[Aortic valve calcification evaluated by echocardiography associated with baseline conduction abnormalities as a predictor for pacemaker placement after aortic valve replacement]. / La extension de la calcificación aórtica evaluada mediante ecocardiografia asociada a trastornos de la conducción como predictors de marcapasos dedinitivos en el postoperatorio de cambio valvular aórtico.

INTRODUCTION: Aortic valve replacement in patients with severe aortic stenosis may be complicated by complete atrioventricular block (CAVB), requiring a permanent pacemaker (PPM) implantation. Predicting this complication could help to plan the surgical. OBJECTIVE: Determine whether electrocardiography and echocardiography are useful methods for predicting the need for PPM. MATERIAL AND METHODS: A retrospective, observational and transversal study was performed. An echocardiography based semi-quantitative classification was implemented to graduate the extent of calcification of the aortic valve. RESULTS: We included 95 patients; 10 of them required PPM implantation (10.52%). In the pre-surgical basal electrocardiogram we observed that 90% of patients that required PPM had conduction abnormalities as opposed to only 24.7% in the other group, p = 0.001. A 1st and 2nd degree AV block (AVB 1 and 2) was identified in 8 patients that subsequently needed PPM (80%) vs. 5 patients (5.9%), in the group that did not required it, p = 0.001.OR 41.7, IC 95% 6.5-68. We found a grade 3 calcification extent in 80% of patients who required PPM implant compared with only 17.6% of patients in the other group, p = 0.04, OR 4.8, IC 95% 0.76-29. The AVB 1 and 2 were the single predictor in multivariate analysis but the calcification 3 + AVB 1 and 2, increased sensibility. CONCLUISON: In patients with aortic stenosis in whom aortic valve replacement was performed, identifying AVB 1 and 2 on the basal electrocardiogram is a useful tool in order to identify requirement of PPM. The grade 3 of calcification extent increased the sensibility of this prediction.

Outlook of coronary ectasia at the National Institute of Cardiology Ignacio Chávez: a cross-sectional study.

INTRODUCTION: Coronary Ectasia (CE) is a pathological remodeling with a low worldwide prevalence. It is defined as a diffuse dilatation greater than 1.5 times the diameter of the adjacent segments of the same or different coronary arteries. OBJECTIVE: To document the clinical and angiographic characteristics, and medical treatment at the discharge of patients diagnosed with coronary ectasia who attended the National Institute of Cardiology (INC). METHODS: Cross-sectional study with a non-experimental descriptive design, with a non-probabilistic convenience sampling. RESULTS: Of 69 patients who attended the INC with a diagnosis of CD, most were men, with a mean age of 56 + 11 years, the most common coronary risk factor in patients with CE was smoking 58% (40); it was associated mostly with an acute myocardial infarction ST-segment elevation (STEMI) 65.2% (45), of frequent location in the lower face 40% (18), correlated with the most affected artery is the Right Coronary Artery (CD) 69.6% (48), followed by the circumflex (Cx) 56.5% (39). A mean LVEF of 47 + 9.72 was evident within the ventricular function. As well as the preferential use of dual antiplatelet therapy with anticoagulant (DAP + OAC) in 58% (40) at the discharge of each patient from the INC. CONCLUSION: CE is a not uncommon pathological remodeling in INC. This study showed that STEMI is the most typical manifestation of CE, diagnostic coronary angiography identified a type 3 Markis, so a low rate of mortality and recurrence of cardiovascular events would be expected, and despite the lack of consensus on the ideal therapy, at the INC individualized treatment is preferred, recommending lifestyle changes, and using triple therapy (DAP + OAC) as a medical treatment only at the time of patient discharge.

INTRODUCCIÓN: La ectasia coronaria (EC) es una remodelación patológica con una prevalencia mundial baja. Se define como una dilatación difusa mayor a 1.5 veces el diámetro de los segmentos adyacentes de esta o diferentes arterias coronarias. OBJETIVO: Documentar las características clínicas y angiográficas, y el tratamiento médico que reciben los pacientes con diagnóstico de EC en el Instituto Nacional de Cardiología (INC). MÉTODOS: Estudio de tipo transversal con diseño no experimental descriptivo, con un muestreo por conveniencia no probabilístico. RESULTADOS: De 69 pacientes que asistieron al INC con diagnóstico de EC la mayor parte eran hombres, con una media de edad de 56 ± 11 años, el factor de riesgo coronario más común en los pacientes con EC fue el tabaquismo, en 40 (58%); se asoció un infarto agudo de miocardio con elevación del segmento ST (IAMCEST) en 45 (65.2%), de localización frecuente en la cara inferior 18 (40%), relacionado con la arteria más afectada, la coronaria derecha 48 (69.6%), seguida de la circunfleja 39 (56.5%). Destaca el uso preferente de la terapia antiplaquetaria dual con anticoagulante (APD+ACO) en 40 (58%) al egreso de cada paciente del INC. CONCLUSIÓN: La EC es una remodelación patológica no infrecuente en el INC. En este estudio se evidenció que el SCA-IAMCEST es la manifestación más típica de la EC, la coronariografía diagnóstica identificó un Markis tipo 3, por lo que se esperaría una tasa baja de mortalidad y recurrencia de eventos cardiovasculares y a pesar de no existir un consenso sobre la terapia ideal, en el INC se prefiere el tratamiento individualizado, recomendando modificación en el estilo de vida y empleando como tratamiento médico el uso de la triple terapia (APD+ACO) solo al momento de egreso del paciente.

