Nuria Grau1, Victor Bazan2, Mohamed Kallouchi1, Diego Rodriguez1, Cristina Estirado1, Maria Isabel Corral3, Maria Teresa Valls3, Pablo Ramos3, Carles Sanjuas1, Miquel Felez1, Ermengol Valles3, Begoña Benito3, Joaquim Gea1, Jordi Bruguera-Cortada3, Julio Martí-Almor3. 1. Unidad de Trastornos Respiratorios del Sueño, Servicio de Neumología, CIBERES, Hospital del Mar, Universitat Autònoma de Barcelona, Barcelona, España. 2. Unidad de Electrofisiología y Arritmias, Servicio de Cardiología, Grupo de Investigación Biomédica en Enfermedades del Corazón, IMIM (Instituto Hospital del Mar de Investigaciones Médicas), Hospital del Mar, Universitat Autònoma de Barcelona, Barcelona, España. Electronic address: victorbazang@yahoo.com. 3. Unidad de Electrofisiología y Arritmias, Servicio de Cardiología, Grupo de Investigación Biomédica en Enfermedades del Corazón, IMIM (Instituto Hospital del Mar de Investigaciones Médicas), Hospital del Mar, Universitat Autònoma de Barcelona, Barcelona, España.
Abstract
INTRODUCTION: Autonomic dysfunction can alter heart rate variability and increase the incidence of arrhythmia. We analyzed the impact of continuous positive airway pressure (CPAP) on this pathophysiological phenomenon in patients with severe sleep apnea-hypopnea syndrome. METHODS: Consecutive patients with recently diagnosed severe sleep apnea-hypopnea syndrome were prospectively considered for inclusion. Incidence of arrhythmia and heart rate variability (recorded on a 24-hour Holter monitoring device) were analyzed before starting CPAP therapy and 1 year thereafter. RESULTS: A total of 26 patients were included in the study. CPAP was administered for 6.6 ± 1.8 hours during Holter monitoring. After starting CPAP, we observed a marginally significant reduction in mean HR (80 ± 9 to 77 ± 11 bpm, p=.05). CPAP was associated with partial modulation (only during waking hours) of r-MSSD (p=.047) and HF (p=.025) parasympathetic parameters and LF (p=.049) sympathetic modulation parameters. None of these parameters returned completely to normal levels (p<.001). The number of unsustained episodes of atrial tachycardia diminished (p=.024), but no clear effect on other arrhythmias was observed. CONCLUSIONS: CPAP therapy only partially improves heart rate variability, and exclusively during waking hours, and reduces incidence of atrial tachycardia, both of which can influence cardiovascular morbidity and mortality in sleep apnea-hypopnea syndrome patients.
INTRODUCTION: Autonomic dysfunction can alter heart rate variability and increase the incidence of arrhythmia. We analyzed the impact of continuous positive airway pressure (CPAP) on this pathophysiological phenomenon in patients with severe sleep apnea-hypopnea syndrome. METHODS: Consecutive patients with recently diagnosed severe sleep apnea-hypopnea syndrome were prospectively considered for inclusion. Incidence of arrhythmia and heart rate variability (recorded on a 24-hour Holter monitoring device) were analyzed before starting CPAP therapy and 1 year thereafter. RESULTS: A total of 26 patients were included in the study. CPAP was administered for 6.6 ± 1.8 hours during Holter monitoring. After starting CPAP, we observed a marginally significant reduction in mean HR (80 ± 9 to 77 ± 11 bpm, p=.05). CPAP was associated with partial modulation (only during waking hours) of r-MSSD (p=.047) and HF (p=.025) parasympathetic parameters and LF (p=.049) sympathetic modulation parameters. None of these parameters returned completely to normal levels (p<.001). The number of unsustained episodes of atrial tachycardia diminished (p=.024), but no clear effect on other arrhythmias was observed. CONCLUSIONS: CPAP therapy only partially improves heart rate variability, and exclusively during waking hours, and reduces incidence of atrial tachycardia, both of which can influence cardiovascular morbidity and mortality in sleep apnea-hypopnea syndromepatients.