CV) são a principal causa de morte em pessoas que sobrevivem ao câncer. Embora o transplante de células-tronco hematopoéticas (TCTH) esteja associado à diverso grado de cardiotoxicidade, essas complicações têm sido mal caracterizadas. Objetivo: analisar o perfil de liberação de biomarcadores miocárdicos como potenciais marcadores subclínicos de cardiotoxicidade em pacientes submetidos ao TCTH. Material e método: estudo descritivo, analítico, prospectivo, transversal, unicéntrico, com recrutamento de pacientes encaminhados à policlínica de cardio-oncologia, com indicação de TCTH de outubro de 2018 a março de 2020. Foram realizados controles clínicos, eletrocardiográficos, bioquímicos e de imagem de acordo com o algoritmo de acompanhamento. Os valores evolutivos dos biomarcadores séricos foram comparados pelo teste de Friedman. A FEVE basal foi comparada com a de 3 meses após o TCTH usando o teste de Wilcoxon. Resultados: foram incluídos 19 pacientes, 37% mulheres, com idade de 43,8 ± 15,7 anos. Nenhuma mudança na LVEF foi detectada. Em nenhum caso foi observado um aumento de TnI. Os valores de BNP aumentaram um mês após o transplante (linha de base: 13,6 6,1-30,9; vs. primeiro mês: 38,9 16,3-120,0, p = 0,036), se detectou uma maior elevação nos pacientes que receberam antimetabólitos vs. outros medicamentos (linha de base: 13,6 ;6,1-30,9; vs. no primeiro mês: 67,0 ;21,3-174,0;, p = 0,039). O aumento do BNP não foi associado ao risco CV. Conclusão: a liberação do BNP após o TCTH é frequente (32% de nossos pacientes), podendo chegar a no máximo um mês, independente da FEVE. O subgrupo de pacientes que recebeu antimetabólitos apresentou maior liberação precoce de BNP.

Atrial Arrhythmias and Scintigraphic "D-shape" Sign in Pulmonary Artery Hypertension.

Pulmonary hypertension significantly changes biventricular anatomy and physiology, frequently evolving to clinical deterioration and right ventricular failure. The case of a woman developing atrial arrhythmias complicating dipyridamole stress in concomitance with scintigraphic "D-shaped" left ventricle is briefly reported. Although rare, our finding may suggest that nonselective vasodilators should be used with caution in this clinical setting.

Unusual Dipyridamole-induced Aberrant Conduction in the Absence of Myocardial Ischemia.

We report two patients referred to 2 day stress-rest single photon emission computed tomography for diagnosis of ischemia who elicited a transient left bundle branch block during dipyridamole intravenous infusion. The conduction disturbance disappeared after aminophyline infusion and became permanent during follow-up. Possible mechanisms underlying this unusual phenomenon in the absence of myocardial ischemia are discussed.

[Effects of prolonged endocardial stimulation on left ventricular mechanical synchrony. A pilot study applying gated-SPECT phase analysis. Endocardial stimulation and dyssynchrony]. / Efectos de la estimulación endocárdica prolongada sobre la sincronía mecánica ventricular izquierda. Ensayo piloto aplicando análisis de fase por tomografía computada por emisión de fotón único gatillada. Estimulación prolongada y disincronía mecánica.

OBJETIVE: To evaluate left ventricular mechanical dyssynchrony (LVMD) associated with prolonged right ventricular pacing through an innovative imaging technique as a pilot study in Uruguay. METHODS: A 99mTc-MIBI gated-SPECT and phase analysis was performed in 12 patients with pace-makers implanted at least one year before scintigraphy, due to advanced atrioventricular block. Clinical data, QRS duration, rate, mode and site of pacing in right ventricle, chamber diameters, presence and extension of myocardial scar and ischaemia, as well as LVEF at rest, were recorded. Using V-Sync of Emory Cardiac Toolbox, a standard deviation (PSD) and bandwidth (PBW) from rest phase histogram was obtained and these indexes were compared with controls in the subgroups of patients with LVEF≥50% and <50%. RESULTS: Patients with prolonged RV endocardial pacing exhibited marked LVMD. More severe dyssynchrony was found in patients with impaired LVEF than in patients with preserved LVEF (PSD: 46.67o vs. 26.81o, P<.05; PBW: 144.33o vs. 77.41o, P<.05). Higher left ventricle diameters, extensive infarct, or significant ischaemia were found in patients with impaired LVEF. CONCLUSIONS: Chronic right ventricular pacing was invariably associated with LVMD, even when systolic function was preserved. Phase analysis could be a potentially useful technique to evaluate LMVD associated with myocardial scar in patients with pacemakers, and to decide promptly the upgrading to biventricular pacing.

