Time between stroke and SAVR influences post-SAVR ischaemic stroke, MACE risk
Undergoing surgical aortic valve replacement (SAVR) within 3 months of a stroke significantly raised the risk of a subsequent ischaemic stroke and major adverse cardiovascular events (MACE) among patients with aortic valve stenosis, according to a study from Denmark.
“Patients with recent stroke [within 3 months] had markedly heightened risk of recurrent stroke during surgery, and the risk declined with time,” said the researchers.
“[D]ata suggest that postponement of SAVR for at least 3 to 4 months after a stroke, if possible, may reduce the risk of recurrent stroke during surgery,” they said, highlighting the need for a randomized clinical trial to establish this finding.
Researchers used data from five Danish registries to identify 14,030 individuals aged >18 years with aortic valve stenosis who underwent first SAVR between 1996 and 2014. Of these, 616 (mean age 72.0 years, 30.8 percent female) had a stroke and 13,414 (mean age 69.8 years, 36.1 percent female) did not have a stroke prior to undergoing SAVR.
Pre-operative atrial fibrillation (AF), peripheral artery disease, ischaemic heart disease, carotid stenosis, and use of antithrombotics, renin-angiotensin system inhibitors, and statins were more common among patients with prior stroke than those without stroke.
At 30 days post-surgery, patients who had a stroke <3 months prior to undergoing SAVR had an elevated risk of an ischaemic stroke compared with patients who did not have a stroke pre-SAVR (18.4 percent vs 1.2 percent, odds ratio [OR], 14.69, 95 percent confidence interval [CI], 9.69–22.27). [JAMA Cardiol 2018;doi:10.1001/jamacardio.2018.0899]
Having a stroke <3 months before SAVR also raised the risk of MACE (composite of nonfatal myocardial infarction, nonfatal ischaemic stroke, or cardiovascular-related death) at 30 days compared with no stroke (23.3 percent vs 5.7 percent, OR, 4.57, 95 percent CI, 3.24–6.44). However, there was no increased risk of all-cause mortality at 30 days between patients who had a stroke <3 months prior to surgery and those with no stroke (6.8 percent vs 3.6 percent, OR, 1.45, 95 percent CI, 0.83–2.54).
Compared with those who had no prior stroke, the risk for ischaemic stroke at 30 days was also elevated among those who had a stroke 3 to <12 months (OR, 3.96) and ≥12 months before SAVR (OR, 2.29) though it was lower than that of patients who had a stroke <3 months pre-SAVR.
The 30-day risk of MACE was further elevated in patients with a history of stroke who also had AF (OR, 5.26 vs 1.81 [no AF]; p<0.001) or were aged <75 years (OR, 3.19 vs 2.22 [age >75 years]; p=0.03), regardless of time between initial stroke and SAVR.
Nonetheless, the researchers suggested that AF may not be behind the increased post-SAVR stroke risk in patients with recent stroke as the risk “was apparent both in patients with and without AF”.
While previous research has indicated that individuals with a prior stroke are at an elevated risk of stroke following cardiac surgery, the impact of timing of SAVR after a stroke has not been sufficiently addressed, said Assistant Professor Michael Mullen and Associate Professor Steven Messe from the University of Pennsylvania, Philadelphia, Pennsylvania, US, in an editorial. [JAMA Cardiol 2018; doi:10.1001/jamacardio.2018.0898]
They acknowledged that potentially more thorough monitoring of patients with a history of stroke may have influenced the results, as was the possibility of patients with a prior stroke being “sicker or at higher risk than those who were able to wait” for surgery.
The researchers also pointed out that the observational nature of the study precluded any firm conclusions being made on the association between timing of SAVR and stroke and MACE risk, and that the predominantly Caucasian population prevented the extension of these findings to other ethnicities.
“Nonetheless … although this is an area that requires additional study, for now, it seems reasonable to avoid aortic valve surgery or any surgery within the first 3 months after a stroke unless the procedure is urgent or emergent and waiting would be harmful,” said Mullen and Messe.