BACKGROUND: Patients with hypertension (HTN) have been known to show increased aortic stiffness and those are related with high blood pressure. However, there is rare study about the relationship between aortic stiffness and the left ventricular (LV) end-diastolic pressure and diastolic dysfunction. In this study, we evaluated the relation between aortic stiffness and LV diastolic dysfunction in patients with HTN. METHODS: Patients were divided into four groups according to the degree of E/E��� and HTN. Group I (n=50) is composed of the patients with normal E/E���(���8) without HTN, group II (n=51) is composed of those with elevated E/E���(>8) without HTN, group III (n=29) is composed of the patients with normal E/E���(���8) with HTN, and group IV (n=104) is composed of the patients with elevated E/E���(>8) with HTN. Aortic diameters were measured by using M-mode at a level that is 3cm above the aortic valve. Aortic distensibility (AD) was calculated by using the formula; 2 x (pulsatile change in aortic diameter) / (diastolic aortic diameter) x (aortic pulse pressure). And brachial-ankle pulse wave velocity (baPWV) was measured. RESULTS: A total 234 patients (103 men) were enrolled and the mean age was 47.9짹15.1 years. The mean value of AD was lower in group III compared to group I (3.8짹2.0 vs. 5.1짹2.4, p=0.03). Group IV showed lower AD compared to group II (3.0짹1.8 vs. 4.3짹2.4, p < 0.01). However, mean AD was not significantly different between group I and group II, and between group III and group IV. Group III showed higher baPWV compared to group I (1422짹182 vs. 1177짹177 cm/sec, p<0.01) and group IV showed higher baPWV compared to group II (1512짹260 vs. 1267짹230 cm/sec, p<0.01). However, mean baPWV were comparable between group I and group II and between group III and group IV. AD showed negative correlation with baPWV in groups with lower E/E��� (r=-0.44, p=0.01 in group I, r=-0.50, p=0.04 in group III). Group I showed significant higher E/A ratio (1.90짹2.51 vs 1.19짹0.44, p=0.021) and lower left atrial (LA) volume index (19.4짹5.4 mm3/m2 vs 26.3짹8.3 mm3/m2 , p=0.012) compared to group II. But group III and IV (patients with HTN) showed comparable E/A ratio (1.06짹0.27 vs 0.93짹0.32, p=1.00) and LA volume index (26.2짹8.1 mm3/m2 vs 29.6짹8.4 mm3/m2, p=0.671) CONCLUSIONS: Patients with hypertension showed lower AD and higher baPWV compared to those with normal blood pressure, independent of E/E��� ratio. Negative correlation between AD and baPWV was present only in the condition of lower E/E���, regardless of HTN. These results suggest that HTN and higher LVEDP may influence the aortic distensibility.