QRS duration and early hemodynamic instability after coronary revascularization surgery.

INTRODUCTION AND OBJECTIVES: The duration of the QRS interval measured by ECG is a marker of ventricular dysfunction and indicates a poor prognosis. Its value in patients undergoing coronary revascularization surgery has not been established. METHODS: The study involved 203 consecutive patients (age 64+/-9 years, 74% male) scheduled for elective coronary surgery. The maximum QRS duration measured on a preoperative 12-lead ECG was recorded. Hemodynamic instability was defined as the occurrence of cardiac death, heart failure, or a need for intravenous inotropic drugs or intra-aortic balloon counterpulsation during the postoperative period. RESULTS: The occurrence of hemodynamic instability (n=94, 46%) was associated with a longer preoperative QRS duration (97.5+/-21.14 ms vs 88.5+/-16.9 ms; P=.001). The QRS duration was also longer in patients who developed heart failure (n=23; 104.3+/-22.9 ms vs. 91.1+/-18.5 ms; P=.002), needed inotropic drugs (n=77; 96.5+/-20.5 ms vs. 90.1+/-18.2 ms; P=.007) or developed postoperative atrial fibrillation (n=58; 98.2+/-23.8 ms vs. 90.4+/-17.0 ms; P=.018). Bundle branch block was associated with a greater need for intra-aortic balloon counterpulsation (29% vs 12%; P=.012) or inotropic drugs (58% vs 35%; P=.014) and a higher incidence of hemodynamic instability (69% vs 42%; P=.006). Multivariate analysis identified the following independent predictors of hemodynamic instability: QRS duration (adjusted odds ratio [OR] per 10 ms=1.49; 95% confidence interval [CI], 1.11-2; P=.007), the lack of an arterial graft (OR=3.6; 95% CI, 1.14-11.6; P=.029) and extracorporeal circulation time (OR per min=1.013; 95% CI, 1.003-1.023; P=.013). CONCLUSIONS: The intraventricular conduction delay, or QRS duration, was associated with a higher risk of postoperative hemodynamic instability following coronary surgery.

Duración del QRS y deterioro hemodinámico precoz tras cirugía de revascularización coronaria / QRS Duration and Early Hemodynamic instability after coronary Revascularization Surgery

Introducción y objetivos. La duración del intervalo QRS en el ECG es un marcador de disfunción ventricular y peor pronóstico. Su valor en pacientes sometidos a cirugía de revascularización coronaria no ha sido establecido. Métodos. Estudiamos a 203 pacientes consecutivos (64 ± 9 años de edad; el 74% varones) programados para cirugía electiva coronaria. Se registró la duración máxima del intervalo QRS en el ECG de 12 derivaciones preoperatorio. Definimos inestabilidad hemodinámica como la aparición de muerte cardiaca, insuficiencia cardiaca, uso de fármacos inotrópicos intravenosos o balón de contrapulsación intraaórtico durante el postoperatorio. Resultados. La aparición de inestabilidad hemodinámica (n = 94 [46%]) se asoció a una mayor duración del intervalo QRS preoperatorio (97,5 ± 21,14 frente a 88,5 ± 16,9 ms; p = 0,001). El QRS fue mayor en quienes apareció insuficiencia cardiaca (n = 23; 104,3 ± 22,9 frente a 91,1 ± 18,5 ms; p = 0,002), precisaron inotrópicos intravenosos (n = 77; 96,5 ± 20,5 frente a 90,1 ± 18,2 ms; p = 0,007) o sufrieron fibrilación auricular postoperatoria (n = 58; 98,2 ± 23,8 frente a 90,4 ± 17 ms; p = 0,018). El bloqueo de rama se asoció a mayor necesidad de balón de contrapulsación (el 29 frente al 12%; p = 0,012), inotrópicos (el 58 frente al 35%; p = 0,014) y mayor incidencia de inestabilidad hemodinámica (el 69 frente al 42%; p = 0,006). Tras el ajuste multivariable, los predictores de inestabilidad hemodinámica fueron la duración del QRS (odds ratio [OR] = 1,49; intervalo de confianza [IC] del 95%, 1,11-2; p = 0,007), la ausencia de injerto arterial (OR = 3,6; IC del 95%, 1,14-11,6; p = 0,029) y el tiempo de circulación extracorpórea (OR = 1,013; IC del 95%, 1,003-1,023; p = 0,013), con independencia de otros factores de riesgo. Conclusiones. El retraso de la conducción intraventricular o duración del intervalo QRS se asocia a mayor riesgo de inestabilidad hemodinámica durante el post-operatorio de cirugía coronaria (AU)

