Stroke ranks as the third leading cause of death and the leading cause of serious long-term disabilities in the U.S., according to the American Heart Association (AHA). Direct and indirect costs of stroke were $40.9 billion in 2007, with ischemic stroke having an individual lifetime cost of about $140,000. With the development of acute stroke centers, outcomes are improving for patients. By monitoring for stroke risk factors, such as atrial fibrillation, neurologists now can intervene before a second stroke occurs.
Where to admit?
While stroke patients often are hard to monitor and manage, many argue that which hospital unit takes care of these patients could drastically impact outcomes, particularly in detecting cardiac abnormalities.
In 2003, Geert A. Sulter, MD, a neurologist at Academic Hospital Groningen in Groningen, The Netherlands, and colleagues confirmed in a pilot study what many stroke specialists had reported anecdotally: Patients with a diagnosis of acute ischemic stroke who were admitted to a stroke-care monitoring unit had better outcomes than patients placed in a conventional stroke unit (Stroke 2003;34:101-104). Patients in the monitoring unit were continuously monitored for at least 48 hours for body temperature, oxygen saturation, blood pressure and cardiac rhythm using a five-lead electrocardiogram to allow immediate intervention, if indicated. In the conventional stroke unit, measurements were taken manually four times a day. The researchers found that cardiac monitoring detected newly diagnosed atrial fibrillation (AF) in 18 percent of patients in the stroke-care monitoring unit compared with only 3 percent of patients in the conventional stroke unit.
Also in 2003, Michael J. Schneck, MD, director of the neuro-intensive care program at Loyola University Health System in Maywood, Ill., was helping to establish a stroke unit at the suburban Chicago hospital using the Brain Attack Coalition's published recommendations as a blueprint (JAMA 2000;283:3102-3109). To justify adding comprehensive monitoring to Loyola's program, he and colleagues designed a study based on data on 337 stroke patients between 2003 and 2004 to determine what additional information is gained through telemetry.
"I felt strongly that stroke patients might have undetected cardiac abnormalities," Schneck says. "We found that roughly 20 percent of the patients who came in had an abnormal rhythm, which was either undetected or different from the reading when they were admitted."
Making monitoring mainstream
Those who survive an initial stoke are at high risk of recurrence, with 5 to 12 percent of patients likely to experience a second stroke within a year. AF is considered a significant risk factor for a second stroke, making detection and management of arrhythmias critical to short- and long-term survival.
In 2005, the Brain Attack Coalition added continuous cardiac and respiratory monitoring to its updated recommendations, based on Sulter et al's findings. Loyola's Stroke Center now provides continuous monitoring with telemetry for virtually all stroke patients, and has been certified by the Joint Commission as a Primary Stroke Center (PSC). The Brain Attack Coalition estimates there are 700 Joint Commission-accredited PSCs across the U.S., and another 200 hospitals with state-certified PSCs (Stroke 2010;41;1100-1101).
|Risk Factors for Ischemic Stroke & Systemic
Embolism in Patients With Nonvalvular Atrial Fibrillation
|Risk Factors||Relative Risk|
|Previous stroke or TIA*||2.5|
|History of hypertension||1.6|
|Advanced age (continuous, per decade)||1.4|
|Data derived from collaborative analysis of five untreated control
groups in primary prevention trials. As a group, patients with
nonvalvular atrial fibrillation (AF) carry about a six-fold increased
risk of thromboembolism compared with patients in sinus rhythm.
Relative risk refers to comparison of patients with AF to patients
without these risk factors.
*TIA indicates transient ischemic attack.
Continuous monitoring allows neurologists to pick up transient cardiac abnormalities that otherwise could go undetected. Patients receive an electrocardiogram at admission, but unless a condition such as AF or atrial flutter is present at that time, it will not be recorded. Also, asymptomatic patients may develop arrhythmia during their hospitalization. If identified, the condition can be appropriately