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Acute fluctuating neurological deficits after pulmonary vein isolation: unmasking a rare complication due to spontaneous spinal subdural bleeding: a case report

Abstract Background Pulmonary vein isolation (PVI) is becoming the therapy of choice for symptomatic paroxysmal drug-refractory atrial fibrillation (AF). The most frequently reported complications are vascular complications (1.4%). Bleeding complications of the central nervous system have rarely been described. We report a case of spontaneous spinal bleed after PVI. Case summary A 68-year-old woman with a 2-year history of highly symptomatic paroxysmal AF (EHRA 3) was referred for a PVI redo procedure. A high-density mapping showed pulmonary vein reconnection of all pulmonary veins successfully isolated by radiofrequency ablation. During the entire procedure, the patient had sinus rhythm with an ACT around 300 s. No intraprocedural and peri-procedural complications occurred. Four hours after haemostasis, the anticoagulation clotting time (ACT) was 110 s and rivaroxaban (20 mg) was reinitiated. In the following hours, the patient developed fluctuating neurological lower limb symptoms. A lumbar magnetic resonance imaging showed a subdural spinal haematic collection with an associated epidural component from L3 to S2 exerting compression over the dural sheath. A conservative treatment approach was adopted with progressive recovery of sensorial and motor deficits. After 5 months, the patient still presented residual lower limb motor deficits necessitating the support of a walking stick. Discussion We describe the first case of a spontaneous spinal bleeding following PVI. Given the gradual diffusion of PVI to treat AF in more clinically complex patients with a larger range of comorbidities, particular consideration should be given to seek predisposing bleeding factors in order to assess the risk for neurological complications.


Introduction
Pulmonary vein isolation (PVI) is becoming the therapy of choice for symptomatic paroxysmal drug-refractory atrial fibrillation (AF). The most frequently reported complications are vascular complications (1.4%) in a setting of overall low complication rate (<2.9%). 3 Bleeding complications of the central nervous system (CNS) have rarely been described. We report a case of spontaneous spinal bleeding after PVI not reported in the literature so far.

Case presentation
A 68-year-old woman with a 2-year history of highly symptomatic drug-refractory paroxysmal AF (EHRA 3), previously treated with a previous PVI procedure, was referred to our division for a PVI redo procedure. The patient (height 160 cm, weight 69 kg) presented a history of two-vessel coronary artery disease treated with percutaneous revascularization, a CHA 2 DS 2 -VASc score of 4, and HAS-BLED score of 2. She had a history of hypertension, hypothyroidism, and a congenital ostium secundum atrial septal defect with a left-right spontaneous shunt. The patient presented also moderate kyphoscoliosis of the vertebral column, most prominent at the lumbar level. She was treated with rivaroxaban 20 mg/day, aspirin, sotalol, thyroxin, furosemide/spironolactone medication, and pantoprazole. The preprocedural blood values, including routine coagulation indices were all normal.
The anticoagulation therapy was interrupted 36 h before the procedure and a transoesophageal echocardiogram performed on the same day of the procedure excluded left atrial appendage thrombi. The procedure was performed under general anaesthesia and vascular access was obtained through the right femoral vein. High-density mapping was performed during sinus rhythm and showed pulmonary vein reconnection of all pulmonary veins. A radiofrequency ablation catheter (Thermocool Smarttouch, Inc., Irvine, CA, USA) was performed; it showed a reconnection of three pulmonary veins. A mapping procedure obtained 20 min after the last ablation point showed a persistent deconnection of all pulmonary veins. Atrial programmed stimulation as well as repeated high-rate pacing bursts did not induce AF. During the entire procedure, the patient had a sinus rhythm, remained stable with vital signs within range of normality; ACT was stable around 300 s with a final procedural value of 259 s. No reversion of anticoagulation was performed and no intraprocedural and peri-procedural complications occurred. The patient was then carefully transferred to the ward bed with the aid of a sliding mat; a mandatory 4 h bed rest and immobilization was prescribed.
At the time of femoral vein haemostasis (4 h after PVI completion), the ACT was 110 s; rivaroxaban (20 mg) was then administered. In the following hours, the patient developed right gluteal and bilateral lumbar pain, right lower limb paraesthesia, and motor deficits below the knee [patellar and achillean hyporeflexia; iliopsoas, quadriceps, ankle dorsiflexors, plantar flexors, and long toe extensors motor deficits (MMT 2)]. A psoas sign was also present. The neurological symptoms fluctuated presenting an on-off pattern intermittently affecting either the right or left lower limb; there was the suspicion for either a transient central or peripheral involvement. A complete thoracic, chest, and cerebral angio-computed tomography scan was performed and acute retroperitoneal or cerebral bleeding were excluded.
Furthermore, a cervical, dorsal, and lumbar native magnetic resonance imaging was then performed. This examination showed a subdural spinal haematic collection with an associated epidural component from L3 to S2 (8 Â 11 mm in the axial plane, see Figure 1; 65 Â 11 mm in the sagittal plane, see Figure 2). The subdural spinal haematoma exerted compression over the dural sheath, abolishing the liquoral representation around the cauda equina lateral right nerve roots within L3-L4 and L4-L5 and within L5-S1 mainly in the posterior bilateral location.
After consultation with neurologists and neurosurgeons, a 'waitand-see' treatment approach by withholding anticoagulation therapy and patient immobilization was taken. Indeed, the operative risk of subsequent lower limb paralysis associated to the surgical approach was estimated too high and exceeding possible benefit. In the following 9 days, a neurological rehabilitation and sub-therapeutic anticoagulation regimen was initiated. There was progressive recovery of sensorial and motor deficits. After 5 months though, the patient still presented residual lower limb motor deficits necessitating the support of a walking stick.

