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Published on: January 20, 2023
Acute Hemodynamic Responses to Enhanced External Counterpulsation in Patients With Coronary Artery Disease
Yahui Zhang1,2,3, Ziqi Chen1,2, Zhouming Mai4
1Department of Cardiology, The Eighth Affiliated Hospital, Sun Yat-sen University, Shenzhen, China.
Insights
Enhanced external counterpulsation (EECP) improves vascular function in coronary artery disease (CAD) patients, increasing inner diameter and flow rate. EECP shows sex-specific effects on blood flow characteristics in carotid and peripheral arteries.
Area of Science:
- Cardiovascular Physiology
- Non-invasive Hemodynamics
- Medical Device Technology
Background:
- Enhanced external counterpulsation (EECP) is a non-invasive therapy aimed at improving coronary blood flow in patients with coronary artery disease (CAD).
- The immediate vascular and hemodynamic effects of EECP on conduit arteries require further investigation.
- Understanding these acute responses is crucial for optimizing EECP protocols and patient outcomes.
Purpose of the Study:
- To evaluate the acute changes in vascular and blood flow parameters in common carotid, brachial, and femoral arteries during and immediately after EECP in patients with CAD.
- To compare these responses between CAD patients and healthy controls.
- To explore potential sex-based differences in vascular responses to EECP.
Main Methods:
- Forty-two CAD patients and 21 healthy controls underwent 45 minutes of EECP.
- Color Doppler ultrasound was used to measure peak systolic velocity (PSV), end-diastolic velocity (EDV), inner diameter (ID), resistance index (RI), and flow rate (FR) in the left carotid, right carotid, right brachial, and right femoral arteries.
- Measurements were taken before, during, and immediately after EECP.
Main Results:
- During EECP, both groups showed decreased EDV and increased RI in carotid arteries. CAD patients experienced increased LC flow rate and reduced PSV.
- Immediately after EECP, CAD patients exhibited increased ID in the left carotid, right brachial, and right femoral arteries compared to baseline and controls.
- Subgroup analysis revealed significant sex-based differences in FR, PSV, and RI responses during and after EECP, particularly in carotid and brachial arteries.
Conclusions:
- EECP induces distinct vascular and blood flow alterations in carotid and peripheral arteries, with more pronounced effects in the carotid arteries.
- Beneficial effects on inner diameter, blood flow velocity, RI, and FR were observed post-EECP exclusively in CAD patients.
- EECP demonstrated sex-specific hemodynamic responses, with brachial artery flow improvements in males and carotid artery changes in females.
Abstract:
Purpose: Enhanced external counterpulsation is a non-invasive treatment that increases coronary flow in patients with coronary artery disease (CAD). However, the acute responses of vascular and blood flow characteristics in the conduit arteries during and immediately after enhanced external counterpulsation (EECP) need to be verified. Methods: Forty-two patients with CAD and 21 healthy controls were recruited into this study to receive 45 min-EECP. Both common carotid arteries (CCAs), namely, the left carotid (LC) and right carotid (RC), the right brachial (RB), and right femoral (RF) artery were imaged using a Color Doppler ultrasound. The peak systolic velocity (PSV), end-diastolic velocity (EDV), mean inner diameter (ID), resistance index (RI), and mean flow rate (FR) were measured and calculated before, during, and after the 45 min-EECP treatment. Results: During EECP, in the CCAs, the EDV was significantly decreased, while the RI was markedly increased in the two groups (both P < 0.01). However, immediately after EECP, the RI in the RC was significantly lower than that at the baseline in the patients with CAD (P = 0.039). The FR of the LC was markedly increased during EECP only in the CAD patients (P = 0.004). The PSV of the patients with CAD was also significantly reduced during EECP (P = 0.015) and immediately after EECP (P = 0.005) compared with the baseline. Moreover, the ID of the LC, RB, and RF was significantly higher immediately after EECP than that at the baseline (all P < 0.05) in the patients with CAD. In addition, they were also higher than that in the control groups (all P < 0.05). Furthermore, by the subgroup analysis, there were significant differences in the FR, PSV, and RI between females and males during and immediately after EECP (all P < 0.05). Conclusions: Enhanced external counterpulsation creates different responses of vascular and blood flow characteristics in carotid and peripheral arteries, with more significant effects in both the carotid arteries. Additionally, the beneficial effects in ID, blood flow velocity, RI, and FR after 45 min-EECP were shown only in the patients with CAD. More importantly, acute improvement of EECP in the FR of the brachial artery was showed in males, while the FR and RI of the carotid arteries changed in females.
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