Patients with moderate aortic stenosis have a potentially increased risk of death and cardiovascular mortality regardless of age, sex and left ventricular ejection fraction, an Australian and US study has found.
Researchers say the evidence now suggests the condition – which is often asymptomatic – could kill up to 50,000 Australians in the next five years without treatment.
Funded with an unconditional grant from artificial valve manufacturer Edwards Lifesciences, the multicentre study included cohorts of 30,865 US and 217,599 Australian patients with equivalent echocardiographic and aortic valve profiling over the same period (2003–2017).
During a median 5.2 year follow-up, the US patients with moderate AS had a 1.66 times higher risk of death compared to those without the condition.
The Australian cohort had a shorter median follow-up at 4.4 years, but again the mortality risk was higher in patients with moderate AS compared to those without (OR 1.37).
Moderate AS was classified using standard echocardiographic criteria of 20.0–39.9 mmHg / 3.0–3.9 m/s and aortic valve area ≥1.0 cm2.
Nevertheless, on a fully adjusted basis, the associated risk of mortality in patients meeting those criteria was like that of severe AS, the researchers wrote in PLOS ONE.
The relationship persisted when accounting for potential confounders including the effective valve orifice areas, history of hypertension, diabetes, CAD and/or subsequent coronary revascularisation, chronic kidney disease, the syndrome HF and more than 30 other clinical, laboratory, and medication variables that would influence an individual’s clinical trajectory and prognosis.
“Overall, these data indicate that moderate AS is not a benign entity; thereby challenging the current ‘watchful wait’ approach currently advocated for many patients,” they wrote.
” Hence, these data suggest the need to develop specific strategies to detect and treat individuals with moderate AS,” they concluded.
Study co-author Professor David Playford told the ABC previous research had found aortic valve replacement was “associated with markedly improved survival”.
That study estimated close to 100,000 Australians aged ≥ 55 years were currently living with AS.
“Accordingly, in the next five years, more than half of these individuals will die without having undergone an AVR procedure – their risk of dying being two-fold higher on an adjusted basis than their counterparts without severe AS,” it said.
“From an individual to societal perspective, it seems clear that due to Australia’s progressively ageing population, a clear strategy to detect and then optimally manage an increasing burden of AS is urgently required.”