Obstructive sleep apnea (OSA) is the most common type of sleep apnea caused by a complete or partial obstruction of the upper airway.If the symptoms are also present in the daytime, it is referred to as obstructive sleep apnea syndrome. Multiple clinical reports have shown an association between OSA and heart failure. In patients with OSA, during the apneic events, substantial negative intrathoracic pressure develops due to continuous respiratory efforts against a partially or totally obstructed upper airway. This in turn causes a dramatic increase in after load resulting in decreased left ventricular stroke volume. In addition to these mechanical interactions, nocturnal myocardial ischemia may contribute to episodes of acute heart failure in patients with OSA. The aim of this study was to assess the changes in electrocardiographic parameters in proven obstructive sleep apnea patients to predict impending heart failure in a resource-scarce situation. A total of 30 proven OSA patients were included in the study and their electrocardiographic parameters were compared with the Apnea-Hyponea index derived from the polysomnography test results. In this study, the most common electrocardiographic markers seen were Prolonged PR interval(63.3%), Abnormal P wave (66.6%), Left ventricular hypertrophy(46.6%), Left axis deviation (30%), Prolonged QTc interval(46.6%). Studies have shown that prolonged QRS duration, left‐axis deviation, prolonged QT interval, abnormal QRS‐T axis, left ventricular hypertrophy, and left bundle‐branch block, abnormal P‐wave axis, are associated with Heart failure. Hence this study shows that the at risk OSA population can be risk stratified for impending heart failure using low‐cost, noninvasive cardiac assessment tools like Electrocardiographs in rresource-scarce situations.

Keywords: Obstructive sleep apnea, Apnea hypopnea index, P-wave duration, QRS duration, QT prolongation.

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Dr Aravind Kumar.V

Post Graduate, Department of Medicine, Sri Manakula Vinayagar Medical College and Hospital, Pondicherry, India