Women with Acute Myocardial Infarction: Clinical Characteristics, Treatment, and In-Hospital Outcomes from a Latin American Country.

Background: Women are underrepresented in acute myocardial infarction (AMI) studies. Furthermore, there is scarce information regarding women with AMI in Latin America. Aims: To describe the presentation, clinical characteristics, risk factor burden, evidence-based care, and in-hospital outcome in a population of women with AMI admitted to a coronary care unit (CCU) in Mexico. Methods: Retrospective cohort study including patients with AMI admitted from January 2006 to December 2021 in a CCU. We identified patients with ST-segment elevation myocardial infarction (STEMI) and non-ST-segment elevation myocardial infarction (NSTEMI). We described demographic characteristics, clinical variables, treatment, and in-hospital outcomes according to gender. Cox regression analysis was used to identify predictors of mortality. Results: Our study included 12,069 patients with AMI, of whom 7,599 had STEMI and 4,470 had NSTEMI. Women represented 19.6% of the population. Women had higher rates of hypertension, diabetes, stroke, and atrial fibrillation than men. For STEMI, women were less likely to receive reperfusion therapy (fibrinolysis; 23.7 vs. 28.5%, p < 0.001 and primary percutaneous coronary intervention (PCI); 31.2 vs. 35.1%, p = 0.001) and had more major adverse events than men: heart failure (4.2 vs. 2.5%, p = 0.002), pulmonary edema (3.4% vs. 1.7%, p < 0.001), major bleeding (2.1% vs. 1%, p = 0.002), stroke (1.3% vs. 0.6%, p = 0.008), and mortality (15.1% vs. 8.1%, p < 0.001). For NSTEMI, women were less likely to undergo coronary angiography or PCI and had more major bleeding and mortality. Multivariate Cox regression analysis revealed that females had an increase in mortality in STEMI and NSTEMI (HR 1.21, CI 1.01-1.47, p = 0.05 and HR 1.39, CI 1.06-1.81, p = 0.01). Conclusion: Real-world evidence from a hospital in a Latin American low- to middle-income country (LMIC) showed that women with AMI had more comorbidities, received less reperfusion treatment or invasive strategies, and had worse outcomes. In STEMI and NSTEMI, female gender represented an independent predictor of in-hospital mortality.

Body mass index is associated with low postoperative cardiac output in patients undergoing aortic valve replacement.

Background: Overweight and obesity (O/O) generate lipotoxicity of the cardiac fiber and increase the incidence and progression of aortic valve stenosis. The low cardiac output syndrome (LCOS) is a timing complication after to aortic valve replacement (AVR) surgery. Objective: The objective of the study was to investigate if body mass index (BMI) kg/m2 is a risk factor associated with LCOS and mortality in the post-operative period of AVR. Methods: A historic cohort study was designed, including patients with severe aortic stenosis (SAS), who were subjected to AVR. Results: 152 patients were included, 45 (29.6%), with normal weight (NW), 60 were overweight (39.5%), and 47 obese (30.9%). The prevalence of systemic hypertension (HT) was higher in O/O (p < 0.0001). Incidence of LCOS was 44.7%, being more frequent in the O/O groups compared to the NW group, 43.3%, 68.1%, and 22.2%, respectively, (p < 0.05 in overweight and p < 0.0001 in the obese). Assessing the presence or absence of LCOS associated with BMI as a numerical variable, we found that women, HT, BMI, left ventricular mass, and valve size, were associated with LCOS (p < 0.02, p < 0.02, p < 0.001, p < 0.032, and p < 0.045, respectively). Mortality was higher in patients who had LCOS (p < 0.02). Multivariate model showed that BMI was an independent risk factor for LCOS (odds ratio [OR] 1.21 [95% CI 1.08-1.35], p < 0.001). Conclusion: BMI is a risk factor associated to LCOS in the post-operative period of AVR in patients with SAS.

