LAS VEGAS – The Society for Cardiovascular Angiography & Interventions released on May 19 the first-ever classification scheme for cardiogenic shock, dividing the condition into five severity levels.
The expert consensus panel that devised the new definition and classification model hopes it will spearhead a reset of research into the management of cardiogenic shock so that clinicians can assess interventions and introduce them into practice in a more precise, reproducible, and systematic way,, said while presenting the proposal at the society’s annual scientific sessions.
The writing panel’s hope is that the new definition will “drive earlier recognition of shock and at a more precise stage to guide appropriate and timely escalation of care” and to “better define prospectively the value of mechanical circulatory support, extracorporeal membrane oxygenation, and other therapies,” said Dr. Naidu, chair of the writing group, as well as professor of medicine at New York Medical College and director of the cardiac catheterization laboratory at Westchester Medical Center, both in Valhalla, N.Y.
At the core of the classification scheme are the definitions for five strata of disease, which start at stage A, the “at-risk” patients before shock onset, and progress through stage B, “beginning”; stage C, “classic”; stage D, “deteriorating”; and stage E, “extremis,” which defines a patient with circulatory collapse (Catheter Cardiovasc Interv. 2019 May 19;). Another key element of the classification model is the cardiac arrest “modifier,” designated by a subscripted letter A, which identifies patients who have had a cardiac arrest, regardless of duration. So a patient could be a stage BA, which identifies a patient with clinical evidence of relative hypotension or tachycardia without hypoperfusion and with a history of cardiac arrest.
The statement also itemizes several biomarkers and hemodynamic measurements that need regular, serial monitoring, such as blood lactate and right arterial pressure. Although the document leaves specific, defining values for some of these measures vaguely defined – the intent is that future research will fill in these gaps – the overall message is that clinicians caring for cardiogenic shock patients “need to be aggressive and look for these things,” Dr. Naidu said in a video interview.
“Until we agree on a definition of cardiogenic shock, we can’t go anywhere,” commented, professor of medicine at and director of the Regional Heart Center of the University of Washington in Seattle. “There are a lot of conflicting data out there, and until we have a shared definition, we can’t advance our practice. We need to start looking at shock patients in a more precise way.”
“Without a clear definition of cardiogenic shock we will never improve patient outcomes. Every shock trial must define shock. If investigators just say ‘patients were in shock,’ I don’t know what that means,” noted, director of the Interventional Research Laboratories at Tufts Medical Center in Boston and a member of the writing panel.
Dr. Naidu and others on the panel highlighted the need to now validate the classification scheme’s ability to consistently categorize patients and predict their disease trajectories. They have begun the validation process with a 10,000-patient database of “all-comers” with cardiogenic shock maintained by the Mayo Clinic. Full results from this analysis will be out soon, but Dr. Naidu revealed in passing that it successfully provided validation of the proposed scheme.
The new definition received endorsements from the American College of Cardiology, the American Heart Association, the Society of Critical Care Medicine, and the Society of Thoracic Surgeons.
Dr. Naidu had no disclosures.