Effects of Enhanced External Counterpulsation With Different Sequential Levels on Lower Extremity Hemodynamics

Research focus and theme evolution on enhanced external counterpulsation: A bibliometric analysis

Aims

The study delved into the identification of key research areas and evolving trends within the domain of Enhanced External Counterpulsation, aiming to gain comprehensive insights into the subject matter.

Methods

Utilizing the sophisticated search parameter of 'topic' (TS) on the Web of Science (WoS) database, the necessary information was retrieved. This research employed an array of tools for effective data extraction, analysis, and visualization, which included Microsoft Excel for tabular management, HistCite Pro for citation analysis, GunnMap for geographical mapping, BibExcel for bibliometric assessments, and VOSviewer for network visualization purposes.

Results

From its establishment up until March 31, 2024 a total of 535 entries were recorded in the WoS database, with 491 of these relevant to the specified subject matter. The USA was the most prolific country, and China ranked second. Sun Yat Sen University was the most productive institution, which was from China. And 80 % of the top 10 institutions were from the USA. A keyword co-occurrence analysis was conducted, revealing four distinct research foci. And they were the application of EECP in cardiovascular disease, the main indications of EECP, the mechanism of EECP and the therapeutic effect of EECP, respectively. Researchers paid the most attention to the application of EECP on the cardiac cardiovascular system. Professor Lawson WE, Hui JCK and Kennard ED were the top three prolific authors. Lawson WE, Henry TD, Braith RW and Zheng ZS were identified as the core authors in the author co-citation network analysis.

Conclusion

A comprehensive analysis was conducted on the literature surrounding improved enhanced external counterpulsation in this investigation, which can help researchers understand the theme trend better and grasp the research gap, to carry out further research and promote the progress of the topic.

Effect of enhanced external counterpulsation versus individual shear rate therapy on the peripheral artery functions

In this study, we aimed to assess the effects of enhanced external counterpulsation (EECP) and individual shear rate therapy (ISRT) on peripheral artery function in patients with lower extremity atherosclerotic disease (LEAD). We randomly assigned 45 LEAD patients to receive 35 sessions of 45 min of EECP (n = 15), ISRT (n = 15), or sham-control (n = 15). Flow-mediated dilation in the brachial artery (brachial-FMD); 6-min walk distance; blood flow in the popliteal, posterior tibial, anterior tibial, and dorsalis pedis arteries; and plasma levels were measured before and after the 7 weeks treatment. 36-item Short Form Health Survey [SF-36] was analyzed before, after 7 weeks, and 3-month follow-ups. EECP treatment significantly improved brachial-FMD and quality of life, increased walking distance, and increased blood flow and the diameters of the popliteal artery and posterior tibial artery (all P < 0.01). Conversely, ISRT markedly increased blood flow in the anterior tibial artery (P < 0.05). EECP and ISRT decreased the endothelin-1 and asymmetrical dimethylarginine levels in patients with LEAD (both P < 0.01). Additionally, sVCAM-1 was significantly reduced after EECP intervention (P = 0.004). Our findings demonstrate that EECP and ISRT have beneficial effects on walking distance, quality of life, flow-mediated dilation, endothelial-derived vasoactive agents, and inflammatory and oxidative stress in LEAD patients.Date of registration: 2021-06-21. Trial registration: ChiCTR2100048086.

Evaluation of enhanced external counterpulsation for diabetic foot based on a patient-specific 0D-1D cardiovascular system model

BACKGROUND AND OBJECTIVE

Diabetic foot (DF) complications often lead to severe vascular issues. This study investigated the effectiveness of enhanced external counterpulsation (EECP) and its derived innovative compression strategies in addressing poor perfusion in DF. Although developing non-invasive and efficient treatment methods for DF is critical, the hemodynamic alterations during EECP remain underexplored despite promising outcomes in microcirculation. This research sought to address this gap by developing a patient-specific 0D-1D model based on clinical ultrasound data to identify potentially superior compression strategies that could substantially enhance blood flow in patients with DF complications.

METHODS

Data were gathered from 10 patients with DF utilizing ultrasound for blood flow rate and computed tomography angiography (CTA) to identify lower limb conditions. Clinical measurements during standard EECP, with varying cuff pressures, facilitated the creation of a patient-specific 0D-1D model through a two-step parameter estimation process. The accuracy of this model was verified via comparison with the clinical measurements. Four compression strategies were proposed and rigorously evaluated using this model: EECP-Simp-I (removing hip cuffs), EECP-Simp-II (further removing the cuffs around the lower leg), EECP-Impr-I (removing all cuffs around the affected side), and EECP-Impr-II (building a loop circulation from the healthy side to the affected side).

RESULTS

The predicted results under the rest and standard EECP states were generally closely aligned with clinical measurements. The patient-specific 0D-1D model demonstrated that EECP-Simp-I and EECP-Impr-I contributed similar enhancement to perfusion in the dorsal artery (DA) and were comparable to standard EECP, while EECP-Simp-II had the least effect and EECP-Impr-II displayed the most significant enhancement. Pressure at the aortic root (AO) remained consistent across strategies.

CONCLUSIONS

EECP-Simp-I is recommended for patients with DF, emphasizing device simplification. However, EECP-Simp-II is discouraged as it significantly diminished blood perfusion in this study, except in cases of limb fragility. EECP-Impr-II showed superior enhancement of blood perfusion in DA to all other strategies but required a more complex EECP device. Despite increased AO pressure in all the proposed compression strategies, safety could be guaranteed as the pressue remained within a safe range.

A numerical study on the siphonic effect of enhanced external counterpulsation at lower extremities with a coupled 0D-1D closed-loop personalized hemodynamics model

Enhanced external counterpulsation (EECP) is a treatment and rehabilitation approach for ischemic diseases, including coronary artery disease. Its therapeutic benefits are primarily attributed to the improved blood circulation achieved through sequential mechanical compression of the lower extremities. However, despite the crucial role that hemodynamic effects in the lower extremity arteries play in determining the effectiveness of EECP treatment, most studies have focused on the diastole phase and ignored the systolic phase. In the present study, a novel siphon model (SM) was developed to investigate the interdependence of several hemodynamic parameters, including pulse wave velocity, femoral flow rate, the operation pressure of cuffs, and the mean blood flow changes in the femoral artery throughout EECP therapy. To verify the accuracy of the SM, we coupled the predicted afterload in the lower extremity arteries during deflation using SM with the 0D-1D patient-specific model. Finally, the simulation results were compared with clinical measurements obtained during EECP therapy to verify the applicability and accuracy of the SM, as well as the coupling method. The precision and reliability of the previously developed personalized approach were further affirmed in this study. The average waveform similarity coefficient between the simulation results and the clinical measurements during the rest state exceeded 90%. This work has the potential to enhance our understanding of the hemodynamic mechanisms involved in EECP treatment and provide valuable insights for clinical decision-making.