[Comparison of peak oxygen uptake and VE/VCO2 slope, between children with and without heart failure]. / Comparación del consumo de oxígeno pico y la pendienteVE/VCO2 entre niños con y sin insuficiencia cardiaca (IC).

Heart failure is a health problem associated with disability and mortality. Physicians may stratify the risk of adult patients with heart failure using a cardiopulmonary exercise testing. Until now, in childhood this evaluation has been poorly used. The purpose of this study is to compare the peak oxygen uptake and minute ventilation/carbon dioxide production slope among children with heart failure versus children without heart disease (control). METHODS: Thirty-eight children with heart failure were compared with 194 children without heart disease. All of them performed cardiopulmonary exercise testing using a symptom-limited ramp protocol. Differences between groups were compared using Chi-squared test, Student's t test, or ANOVA. Any value of p < 0.05 was considered significant. RESULTS: Children with heart failure were older, taller, and with a higher prevalence of male gender. This group had also a lower peak oxygen uptake (27 ± 10 ml O2/kg/min) compared to the control group (37 ± 10 ml O2/kg/min); p < 0.001. The minute ventilation/carbon dioxide production was higher in the heart failure group (31 ± 4) than in controls (28 ± 6); p < 0.001. CONCLUSION: Children with heart failure showed lower peak oxygen uptake and higher minute ventilation/carbon dioxide production slope than the control group.

Cardiovascular evaluation using exercise testing performed with face masks during the COVID-19 pandemic.

OBJECTIVE: COVID-19 pandemic is associated with high incidence and fatality, however, non-communicable diseases remain a global public health problem with even greater morbidity and mortality. At present, there is a lag in diagnosis and treatment of patients with heart disease, particularly the performance of exercise testing (ET), due to the fear of aerosol generation and viral dissemination. Although some centers carry out the tests with the use of masks, the information is still superficial and preliminary. The objective of the study was to describe the ergometric performance observed when performing exercise tests during the COVID-19 (PANDEMIC-G) pandemic and to highlight the differences with those results carried out in another time, when there was no COVID-19 (NO PANDEMIC). METHOD: A cross-sectional study was carried out. PANDEMIC-G patients underwent ET between March 2020 and December 2020, once a biological triage was done and all of them wore N95 masks. They were compared to NO PANDEMIC patients that performed an ET between March 2019 and December 2019. Demographic and ergometric variables were presented and analyzed according to their type. All p < 0.05 were considered stochastically significant. RESULTS: A total of 361 ET were studied: 209 (58%) belonged to NO PANDEMIC and 152 (42%) to PANDEMIC-G. The number of ET stopped by dyspnea was greater in PANDEMIC-G (117) than in NO PANDEMIC (8). Exercise tolerance did not show significant changes. Systolic blood pressure, double product, and myocardial oxygen utilization were higher in PANDEMIC-G ET (p < 0.01). CONCLUSIONS: In the COVID-era, fewer stress tests were performed, which were suspended more frequently due to dyspnea. Higher values of systolic blood pressure and myocardial oxygen utilization were observed in PANDEMIC-G as well.

OBJETIVO: La pandemia de COVID-19 se asocia con una alta incidencia y letalidad; sin embargo, las enfermedades no transmisibles siguen siendo un problema de salud pública mundial con una morbilidad y mortalidad aún mayores. Actualmente, existe un retraso en el diagnóstico y tratamiento de los pacientes con enfermedades cardíacas, particularmente en la realización de la prueba de esfuerzo (PE), debido al temor a la generación de aerosoles y la diseminación viral. Aunque algunos centros realizan las pruebas con el uso de tapabocas, la información aún es superficial y preliminar. El objetivo del estudio fue describir el desempeño ergométrico observado al realizar pruebas de ejercicio durante la pandemia COVID-19 (PANDEMIC-G) y remarcar las diferencias con las pruebas realizadas antes de ella (NO PANDEMIC). MÉTODO: Se realizó un estudio transversal. Los pacientes con PANDEMIC-G se sometieron a PE entre marzo y diciembre de 2020, una vez que se realizó un triaje biológico y todos usaron tapabocas N95. Fueron comparados con pacientes NO PANDEMIC, que realizaron una PE entre marzo y diciembre de 2019. Las variables se presentaron y analizaron según su tipo. Todos los valores de p inferiores a 0.05 se consideraron estocásticamente significativos. RESULTADOS: Se estudiaron un total de 361 PE, donde 209 (58%) pertenecían a NO PANDEMIC y 152 (42%) a PANDEMIC-G. El número de PE detenidas por disnea fue mayor en PANDEMIC-G (n = 117) que en NO PANDEMIC (n = 8). La tolerancia al ejercicio no mostró cambios significativos. La presión arterial sistólica, el producto doble y la utilización de oxígeno del miocardio fueron mayores en las PE en el PANDEMIC-G (p < 0.01). CONCLUSIONES: En la era COVID se realizaron menos pruebas de esfuerzo, que se suspendieron con mayor frecuencia por disnea. También se observaron valores más altos de presión arterial sistólica y utilización de oxígeno del miocardio en PANDEMIC-G.

