Linear relationship seen with worsening aortic valve stenosis
The higher the plasma levels of certain lipoproteins and their components, the faster the progression of calcific aortic valve stenosis among people with mild-to-moderate jets -- with no threshold found for this relationship, a study showed.
Valve stenosis was more likely to progress rapidly (Vpeak going up by at least 0.20 m/s per year) with increasing baseline levels of:
- Lipoprotein(a): OR 1.10 per 10 mg/dL (95% CI 1.03-1.19)
- Oxoidized phospholipids on apolipoprotein B (OxPL-apoB): OR 1.06 per 1 nM (95% CI 1.01-1.12)
- Oxoidized phospholipids on apolipoprotein(a) (OxPL-apo[a]): OR 1.16 per 10 nM (95% CI 1.05-1.27)
These findings stayed robust after multivariable adjustment. Notably, aortic jet velocity progressed especially fast in patients 57 years or younger with these same increases in the markers, according to Philippe Pibarot, DVM, PhD, of Institut Universitaire de Cardiologie et de Pneumologie de Québec in Québec City, and colleagues reporting online in JAMA Cardiology
"This study demonstrates that the association of Lp(a) [lipoprotein(a)] levels and its content in OxPL with faster CAVS [calcific aortic valve stenosis] progression is linear, reinforcing the concept that Lp(a) levels should be measured in patients with mild to moderate CAVS to enhance management and risk stratification," they said.
But the idea of a certain threshold value of these lipoproteins and components for worsening valve stenosis was not supported by the data, the authors suggested.
Pibarot's group performed a secondary analysis of ASTRONOMER, a Canadian trial on statin therapy conducted in the early 2000s. It included 220 patients with preexisting mild to moderate calcific aortic valve stenosis (peak aortic jet velocity 2.5-4.0 m/s).
Among those with baseline lipoprotein(a) under 60 mg/dL, jets strengthened by 0.17 m/s every year for every incremental increase in lipoprotein(a), OxPL-apoB, or OxPL-apo(a) as noted above.
The group starting with lipoprotein(a) in the 60-100 mg/dL range had Vpeak increase by approximately 0.20-0.26 m/s with more of these markers in plasma. Patients with lipoprotein(a) levels over 100 mg/dL progressed by around 0.30-0.35 m/s per year.
With such fast progression, individuals with high lipoprotein(a) may turn out to be a group that would need more frequent surveillance by Doppler echocardiography, Pibarot and colleagues suggested.
"These data add to the increasing database that Lp(a) is not only associated with prevalent aortic valve calcification, but also with rapid progression of preexisting CAVS," the authors said, noting that the only option for this condition is aortic valve replacement.
That the cohort comprised 60.0% men who were on average 58 years old limits the generalizability of the findings to older patients and people with more severe aortic stenosis, the investigators acknowledged.
Pibarot disclosed no conflicts of interest.
A co-author reported being a co-inventor and receiving royalties from patents owned by University of California San Diego (UCSD), being a co-founder of Oxitope, consulting to Boston Heart Diagnostics, and holding a dual appointment at UCSD and Ionis Pharmaceuticals.
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Source Reference: Capoulade R, et al “Association of mild to moderate aortic valve stenosis progression with higher lipoprotein(a) and oxidized phospholipid levels: Secondary analysis of a randomized clinical trial” JAMA Cardiol 2018; DOI: 10.1001/jamacardio.2018.3798.
Read the original article on Medpage Today: Lipoprotein Levels May Inform Timing of Aortic Valve Replacement