Antecedentes: El sobrepeso y la obesidad (O/O) generan lipotoxicidad de la fibra cardíaca y aumentan la incidencia y progresión de la estenosis de la válvula aórtica. El síndrome de bajo gasto cardíaco (SBGC) es una complicación postquirúrgica de la cirugía de reemplazo de válvula aórtica (RVA). Objetivo: Investigar si el índice de masa corporal kg/m2 (IMC) es un factor de riesgo asociado con SBGC y mortalidad en el postoperatorio de RVA. Métodos: Se diseñó un estudio de cohorte histórico, que incluyó pacientes con estenosis aórtica importante (EAI), que fueron sometidos a RVA. Resultados: Se incluyeron 152 pacientes, 45 (29.6%), con peso normal (N), 60 tenían sobrepeso (39.5%) y 47 obesos (30.9%). La prevalencia de hipertensión sistémica (HT) fue mayor en O/O (p < 0.0001). La incidencia de SBGC fue del 44.7%, siendo más frecuente en los grupos O/O en comparación con el grupo N, 43.3%, 68.1%, 22.2% respectivamente, (p < 0.05 en sobrepeso y p < 0.0001 en obesos). Al evaluar la presencia o ausencia de SBGC asociado con el IMC como una variable numérica, encontramos que las mujeres, HT, IMC, masa ventricular izquierda y tamaño de la válvula, se asociaron con SBGC (p < 0.02, p < 0.02, p < 0.001, p < 0.032, p < 0.045, respectivamente). La mortalidad fue mayor en pacientes con SBGC (p < 0.02). El modelo multivariado mostró que el IMC fue un factor de riesgo independiente asociado a SBGC [OR 1.21 (IC 95% 1.08-1.35), p < 0.001]. Conclusión: El IMC es un factor de riesgo asociado a SBGC en el postoperatorio de RVA en pacientes con EAI.

Central blood pressure and vascular stiffness in Mexican population.

Introduction: Central blood pressure (CBP) is considered a measure of prognostic value for cardiovascular risk. In turn, the aortic pulse wave velocity (PWVAo) and augmentation index (Aix) have been related to arterial stiffness and cardiovascular risk. Controversies exist regarding the reference values in different ethnic groups, ages, and anthropometrics. The objective of this study is to evaluate the CBP and arterial stiffness parameters in a Mexican population by age, gender, and anthropometry. Methods: Between 2015 and 2016, 1009 apparently healthy subjects were recruited in the Instituto Nacional de Cardiología Ignacio Chávez. Using the Arteriograph (TensioMed) equipment with an oscillometric technique, CBP, central pulse pressure (cPP), PWVAo, and Aix were acquired. All results were automatically obtained by computer software version 3.0.0.4. Results: Female sex was prevalent (72%), mean age was 47 ± 12 years; 26% had normal weight, 43% were overweight, and 30% had obesity. The reference values were higher than those reported in other populations. PWVAo and Aix were always found to be higher in females. A central-brachial pressure gradient was observed in < 40 years with lower CBP. Body mass index (BMI) presented a direct and positive correlation with CBP (p < 0.001); however, PWVAo and Aix were not modified. Conclusion: CBP, cPP, PWVAo, and Aix parameters should be considered based on age, gender, and BMI. In Mexican population, CBP and cPP values were higher compared with other previously reported values, especially in women, the elderly, and obese. PWVAo and Aix are higher in older women; however, they are not modified by BMI.

Introducción: La presión central aórtica (PCA) se considera una medida del valor pronóstico. A su vez, la velocidad de la onda del pulso aórtico (VOPA) y el índice de aumento (IA) se han relacionado con la rigidez arterial y riesgo cardiovascular. Existen controversias sobre los valores de referencia en diferentes grupos. El objetivo de este estudio es evaluar estos parámetros en una población mexicana por edad, género y antropometría. Métodos: Entre 2015 y 2016 se reclutaron 1,009 sujetos aparentemente sanos en el Instituto Nacional de Cardiología Ignacio Chávez. Usando el equipo de Arteriograph (TensioMed) con técnica oscilométrica, se adquirieron: PCA, presión de pulso central, VOPA e IA. Todos los resultados fueron obtenidos automáticamente. Resultados: El sexo femenino fue prevalente (72%), edad de 47 ± 12 años; 26% con peso normal, 43% con sobrepeso y 30% con obesidad. Todos los valores fueron superiores a los reportados en otras poblaciones. VOPA e IA siempre fueron más altos en mujeres. Se observó un gradiente de presión central-braquial en < 40 años, con menor PCA. El IMC presentó una correlación directa y positiva con la PCA (p < 0,001), sin embargo, VOPA e IA no se modificaron. Conclusión: Los parámetros de PCA, VOPA e IA deben considerarse en función de edad, género e IMC. En una población mexicana, los valores de PCA fueron más altos en comparación con informados previamente (Europa y Asia), especialmente en mujeres, ancianos y obesos. VOPA e IA son más altos en mujeres mayores; sin embargo, no son modificados por el IMC.

