Intravenous thrombolysis in acute ischemic stroke after reversal of warfarin anticoagulation in patients with mechanical heart valve prostheses and an INR > 1.7.
Neumann J, Cernik D, Bilik J • Frontiers in neurology • 2026
In two patients with mechanical aortic valves on warfarin and an INR above 1.7, rapid reversal with four-factor prothrombin complex concentrate followed immediately by standard intravenous thrombolysis led to excellent clinical outcomes without hemorrhagic or thromboembolic complications.
Key Findings
Results
Two patients with mechanical aortic valve prostheses on long-term warfarin presented with acute ischemic stroke and elevated INR, which would normally exclude them from intravenous thrombolysis.
Patient 1 was a 76-year-old man with complete paralysis of the right lower limb, paresis of the right upper limb, and right central facial palsy; admission INR was 3.2.
Patient 2 was a 76-year-old woman with dysarthria, left central facial palsy, and left-sided hemiparesis; admission INR was 1.91.
Both were on warfarin because of mechanical aortic valve replacement.
Results
Neither patient had an arterial occlusion suitable for endovascular therapy, leaving IVT as the only recanalization option.
CT angiography did not demonstrate arterial occlusion suitable for endovascular therapy in either patient.
The authors note the procedure was used 'in the absence of other standard options for recanalization therapy.'
Results
Rapid warfarin reversal with 4F-PCC followed immediately by standard IVT was feasible in both patients.
4F-PCC was administered to achieve rapid normalization of the INR.
Standard IVT was given immediately after INR normalization.
The strategy was applied at admission INRs of 3.2 and 1.91, both above the 1.7 threshold for IVT eligibility.
Results
Both patients showed marked neurological improvement with no hemorrhagic or thromboembolic complications.
No intracranial hemorrhage or other hemorrhagic complications were reported.
No thromboembolic complications (e.g., valve thrombosis) were reported after 4F-PCC administration in these mechanical valve patients.
Conclusions
Both patients achieved complete functional recovery at 3 months.
At the 3-month follow-up, both patients had no residual neurological deficits.
The authors state the outcome was in accordance with previously published cases.
Background
INR is the key determinant of IVT eligibility in warfarin-treated patients with mechanical heart valves, and warfarin remains the only approved anticoagulant for this indication.
Warfarin has largely been replaced by direct oral anticoagulants in routine practice but remains the only approved option for mechanical heart valve prostheses.
The authors present 4F-PCC reversal followed by IVT as a potentially effective strategy for patients with INR >1.7.
What This Means
This report describes two 76-year-old patients with mechanical aortic heart valves who take warfarin, a blood thinner, and who had an ischemic stroke. Because warfarin keeps the blood thin, their INR (a blood-clotting measure) was too high (3.2 and 1.91) for standard clot-dissolving treatment (thrombolysis), which is normally avoided when INR is above 1.7 because of bleeding risk. Neither patient had a blocked artery suitable for mechanical clot removal, so thrombolysis was the main option.
The doctors first gave a drug called four-factor prothrombin complex concentrate to quickly reverse the warfarin effect and bring the INR down, then immediately gave standard thrombolysis. Both patients improved markedly, had no bleeding in the brain or clotting complications (such as clots on the valve), and had fully recovered without lasting deficits at three months.
This research suggests that reversal followed by thrombolysis may be a possible approach for such patients. However, it involves only two cases and has no comparison group, so it cannot show that the approach is safe or effective in general. Larger studies would be needed to confirm it.
Neumann J, Cernik D, Bilik J. (2026). Intravenous thrombolysis in acute ischemic stroke after reversal of warfarin anticoagulation in patients with mechanical heart valve prostheses and an INR > 1.7.. Frontiers in neurology. https://doi.org/10.3389/fneur.2026.1937344