Introduction and objectives. The duration of the QRS interval measured by ECG is a marker of ventricular dysfunction and indicates a poor prognosis. Its value in patients undergoing coronary revascularization surgery has not been established.Methods. The study involved 203 consecutive patients (age 64±9 years, 74% male) scheduled for elective coronary surgery. The maximum QRS duration measured on a preoperative 12-lead ECG was recorded. Hemodynamic instability was defined as the occurrence of cardiac death, heart failure, or a need for intravenous inotropic drugs or intra-aortic balloon counterpulsation during the postoperative period.Results. The occurrence of hemodynamic instability (n=94, 46%) was associated with a longer preoperative QRS duration (97.5±21.14 ms vs 88.5±16.9 ms; P=.001). The QRS duration was also longer in patients who developed heart failure (n=23; 104.3±22.9 ms vs. 91.1±18.5 ms; P=.002), needed inotropic drugs (n=77; 96.5±20.5 ms vs. 90.1±18.2 ms; P=.007) or developed postoperative atrial (..) (AU)

[Usefulness of incremental atrial pacing for evaluating the effectiveness of the ablation of the slow perinodal pathway]. / Utilidad de la estimulación auricular progresiva para evaluar la efectividad de la ablación de la vía lenta perinodal.

INTRODUCTION AND OBJECTIVES: To study the usefulness of incremental atrial pacing for evaluating the effect of radiofrequency catheter ablation on slow pathway conduction in patients with atrioventricular (AV) nodal reentrant tachycardia. METHODS: A prospective study was carried out in patients either with (i.e., AV nodal reentrant tachycardia group) or without (i.e., control group) inducible AV nodal reentrant tachycardia who were referred for electrophysiologic study. Incremental atrial pacing involved gradually decreasing the pacing cycle length until the PR interval exceeded the R-R interval (i.e., PR>RR) or AV nodal block occurred. The presence of dual anterograde AV nodal physiology was assessed during programmed atrial stimulation using standard criteria. In the AV nodal reentrant tachycardia group, electrophysiologic study was repeated 30 minutes after successful catheter ablation. RESULTS: In the AV nodal reentrant tachycardia group (n=85), 52 patients (61%) exhibited dual AV nodal physiology during programmed atrial stimulation and 66 (78%) had a PR>RR during incremental atrial pacing. In the control group, the corresponding proportions were 10/56 (18%) and 7/56 (12%), respectively. After successful slow pathway catheter ablation (81/85), 37/81 exhibited dual AV nodal physiology during programmed atrial stimulation while 1/81 had a PR>RR during incremental atrial pacing. The positive predictive value of successful slow pathway ablation for the absence of a PR>RR was 98%. CONCLUSIONS: Incremental atrial pacing demonstrated that the PR interval exceeded the R-R interval in the majority of patients with inducible AV nodal reentrant tachycardia. This technique could provide a fast and simple way of evaluating the effect of radiofrequency catheter ablation on slow pathway conduction.

Utilidad de la estimulación auricular progresiva para evaluar la efectividad de la ablación de la vía lenta perinodal / Usefulness of incremental atrial pacing for evaluating the effectiveness of the ablation of the slow perinodal pathway