Fourth mitral valve replacement in a 15-year span in a woman of childbearing age.

There is no report of four valve replacement surgeries in a woman during 15-year follow-up. A 23-year-old female was diagnosed at 7 years with rheumatic fever. She developed severe mitral regurgitation and at the same age a prosthetic valve was placed. In the next 15 years her mitral valve was changed 3 times because of clinical, echocardiographic, and histopathologic evidence of thrombosis. Her coagulation tests all showed infratherapeutic international normalized ratio and by the age of 15 years she had had an ischemic stroke with total recovery. She developed a normal pregnancy by the age of 19 years with no complications. This case exposes the complexity of the decision making that cardiologists face in terms of choosing the type of prosthetic valve that should be indicated in a woman of childbearing age. With each surgical valve replacement prognosis is less favorable and choosing the best therapy remains a challenge for the heart team. .

[Evaluation of the antithrombotic strategy in low thrombotic risk patients who underwent aortic valve replacement with a bioprosthesis]. / Evaluación de la estrategia de terapia antitrombótica posterior al cambio valvular aórtico con válvulas biológicas en pacientes de bajo riesgo trombótico.

According to current guidelines, in patients without additional risk factors who have undergone aortic valve replacement with a bioprosthesis, anticoagulation in the first 3 months after surgery is still a matter of debate. According to current evidence, aspirin in low doses is a reasonable alternative to vitamin K antagonists (VKA). A comparison is made between the incidence of thrombotic and haemorrhagic complications in patients with low thrombotic risk who underwent aortic valve replacement with a bioprosthesis in the National Institute of Cardiology of Ignacio Chávez of Mexico. The hypothesis: aspirin as monotherapy has a beneficial effect compared to VKA. The studied patients were the low thrombotic risk patients who underwent aortic valve replacement with a bioprosthesis in the National Institute of Cardiology of Ignacio Chávez of Mexico from 2011 to 2015. The groups studied were: aspirin only, VKA only, and the combination of VKA plus aspirin. The patients were retrospectively followed-up for 12 months, and the thrombotic and haemorrhagic complications were documented. Of the 231 patients included in the study, only one patient in the VKA only group presented with a haemorrhagic complication. No thrombotic complications were observed. In the present study no thrombotic complications were observed in patients who did not receive anticoagulation in the first 3 months after an aortic valve replacement with a bioprosthesis after a follow up period of 12 months. This suggests that the use of aspirin only is safe during this period.

Pulmonary embolism and megaloblastic anemia: is there a link? A case report an literature review.

Many factors have been associated with venous thromboembolism. Among them, vitamin B12 deficiency can produce elevated homocysteine levels, which is a risk factor for venous embolism, since the latter interferes with the activation of Va coagulation factor by activation of C protein. We present a case of a patient with metabolic syndrome with apparently unprovoked pulmonary embolism. After careful evaluation, megaloblastic anemia was detected. Even though the patient had biochemistry findings of hemolysis and blood smear did not showed fragmented erythrocytes, which is consistent with pseudo-microangiopathic hemolytic anemia.

Panorama de la ectasia coronaria en el Instituto Nacional de Cardiología Ignacio Chávez: un estudio transversal / Outlook of coronary ectasia at the National Institute of Cardiology Ignacio Chávez: a cross-sectional study

Resumen Introducción: La ectasia coronaria (EC) es una remodelación patológica con una prevalencia mundial baja. Se define como una dilatación difusa mayor a 1.5 veces el diámetro de los segmentos adyacentes de esta o diferentes arterias coronarias. Objetivo: Documentar las características clínicas y angiográficas, y el tratamiento médico que reciben los pacientes con diagnóstico de EC en el Instituto Nacional de Cardiología (INC). Métodos: Estudio de tipo transversal con diseño no experimental descriptivo, con un muestreo por conveniencia no probabilístico. Resultados: De 69 pacientes que asistieron al INC con diagnóstico de EC la mayor parte eran hombres, con una media de edad de 56 ± 11 años, el factor de riesgo coronario más común en los pacientes con EC fue el tabaquismo, en 40 (58%); se asoció un infarto agudo de miocardio con elevación del segmento ST (IAMCEST) en 45 (65.2%), de localización frecuente en la cara inferior 18 (40%), relacionado con la arteria más afectada, la coronaria derecha 48 (69.6%), seguida de la circunfleja 39 (56.5%). Destaca el uso preferente de la terapia antiplaquetaria dual con anticoagulante (APD+ACO) en 40 (58%) al egreso de cada paciente del INC. Conclusión: La EC es una remodelación patológica no infrecuente en el INC. En este estudio se evidenció que el SCA-IAMCEST es la manifestación más típica de la EC, la coronariografía diagnóstica identificó un Markis tipo 3, por lo que se esperaría una tasa baja de mortalidad y recurrencia de eventos cardiovasculares y a pesar de no existir un consenso sobre la terapia ideal, en el INC se prefiere el tratamiento individualizado, recomendando modificación en el estilo de vida y empleando como tratamiento médico el uso de la triple terapia (APD+ACO) solo al momento de egreso del paciente.