Isquemia inducida por fluoropirimidinas en un paciente con cáncer de esófago y enfermedad coronaria / Fluoropyrimidine-induced ischemia in a patient with oesophageal cancer

Resumen Los grandes avances terapéuticos de las últimas décadas han prolongado la sobrevida de muchos pacientes con cáncer. Sin embargo, esta mejoría se ha logrado a expensas de un aumento en las complicaciones cardiovasculares secundarias a la quimioterapia y a la radioterapia. Se presenta el caso de un paciente con cáncer esofágico que manifiesta angina inestable como complicación de su enfermedad coronaria multivaso tras iniciar la quimioterapia (capecitabina/oxaliplatino/epirubicina), se discuten los posibles mecanismos que subyacen al evento y se subraya la necesidad de individualizar la estratificación de riesgo previa a la quimioterapia.

Abstract The great therapeutic advances of the last decades have prolonged the survival of many cancer patients. However, these advances have been made at the expense of an increase in cardiovascular complications secondary to chemotherapy and/or radiotherapy. It is presented a patient with oesophageal cancer who manifests unstable angina as a complication of multivessel coronary artery disease after starting chemotherapy with capecitabine/oxaliplatin/epirubicin, discussing the possible mechanisms underlying the event and emphasizing the need to personalize the risk stratification before chemotherapy.

Functional outcome in chronic heart failure after exercise training: Possible predictive value of heart rate variability.

BACKGROUND: Controlled exercise training (ET) is a valuable therapeutic addition to pharmacological treatment in most patients with chronic heart failure (CHF), reducing long-term mortality, preventing cardiac remodelling and improving functional capacity. Despite the fact that the mechanism underlying its benefits might be multifactorial, a sustained improvement in autonomic balance is usually attributed as a major effect. Nevertheless, not all eligible subjects show the same response to ET, probably due to several differences in the subpopulations enrolled. We hypothesize that some heart rate variability (HRV) indexes could be valid tools to optimize the selection and follow-up of CHF patients receiving ET intervention. METHODS: Forty patients with CHF and left ventricular ejection fraction (LVEF)≤40% under complete evidence-based pharmacological treatment were included; 20 were assigned to a program of controlled ET on a 3-times/week basis during 24 weeks, training group (TG) and 20 received a standard follow-up program, control group (CG). In each patient, full clinical assessments, echocardiography, HRV analysis and 6-minute-walk test were performed at the beginning and the end of the study. RESULTS: After 24 weeks, patients in the TG showed a significant improvement in LVEF, 6-minute walk test, functional class of symptoms and HRV parasympathetic related indices (HF and rMSSD). Patients in the CG did not exhibit any improvement in the aforementioned indices and experienced more adverse events. Moreover, an initial value of HF<150 ms2/Hz or rMSSD<20ms predicted better outcomes of the ET program, including improvements in systolic function, the distance walked in 6minutes, and the functional class of symptoms, along with a reduction in clinical events. CONCLUSIONS: In CHF patients, HRV indexes related to parasympathetic function are valid and clinically useful tools to select and follow-up those candidates that could experience superior functional improvement after ET.

Myocardial infarction induced by oral terazosin in a patient with predisposing structural cardiomyopathy: case report. / Infarto agudo de miocardio asociado al uso de terazosina oral en presencia de cardiopatía estructural predisponente: reporte de caso.

We describe a 71-year-old male patient who developed acute myocardial infarction (AMI) due to a dynamic left ventricular outflow tract obstruction induced by terazosin. After receiving terazosin, the patient had a syncope followed by angina. The electrocardiogram showed Q waves and ST segment elevation in the precordial and inferior leads. Coronary angiography evidenced a chronically occluded left anterior descending artery. Doppler-echocardiography revealed apical akinesia, hyperdynamic basal segments, systolic anterior motion of the mitral valve (SAM) and dynamic left ventricular outflow tract obstruction. Therapy with intravenous fluids and atenolol resulted in marked clinical improvement. Acute myocardial infarction resulted from low coronary perfusion pressure in a patient with a chronically diminished coronary reserve.

