Effect of Atlas Cedarwood Essential Oil Aromatherapy on Sleep Quality Among Patients With Coronary Heart Disease

The primary aim is testing the effect of Atlas cedar wood essential oil aromatherapy on sleep quality of patients after CHD. The secondary aim is estimating the prevalence of sleep-wake disturbances (difficulty falling asleep, staying asleep, inadequate sleep duration, dissatisfaction with a sleep and excessive daytime sleepiness) among recruited CHD patients. \- data were collected by two phase: * phase one: sleep quality of recruited CHD patients, who were admitted for undergoing coronary angiography electively, were assessed using Pittsburg Sleep Quality Index (PSQI). CHD participants who were reported poor sleep quality (=\>5) in PSQI score will randomly allocated by toss either to intervention or control group. * Phase two: 1. Intervention group received an atlas cedar wood aromatherapy for five consecutive nights. 2. Control group received no intervention. 3. Sleep quality of both group participants re-assessed at second day and six day of recruitment, respectively, using PSQI.