Impact of a change in vascular access flow volume after percutaneous transluminal angioplasty on cardiac function

Vascular access (VA) is necessary for patients on hemodialysis, and percutaneous transluminal angioplasty (PTA) is a useful treatment for maintaining VA function. PTA immediately increases the VA flow volume, which can affect cardiac function. We investigated the relationship between changes in VA flow volume and cardiac function in patients who underwent PTA. This was a single-center retrospective observational study, including patients who underwent PTA between June 2016 and August 2016. VA flow volume and cardiac function were measured by sonography before and 1 h after PTA. This study included 50 PTA procedures in 50 cases. PTA significantly increased the median VA flow volume from 445 (range, 150-1229) to 725 (350-1268) mL/min. Although the ejection fraction and diameter of the inferior vena cava were unchanged, the cardiac output (CO) and cardiac index increased significantly in most cases. Surprisingly, the CO was decreased in 18% of cases despite the increased VA flow volume. In this atypical group, a high CO before PTA was found to be a significant factor for the decrease in CO by PTA. In most cases, both VA flow volume and CO were increased by PTA, whereas in some cases, the CO was decreased despite an increase in VA flow volume. This atypical phenomenon may be due to the insufficient adaptive response in the peripheral artery and heart and could predict risks for future cardiac events. Therefore, it is important that such patients are carefully followed up on.