RESUMO
RESUMEN Objetivos: Evaluar la prevalencia del déficit de hierro en hipertensión pulmonar y compararlo con otras poblaciones de pacientes. Establecer su valor pronóstico. Material y métodos: Estudio prospectivo, observacional. Se midieron parámetros de hierro sérico en pacientes consecutivos con diagnóstico de hipertensión pulmonar. Se compararon con pacientes con insuficiencia cardíaca y con controles sanos. Se buscó correlación entre los valores séricos de hierro y la clase funcional, la distancia recorrida en TC6M y el NT-proBNP. Resultados: Participaron 107 pacientes: 60 con hipertensión pulmonar, 26 con insuficiencia cardíaca y 21 controles sanos. El déficit de hierro fue del 78,3% en los pacientes con hipertensión pulmonar; del 45,8%, en aquellos que presentaban insuficiencia cardíaca; y del 23,8% (p < 0,001) en los controles sanos. La prevalencia de anemia resultó del 25% en los pacientes con hipertensión pulmonar; del 26,9% en los que padecían insuficiencia cardíaca; y del 19% (p < 0,8) en los controles sanos. En el subgrupo de pacientes en clase funcional I-II, la prevalencia de DFe fue del 78% en los pacientes con hipertensión pulmonar vs. el 43,5% (p < 0,005) en los que tenían insuficiencia cardíaca, y la anemia resultó del 17,1%% vs. el 28%% (p < 0,2). Se halló correlación significativa entre ferremia y saturación de transferrina con distancia caminada en TC6M (r: 0,35; p < 0,01 y r: 0,34; p < 0,01) y no hubo correlación para ferritina y transferrina. No se encontró significancia estadística entre déficit de hierro y clase funcional o NT-proBNP. Conclusiones: El déficit de hierro en la hipertensión arterial es altamente prevalente y superior al observado en la insuficiencia cardíaca y en los sujetos control, y no se establece relación con prevalencia de anemia, la cual fue similar en los tres grupos. El hierro sérico tiene una clara relación con la distancia caminada, no así con clase funcional, lo que, tal vez, obedezca al bajo número de pacientes.
ABSTRACT Objective: The aim of this study was to assess the prevalence of iron deficiency in pulmonary hypertension, to compare it with other patient populations and to establish its prognostic value. Methods: This was a prospective, observational study. Serum iron parameters were measured in consecutive patients diagnosed with pulmonary hypertension and compared with heart failure patients and healthy controls. A correlation was sought between serum iron levels and functional class, distance walked in the 6-minute walk test and NT-proBNP. Results: A total of 107 patients were included in the study: 60 with pulmonary hypertension, 26 with heart failure and 21 healthy controls. Iron deficiency was 78.3% in patients with pulmonary hypertension, 45.8% in those with heart failure and 23.8% in healthy controls (p<0.001). The prevalence of anemia was 25% in pulmonary hypertension, 26.9% in heart failure and 19% in healthy controls (p<0.8). In patients with functional class I-II, iron deficiency was: 78% in pulmonary hypertension vs. 43.5% in heart failure (p<0.005), and anemia was 17.1% vs. 28%, respectively (p<0.2). A significant correlation was found between serum iron and transferrin saturation with the distance walked in the 6-minute walk test (r: 0.35; p<0.01 and r: 0.34; p<0.01, respectively) and no correlation was found for transferrin and ferritin. Also, no significant correlation was found between iron deficiency and functional class or NT-proBNP. Conclusions: Iron deficiency is highly prevalent in pulmonary hypertension, and superior to that found in heart failure patients and healthy controls. No relationship was established with anemia, which was similar in the three groups. Serum iron is clearly related with the distance walked, but not with functional class, a result which may be attributed to the limited number of patients.
RESUMO
BACKGROUND: The respiratory sinus arrhythmia is the most common cardiac arrhythmia. It consists of phasic variations of sinus cycle length produced by an autonomic reflex, and is characterized by increased heart rate during inspiration and decline in expiration. This phenomenon is due to a reduction of the parasympathetic tone during inspiration, causing a rise in the heart rate, while during expiration the opposite phenomenon occurs. This arrhythmia is more frequent in young adults, although it can also be seen in any age group. METHODS AND RESULTS: We report the case of a 46-year-old female, who was transferred to our institution because of dizziness and loss of balance reported during deep inspiration, associated with sinus bradycardia and atrioventricular block.
