Trends in Utilization of Magnetic Resonance Imaging for Stroke Patients With Cardiac Rhythm Devices

Background and Purpose

Magnetic resonance imaging (MRI) is safe for most patients with cardiovascular implantable electronic devices (CIEDs). However, patients presenting with acute ischemic stroke or transient ischemic attack (AIS/TIA) who have CIEDs may undergo MRI less frequently than patients without devices. We assessed contemporary use of MRI for patients with AIS/TIA and the effect of a recent coverage revision by the Center for Medicare and Medicaid Services (CMS) on MRI utilization.

Methods

Using Optum® claims data from January 2012 to June 2019, we performed an interrupted time series analysis of MRI utilization during AIS/TIA hospitalizations with the April 2018 CMS coverage revision serving as the intervention. For patients treated after the coverage revision, we used multivariable logistic regression to determine the association between lack of CIED and MRI utilization for AIS/TIA.

Results

We identified 417,899 patient hospitalizations for AIS/TIA, of which 30,425 (7%) had a CIED present (CIED vs non-CIED patients: age 77.6 ± 9.8 vs 72.7 ± 12.3 years; 45.5% vs 54.3% female). From 2012 to 2019, annual MRI utilization increased from 3% to 20% for CIED patients and 58% to 66% for non-CIED patients. The CMS coverage revision was associated with a 4.2% absolute additional increase in MRI utilization for CIED patients. Non-CIED patients treated after the CMS coverage revision were substantially more likely than CIED patients to undergo MRI (adjusted OR 6.7, 95% CI: 6.3-7.1, P<.001).

Conclusions

MRI utilization has increased for stroke patients with CIEDs but remains far lower than in similar patients without devices.

Tilt-Corrected Region Boundaries May Enhance the Alberta Stroke Program Early Computed Tomography Score for Less Experienced Raters

BACKGROUND

The Alberta Stroke Program Early Computed Tomography Score (ASPECTS) is widely used to quantify early ischemic changes in the anterior circulation but has limited inter-rater reliability.

AIMS

We investigated whether application of 3-dimensional boundaries outlining the ASPECTS regions improves inter-rater reliability and accuracy.

METHODS

We included all patients from our DEFUSE 2 database who had a pretreatment noncontrast computed tomography scan (NCCT) of acceptable quality. Six raters (2 neuroradiologists, 2 vascular neurologists, and 2 neurology residents) scored ASPECTS of each NCCT without ("CT-native") and with the superimposed boundary template ("CT-template"). Gold-standard ASPECTS were generated by the 2 neuroradiologists through joint adjudication. Inter-rater reliability and accuracy were assessed using the intraclass correlation coefficient (ICC) for full-scale agreements and Gwet's AC1 for dichotomized (ASPECTS 0-6 vs 7-10) agreements.

RESULTS

Eighty-two patients were included. Inter-rater reliability improved with higher training level for both CT-native (ICC = .15, .31, .54 for residents, neurologists, and radiologists, respectively) and CT-template (ICC = .18, .33, .56). Use of the boundary template improved correlation with the gold-standard for one resident on full-scale agreement (ICC increased from .01 to .31, P = .01) and another resident on dichotomized agreement (AC1 increased from .36 to .64, P = .01), but resulted in no difference for other raters. The template did not improve ICC between raters of the same training level.

CONCLUSIONS

Inter-rater reliability of ASPECTS improves with physician training level. Standardized display of ASPECTS region boundaries on NCCT does not improve inter-rater reliability but may improve accuracy for some less experienced raters.

A survey-based analysis of symptoms in patients with postural orthostatic tachycardia syndrome

Postural orthostatic tachycardia syndrome (POTS) is a type of dysautonomia seen most commonly in young women and children. It is defined as an increase in heart rate of 30 beats per minute (bpm) or more within 10 minutes of standing in adults, or by 40 bpm or more in children in the absence of orthostatic hypotension. In addition to typical autonomic symptoms, POTS patients report a wide range of subjective complaints in multiple organ systems, though the exact frequencies are unclear. To address the symptom frequency, we had 39 patients with POTS at our institution complete an intake form consisting of a list of 37 symptoms. The most frequently reported symptoms included palpitations, lightheadedness, and headache, although sleep disturbances, gastrointestinal complaints, sensitivity to temperature, and rash were also common.