Abstract Introduction: Coronary Ectasia (CE) is a pathological remodeling with a low worldwide prevalence. It is defined as a diffuse dilatation greater than 1.5 times the diameter of the adjacent segments of the same or different coronary arteries. Objective: To document the clinical and angiographic characteristics, and medical treatment at the discharge of patients diagnosed with coronary ectasia who attended the National Institute of Cardiology (INC). Methods: Cross-sectional study with a non-experimental descriptive design, with a non-probabilistic convenience sampling. Results: Of 69 patients who attended the INC with a diagnosis of CD, most were men, with a mean age of 56 + 11 years, the most common coronary risk factor in patients with CE was smoking 58% (40); it was associated mostly with an acute myocardial infarction ST-segment elevation (STEMI) 65.2% (45), of frequent location in the lower face 40% (18), correlated with the most affected artery is the Right Coronary Artery (CD) 69.6% (48), followed by the circumflex (Cx) 56.5% (39). A mean LVEF of 47 + 9.72 was evident within the ventricular function. As well as the preferential use of dual antiplatelet therapy with anticoagulant (DAP + OAC) in 58% (40) at the discharge of each patient from the INC. Conclusion: CE is a not uncommon pathological remodeling in INC. This study showed that STEMI is the most typical manifestation of CE, diagnostic coronary angiography identified a type 3 Markis, so a low rate of mortality and recurrence of cardiovascular events would be expected, and despite the lack of consensus on the ideal therapy, at the INC individualized treatment is preferred, recommending lifestyle changes, and using triple therapy (DAP + OAC) as a medical treatment only at the time of patient discharge.

[Severe myocardial disease in a case of Barlow's syndrome]. / Daño miocárdico grave en un case de síndrome de Barlow.

The Barlow's syndrome is a disease characterized by the presence of mitral valve prolapse and a wide range of signs and symptoms. We know that its manifestations has a great variety existing cases with little clinical expression as those seen frequently in daily practice or the other side opposite completely in which, the syndrome is so complex getting to the patient to present many symptoms secondary to hemodynamics alterations that reduce by much its quality of life and even modify its prognosis.The case that we present is a female patient of 25 years old with Barlow's syndrome and functional class II-III of NewYork Heart Association as a result of the alterations in the contractility function of the heart that finally caused her death.

[EuroSCORE underestimate the mortality risk in cardiac valve surgery of Mexican population]. / EuroSCORE subestima el riesgo de mortalidad en cirugía cardiaca valvular de población mexicana.

OBJECTIVE: The EuroSCORE (European System for cardiac operative risk evaluation) stratifies cardiac risk surgery in easy and accessible manner; it was validated in North America with good results but in many countries of Latin America is used routinely without prior validation. Our objective was to validate the EuroSCORE in patients with cardiac valve surgery at the Instituto Nacional de Cardiología Ignacio Chávez (INCICh) in México. METHODS: EuroSCORE additive and logistic models were used to predict mortality in adults undergoing cardiac valve surgery from march 2004 to march 2008. The goodness of fit test of Hosmer-Lemeshow was used to evaluate the calibration. The area under the ROC curve was calculated to determinate discrimination. RESULTS: We included 1188 patients with ages of 51.3±14.5 years, 52% women. There were significant differences in the prevalence of risk factors among the INCICh and the EuroSCORE populations. Total mortality was 9.68% versus 5% and 5.6% predicted by additive and logistic EuroSCORE. According to additive EuroSCORE the risk was low in 11.3%, intermediate in 52.9% and high in 35.9%; for these groups the mortality was .7%, 6.34% and 17.4% against those predicted of 2%, 3.9% and 7.64%. Hosmer-Lemeshow test had a P<.001 for both models and the area under the ROC curve was .707 and .694 for additive and logistic EuroSCORE. CONCLUSION: In the INCICh 88.7% of patients with cardiac valve surgery had intermediate to high risk and EuroSCORE underestimated the risk of mortality.

