The Society for Cardiovascular Angiography & Interventions updated its SCAI Shock Stages Classification on Monday in an effort to make it easier to use while focusing on the factors relevant to cardiogenic shock treatment. The expert consensus statement, which was published online Monday in the first issue of the Journal of the Society for Cardiovascular Angiography and Interventions and simultaneously in the Journal of the American College of Cardiology. “The new updated definition is easier to use, with tables that have eliminated relatively unnecessary variables and highlighted the more commonly present ones in each shock stage, a more useful cardiac arrest modifier, and a 3-axis model that places the shock stages in context of other variables that need to be considered for the patient in front of you,” said Srihari S. Naidu, MD, chair of the writing group, director of the Cardiac Catheterization Laboratory at Westchester Medical Center, New York, and a SCAI trustee, in a press release announcing the update. The SCAI Shock Stages Classification was first released in 2019. Since then, the updated consensus statement says, validation studies have underscored the correlation of SCAI Shock Stages with mortality across all clinical subgroups, including cardiogenic shock with and without acute coronary syndrome, patients in the cardiac intensive care unit, and patients presenting with out-of-hospital cardiac arrest. The classification’s pyramid has been updated to reflect gradations of severity within each stage and progress or recovery pathways for patients. “Further, we have made it much clearer how patients move up and down the stages if they deteriorate or recover, what these changes do to survival, and how support strategies such as mechanical support devices or vasopressors tie into the various stages,” Naidu said in the press release. The document also includes a table that has been streamlined to include variables most typically seen in cardiogenic shock, along with a revised cardiac arrest modifier definition. The statement notes the heterogeneity of cardiac arrest. The two most relevant factors, the update says, are neurologic status (whether patient is awake or in a coma) and physiologic impact. The document further explains that prolonged arrest “may fundamentally change the patient trajectory if ischemia-reperfusion heralds multi-organ failure.” “At this time, there is no clearly defined CPR duration that would qualify a patient for the ‘A’ modifier and we believe that the ‘A’ modifier should refer to patients with potential anoxic brain injury,” the statement reads. The 2019 classification said the “A” modifier describes “patients who have had a cardiac arrest irrespective of duration (treated with chest compressions or direct cardioversion).” This modifier can be added to a shock stage to clarify the patient’s condition. For example, Stage BA indicates a patient in Stage B (“beginning” cardiogenic shock, with clinical evidence of relative hypotension or tachycardia without hypoperfusion) along with cardiac arrest. “Cardiac arrest remains an important predictor of mortality in patients with cardiogenic shock, but we clarify the risk is in patients with unclear neurogenic status,” SCAI President Timothy D. Henry, MD, vice chair of the writing group, said in the press release. In addition to the American College of Cardiology, the following organizations endorsed the updated consensus statement: American College of Emergency Physicians, American Heart Association, European Society of Cardiology, Association for Acute Cardiovascular Care, Society of Critical Care Medicine, International Society for Heart and Lung Transplantation and Society of Thoracic Surgeons. SCAI noted in its press release that cardiogenic shock, though rare, continues to have high mortality, 50% or higher, despite the development of percutaneous mechanical circulatory support technologies and a national standard of emergent angioplasty and stenting. “SCAI and the endorsing societies anticipate the classification to continue to evolve over time as new data accrue,” the press release concludes, “but believe the updated criteria and associated tables and figures will be able to aid in acute clinical care for these patients, inter-hospital and within hospital communication, and in addition should facilitate clinical trials that will ultimately improve mortality in this high risk population.” Image Credit: Society for Cardiovascular Angiography & Interventions