Diagnostic accuracy of carotid plaque magnetic resonance imaging compared to histopathology in symptomatic carotid artery stenosis.

INTRODUCTION: Vulnerable plaques have been shown to predict ipsilateral cerebral ischemic events and identifying them leads to appropriate secondary stroke prevention strategies. We evaluated the diagnostic accuracy of MR carotid plaque imaging in identifying plaque vulnerability when compared with histopathological findings in patients with symptomatic carotid stenosis who underwent carotid endarterectomy (CEA). METHODS: A prospective cohort of forty-five consecutive patients with moderate to severe symptomatic carotid stenosis who underwent CEA at a tertiary Indian hospital had 3 T MRI plaque imaging with multi-parametric protocol between November 2021 and December 2022. Images were analyzed by a vascular radiologist blinded to histopathological data. High-risk plaque characteristics such as lipid rich necrotic core (LRNC), intraplaque hemorrhage (IPH), thin fibrous cap and ulceration were assessed and correlated with histopathological findings as per American Heart Association (AHA) classification using Cohen's kappa statistics to obtain diagnostic accuracies. RESULTS: Of the 45 patients, 38(84 %) were males. The mean age was 65 ± 7.7 years and mean duration to CEA from the most recent event was 57 days (57 ± 46 days). A significant correlation between MR plaque imaging and histopathology was noted for IPH (sensitivity-91 %, specificity-86 %, κ = 0.774, p < 0.001), LRNC (sensitivity-92.1 %, specificity-85.7 %, κ = 0.697, p < 0.001), and plaque ulceration (sensitivity-84.6 %, specificity-78.1 %, κ = 0.563, p < 0.001). MRI had an overall sensitivity and specificity of 92.3 % and 84.2 % respectively (κ = 0.77, p < 0.001) in discriminating high risk plaques. CONCLUSION: MR plaque imaging shows a very good correlation with histopathology and can identify unstable high-risk plaques with high accuracy. This may have implication in selection of patients for carotid revascularization in symptomatic carotid stenosis.

Thrombolysis for Ischemic Stroke Despite Recent Ingestion of Direct Oral Anticoagulants - A Growing Dilemma Also in India.

The administration of intravenous thrombolysis (IVT) for patients with acute ischemic stroke who have recently ingested direct oral anticoagulants (DOACs) presents a clinical challenge due to the perceived increased risk of intracranial hemorrhage (ICH). Traditional guidelines from the US and European authorities advise against IVT within 48 h of last DOAC ingestion, unless specific coagulation tests indicate safety. However, emerging observational studies suggest that IVT might be safe in selected patients. A US stroke registry study and a global multicenter cohort study both reported no significant increase in symptomatic ICH among patients on DOACs compared to those not on anticoagulants. A systematic review of all published observational studies further supported these findings, showing comparable bleeding rates and functional outcomes in DOAC-treated patients. Reversal agents like idarucizumab for dabigatran have demonstrated potential in facilitating safer IVT administration, though logistical and cost-related barriers limit their widespread use. The variability in global guidelines reflects differing approaches to risk assessment and resource availability, highlighting the need for individualized treatment decisions. In India, the increasing prevalence of atrial fibrillation and stroke as well as prescription of DOACs necessitate adapted guidelines that consider local health-care infrastructure. Despite the promising observational data, the lack of randomized controlled trials underscores the need for further research to establish robust evidence for IVT use in this context. Collaborative international efforts and inclusion of diverse patient populations in future studies will be crucial to refine treatment protocols and improve outcomes for stroke patients on DOACs.

Primary Angiitis of the CNS: Differences in the Profile Between Subtypes and Outcomes From an Indian Cohort.

BACKGROUND AND OBJECTIVES: Primary angiitis of the CNS (PACNS) is a rare disease that has significant morbidity and mortality. Subtypes of PACNS can have different presentations that could be missed with certain diagnostic modalities, further increasing diagnostic complexity. We sought to distinguish the subtypes of PACNS and describe their outcomes in an Indian cohort. METHODS: Adult patients in this retrospective single-center cohort study were reviewed from the PACNS database between 2000 and 2019. Diagnosis was made as per Calabrese and Malleck criteria. Small and medium vessel vasculitis was defined, and their clinical and radiologic profile, treatment, and outcomes were compared. Functional outcomes were noted at 6-month, 1-year, and at last follow-up, while relapses were noted at last follow-up. A poor outcome was defined as modified Rankin Scale >2. RESULTS: Seventy-two patients fulfilled the inclusion criteria of whom 50 (69.4%) were male. The small vessel vasculitis subtype had a younger age at onset (30.5 vs 40.5 years, p = 0.014), presented less often as a stroke (22% vs 62%, p = 0.001), and had greater delay in diagnosis and treatment initiation (median of 620 days vs 118 days, p = 0.001) compared with medium vessel vasculitis subtype. Although no difference was noted at 6 months, the small vessel vasculitis group had poor outcomes at 1-year and last follow-up (57% vs 20%, p = 0.011 and 72% vs 34%, p = 0.005, respectively) and had more relapses at last follow-up (89% vs 30%, p < 0.001) when compared with the medium vessel vasculitis group. On analyzing the entire cohort, 50 of 72 (69%) and 37 of 53 (69.8%) patients had a good outcome at 6 months and 1 year, respectively. Relapse was noted in 35 of 72 (49%) at final follow-up. The choice of the treatment regimen did not predict outcomes or relapses. DISCUSSION: The small vessel vasculitis subtype of PACNS is a distinct entity that has diagnostic and treatment delays with poor long-term outcomes and more relapses. Recognizing the different subtypes of PACNS may help to expedite diagnosis and plan treatment.