Identification and Management of Periprocedure Stroke in the Electrophysiology Laboratory

Understanding Stroke Risk

Any type of invasive cardiology procedure presents risks for stroke; however, electrophysiology (EP) procedures provide a unique set of circumstances. Not only does the invasive procedure itself include risks of clot formation or plaque embolization from the use and manipulation of guide wires and catheters, but generally, patients undergoing EP studies have existing arrhythmias as well, most often atrial fibrillation (AF). The risk for stroke during EP procedures can range from 1% to 5% depending on the procedure type, the presence of arrhythmia, and any patient co-existing conditions such as advanced age, hypertension, and/or heart failure. A published study of periprocedural cerebrovascular accidents (CVA) during EP determined that of the CVA events that occurred in the study participants, 53% were intraprocedural, while 47% occurred postprocedurally. Of all events, 95% were ischemic and 95% occurred during ablation procedures.¹ Thus, those patients undergoing ablation procedures for AF are at the highest risk for a neurological event.

Patient Assessment Challenges

Knowing that EP patients carry a heightened risk, it is important to have a baseline assessment of the patient’s neurological status and a grasp of any co-conditions that can further increase that risk. While typical immediate preprocedure assessment in the EP lab does not necessarily include a full neurological assessment, it is imperative that, particularly for AF ablation procedures, staff members pay close attention to the patient’s baseline condition and provide detailed documentation of any neurological deficiencies prior to the procedure. This documentation can prove valuable post procedure as a means to verify the lack of any neurological event during the procedure. Observation and evaluation of the patient’s cognitive ability, verbalization, and movement of extremities provides a solid baseline for postprocedure comparison. 

One way to quickly identify a high-risk patient is use of the CHA₂DS₂-VASc scoring tool.² Although the tool is often used to determine the level of anticoagulation required in patients with non-valvular AF, Corazon advocates its use as an assessment of overall stroke risk in these patients. The tool’s name is actually a mnemonic using the major stoke risk factors for AF patients as seen in Figure 1. Each item, with the exception of stroke/TIA and age 75 or older, is valued at one point, while these two risk factors are valued at two points. For each risk factor present in the patient, points are assigned and then totaled. For “0” points, the patient is considered overall low risk, one point equates to intermediate risk, and two or more points is considered high risk. Calculating the score prior to an EP procedure for ablation can, at the very least, provide a very high-level assessment regarding that patient and his/her risk during the procedure.

Present in this mix of performing an invasive procedure on a stroke risk patient is the issue of anticoagulation therapy…should it be continued during the procedure or discontinued prior? Unfortunately, there are no definitive directives or guidelines regarding the discontinuation of anticoagulation preprocedure, the use of any “bridging” anticoagulant protocol intraprocedure, or follow-up anticoagulation. Also, with a wider range of anticoagulants now available, knowing the best approach to anticoagulation during an EP procedure is more complex than ever. The electrophysiologist will give great consideration to whether or not anticoagulation should be provided during EP procedures, and if so, which type is best. The quandary is weighing the risk of hemorrhagic stroke if anticoagulation is continued versus the risk of embolic stoke if anticoagulation is discontinued.

If there is a concern the patient is experiencing a neurological event, either intraprocedure or postprocedure, a comparison of the patient’s current condition with the baseline evaluation should be obtained as soon as possible. This will provide insight into whether the patient condition is worsening. Keep in mind, though, that neurological events occurring during invasive cardiology procedures are often transient and may resolve within four to eight hours. Regardless of the potential that the event may be transient, immediate evaluation of the neurological deficits should occur. One of the most critical questions asked when a deficit is noted is whether the event is thrombotic or hemorrhagic. Typically, at the onset of any neurological deficits, an immediate CT scan and early involvement of the neurologist is instrumental in deciding the best patient care approach moving forward, specifically any decisions regarding ongoing anticoagulation. The neurologist can provide the best insight as to stroke etiology, thrombotic or hemorrhagic, and direct the ongoing care accordingly. 

Likewise, the organization’s stroke coordinator or stroke team can play an important role for assessment and ongoing evaluation of the patient using the National Institute of Health Stroke Scale (NIHSS). Corazon recommends a formal stroke assessment be completed as soon as possible after neurological deficit is noted.

Stroke Care Delivery and Assessment Tools

Corazon has long been committed to understanding the way stroke care is delivered, and completed a survey in partnership with the National Stroke Association (NSA) on the usage trends of the NIHSS. Survey results supported Corazon’s belief that significant opportunities exist to improve stroke care in hospitals across the country in the application of this assessment. The need for inter-rater reliability and consistent application of the assessment tool for multiple scenarios was an issue clearly identified in the survey. In addition, the need for ongoing education and competency evaluations in the application of this complex tool is even more important in the cath/EP lab due to the limited clinical need for its use in that setting. Caregivers at all stages of the EP continuum need to be ever vigilant related to recognition of neurological complications, and further, in understanding how to manage any complications, including stroke, in the procedural setting. 