[Dual chamber pacemakers: common problems and how to treat them]. / Marcapasos doble cámara: problemas comunes y cómo resolverlos.

In the last ten years the technology in Electrophysiology and Cardiac Parcing has advanced rapidly until the arrive of the implantable cardioverter defibrillator for the prevention of Sudden Death and also to the three chamber pacing for ventricular resinchronization as a treatment for advanced heart failure. In the middle of these we have dual chamber pacemakers. The increasing expectative of life worldwide gives the need and more frequency of implanting dual chamber pacemakers with the exception of the patient with chronic atrial fibrillation. For these reasons, it is important not only to detect the common problems of the dual chamber pacemakers but how to treat them. In this review we will define pacemaker pseudomalfunction: the identification of fusion and pseudofusion beats; the normal pacemaker functions that could be confused with malfunction. About malfunction it will be described the causes and the way for treating oversensing, undersensing, loss of capture, loss of output; how to identify and to treat pacemaker reset, myopotentials stimulation, pacemaker syndrome and finally pacemaker-mediated tachycardia.

Inaccurate electrocardiographic interpretation of long QT: the majority of physicians cannot recognize a long QT when they see one.

BACKGROUND: Physicians in all fields of medicine may encounter patients with long QT syndrome (LQTS). It is important to define the percentage of physicians capable of distinguishing QT intervals that are long from those that are normal because LQTS can be lethal when left untreated. OBJECTIVES: The purpose of this study was to define the percentage of physicians in the different disciplines of medicine who can recognize a long QT when they see one. METHODS: We presented the ECGs of two patients with LQTS and two healthy females to 902 physicians (25 world-renowned QT experts, 106 arrhythmia specialists, 329 cardiologists, and 442 noncardiologists) from 12 countries. They were asked to measure the QT, calculate the QTc (the QT interval corrected for the heart rate), and determine whether the QT is normal or prolonged. RESULTS: For patients with LQTS, >80% of arrhythmia experts but <50% of cardiologists and <40% of noncardiologists calculated the QTc correctly. Underestimation of the QTc of patients with LQTS and overestimation of the QTc of healthy patients were common. Interobserver agreement was excellent among QT experts, moderate among arrhythmia experts, and low among cardiologists and noncardiologists (kappa coefficient = 0.82, 0.44, and < 0.3, respectively). Correct classification of all QT intervals as either "long" or "normal" was achieved by 96% of QT experts and 62% of arrhythmia experts, but by only <25% of cardiologists and noncardiologists. CONCLUSIONS: Most physicians, including many cardiologists, cannot accurately calculate a QTc and cannot correctly identify a long QT.

Body mass index is associated with low postoperative cardiac output in patients undergoing aortic valve replacement / El índice de masa corporal se asocia a bajo gasto cardiaco postoperatorio de pacientes sometidos a reemplazo valvular aórtico

Abstract Background: Overweight and obesity (O/O) generate lipotoxicity of the cardiac fiber and increase the incidence and progression of aortic valve stenosis. The low cardiac output syndrome (LCOS) is a timing complication after to aortic valve replacement (AVR) surgery. Objective: The objective of the study was to investigate if body mass index (BMI) kg/m2 is a risk factor associated with LCOS and mortality in the post-operative period of AVR. Methods: A historic cohort study was designed, including patients with severe aortic stenosis (SAS), who were subjected to AVR. Results: 152 patients were included, 45 (29.6%), with normal weight (NW), 60 were overweight (39.5%), and 47 obese (30.9%). The prevalence of systemic hypertension (HT) was higher in O/O (p < 0.0001). Incidence of LCOS was 44.7%, being more frequent in the O/O groups compared to the NW group, 43.3%, 68.1%, and 22.2%, respectively, (p < 0.05 in overweight and p < 0.0001 in the obese). Assessing the presence or absence of LCOS associated with BMI as a numerical variable, we found that women, HT, BMI, left ventricular mass, and valve size, were associated with LCOS (p < 0.02, p < 0.02, p < 0.001, p < 0.032, and p < 0.045, respectively). Mortality was higher in patients who had LCOS (p < 0.02). Multivariate model showed that BMI was an independent risk factor for LCOS (odds ratio [OR] 1.21 [95% CI 1.08-1.35], p < 0.001). Conclusion: BMI is a risk factor associated to LCOS in the post-operative period of AVR in patients with SAS.

