Cardiovascular digital health technologies potentially outperform traditional clinical equipment through their noninvasive, on-body, and portable monitoring with mass cardiac data beyond the confines of inpatient settings. However, existing cardiovascular wearables have difficulty with providing medical-grade accuracy with a chronically comfortable and stable patient/consumer device interface for reliable clinical decision-making. Here, we develop an intensive care unit (ICU)-grade breathable cardiac electronic skin system (BreaCARES) for real-time, wireless, continuous, and comfortable cardiac care. BreaCARES enables a novel digital cardiac care platform for health care, outpatient diagnostics, stable intraoperative monitoring during heart surgery, and continuous and comfortable inpatient postoperative cardiac care, exhibiting ICU-grade accuracy while having superior anti-interference stability, portability, and long-term on-skin biocompatibility to the clinically and commercially available cardiac monitors in cardiovascular ICUs.