Introducción y objetivos. Estudiar la utilidad de la estimulación auricular progresiva para evaluar el efecto de la ablación con catéter sobre la conducción por vía lenta en pacientes con taquicardia por reentrada nodal común. Métodos. Estudio prospectivo en pacientes remitidos para estudio electrofisiológico en los que se indujo taquicardia por reentrada nodal común, empleando como grupo control a los pacientes en los que no se indujo. La estimulación auricular progresiva se practicó mediante la disminución paulatina del ciclo de estimulación hasta obtener un intervalo PR > RR o bloqueo auriculoventricular. Durante la estimulación auricular programada se evaluó la presencia de doble fisiología nodal siguiendo el criterio estandarizado. En el grupo en que se indujo taquicardia se repitió el estudio electrofisiológico 30 min después de la ablación. Resultados. En el grupo con taquicardia por reentrada nodal común (n = 85), 52 pacientes (61%) mostraron criterios de doble vía nodal durante la estimulación auricular programada y 66 (78%) mantenían PR > RR durante la estimulación auricular progresiva. En el grupo control, la incidencia de estos criterios fue de 10/56 (18%) y 7/56 (12%), respectivamente. Tras la ablación eficaz de vía lenta (81/85), 37 mostraban doble vía nodal durante la estimulación auricular programada y uno tenía PR > RR durante estimulación auricular progresiva (valor predictivo positivo de la ausencia de PR > RR para ablación eficaz de vía lenta del 98%). Conclusiones. La estimulación auricular progresiva muestra un intervalo PR > RR en la mayoría de los pacientes en los que se induce taquicardia por reentrada nodal común y puede emplearse como un método sencillo y rápido para evaluar el efecto de las aplicaciones de radiofrecuencia sobre la conducción por vía lenta

Introduction and objectives. To study the usefulness of incremental atrial pacing for evaluating the effect of radiofrequency catheter ablation on slow pathway conduction in patients with atrioventricular (AV) nodal reentrant tachycardia. Methods. A prospective study was carried out in patients either with (i.e., AV nodal reentrant tachycardia group) or without (i.e., control group) inducible AV nodal reentrant tachycardia who were referred for electrophysiologic study. Incremental atrial pacing involved gradually decreasing the pacing cycle length until the PR interval exceeded the R-R interval (i.e., PR>RR) or AV nodal block occurred. The presence of dual anterograde AV nodal physiology was assessed during programmed atrial stimulation using standard criteria. In the AV nodal reentrant tachycardia group, electrophysiologic study was repeated 30 minutes after successful catheter ablation. Results. In the AV nodal reentrant tachycardia group (n=85), 52 patients (61%) exhibited dual AV nodal physiology during programmed atrial stimulation and 66 (78%) had a PR>RR during incremental atrial pacing. In the control group, the corresponding proportions were 10/56 (18%) and 7/56 (12%), respectively. After successful slow pathway catheter ablation (81/85), 37/81 exhibited dual AV nodal physiology during programmed atrial stimulation while 1/81 had a PR>RR during incremental atrial pacing. The positive predictive value of successful slow pathway ablation for the absence of a PR>RR was 98%. Conclusions. Incremental atrial pacing demonstrated that the PR interval exceeded the R­R interval in the majority of patients with inducible AV nodal reentrant tachycardia. This technique could provide a fast and simple way of evaluating the effect of radiofrequency catheter ablation on slow pathway conduction

[Prognostic role of new biomarkers in off-pump coronary artery bypass surgery]. / Papel pronóstico de los nuevos biomarcadores en la cirugía coronaria sin circulación extracorpórea.

The value of biomarkers of myocardial damage or inflammation in off-pump coronary artery bypass (OPCAB) surgery has not yet been established. In a prospective study of 51 consecutive patients scheduled for elective OPCAB surgery, preoperative levels of troponin T, C-reactive protein, interleukin-6 and tumor necrosis factor-alpha were determined. The primary endpoint was the combination of cardiac death or acute myocardial infarction (AMI) within 30 days. Seven patients (14%) presented with an adverse event: three cardiac deaths and six AMIs. Univariate analysis identified the following adverse event predictors: renal failure (50% vs 11%, P=.028), left ventricular ejection fraction 0.10 ng/dL (43% vs 9%, P=.016), and EuroSCORE rating (7.6 [2.5] VS. 5.2 [2.6], P=.031). A preoperative troponin-T level > 0.10 ng/dL (P=.03) was the only independent adverse event predictor. No significant differences were found with biomarkers of inflammation (P.05). The presence of a preoperative troponin-T level > 0.10 ng/dL is associated with a higher risk of cardiac death or AMI in patients undergoing OPCAB surgery.

