#1259 Relationship between renal dysfunction, non-obstructive ACS and in-hospital prognosis: findings from the CCC-ACS project
Authors: Ye Nan , Wang Guoqin , Bian Weijing , Zhao Dong , Liu Jing , Hao Yongchen , Liu Jun , Yang Na , Cheng Hong 
Published: May 2024

Abstract

Background and Aims
Acute coronary syndrome (ACS) is an acute and critical condition of coronary heart disease (CHD) with high mortality and poor prognosis. The prevalence of non-obstructive ACS is about 5% ∼ 15%. Among patients with non-obstructive ACS, which patients are more prone to poor prognosis is a concern. Chronic kidney disease (CKD) is an important risk factor for cardiovascular disease, and due to its special pathophysiological mechanism, non-obstructive ACS may not be uncommon in CKD patients. Therefore, the aim of this study was to investigate the relationship between renal function, the occurrence and prognosis of non-obstructive ACS.

Method
Improving Care for Cardiovascular Disease in China - Acute Coronary Syndrome (CCC-ACS), a hospital-based medical quality improvement project, is a hospital-based medical quality improvement project to improve the compliance of ACS guidelines in China and improve the prognosis of patients. It was jointly sponsored by the American Heart Association (AHA) and the Chinese Society of Cardiology (CSC) in 2014, with 240 hospitals participating, representing different levels of ACS management in Chinese hospitals. We analyzed patients who underwent coronary angiography from November 2014 to July 2019 in CCC-ACS. Patients were divided into eGFR &lt;60 ml/min·1.73 m² and eGFR≥60 ml/min·1.73 m² groups according to estimated glomerular filtration rate (eGFR) calculated by the EPI formula. According to the results of coronary angiography, the patients were divided into obstructive ACS group and non-obstructive ACS group (obstructive ACS group was defined as at least one coronary artery stenosis ≥ 50%; the others were non-obstructive ACS group). Outcome was defined as in-hospital all-cause mortality and in-hospital MACEs.

Results
A total of 77 586 patients were included, including 2 292 patients (3.0%) with non-obstructive ACS and 75 294 patients (97.0%) with obstructive ACS. After adjusting for confounding factors using a multivariate logistic regression model, patients with eGFR&lt;60 ml/min·1.73 m² had an approximately 20% increased risk of non-obstructive ACS compared with patients with eGFR≥60 ml/min·1.73 m². The comparison of in-hospital outcomes between the patients with non-obstructive ACS and obstructive ACS is shown in Fig. 1. In-hospital outcomes showed that although the obstructive ACS group had a worse in-hospital prognosis than the non-obstructive ACS group, and the eGFR&lt;60 ml/min·1.73 m² group had a worse in-hospital prognosis than the eGFR≥60 ml/min·1.73 m² group, further grouping of patients showed that the non-obstructive ACS group with eGFR&lt;60 ml/min·1.73 m² had a worse prognosis than the obstructive ACS group with eGFR≥60 ml/min·1.73 m². Confounding factors adjusted for non-obstructive ACS showed that lower eGFR was associated with a higher risk of in-hospital MACEs. After analyzing the in-hospital medication and discharge medication of patients, it was found that the standardized cardiovascular drug therapy was inadequate in patients with non-obstructive ACS.

Conclusion
Patients with non-obstructive ACS have worse renal function than patients with obstructive ACS, and the proportion of patients with eGFR&lt;60 ml/min·1.73 m² is higher. In patients with non-obstructive ACS, the risk of in-hospital MACEs significantly increased as eGFR decreased. This suggests that we may consider giving standardized cardiovascular drug therapy to patients with non-obstructive ACS, especially those with non-obstructive ACS combined with abnormal renal function, in order to improve the prognosis of patients. This needs to be confirmed by more randomized controlled trial results.