Describimos el caso de un hombre de 71 años de edad, que presentó un infarto agudo de miocardio debido a la obstrucción dinámica del tracto de salida del ventrículo izquierdo inducida por la terazosina. Luego de recibir dicha medicación el paciente presentó un síncope y posteriormente angina de pecho. El electrocardiograma evidenció ondas Q y sobreelevación del segmento ST en las derivaciones precordiales e inferiores. La angiografía coronaria evidenció una oclusión crónica de la arteria descendente anterior y el ecocardiograma Doppler reveló aquinesia apical, segmentos basales hiperdinámicos, movimiento anterior sistólico de la válvula mitraI y obstrucción dinámica del tracto de salida del ventrículo izquierdo. La administración intravenosa de suero fisiológico y atenolol determinó una clara mejoría clínica. Un infarto agudo de miocardio hemodinámico fue el resultado de la caída de la presión de perfusión coronaria en un paciente con disminución crónica de la reserva coronaria.

Tachycardia-dependent bilateral bundle branch block in ischemic heart disease with systolic dysfunction: case report and review of prognostic implications.

A proper characterization of frequency-dependent bundle branch blocks can provide useful prognostic information in some clinical situations. Often, this physiological event may be due to an extensive damage of infrahisian system, which poses a high risk of developing advanced atrioventricular block requiring pacemaker implantation. We describe the case of a 62 year-old man with chronic ischemic heart disease who exhibited alternating tachycardia-dependent bundle branch block during stress test. We discuss the main prognostic implications of this unusual event in the context of systolic dysfunction.

Una caracterización correcta de los bloqueos de rama dependientes de frecuencia, puede proporcionar información relevante en ciertas situaciones clínicas. A menudo, este evento fisiológico puede evidenciar la presencia de un daño extenso del sistema de conducción infrahisiano con riesgo elevado de bloqueo aurículo-ventricular avanzado y necesidad de implante de marcapasos. Describimos el caso de un hombre de 62 años con cardiopatía isquémica crónica, que exhibió un bloqueo de rama bilateral alternante taquicardia-dependiente durante el esfuerzo ergométrico, discutiendo las principales implicancias pronósticas de este evento inusual en el contexto de la disfunción sistólica.

Percepciones estudiantiles sobre las propiedades del examen clínico objetivo estructurado en Uruguay. Disponiendo un cuestionario válido para analizar la factibilidad del nuevo formato durante la transición curricular / Student perceptions on properties of the objective structured clinical examination in Uruguay. The use of a valid questionnaire to analyse the feasibility of the new format during curriculum transition

INTRODUCCIÓN: Aunque el formato de examen clínico objetivo estructurado (ECOE) se aplica en Uruguay desde 2004 proveyendo medidas confiables de rendimiento, las percepciones sobre sus propiedades y el grado de satisfacción estudiantiles no han sido exploradas. OBJETIVO: La siguiente experiencia estuvo dirigida a evaluar la validez aparente del ECOE como aporte al estudio de su factibilidad local. MATERIAL Y MÉTODOS: Al final del ciclo propedéutico, la subcohorte cursando en el Hospital Universitario contestó un cuestionario de 28 ítems dirigido a explorar las percepciones sobre las propiedades del ECOE en los potenciales factores «diseño» y «validez aparente». Tras analizar su confiabilidad, se depuró el formulario para proveer una herramienta más breve y fiable. RESULTADOS: El cuestionario original mostró una confiabilidad aceptable (alfa de Cronbach = 0,70), dominando las opiniones de «acuerdo/total acuerdo» sobre autenticidad de los estímulos, dinámica, pertinencia y justicia del examen. Los estudiantes percibieron obstáculos organizativos durante la prueba, manifestando desacuerdo en incluir alguna estación dirigida a evaluar solamente habilidades para la comunicación y requiriendo instancias de devolución (feedback) personalizada. La versión depurada del cuestionario original provee medidas consistentes sobre las percepciones estudiantiles y resulta una herramienta útil que podría aplicarse extensamente. Se discuten los aportes de esta experiencia al estudio de la factibilidad del nuevo formato durante la transición curricular. CONCLUSIONES: El ECOE es bien evaluado por los estudiantes al final del ciclo propedéutico, lo que apoya su validez. Deben aprovecharse sus potenciales formativos proveyendo feedback efectivo a estudiantes, tutores clínicos e institución