[Evolution of severe mitral regurgitation after optimization of pharmacological therapy in non-ischemic dilated cardiomyopathy]. / Evolución de la insuficiencia mitral severa tras optimización del tratamiento médico en la miocardiopatía dilatada no isquémica.

In dilated cardiomyopathy, severe functional mitral regurgitation (MR) is associated with a poor prognosis. In 112 consecutive clinically stable patients with non-ischemic dilated cardiomyopathy, echocardiography identified 15 (14%) patients who had severe MR (age, 53+/-12 years; 80% male; left ventricular ejection fraction, 26 +/- 8%). Existing medical treatment with ACE inhibitors and beta-blockers was increased up to the maximum tolerated doses. At 6 months, MR decreased by at least one grade in 13 (87%) patients (P =.001), as did the effective regurgitant orifice area (from 0.41 [0.05] mm2 to 0.20 [0.15] mm2; P.

Papel pronóstico de los nuevos biomarcadores en la cirugía coronaria sin circulación extracorpórea / Prognostic Role of new biomarkers in off-pump coronary artery bypass surgery

El papel de los marcadores de daño miocárdico e inflamación en la cirugía de revascularización coronaria (CRC) sin circulación extracorpórea (CEC) no ha sido establecido. Se realizó un estudio prospectivo de 51 pacientes consecutivos que recibieron CRC sin CEC. Se determinaron las concentraciones preoperatorias de troponina T, proteína C reactiva, interleucina-6 y factor de necrosis tumoral alfa. El evento primario fue el combinado de muerte cardiaca o infarto agudo de miocardio (IAM) a los 30 días. Un total de 7 pacientes (14%) presentaron eventos (3, muerte cardiaca y 6, IAM). En el análisis univariable fueron predictores la insuficiencia renal (el 50 frente al 11%; p = 0,028), la fracción de eyección del ventrículo izquierdo 0,10 ng/dl (el 43 frente al 9%; p = 0,016) y el EuroSCORE (7,6 +/- 2,5 frente a 5,2 +/- 2,6; p = 0,031). La troponina T > 0,10 ng/dl preoperatoria fue el único predictor independiente de eventos (p = 0,03). Los marcadores de inflamación no mostraron diferencias (p > 0,05). La presencia de troponina T preoperatoria > 0,10 ng/dl se asocia con un mayor riesgo de muerte o IAM en pacientes que reciben CRC sin CEC

The value of biomarkers of myocardial damage or inflammation in off-pump coronary artery bypass (OPCAB) surgery has not yet been established. In a prospective study of 51 consecutive patients scheduled for elective OPCAB surgery, preoperative levels of troponin T, C-reactive protein, interleukin-6 and tumor necrosis factor-alpha were determined. The primary endpoint was the combination of cardiac death or acute myocardial infarction (AMI) within 30 days. Seven patients (14%) presented with an adverse event: three cardiac deaths and six AMIs. Univariate analysis identified the following adverse event predictors: renal failure (50% vs 11%, P=.028), left ventricular ejection fraction 0.10 ng/dL (43% vs 9%, P=.016), and EuroSCORE rating (7.6 [2.5] VS. 5.2 [2.6], P=.031). A preoperative troponin-T level > 0.10 ng/dL (P=.03) was the only independent adverse event predictor. No significant differences were found with biomarkers of inflammation (P>.05). The presence of a preoperative troponin-T level > 0.10 ng/dL is associated with a higher risk of cardiac death or AMI in patients undergoing OPCAB surgery

Evolución de la insuficiencia mitral severa tras optimización del tratamiento médico en la miocardiopatía dilatada no isquémica / Evolution of severe mitral regurgitation after optimization of pharmacological therapy in non-ischemic dilated cardiomyopathy

