The effects of short course enhanced external counterpulsation combined with loop diuretics on the kidney and cardiovascular system in patients with cardiorenal syndrome

Objective To evaluate the effects of short course enhanced external counterpulsation (EECP) combined with loop Diuretics on the kidney and cardiovascular function in patients with cardiorenal syndrome (CRS). Method A prospective study was conducted on 200 CRS patients who visited the Third Affiliated Hospital of Sun Yat sen University from February 2023 to February 2024. The intervention group was treated with a short course of EECP, using an ECP PSK type oxygen saturation monitoring external counterpulsation device (Chongqing Pushikang Technology Development Co., Ltd.), with an airbag pressure of 0.025 ~ 0.030 MPa, twice a day, 0.5 h per session, which is the current treatment plan. The patients in the intervention group received a short course of EECP for one day (0.5 h per session twice a day). The control group received routine treatment. Treatment principles Maintaining volume, electrolyte, and acid-base stability, using ACEI/ARB drugs reasonably, and continuously purify CRRT blood (only one patient in the intervention group). The primary outcomes were the absolute changes in creatinine and 24-hour intake and output before and after treatment. The secondary outcomes were the estimation of glomerular filtration rate (eGFR), blood urea nitrogen (BUN), cystatin C, urinary protein/creatinine ratio, body weight, NT-proBNP, LVEF, changes in maximum oxygen uptake, expression of endothelin-1, VEGF, inflammatory markers such as IL-10 and NO. Result After a short course of EECP treatment, the median creatinine levels in the intervention group were 107.30 (98.00-137.00) umol/L, while the median creatinine levels in the control group were 195.00 (121.00-245.25) umol/L. There was a statistically significant difference in creatinine levels between the two groups (z = 0.027, 95% confidence interval [CI], 0.024 to 0.030; P < 0.05). After a short course of EECP treatment, the median absolute change in 24-hour intake and output of patients in the intervention group was − 900 (-1500–465) ml, while the median absolute change in 24-hour intake and output of patients in the control group was 570 (362.5-747.5) ml. There was a statistically significant difference in the absolute change in 24-hour intake and output between the two groups (z = 0.017, 95% confidence interval [CI], 0.015 to 0.020; P < 0.05). The intervention group showed significant improvements in blood urea nitrogen (BUN), cystatin C, urinary protein/creatinine ratio, body weight, NT-proBNP, and endothelin-1 compared to the control group (all P < 0.05). The estimated glomerular filtration rate (eGFR), LVEF, maximum oxygen uptake, VEGF, IL-10, NO and other indicators in the intervention group were higher than those in the control group (all P < 0.05). No adverse events such as pulmonary embolism and deep vein thrombosis occurred during the treatment period. Primary outcome of 11 prespecified subgroups showed that women, age > 65 years old, BMI>23 kg/m2, had a history of diabetes, LVEF ≤ 50%, NT-proBNP>900pg/ml, systolic blood pressure>137mmHg, Baseline estimated GFR<60 ml/min/1.73m2, NYHA class III or IV, unable to take ACE inhibitor might have heterogeneous therapeutic effects. Conclusion The use of EECP combined with loop diuretics in CRS patients on the basis of standard treatment can effectively improve renal function and urine output, which can improve left ventricular function and reduce weight. The use of EECP combined with loop diuretics in CRS patients on the basis of standard treatment can improve inflammatory response, which can alleviate clinical symptoms, and reduce the risk of pre renal renal injury. Trial Registration The study protocol was registered in the Chinese Clinical Trial Registry (www.chictr.org.cn). The trial registration number is ChiCTR2400087662. Date of registration is 01/08/2024.