Discussion
To our knowledge, this is the first case of spontaneous spinal subdural bleeding observed after a PVI procedure.   Although this complication has never been reported following PVI, it emphasizes the need of careful evaluation of multimorbidity patients and of possible muscle-skeletal changes beyond the pathologies included in the HAS-BLED score.
Oral anticoagulation was interrupted 36 h before the procedure; this was in agreement with the 2017 HRS/EHRA/APHRS/SOLAECE recommendations 12 , when the procedure was performed. Subsequently, recommendations by scientific societies 13 changed into uninterrupted DOACs at the time of PVI. Although speculative, during uninterrupted DOACs (in cases when CHA 2 DS 2 -VASc > _3, availability of cardiac imaging assessment at procedural time) or interrupted within 12-24 h, the bleeding risk in a patient could even be higher than that assessed by the HAS-BLED score. Indeed, anatomic conditions may increase the bleeding risk and are not part of the HAS-BLED score.
Vascular complications are the most frequent procedure-related adverse events following PVI procedure. These include generic haematoma of the groin, retroperitoneal haematoma, pseudoaneurysm, arteriovenous fistula, and hemothorax (subclavian or internal jugular venous access) with an incidence in the range of 1-2% 3 . Periprocedure anticoagulation regimen seems to be an important factor in the occurrence of these complications.
Intracranial severe spontaneous bleeding complications are rare after PVI (incidence of 0.3 1 ). However, as described in the present case, such complications may cause invalidating and irreversible body injury which may be particularly limitative in more compromised patients. As observed in the present case, even careful procedural planning with guidelines recommendations of peri-procedural anticoagulation management did not prevent a severe CNS bleeding adverse event. [2][3] Spinal cord bleeding is a unique condition with significant disabling consequences. It is classified based on the primary location of bleeding into intramedullary (haematomyelia), subarachnoid haemorrhage (SAH), subdural haemorrhage, and epidural haemorrhage. It requires emergency investigation and treatment. [4][5][6] Based on the existing literature spinal vascular malformations such as intradural arteriovenous malformations are the most common cause of atraumatic intramedullary spinal cord haemorrhage. Additional causative factors include warfarin or heparin anticoagulation, hereditary or acquired bleeding disorders, primary spinal cord tumours, spinal cord metastases, or a delayed complication of spinal radiation [7][8][9][10][11] .
Onset may vary with sudden, severe back or neck pain and sometimes radicular or with rapidly progressive flaccid quadri/biparesis, with subsequent ventilatory failure reported in cases where bleeding involves the cervical and superior dorsal spine. Magnetic resonance imaging with and without gadolinium is the gold standard neurological imaging modality. There are no clinical trials to guide the management of acute intramedullary spinal cord haemorrhage, and subsequent treatment is usually directed towards the underlying cause. Early surgical treatment is always indicated when the patient's neurological status progressively deteriorates with severe central complications (such as ventilatory failure) but also conservative treatment is possible, whenever neurological impairment is minimal and selflimiting.

Conclusion
In conclusion, for the first time spinal subdural bleeding after PVI is reported. Careful peri-procedural management of anticoagulation therapy as well as assessment of patient bleeding risk are mandatory. Little is known on the predisposing factors that could identify which patients may be at risk of bleeding complications such as that reported in this case.

Lead author biography
Giacomo Maria Cioffi, 34, raised in Lugano (CH), works for Cardiocentro Ticino as resident in Cardiology since 2018, with special interest in Electrophysiology.

Supplementary material
Supplementary material is available at European Heart Journal -Case Reports online.
Slide sets: A fully edited slide set detailing this case and suitable for local presentation is available online as Supplementary data.

Consent:
The author/s confirm that written consent for submission and publication of this case report including image(s) and associated text has been obtained from the patient in line with COPE guidance.