Abstract 2909: Diastolic Function is Abnormal in Subjects with Low Aortic Compliance.
INTRODUCTION: Heart failure with normal ejection fraction (HFNEF) or diastolic heart failure is responsible for nearly 50% of all CHF admissions. Aortic compliance is noted to be reduced in patients with HFNEF and may contribute to congestive heart failure via vascular-ventricular coupling. We sought to determine the relationship between aortic compliance and diastolic function in Dallas Heart Study (DHS) population.
HYPOTHESIS: We assessed the hypothesis that low aortic compliance is associated with abnormal diastolic function of the left ventricle.
METHOD: We examined 104 subjects of the total 3,386 cohort of the DHS, a multi-ethnic, population based sample of adults aged 30 – 65 years. We first identified two subject groups:
48 healthy subjects without any medical conditions and with normal aortic compliance and
58 subjects with abnormal aortic compliance.
Diastolic function was determined by early peak filling rate by tracing endocardial borders manually to measure LV cavity. Papillary muscles were excluded in the calculation of LV cavity. Aortic compliance was based on MRI measurements. MRI was performed using two comparable 1.5 Tesla MRI systems (Philips Medical systems). Briefly, short-axis breath-hold, ECG-gated cine MR images were obtained from the apex to the base of the left ventricle using the following parameters: 6mm slice, 4mm gap, field of view of 36 – 40, and temporal resolution of 40 msec.
RESULTS: Subjects with normal compliance had an increased peak filling rate (358 +/- 95) when compared to patients with abnormal compliance (261 +/- 81). This difference persisted when peak filling rate was indexed to the end diastolic volume (normal AC, 4.51 +/- 1.0 vs low compliance, 3.29 +/-0.83). T-test between the groups confirmed the significant difference with a p value of < 0.001.
CONCLUSION: Subjects with abnormal aortic compliance have abnormal diastolic function when compared to normal, healthy subjects in the randomized, population based sample of the DHS.