En la miocardiopatía dilatada, la insuficiencia mitral (IM) funcional grave se asocia con una peor situación clínica y pronóstica. De 112 pacientes consecutivos con miocardiopatía dilatada no isquémica, 15 (14%) presentaban IM grave funcional por ecocardiografía (53 ± 12 años, 80% varones, FEVI 26 ± 8%). Se optimizó el tratamiento previo hasta dosis máximas toleradas de un inhibidor de la enzima de conversión de la angiotensina (IECA) y un bloqueador beta. A los 6 meses disminuyó el grado de insuficiencia en 13 pacientes (87%) (p = 0,001), el área del orificio regurgitante efectivo (0,41 ± 0,05 frente a 0,20 ± 0,15 mm²; p < 0,001) y del jet (13,6 ± 2,1 frente a 7,4 ± 4,5 cm²; p < 0,001). Estos cambios se correlacionaron con una mayor FEVI (26 ± 8 frente a 35 ± 10%; p = 0,009; r = 0,60, p = 0,01) y un menor volumen telesistólico (168 ± 46 frente 142 ± 72 ml; p = 0,04; r = 0,59, p = 0,02). Se observó una mejoría de la clase NYHA (2,7 ± 0,5 frente a 1,9 ± 0,7; p < 0,001). La IM funcional grave evolucionó hacia la mejoría tras la optimización máxima de IECA y bloqueadores beta, lo que parece correlacionar con una mejora de la función sistólica

In dilated cardiomyopathy, severe functional mitral regurgitation (MR) is associated with a poor prognosis. In 112 consecutive clinically stable patients with non-ischemic dilated cardiomyopathy, echocardiography identified 15 (14%) patients who had severe MR (age, 53±12 years; 80% male; left ventricular ejection fraction, 26 ± 8%). Existing medical treatment with ACE inhibitors and beta-blockers was increased up to the maximum tolerated doses. At 6 months, MR decreased by at least one grade in 13 (87%) patients (P =.001), as did the effective regurgitant orifice area (from 0.41 [0.05] mm² to 0.20 [0.15] mm²; P < .001) and the jet area (from 13.6 [2.1] cm² to 7.4 [4.5] cm²; P<.001). These changes correlated with an increase in left ventricular ejection fraction (from 26 [8]% to 35 [10]%, P=.009; r=0.60, P=.01) and a decrease in end-diastolic volume (from 168 [46] mL to 142 [72] mL, P=.04; r=0.59, P=.02). An improvement in New York Heart Association class was observed (from 2.7 [0.5] to 1.9 [0.7]; P < .001). The severity of functional MR decreased after medical treatment was maximized. The decrease correlated with improvements in left ventricular systolic function

[Usefulness of NTproBNP in the emergency management of patients with severe dyspnea and an uncertain heart failure diagnosis]. / Utilidad del NTproBNP en el manejo urgente del paciente con disnea severa y diagnóstico dudoso de insuficiencia cardíaca.

INTRODUCTION AND OBJECTIVES: Measurement of N-terminal pro-B-type natriuretic peptide (NTproBNP) helps in diagnosing heart failure (HF). The test's usefulness may be greatest in patients with severe dyspnea of uncertain origin. However, NTproBNP has not been evaluated specifically in this setting. PATIENTS AND METHOD: This prospective emergency department study included 70 patients with shortness of breath at rest as their chief complaint. In the attending physician's opinion, both HF and a non-cardiac cause were equally probable. Blinded NTproBNP measurement was carried out in blood samples collected on admission. Patients were monitored and their final diagnoses were based on clinical findings, therapeutic responses, and cardiac and noncardiac tests performed during hospitalization. RESULTS: The NTproBNP level was higher in the 49 patients (70%) with a final diagnosis of HF (P = .006); the area under the ROC curve was 0.72 (0.60-0.82). The optimum diagnostic cut-off value was 900 pg/mL, which had an accuracy of 87%, a sensitivity of 98%, and a negative predictive value of 92%. The NTproBNP level was significantly higher in the 6 patients (9%) who died during hospitalization (P = .009); the area under the ROC curve was 0.87 (0.76-0.93) and the optimum cut-off value for predicting death was 5500 pg/mL, which had an accuracy of 77%, a sensitivity of 100%, and a positive likelihood ratio of 4.2. CONCLUSIONS: In patients with severe dyspnea and an uncertain diagnosis of HF, an NTproBNP level < 900 pg/mL helps exclude the presence of HF, whereas a NTproBNP level > 5500 pg/mL identifies patients at an increased risk of death.