Ensuring appropriate response within adequate time for a stroke complication in the EP lab can be a difficult goal to achieve…though a non-negotiable one, nonetheless. It is critical that the EP team be educated and trained on the appropriate procedures for this time-sensitive patient population. This can be a challenge as the time and resources for education continue to be at a premium for many, if not all, healthcare providers.

 Tools that can assist with this goal are limited, which is why Corazon developed Cerebros, an IT application, to assist clinicians with better management of stroke patients in any/all clinical settings. Within the application, assessment tools for NIHSS, the CHA₂DS₂-VASc for TIA, and a variety of hemorrhagic stroke assessments (e.g., Hunt and Hess, Fisher, Ogilvy and Carter, etc.) are readily available for clinicians. The NIHSS assessment tool has a function that allows the user to toggle on instructions as seen in Figure 2. 

Corazon recommends that caregivers, regardless of the availability of technology supports such as Cerebros, have resources available to ensure consistent care processes and tools to support stroke assessment. Likewise, we strongly encourage ongoing education for caregivers in the procedural cath/EP lab setting in the application of these assessment tools, as their use in a time-sensitive event such as stroke can quite literally mean the difference between life and death. 

Using IT to Support Performance Improvement in the EP Lab

Our team’s national experience in multiple service lines underscores the power of clinical outcomes information. For instance, significant data has long been available in the diagnostic cath and interventional procedural areas through participation in vehicles such as the American College of Cardiology - National Cardiovascular Data Registry (ACC-NCDR^™). Other than the device registries such as the NCDR’s ICD Registry^™ in the EP lab, there is not a corollary national benchmarking source for patients undergoing mapping and ablation procedures, who may be more prone to stroke complications. Our team advises EP labs to develop internal dashboards to track clinical outcomes, including complications such as stroke.

Additionally, procedural areas can participate in the ongoing evaluation of the delivery of stroke services by tracking and evaluating the important time-to-treatment metrics that they strive to meet once a stroke has been identified in the EP lab setting. Similar to the care of the patient experiencing an acute myocardial infarction (AMI) — time is of the essence in stroke care — and the importance of a standardized approach has proven critical to meeting time-to-treatment benchmarks and achieving consistent quality outcomes. Clinicians within the EP lab setting who are attuned to important time metrics in cardiac care can make similar contributions to the early recognition and treatment of stroke.

Typically the hospital’s stroke coordinator can be a resource in educating staff in procedural areas related to stroke complications and a standardized approach to meeting time-to-treatment benchmarks. Likewise, the coordinator can be a resource for stroke complication tracking and can provide assistance with any performance improvement process that needs to be initiated based on ongoing performance within the EP lab setting. Our team recommends that all strokes be tracked as part of program review, even though inpatient strokes are not required to be tracked by some external review agencies.

Managing the EP Lab Quality Data Requirements

Outcomes tracking in the EP lab, including stroke and other complications, is an important function and must have resources committed to the effort. An important exercise in order to quantify the burden of data collection for any clinical service is to log or track the work effort of those involved in the process. To get an accurate and complete picture of the effort, the time for the collection of data for all individuals involved in the process must be accounted for. The next step would be to quantify the labor costs associated with the average monthly or annual time requirements by full-time equivalent (FTE) for each employee type. This analysis can help administrators identify the true cost of any data requirements such as ICD registry participation, and can be used as a baseline to determine any potential cost savings that can be achieved through the addition of technology. 

Corazon’s experience across many service lines reveals that there are significant costs associated with program data demands. Many clinical programs are mired in manual data management processes, and are largely completing abstraction and analysis retrospectively. The challenge for the EP service is to understand opportunities for real-time process improvement across the full acute care continuum. Additionally, it can be beneficial to tap into other hospital resources such as the stroke coordinator and any IT systems and resources they may use to get a picture of the “slice” of data that is pertinent to the EP patients treated. We believe programs that harness the power of information technology and clinical-decision analytics can transform the delivery of care across their organizations.

References

1. Harb SC, Thomas G, Saliba WI, et al. Characteristics, treatment and outcomes of periprocedural cerebrovascular accidents during electrophysiologic procedures. J Interv Card Electrophysiol. 2013;37(1):41-46.
2. Medi C, Hankey GJ, Freedman SB. Stroke risk and antithrombotic strategies in atrial fibrillation. Stroke. 2010;41(11):2705-2713.