INTRODUCTION: Although an objective structured clinical examination (OSCE) format has been applied in Uruguay since 2004, and providing reliable performance measures, perceptions of it properties and level of student satisfaction have not been determined. OBJECTIVE: To evaluate the face validity of OSCE format as a contribution to its local feasibility study. MATERIAL AND METHODS: At the end of the introductory clinical course, the sub-cohort enrolled at the University Hospital responded to a 28-item questionnaire aimed at exploring perceptions about the properties of the OSCE about the potential factors 'design' and 'apparent validity'. After analysing the reliability of the original questionnaire, the questionnaire was refined in an attempt to provide a shorter and more reliable tool. RESULTS: The original questionnaire showed good internal consistency (Cronbach Alpha = 0.70), with a dominance of 'agreement/total agreement' opinions on authenticity of the stimuli, dynamic, relevance, and equity of the test. Students perceived organisational obstacles during the test, expressing disagreement to include some stations only aimed at assessing communication skills, and requiring personalised feedback sessions. The refined version of the questionnaire provides consistent measures on student perceptions and is a useful tool that can be widely applied. A discussion is presented on the contributions of this experience to a comprehensive feasibility study of the new format during curriculum transition. CONCLUSIONS: The OSCE is well evaluated by students at the end of the propaedeutic course, supporting its validity. Educational potentials of the new format should be exploited, providing effective feedback to students, clinical teachers, and institutions

Efectos de la estimulación endocárdica prolongada sobre la sincronía mecánica ventricular izquierda. Ensayo piloto aplicando análisis de fase por tomografía computada por emisión de fotón único gatillada. Estimulación prolongada y disincronía mecánica / Effects of prolonged endocardial stimulation on left ventricular mechanical synchrony. A pilot study applying gated-SPECT phase analysis. Endocardial stimulation and dyssynchrony

Resumen: Objetivo: Evaluar la disincronía mecánica ventricular izquierda (DMVI) asociada a la estimulación endocárdica prolongada del ventrículo derecho mediante el ensayo piloto de una nueva técnica de imagen en Uruguay. Métodos: Se estudiaron 12 pacientes con marcapasos implantados al menos hace un año utilizando SPECT gatillada con 99mTc-MIBI y análisis de fase en reposo. Se registraron variables clínicas, duración del QRS, tasa, modo y sitio de estimulación ventricular, presencia y extensión de infarto e isquemia, volúmenes cavitarios y FEVI en reposo. Utilizando V-Sync de Emory Cardiac Toolbox se obtuvieron desviación estándar y ancho de banda de fase en reposo (grados), comparando los individuos con FEVI ≥ y < 50% con una población control. Resultados: Los pacientes de la serie con estimulación endocárdica prolongada en el ventrículo derecho exhibieron marcada DMVI. Los pacientes con FEVI moderada/severamente disminuida (con diámetros cavitarios mayores, estimulación septal, infarto extenso o isquemia significativa) exhibieron mayor disincronía que aquellos con FEVI conservada/levemente disminuida (ancho de banda = 144.33o vs. 77.41o, p < 0.05; desviación estándar = 46.67o vs. 26.81o, p < 0.05). Conclusiones: En la cardiopatía isquémica la elevada tasa de estimulación endocárdica crónica se asocia con marcada DMVI, aun cuando la función sistólica esté conservada. El análisis de fase podría ser una herramienta válida para evaluar la disincronía asociada al infarto en pacientes con marcapasos, y aportar a la indicación oportuna del pasaje (upgrading) al modo de estimulación biventricular.

Abstract: Objetive: To evaluate left ventricular mechanical dyssynchrony (LVMD) associated with prolonged right ventricular pacing through an innovative imaging technique as a pilot study in Uruguay. Methods: A 99mTc-MIBI gated-SPECT and phase analysis was performed in 12 patients with pace-makers implanted at least one year before scintigraphy, due to advanced atrioventricular block. Clinical data, QRS duration, rate, mode and site of pacing in right ventricle, chamber diameters, presence and extension of myocardial scar and ischaemia, as well as LVEF at rest, were recorded. Using V-Sync of Emory Cardiac Toolbox, a standard deviation (PSD) and band-width (PBW) from rest phase histogram was obtained and these indexes were compared with controls in the subgroups of patients with LVEF ≥ 50% and < 50%. Results: Patients with prolonged RV endocardial pacing exhibited marked LVMD. More severe dyssynchrony was found in patients with impaired LVEF than in patients with preserved LVEF (PSD: 46.67o vs. 26.81o, P < .05; PBW: 144.33o vs. 77.41o, P < .05). Higher left ventricle diameters, extensive infarct, or significant ischaemia were found in patients with impaired LVEF. Conclusions: Chronic right ventricular pacing was invariably associated with LVMD, even when systolic function was preserved. Phase analysis could be a potentially useful technique to evaluate LMVD associated with myocardial scar in patients with pacemakers, and to decide promptly the upgrading to biventricular pacing.