External Counterpulsation Therapy for Patients with Mild Cognitive Impairment

Research Article

Austin J Clin Med. 2016; 3(2): 1029.

External Counterpulsation Therapy for Patients with Mild Cognitive Impairment

Moriarty PM1*, Badawi AH1, Lepping RJ2, Nolte B1, Tye SL1, Burns JM3, Bishara M4, Dutton JA1, Sehar N1, Denney LK1, Tennant HM1 and Brooks WB2

1Division of Clinical Pharmacology, The University of Kansas Medical Center, Kansas City, KS, USA

2Hoglund Brain Imaging Center, The University of Kansas Medical Center, Kansas City, KS, USA

3Alzheimer’s Disease Center, The University of Kansas Medical Center, Kansas City, KS, USA

4Department of Ophthalmology, The University of Kansas Medical Center, Kansas City, KS, USA

*Corresponding author: Moriarty PM, Division of Clinical Pharmacology, University of Kansas Medical Center, 3901 Rainbow Blvd, Mail Stop 3008, Kansas City, USA

Received: September 16, 2016; Accepted: October 07, 2016; Published: October 10, 2016

Abstract

The development of vascular dementia and Alzheimer’s Disease (AD) share an association with hemodynamic risk factors. Physical exercise improves cardiac output, which in turn increases Cerebral Blood Flow (CBF) and may improve cognitive function. Unfortunately, patients with signs of dementia are not always able to exercise, due to cognitive or physical decline. The Enhanced External Counterpulsation (EECP) therapy system is a non-invasive device used for patients with chronic angina and mild heart failure. This study evaluated the CBF changes in patients (n=4) with Mild Cognitive Impairment (MCI) after 35 one hour sessions of EECP therapy over 7 weeks. EECP therapy improves CBF in certain brain regions and there is evidence that these effects may persist for 6 months post-treatment. Cognitive function appears to be correlated with CBF rate in the hippocampus and precuneus. Although this study is small, its results are promising and support the need for a larger randomized controlled trial.

Keywords: External Counterpulsation; Mild cognitive impairment; Dementia; Alzheimer’s disease; Cerebral blood flow

Abbreviations

AD: Alzheimer’s Disease; CBF: Cerebral Blood Flow; EECP: Enhanced External Counterpulsation; MCI: Mild Cognitive Impairment; CHF: Congestive Heart Failure; MRI: Magnetic Resonance Imaging; CDR: Clinical Dementia Rating; ADAS-cog: AD Assessment Scale-Cognitive Subscale; ROI: Regions of Interest

Introduction

There is a strong correlation between Alzheimer’s disease (AD) and poor Cerebral Blood Flow (CBF) [1]. Cognitive decline occurs naturally with age, however a more severe decline, as in Mild Cognitive Impairment (MCI), is a precursors to AD. Observational studies have shown that the treatment of vascular risk factors including: hypertension, diabetes, cerebrovascular diseases, and hypercholesterolemia, decrease the risk of dementia progression [2,3]. Physical exercise is the most basic and efficient way to improve blood flow [4]. Physical exercise has been shown to increase cardiac output, which in turn leads to an increase in CBF [5]. Wang et al and Varghese et al. have shown that elderly patients who partake in physical activity are less likely to develop dementia and experience cognitive decline [6,7]. Due to cognitive or physical decline, patients with signs of dementia are not always able to exercise. The Enhanced External Counterpulsation (EECP) therapy system is a non-invasive device. Traditionally, EECP is used to treat patients with chronic angina and Congestive Heart Failure (CHF) by increasing cardiac output and reducing the workload of the heart. EECP increases cardiac output by improving systolic unloading and venous return [8]. Patients with CHF have an increased risk of cognitive dysfunction presumably because of decreased CBF [9]. In a study done by Kozdag et al. EECP therapy resulted in improvement in all cognitive domains except visual and verbal memory tests in patients with CHF [9]. Thus, EECP may be used as an exercise alternative to increase CBF. The effects of EECP may act similarly to exercise therapy and are explored for patients with MCI in this study. Our objective was to evaluate CBF changes as well as changes in cognition in patients with MCI and no CHF or angina after 35 one hour sessions of EECP therapy. This was performed on a small sample for safety and feasibility in a cognitively impaired population. Future and larger outcome trials may be modeled after this small study.

Methods

Four patients, ages 64-74, were screened and selected from the University of Kansas Medical Center, with Clinical Dementia Rating (CDR) scores of 0.5, indicating MCI. Each study patient gave informed consent and understood the study rationale.

Patients received standard EECP (Figure 1, Vasomedical, Westbury, NY) therapy, consisting of 35 one hour treatments over a seven week period (5 treatments per week). The EECP machine contains 3 paired pressure cuffs wrapped around the calves and the lower and upper thighs. These cuffs are inflated sequentially (applying 250-300 mmHg of external pressure) starting from the calves during diastole and rapidly deflated during systole. The compressions and relaxations of the cuffs are paired with the R wave of the heart during the cardiac cycle. The cardiac cycles is monitored with a microprocessor that coordinate the inflation and deflation of the cuff with each heart beat via electrocardiogram interpretation.