Evaluation of Proximal Aortic Elastic Properties in Non-Ischemic Dilated Cardiomyopathy by Trans-Thoracic Echocardiography: A Case-Control Study

Background: Stiffening of the large vessels, especially aorta, plays a significant role in increasing the left ventricular work and aggravating the cardiovascular diseases by attenuating the vascular wall distensibility and its buffering effect.

Objectives: This study aimed to compare the stiffness of proximal aorta in the patients with established diagnosis of Non-Ischemic Dilated Cardiomyopathy (NIDC) and the normal population.

Patients and Methods: This case-control study aimed to compare 50 patients with established diagnosis of NIDC and 50 individuals with no history of significant cardiovascular diseases in the outpatient echocardiography clinics affiliated to Shiraz University of Medical Sciences, Shiraz, Iran during a three-month period in 2011. The patients with aortic valve disorders, coronary artery disease, congenital heart disease, diabetes mellitus, hypertension, and renal failure were excluded from the study. Stiffness indices were determined using the data gathered via echocardiography (left ventricular ejection fraction, end-systolic and end-diastolic volumes, and internal aortic diameter) and blood pressure measurement. Ordinal and quantitative data were analyzed by Chi-square and independent T-test, respectively using the SPSS statistical software, version 16.0. Besides, P < 0.05 was considered as statistically significant.

Results: The results of this study revealed significantly lower aortic strain (0.05 ± 0.02 in the NIDC patients versus 0.20 ± 0.46 in the controls, P < 0.001) and brachial pulse pressure (40.50 ± 9.00 in the NIDC patients versus 45.90 ± 8.08 in the controls, P < 0.001) in the NIDC patients.

Conclusions: Aortic stiffness is capable of deteriorating the cardiovascular function by augmenting the afterload. Thus, it should be seriously considered as an issue while approaching NIDC patients since they demonstrate lower aortic distensibility.