Effect of Enhanced External Counter Pulsation Treatment on Aortic Blood Pressure, Arterial Stiffness and Ejection Fraction in Patients with Coronary Artery Disease

Abstract

Introduction: Enhanced External Counter Pulsation (EECP) is a non-invasive treatment option for patients with Coronary Artery Disease (CAD). The treatment has shown to augment diastolic pressure and reduce Left Ventricular (LV) after-load by reducing systemic vascular resistance. The effect of EECP in standard brachial blood pressure and central haemodynamic parameters are not known. Aim: We hypothesized that EECP may have differential effect in CAD patients with low systolic blood pressure when compared to normal systolic pressure and the mechanism underlying this differential effect may be due to improvement in LV function. Materials and Methods: A total of 72 consecutive patients who underwent EECP treatment for symptomatic CAD with LV dysfunction were divided into two groups based on cut-off value of 100mmHg for systolic blood pressure. First group had patients with brachial systolic blood pressure of >100mmHg and second group had patients with brachial systolic blood pressure of ≤100mmHg. We measured central aortic systolic pressure, pulse pressure, augmentation index and augmentation pressure by SphygmoCor device and Ejection Fraction (EF) was measured by echo-cardiography. All these measurements were carried out prior to and after completion of 35 days of EECP sessions. Results: Central systolic pressure, brachial systolic pressure, aortic pulse pressure, augmentation pressure and augmentation index significantly decreased in patients with normal brachial systolic pressure with baseline moderate LV dysfunction. Brachial systolic, aortic systolic and aortic pulse pressure significantly increased with no change in augmentation index and pressure is observed in patients with baseline severe LV dysfunction associated with low systolic pressure post EECP treatment. Conclusion: EECP treatment has haemodynamically favourable differential effect in normal and low brachial systolic pressure and this is mainly driven by improvement in LV function in patients with symptomatic CAD with LV dysfunction.

Keywords

• augmentation index
• central systolic pressure
• left ventricular dysfunction