Resumen Antecedentes: El sobrepeso y la obesidad (O/O) generan lipotoxicidad de la fibra cardíaca y aumentan la incidencia y progresión de la estenosis de la válvula aórtica. El síndrome de bajo gasto cardíaco (SBGC) es una complicación postquirúrgica de la cirugía de reemplazo de válvula aórtica (RVA). Objetivo: Investigar si el índice de masa corporal kg/m2 (IMC) es un factor de riesgo asociado con SBGC y mortalidad en el postoperatorio de RVA. Métodos: Se diseñó un estudio de cohorte histórico, que incluyó pacientes con estenosis aórtica importante (EAI), que fueron sometidos a RVA. Resultados: Se incluyeron 152 pacientes, 45 (29.6%), con peso normal (N), 60 tenían sobrepeso (39.5%) y 47 obesos (30.9%). La prevalencia de hipertensión sistémica (HT) fue mayor en O/O (p < 0.0001). La incidencia de SBGC fue del 44.7%, siendo más frecuente en los grupos O/O en comparación con el grupo N, 43.3%, 68.1%, 22.2% respectivamente, (p < 0.05 en sobrepeso y p < 0.0001 en obesos). Al evaluar la presencia o ausencia de SBGC asociado con el IMC como una variable numérica, encontramos que las mujeres, HT, IMC, masa ventricular izquierda y tamaño de la válvula, se asociaron con SBGC (p < 0.02, p < 0.02, p < 0.001, p < 0.032, p < 0.045, respectivamente). La mortalidad fue mayor en pacientes con SBGC (p < 0.02). El modelo multivariado mostró que el IMC fue un factor de riesgo independiente asociado a SBGC [OR 1.21 (IC 95% 1.08-1.35), p < 0.001]. Conclusión: El IMC es un factor de riesgo asociado a SBGC en el postoperatorio de RVA en pacientes con EAI.

Central blood pressure and vascular stiffness in Mexican population / Presión central aórtica y rigidez vascular en mexicanos

Abstract Introduction: Central blood pressure (CBP) is considered a measure of prognostic value for cardiovascular risk. In turn, the aortic pulse wave velocity (PWVAo) and augmentation index (Aix) have been related to arterial stiffness and cardiovascular risk. Controversies exist regarding the reference values in different ethnic groups, ages, and anthropometrics. The objective of this study is to evaluate the CBP and arterial stiffness parameters in a Mexican population by age, gender, and anthropometry. Methods: Between 2015 and 2016, 1009 apparently healthy subjects were recruited in the Instituto Nacional de Cardiología Ignacio Chávez. Using the Arteriograph (TensioMed) equipment with an oscillometric technique, CBP, central pulse pressure (cPP), PWVAo, and Aix were acquired. All results were automatically obtained by computer software version 3.0.0.4. Results: Female sex was prevalent (72%), mean age was 47 ± 12 years; 26% had normal weight, 43% were overweight, and 30% had obesity. The reference values were higher than those reported in other populations. PWVAo and Aix were always found to be higher in females. A central-brachial pressure gradient was observed in < 40 years with lower CBP. Body mass index (BMI) presented a direct and positive correlation with CBP (p < 0.001); however, PWVAo and Aix were not modified. Conclusion: CBP, cPP, PWVAo, and Aix parameters should be considered based on age, gender, and BMI. In Mexican population, CBP and cPP values were higher compared with other previously reported values, especially in women, the elderly, and obese. PWVAo and Aix are higher in older women; however, they are not modified by BMI.

Resumen Introducción: La presión central aórtica (PCA) se considera una medida del valor pronóstico. A su vez, la velocidad de la onda del pulso aórtico (VOPA) y el índice de aumento (IA) se han relacionado con la rigidez arterial y riesgo cardiovascular. Existen controversias sobre los valores de referencia en diferentes grupos. El objetivo de este estudio es evaluar estos parámetros en una población mexicana por edad, género y antropometría. Métodos: Entre 2015 y 2016 se reclutaron 1,009 sujetos aparentemente sanos en el Instituto Nacional de Cardiología Ignacio Chávez. Usando el equipo de Arteriograph (TensioMed) con técnica oscilométrica, se adquirieron: PCA, presión de pulso central, VOPA e IA. Todos los resultados fueron obtenidos automáticamente. Resultados: El sexo femenino fue prevalente (72%), edad de 47 ± 12 años; 26% con peso normal, 43% con sobrepeso y 30% con obesidad. Todos los valores fueron superiores a los reportados en otras poblaciones. VOPA e IA siempre fueron más altos en mujeres. Se observó un gradiente de presión central-braquial en < 40 años, con menor PCA. El IMC presentó una correlación directa y positiva con la PCA (p < 0,001), sin embargo, VOPA e IA no se modificaron. Conclusión: Los parámetros de PCA, VOPA e IA deben considerarse en función de edad, género e IMC. En una población mexicana, los valores de PCA fueron más altos en comparación con informados previamente (Europa y Asia), especialmente en mujeres, ancianos y obesos. VOPA e IA son más altos en mujeres mayores; sin embargo, no son modificados por el IMC.

