Aortic Stenosis: Are We Missing Acute Valvular Syndromes?

Gabriel Steg, MD, explores whether acute valvular syndromes are being overlooked in aortic stenosis. This transcript has been edited for clarity. Hello. Today I’d like to talk about a change in how we think about aortic valve stenosis. Traditionally, aortic stenosis has been seen as a slow, progressive, and insidious disease. It has usually been understood to progress through a prolonged asymptomatic phase, followed by mild, subtle symptoms that gradually worsen over time.But that is not always what we see in practice. We have all seen patients whose disease course is much more abrupt and discontinuous, with no intermediate phase. Recent data, notably from the Early TAVR trial and from large observational series, show that a significant proportion of patients — up to 40% — may present with severe acute symptoms from the outset, without first going through a paucisymptomatic phase.These severe acute symptoms can appear quite suddenly. Acute pulmonary edema, cardiogenic shock, syncope, or cardiac arrest may be the first manifestations, before valve replacement becomes necessary. This is even more striking in cohorts of patients who undergo valve replacement, where the majority — up to 70% — had advanced symptoms before the procedure.This is not just an academic distinction. Patients who present with acute decompensation have a much worse prognosis after valve replacement, with rates of death and hospitalization for heart failure that are three to four times higher than in those who underwent valve replacement while still asymptomatic.These findings led Philippe Généreux, Brian Lindman, and Philippe Pibarot to propose, in an editorial in Circulation, a new classification of what they call valvular syndromes. The first stage is the stable valvular syndrome. These are patients who have no symptoms and no signs. The second stage is progressive valvular syndrome, which includes patients with mild or progressive symptoms such as shortness of breath on exertion, fatigue, dizziness, or even elevated cardiac markers such as BNP or NT-proBNP.The third stage is what they call acute valvular syndrome. These are patients with severe and acute symptoms, which may include acute pulmonary edema, syncope, supraventricular arrhythmia, cardiac arrest, cardiogenic shock, or even — and perhaps we can discuss this — a marked elevation in cardiac biomarkers.If the condition remains asymptomatic, then it may not yet qualify as acute valvular syndrome. In any case, what is clear is that these three categories of patients have radically different prognoses. Stable valvular syndromes have a prognosis that is not very different from that of patients who are free of symptoms and disease.Patients with progressive syndrome have a moderately increased risk. However, acute valvular syndromes have a significantly worse outcome than the other groups, with mortality more than double and hospitalizations more than triple. So, why is this proposed new classification important?First, because it captures a clinical reality that we all observe. We have all seen patients who suddenly decompensate, and the idea that careful monitoring can prevent decompensation is not supported by clinical observation. This classification therefore allows for better patient stratification and clearer identification of those who will require urgent treatment.It is also a standardization tool for research that will allow us to better describe the populations participating in clinical trials and to serve as a baseline for studies that monitor the natural history of the disease or evaluate future treatments — particularly medical treatments for aortic stenosis — because we all know that, in the future, there will likely be treatments that can slow the progression of aortic valve disease.Beyond the trigger mechanism, there are also the underlying mechanisms. Here again, by analogy with what is done, for example, in myocardial infarction, the authors distinguish what they call type 1 — valvular syndromes that are purely related to valvular disease — and type 2, which are triggered by concomitant factors such as myocardial ischemia, supraventricular arrhythmia, or cardiac amyloidosis.Once again, I think this is a classification that forces us to think a little differently and will allow us to better describe and classify the clinical presentation of our patients. And finally, having moved from acute coronary syndrome to chronic coronary syndrome, we will likely move from chronic valvular syndrome to acute valvular syndrome to better track our performance, and to better assess and better classify our patients.This video was translated from Medscape’s French edition.