Utilidad del NTproBNP en el manejo urgente del paciente con disnea severa y diagnóstico dudoso de insuficiencia cardíaca / Usefulness of NTproBNP in the emergency management of patients with severe dyspnea and an uncertain heart failure diagnosis

Introducción y objetivos. El NTproBNP ayuda a identificar a los pacientes con insuficiencia cardíaca. Su utilidad podría ser máxima en pacientes con disnea severa de origen incierto; sin embargo, esta población no ha sido específicamente evaluada. Pacientes y método. Estudio prospectivo de 70 pacientes que acudieron a urgencias refiriendo disnea de reposo, cuyo diagnóstico clínico inicial fue establecido como dudoso, con probabilidad intermedia de insuficiencia cardíaca. A la llegada a urgencias se extrajeron las muestras analíticas y se determinó el valor de NTproBNP de forma ciega. Los pacientes fueron controlados y el diagnóstico final se estableció sobre la base de los hallazgos clínicos, la respuesta al tratamiento y las pruebas practicadas durante el curso hospitalario. Resultados. El NTproBNP fue mayor en los 49 pacientes (70%) con un diagnóstico final de insuficiencia cardíaca (p = 0,006), obteniendo un área bajo la curva ROC de 0,72 (0,60-0,82). El valor de corte diagnóstico óptimo fue 900 pg/ml, con una precisión del 87%, una sensibilidad del 98% y un valor predictivo negativo del 92%. En los 6 pacientes (9%) fallecidos durante la hospitalización, el NTproBNP fue significativamente mayor (p = 0,009), con un área bajo la curva ROC de 0,87 (0,76-0,93) y un valor de corte pronóstico óptimo de 5.500 pg/ml, con una precisión del 77%, una sensibilidad del 100% y una razón de probabilidad positiva de 4,2. Conclusiones. En una población con disnea severa que acude a urgencias con diagnóstico dudoso de insuficiencia cardíaca, un valor de NTproBNP 5.500 pg/ml identifica a los pacientes con un mayor riesgo de muerte hospitalaria

Introduction and objectives. Measurement of N-terminal pro-B-type natriuretic peptide (NTproBNP) helps in diagnosing heart failure (HF). The test's usefulness may be greatest in patients with severe dyspnea of uncertain origin. However, NTproBNP has not been evaluated specifically in this setting. Patients and method. This prospective emergency department study included 70 patients with shortness of breath at rest as their chief complaint. In the attending physician's opinion, both HF and a non-cardiac cause were equally probable. Blinded NTproBNP measurement was carried out in blood samples collected on admission. Patients were monitored and their final diagnoses were based on clinical findings, therapeutic responses, and cardiac and noncardiac tests performed during hospitalization. Results. The NTproBNP level was higher in the 49 patients (70%) with a final diagnosis of HF (P=.006); the area under the ROC curve was 0.72 (0.60-0.82). The optimum diagnostic cut-off value was 900 pg/mL, which had an accuracy of 87%, a sensitivity of 98%, and a negative predictive value of 92%. The NTproBNP level was significantly higher in the 6 patients (9%) who died during hospitalization (P=.009); the area under the ROC curve was 0.87 (0.76-0.93) and the optimum cut-off value for predicting death was 5500 pg/mL, which had an accuracy of 77%, a sensitivity of 100%, and a positive likelihood ratio of 4.2. Conclusions. In patients with severe dyspnea and an uncertain diagnosis of HF, an NTproBNP level 5500 pg/mL identifies patients at an increased risk of death

[Functional assessment of patients with hypertrophic cardiomyopathy by maximal oxygen consumption]. / Evaluación funcional de los pacientes con miocardiopatía hipertrófica mediante análisis del consumo de oxígeno máximo.

