Ultraearly Repeat Thrombolysis and Spinal Cord Infarction: A Case Report

Dear Editor,

Spinal cord infarction is an uncommon cause of acute ischemic strokes (AIS), accounting for around 1% to 2% of all strokes[1], due to extensive collateral supply. At present, there are no guidelines for the treatment of spinal cord infarction with intravenous thrombolysis (IVT). In addition, the role of repeat IVT in cases of recurrent strokes within 3 months is not established, and treatment is based on previous case reports or meta-analyses. In this article, we discuss a patient who presented with two episodes of strokes due to a single arterial supply to the spinal cord and medulla (spinal cord infarction and medial medullary syndrome) and was treated with repeat IVT within 3 days after the first stroke.

A 54-year-old male with hypertension and diabetes mellitus on treatment presented to the emergency room with acute-onset weakness and reduced sensation in both lower limbs. His pulse rate was 86 beats per min, regular, and blood pressure (BP) was 170/100 mmHg. On neurological examination, he was conscious and alert; visual acuity, extra-ocular movements, cranial nerves, and upper limbs were normal. Power was medical research council (MRC) grade 3/5 in both lower limbs. Temperature and pain sensation were impaired below the knees, including perianal sensation, while joint position and vibration sense were intact. Deep tendon reflexes were inelicitable in the lower limbs, normal in the upper limbs, with a bilateral Babinski reflex. A clinical diagnosis of anterior cord syndrome secondary to anterior spinal artery occlusion was considered. Magnetic resonance imaging (MRI) brain revealed patchy areas of diffusion restriction in the anterior spinal artery territory, extending from D4 to D10, with normal brain parenchyma and vasculature [Figure 1]. The patient was thrombolyzed with intravenous tenecteplase 18 mg (0.25 mg/kg) at 5 h after the onset of symptoms. He improved over the next 24 h. Blood laboratory investigations were normal, except for serum homocysteine, which was markedly elevated (60 mg/dl). The echocardiogram was normal. He was started on a single antiplatelet agent after 24 h.

Figure 1.

(First event): (a) MRI spine showing diffusion restriction and corresponding ADC drop in the thoracic spine from D9 to D10. (b) No abnormality in brain parenchyma. ADC: Apparent diffusion coefficient, MRI: Magnetic resonance imaging

On day 3 of the hospital stay, he reported new-onset weakness of the right upper and lower limbs (power 2/5 in the upper limb and 3/5 in the lower limb) and mild dysarthria. MRI of the brain revealed diffusion restriction in the left medial medulla, and angiogram showed mild focal narrowing of the right vertebral artery near the vertebrobasilar junction [Figure 2]. The diffusion restriction in the dorsal cord had resolved completely. There was a treatment dilemma at this point, as the patient had been thrombolyzed 3 days earlier. After careful review of the published literature and discussion of risks and benefits with the family, the decision to proceed with repeat IVT was made. The patient was thrombolyzed again with a lower dose of tenecteplase, 14 mg (0.20 mg/kg), at 4.5 h from the onset of weakness. Power in the right upper limb improved to MRC 3/5, and lower limb power improved to MRC grade 4/5. DSA revealed moderately severe stenosis in the V4 segment of the right vertebral artery with a small luminal thrombus [Figure 3]. The left vertebral artery showed moderately severe stenosis at its origin. The anterior spinal artery was not well visualized. The diseased vertebral artery was considered the source of emboli strokes in both the spinal cord and medulla. The patient was administered an injection of low molecular weight heparin (LMWH) for 5 days in view of the luminal thrombus. He was discharged after 1 week on dual antiplatelets [National Institutes of Health Stroke Scale score (NIHSS): 3]. At 1-month follow-up, the patient had recovered completely (modified Rankin score: 0).

Figure 2.