[Follow-up of a group of patients with automatic implantable defibrillator]. / Seguimiento de un grupo de pacientes con desfibrilador automático implantable.

UNLABELLED: The automatic implantable defibrillator (AID) is the treatment of choice for primary and secondary prevention of sudden death. At the Instituto Nacional de Cardiología, since October 1996 until January 2002, 25 patients were implanted with 26 AID. There were 23 men (92%) and the mean age of the whole group, was 51.4 years. Twenty-three patients (92%) presented structural heart disease, the most common was ischemic heart disease in 13 patients (52%), with a mean ejection fraction of 37.8%. One patient without structural heart disease had Brugada Syndrome. The most frequent clinical arrhythmia was ventricular tachycardia in 14 patients (56%). The mean follow-up was of 29.3 months during which a total of 30 events of ventricular arrhythmia were treated through AID; six of them were inappropriate due to paroxismal atrial fibrillation; 10 AID patients (34%) have not applied for therapy. Three patients (12%) of the group died due to congestive heart failure refractory to pharmacologic treatment. CONCLUSION: The implant of the AID is a safe and effective measure for primary and secondary prevention of sudden death. World-wide experience evidences, that this kind of device has not modified the mortality rate due to heart failure in these patients, but it has diminished sudden arrhythmic death.

[Internal cardioversion in chronic atrial fibrillation]. / Cardioversión interna de la fibrilación auricular crónica.

The importance of atrial fibrillation has always motivated the search of new treatment alternatives. Internal cardioversion has been proposed as a choice in the treatment of atrial fibrillation, giving rise to the development of atrial defibrillator. We present the case of a 68 years old patient without structural heart disease and with diagnosis of chronic atrial fibrillation of 10 months of evolution. He received treatment with antiarrhythmic drugs and successful electrical external cardioversion, but he relapsed a week later. For this reason, we decided to perform internal cardioversion with an electrocatheter (DAIG) placed in the coronary sinus through the right jugular vein and under light sedation with propofol (2 mg/kg weight). We applied three shocks of 1, 3, and 5 joules, being able to convert to sinus rhythm without complications. The patient continues under treatment with antiarrhythmic agents. Internal cardioversion has shown to be an effective way for the treatment of chronic atrial fibrillation, using a light sedation and low energy level to reestablish the sinus rhythm.

[Trans-septal puncture for radiofrequency ablation of left accessory pathway]. / Punción transeptal para la ablación con radiofrecuencia de una vía accesoria izquierda.

We present the case of an 18-year-old male patient with diagnosis of Wolff Parkinson-White syndrome due to a left free wall accessory pathway. We performed an electrophysiology study and transseptal punction guided by transesophageal echocardiogram to via access to the left atrium. We performed successful radiofrequency ablation of the accessory pathway, observing disappearance of the delta wave on the first attempt. There were no complications. In follow-up a 10 months, the patient had no clinical nor electrocardiographic evidence of recurrence. Transseptal radiofrequency ablation is an alternative for treatment of some arrhythmias localized in the left side of the heart.

[Long-term follow-up of 413 patients with atrioventricular accessory pathway who underwent radiofrequency catheter ablation]. / Seguimiento a largo plazo en 413 pacientes con vía accesoria atrioventricular sometidos a ablación con radiofrecuencia.

OBJECTIVE: The aim of this study was shown clinical characteristics and follow-up of patients with atrioventricular reentrant tachycardia (AVRT) who underwent radiofrequency catheter ablation (RCA) therapy. MATERIAL AND METHODS: From April 1992 to December 1995, 413 patients with AVRT underwent RCA therapy. RESULTS: Two hundred thirty four men (57%) and one hundred seventy nine women (43%) aged 31.3 +/- 16.3 years were studied. 437 single accessory pathways were found; 24 had multiple accessory pathways. Ablation therapy was successful in 381 accessory pathways. During follow-up of 7 years, AVRT recurred in 51 patients (13%) and in 80% this occurred within the first 3 months after the procedure. 56 patients underwent a second RCA therapy with success in 35 patients (83.5); two reoccurred (5.7%); 365 accessory pathways (83.5) remained without evidence of preexcitation AVRT. CONCLUSIONS: During follow-up, these patients with successful ablation therapy remained without symptoms. In patients who underwent a second RCA therapy, atrioventricular reentrant mechanism was always present.