Brain magnetic resonance imaging findings in patients with mitochondrial cytopathies.

BACKGROUND: Mitochondrial cytopathies (MCs) are a heterogeneous group of clinical entities, some of which have classic phenotypes. Magnetic resonance imaging (MRI) has been reported to be helpful in the diagnosis of MC. OBJECTIVE: To correlate the most common brain MRI findings reported in patients with MC with the clinical findings in patients in different MC subgroups. DESIGN: Case series. SETTING: Patients with MCs seen at the Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubiran, Mexico City, Mexico. PATIENTS: Twenty-one patients with MC with the following phenotypes: chronic progressive external ophthalmoplegia (n = 7), Kearns-Sayre syndrome (n = 7), mitochondrial neurogastrointestinal encephalopathy (n = 6), and myoclonic epilepsy with ragged red fiber myopathy (n = 1). RESULTS: Brain MRI abnormalities were found in 20 (95%) of 21 patients. The most frequent abnormalities were widespread white matter hyperintensity in 19 patients (90%), supratentorial cortical atrophy in 18 patients (86%), and cerebellar atrophy in 13 patients (62%). Widespread white matter hyperintensity (P<.001) and supratentorial cortical atrophy (P = .001) were each correlated significantly with MC. Subsequent subgroup analyses showed that the absence of basal ganglia hyperintensity was correlated with Kearns-Sayre syndrome (P < .001) and the presence of supratentorial cortical atrophy was correlated with mitochondrial neurogastrointestinal encephalopathy (P = .005). CONCLUSIONS: The presence of widespread white matter hyperintensity and/or supratentorial cortical atrophy in brain MRI may help to establish the diagnosis of MC. The radiologist has a role to play in the workup of MC by confirming the diagnosis and possibly distinguishing different subgroups of MC.

Identification of low responders to a 300-mg clopidogrel loading dose in patients undergoing coronary stenting.

BACKGROUND: Although patients undergoing coronary stenting routinely receive dual antiplatelet treatment to reduce the risk of stent thrombosis, this undesired event still occurs. A suboptimal response to clopidogrel treatment (low responders) has been suggested to contribute to stent thrombosis. In the present study, platelet function profiles were assessed in patients undergoing coronary stenting receiving a standard 300-mg clopidogrel loading dose with the aim to identify low clopidogrel responders. MATERIALS AND METHODS: Platelet aggregation was assessed by light transmittance aggregometry following 6 microM ADP stimuli in 48 patients before and 10 min, 4 and 24 h after receiving clopidogrel front-loading. Patients having > or =40% inhibition of platelet aggregation 24 h after clopidogrel administration were defined as normal responders, whereas those having <40% inhibition were low responders. Glycoprotein (GP) IIb/IIIa activation and P-selectin expression were assessed by whole blood flow cytometry following 2 microM ADP stimuli at the same time points. Platelet function profiles were compared between normal and low clopidogrel responders. RESULTS: Twenty-seven patients (56%) were normal responders and 21 (44%) low responders. Baseline GP IIb/IIIa activation was higher in low responders (74.6+/-16.6% vs. 58.2+/-24.5%, p=0.03). Although GP IIb/IIIa activation reduced following clopidogrel front-loading in both groups, it remained increased among low responders at 24 h (58.6+/-21.3% vs. 40.2+/-28.7%, p=0.05) and during the overall study time course (p=0.02). There were no differences in P-selectin expression. CONCLUSIONS: A considerable proportion of patients have an early suboptimal response to a 300-mg clopidogrel loading dose. An increased GP IIb/IIIa activation before intervention may identify this group of patients suggesting the use of a more aggressive antithrombotic treatment in these individuals.

[Cardiac involvement in Kearns-Sayre syndrome]. / Afección cardíaca en el síndrome de Kearns-Sayre.

The mitochondrial cytopathies or oxidative-phosphorylation diseases are a diverse group of disorders that result from the structural, biochemical, or genetic derangement of mitochondria. Because mitochondrial dysfunction can affect the most highly energy-dependent organs, cardiac involvement is frequent in these diseases. To identify the clinical features of Kearns-Sayre syndrome, an entity associated with this group of diseases, we evaluated cardiac structure and function in 5 patients with Kearns-Sayre syndrome and followed the clinical course of these patients for 5 years.

[Coronary physiology and its usefulness for the interventionist cardiologist: invasive measurement of coronary flow-pressure]. / Fisiología coronaria y su utilidad para el cardiólogo intervencionista: medición invasiva de la presión y flujo coronarios.

One of the most important limitations of coronary angiography is the inability to characterize the physiological significance of an intermediate coronary stenosis. Measuring coronary blood flow and pressure provides unique information that complements anatomic evaluation and facilitates decision-making in the cardiac catheterization unit. This review discusses the fundamental concepts of coronary physiology, methodology, and clinical applications of coronary and flow measurements.

[Hemorrhagic pericarditis and cardiac tamponade in systemic lupus erythematosus. A case report]. / Reporte de un caso depericarditis hemorrágica y taponamiento cardíaco asociados a lupus eritematoso sistémico.