(a) (second event): Diffusion restriction with corresponding ADC drop in the medial medulla and no bleed on GRE. (b) MRI brain and neck angiogram showing no obvious abnormality. (c) Reversal of DWI changes in the spinal cord. ADC: Apparent diffusion coefficient, DWI: Diffusion weighted image, GRE: Gradient echo, MRI: Magnetic resonance imaging

Figure 3.

(a) DSA showing moderate stenosis at origin of left vertebral artery. (b) right vertebral shoot showing moderate stenosis in V4 segment and poor visualization of anterior spinal artery. DSA: Digital substraction angiography

Stroke is a leading cause of morbidity and mortality. The effectiveness of IVT and mechanical thrombectomy has been studied extensively for anterior circulation stroke and is evolving in posterior circulation stroke. However, the treatment of spinal cord ischemia has mostly been limited to medical management and rehabilitation, given the rarity of this type of stroke and the absence of current guidelines.[2,3] Our case is unique in three noteworthy aspects. First, thrombolysis of spinal cord ischemia at 5 h from the onset of stroke. Second, repeat thrombolysis for recurrent stroke within 3 days of the first stroke. Third, strokes occurring in distinct anatomical regions that shared a single arterial supply. There have been individual case reports regarding thrombolysis in spinal cord infarction. In a recent study, Chandak et al.[4] reviewed 19 such cases and found that IVT is reasonable in spinal cord infarction. There are no documented data on the incidence of spinal cord hemorrhage post-IVT, given the rarity of the condition, as described in meta-analysis of case reports. However, spinal epidural hematoma after IVT for AIS has been reported.[5] The second stroke, occurring 3 days later, led to a treatment dilemma. Acute ischemic stroke within 3 months is a contraindication for IVT due to a higher risk of intracranial hemorrhage (ICH). Despite this guideline-based contraindication, there is growing literature supporting repeat thrombolysis in select cases. A recent analysis by Wen et al.[6] showed that repeat IVT can be considered in patients who had a good outcome with previous thrombolysis and a low NIHSS score at the time of the recurrent stroke. High baseline NIHSS score, short interval between IVT, and cardiogenic embolism can increase the risk of symptomatic ICH. Kahles et al.[7] noted that small-volume infarcts and improvement after the first stroke with IVT can be considered for repeat IVT. Although the interval between IVT sessions was short in our patient, he had an excellent outcome after the first thrombolysis and a low NIHSS score during the second event. A multi-centre study by Etgen et al. analyzed the effect of ultra-early repeat systemic thrombolysis (within 10 days) in recurrent stroke. They found that the median time between the two thrombolyses was 3.5 days, with favorable outcomes and ICH rates comparable to previous studies.[8] There is no strong recommendation for a low dose in repeat IVT, but meta-analyses have described the efficacy and safety of low-dose IVT.[9,10,11] This is one of the few cases in which the patient was treated twice with IVT within 3 days.[12] It is important to highlight that the strokes were likely the result of unique vascular anatomy. Many variations in the formation of spinal arteries have been described [Figure 4].[13] An anterior spinal artery that courses down from the medulla adjacent to the pyramids can result in medullary infarction and anterior cord syndrome. Our patient had a type 2 variation, which likely explains the concurrent vulnerability of both the medulla and anterior spinal cord to ischemia.

Figure 4.

The origin and variations of anterior spinal

This case emphasizes the importance of maintaining a high degree of suspicion for spinal cord infarction in patients presenting with nontraumatic acute paraplegia and of individualized decision-making in complex stroke presentations. While spinal cord infarction and repeat thrombolysis remain areas lacking established guidelines, emerging evidence and clinical judgment can guide management. Timely intervention, even in challenging scenarios, can significantly improve patient outcomes.

Declaration of patient consent

The authors certify that they have obtained all appropriate patient consent forms. In the form, the patient has given his consent for his images and other clinical information to be reported in the journal. The patients understand that their names and initials will not be published and that due efforts will be made to conceal their identity, but anonymity cannot be guaranteed.

Conflicts of interest

There are no conflicts of interest.

Funding Statement

Nil.