INTRODUCTION AND OBJECTIVES: Differences between anatomical severity and clinical manifestations are frequent in patients with hypertrophic cardiomyopathy. Our objective was to assess functional capacity in a consecutive group of patients with hypertrophic cardiomyopathy measuring exercise aerobic parameters, as well as clinical and echocardiographic variables. PATIENTS AND METHOD: We studied 98 consecutive patients with hypertrophic cardiomyopathy. All patients underwent both echocardiographic and cardiopulmonary exercise testing. The control group consisted of 22 untrained persons. We studied exercise capacity by analyzing maximal oxygen consumption and aerobic functional capacity, among other variables. RESULTS: Patients with hypertrophic cardiomyopathy attained significantly lower maximal oxygen consumption values than controls (24.1 5.9 vs 36.4 5.9 ml/kg/min; p = 0.0001). Maximal aerobic capacity was significantly different among patients with NYHA functional capacity class I, II or III (78.9 13.5%; 71.9 14.7%; 63.9 15.7%; p = 0.009). However, considerable overlap was found between groups in maximal aerobic capacity. Functional impairment was greater in patients with left ventricular thickness > 20 mm, ejection fraction < 50%, left atrial dimension > 45 mm and pseudonormal or restrictive transmitral flow pattern. CONCLUSIONS: Patients with hypertrophic cardiomyopathy show significant functional impairment, which is difficult to detect from their clinical manifestations. Optimal assessment requires cardiopulmonary exercise testing.

Evaluación funcional de los pacientes con miocardiopatía hipertrófica mediante análisis del consumo de oxígeno máximo / Functional assessment of patients with hypertrophic cardiomyopathy by maximal oxygen consumption

Introducción y objetivos. En pacientes con miocardiopatía hipertrófica, frecuentemente encontramos discrepancias entre la gravedad de la afección anatómica y la expresión clínica. El objetivo de nuestro estudio fue evaluar la repercusión funcional de la enfermedad mediante el análisis de gases respirados, teniendo en cuenta variables clínicas y ecocardiográficas. Pacientes y método. Estudiamos de forma consecutiva a 98 pacientes con miocardiopatía hipertrófica. A todos ellos se les realizó un estudio ecocardiográfico y un estudio ergométrico con análisis de los gases respirados. El grupo control estaba formado por 22 sujetos sanos, no entrenados. Como parámetros ventilatorios se estudiaron, entre otros, el consumo de oxígeno máximo y la capacidad funcional aeróbica. Resultados. El consumo de oxígeno máximo alcanzado por los pacientes fue significativamente menor que el alcanzado por los controles (24,1 ñ 5,9 frente a 36,4 ñ 5,9 ml/kg/min; p = 0,0001). Al analizar los datos de la capacidad funcional aeróbica, encontramos diferencias significativas según el paciente tuviera un grado funcional I, II o III de la New York Heart Association (NYHA) (78,9 ñ 13,5 por ciento; 71,9 ñ 14,7 por ciento; 63,9 ñ 15,7 por ciento; p = 0,009). Sin embargo, fue notable la presencia de una importante superposición entre los grupos. Los subgrupos más afectados fueron los pacientes con hipertrofia superior a 20 mm, fracción de eyección 45 mm y los que presentaban un patrón de flujo mitral seudonormal o restrictivo. Conclusiones. Los pacientes con miocardiopatía hipertrófica presentan una importante limitación al ejercicio que difícilmente es valorable mediante la expresión clínica de la enfermedad. Una correcta valoración individual requiere el análisis del consumo de oxígeno máximo (AU)

[Addition of an angiotensin II receptor blocker to maximal dose of ACE inhibitors in heart failure]. / Adición de un ARAII al tratamiento con dosis máximas de IECA en la insuficiencia cardíaca.

In heart failure, the benefits of adding angiotensin-receptor blockade to ACE inhibitors have been studied only with submaximal doses of ACE inhibitors. We included 20 patients (LVEF 24 7%, NYHA II-III), with no clinical or therapeutic variations in the previous three months, who were receiving maximal doses of ACE inhibitors. We added losartan 50 mg once a day. At six months, SBP decreased (115 8 vs. 106 9 mmHg; p = 0.001), LVEF increased (24.4 7 vs. 34.1 7%; p < 0.001), ventricular end-diastolic volumes decreased (220 58 vs 190 46 ml; p = 0.007), and SPAP decreased (43 8 vs. 35 7 mmHg; p < 0.001). Seven patients improved one degree on the NYHA scale (p = 0.004), but VO2max did not change (20.8 5.2 vs. 21.8 5.0 ml/kg/min, p = 0.120). Plasma levels of norepinephrine, at rest and maximal exercise, brain natriuretic peptide, and renin were similar. After maximum ACE inhibitor doses, the addition of losartan is safe and associated with an improvement in ventricular function and NYHA functional class, but with no change in neurohormonal status.