Systemic lupus erythematosus is a chronic inflammatory autoimmune disorder that can affect any organ or system. Although pericarditis is the most frequent cardiac manifestation of this entity, usually is not a life threatening situation. Pericardial effusion causing cardiac tamponade is a very rare complication in lupus, with an incidence less than 2%. We report a case of pericardial tamponade due to SLE with severe hemodynamic involvement in a 21-year-old woman associated to rapidly progressive glomerulonephritis, acute pancreatitis, acute acalculous cholecystitis, pleural effusion, hematologic, cutaneous and neurologic lupus activity. Recognition of this rare manifestation of SLE may be life saving.

Primary stenting of an anomalous left main trunk originating from the right coronary artery during acute myocardial infarction.

In 1.5 to 2.0% of patients with AMI referred for primary percutaneous coronary intervention, the left main trunk is identified as the culprit vessel. Among the congenital coronary anomalies, an anomalous origin of the left main trunk from the right sinus of Valsalva is very rare. A 73-year-old patient with lateral acute myocardial infarction was referred to primary angioplasty. The initial angiogram showed an anomalous origin of the left main from the right coronary artery, apparently with a septal course, with an angiographic image of intraluminal thrombus; in addition, a severe lesion was present at the distal right coronary artery. The left main and right coronary arteries were successfully treated with direct stenting. The subsequent clinical course during hospitalization was uneventful, and the patient was discharged alive.

Platelet aggregation according to body mass index in patients undergoing coronary stenting: should clopidogrel loading-dose be weight adjusted?

BACKGROUND: A 300 mg clopidogrel loading-dose (LD) is widely used as an adjunct antithrombotic treatment to reduce the risk of thrombotic events early after coronary stenting (CS). Antithrombotic drugs commonly used during percutaneous coronary interventions, such as heparin and platelet glycoprotein IIb/IIIa inhibitors, but not clopidogrel LD, are weight-adjusted, and few data are available on which is the most effective clopidogrel LD regimen. The aim of this study was to assess whether body mass index (BMI) influenced platelet response to clopidogrel LD in patients undergoing CS. METHODS: Adenosine diphosphate (ADP)-induced platelet aggregation (PA) was assessed by light transmittance aggregometry in 48 patients on aspirin treatment undergoing CS receiving a 300 mg clopidogrel LD at intervention time. PA was assessed at baseline and up to 24 hours after intervention. Patients were divided into 2 groups according to BMI: overweight (BMI greater than or equal to 25 kg/m2; 29 patients) and normal weight (BMI<25 kg/m2; 19 patients). PA was significantly higher in overweight than in normal weight patients at baseline (60.1+/-18.6%; versus 47.6+/-13.5%; p=0.01), at 24 hours (42.3+/-18.4% versus 38.5+/-18.3%; p=0.02) and during the overall study time (p=0.025). Percentage of inhibition of PA 24 hours following clopidogrel LD was suboptimal (<40%) in 59% and 26% of overweight and normal weight patients, respectively (p=0.04). An elevated BMI was the only independent predictor of suboptimal platelet response. CONCLUSION: These data suggest that overweight patients may need a higher loading-dose of clopidogrel and/or an adjunct antithrombotic treatment to adequately inhibit platelet aggregation early after CS.

Pheochromocytoma-induced acute pulmonary edema and reversible catecholamine cardiomyopathy mimicking acute myocardial infarction.

Acute noncardiogenic pulmonary edema and catecholamine-induced cardiomyopathy as the first presentations of pheochromocytoma are uncommon events, but usually rapidly fatal. A 36-year-old man presented acute pulmonary edema in a setting of hypertensive emergency after arthroscopy, later developing catecholamine-induced cardiotoxicity mimicking an acute myocardial infarction, with elevation of cardiac damage markers, normal coronary arteries, and with full recovery from electrical abnormalities. Magnetic resonance imaging revealed a right adrenal mass. Elevated levels of catecholamines and metanephrines, and a positive 131I-metaiodobenzylguanidine scan confirmed a pheochromocytoma. Once the patient had been hemodynamically stabilized, he was successfully operated.

Multiple congenital coronary artery fistulae draining into the left ventricle.

Coronary artery fistula between a coronary artery and a cardiac chamber is a rare condition, especially when multiple fistulas communicate with the left ventricle. Herein we report a case of an elderly woman with multiple diffuse coronary artery-left ventricular fistulas diagnosed by angiography. Since the coronary artery-cardiac chamber communications were multiple and diffuse neither surgery nor transcatheter coil occlusion was considered in this case.

[Care for the cardiopathy patient after percutaneous coronary intervention]. / Cuidados del paciente cardiópata tras una intervención coronaria percutánea.

At present, new indications and frontiers of interventional cardiology led to percutaneous treatment of a wide spectrum of patients who require myocardial revascularization. The physician must understand the potential benefits, procedural characteristics, and risks of percutaneous coronary intervention. In this paper, we review general concepts concerning coronary angioplasty.