Predictive value of sleep apnea screenings in cardiac surgery patients.

INTRODUCTION: Obstructive sleep apnea (OSA) is a highly prevalent disorder associated with increased cardiovascular risks. We explored the predictive value of OSA screening instruments in cardiac disease patients awaiting cardiac surgery. METHODS: In this prospective cohort, 107 participants awaiting cardiac surgery from Cleveland Clinic and Johns Hopkins underwent polysomnography after completing Epworth Sleepiness Scale (ESS), Sleep Apnea/Sleep Disorder Questionnaire (SA/SDQ), STOP, STOPBAG2 and Berlin questionnaires. Score comparisons between groups based on apnea-hypopnea index (AHI) ≥15 were performed. Logistic regression with receiver operating characteristic (ROC) analysis was used to investigate optimal threshold. RESULTS: Prevalence of OSA (AHI ≥5) was 71.9% (77/107) and 51 (47.7%) had moderate-to-severe disease (AHI ≥15). Participants were primarily male (57%) and Caucasian (76.6%). Mean age was 67.3 ± 13.3 years and BMI was 26.5 ± 6.6. Of the five screening tools, STOPBAG2 with a cut-point of 0.381 provided 78% sensitivity and 38% specificity (AUC 0.66, 95%CI 0.55-0.77). SA/SDQ yielded a cut-point of 32 for all subjects (AUC: 0.62, 95%CI 0.51-0.73) with sensitivity and specificity of 60% and 62% respectively, while STOP score ≥2 provided sensitivity and specificity of 67% and 52% respectively (AUC: 0.61, 95%CI 0.51-0.72). Among STOP items, "observed apnea" had the strongest correlation with AHI ≥15 (OR 3.67, 95%CI 1.57-8.54, p = 0.003). The ESS and Berlin were not useful in identifying moderate-to-severe OSA. CONCLUSION: Common screening tools had suboptimal performance in cardiac surgery patients. STOPBAG2 was better at predicting the probability of moderate-to-severe OSA in patients undergoing cardiac surgery compared to ESS, SA/SDQ, STOP and Berlin questionnaires.

The varicella zoster virus vasculopathies: clinical, CSF, imaging, and virologic features.

BACKGROUND: Varicella zoster virus (VZV) vasculopathy produces stroke secondary to viral infection of cerebral arteries. Not all patients have rash before cerebral ischemia or stroke. Furthermore, other vasculitides produce similar clinical features and comparable imaging, angiographic, and CSF abnormalities. METHODS: We review our 23 published cases and 7 unpublished cases of VZV vasculopathy. All CSFs were tested for VZV DNA by PCR and anti-VZV IgG antibody and were positive for either or both. RESULTS: Among 30 patients, rash occurred in 19 (63%), CSF pleocytosis in 20 (67%), and imaging abnormalities in 29 (97%). Angiography in 23 patients revealed abnormalities in 16 (70%). Large and small arteries were involved in 15 (50%), small arteries in 11 (37%), and large arteries in only 4 (13%) of 30 patients. Average time from rash to neurologic symptoms and signs was 4.1 months, and from neurologic symptoms and signs to CSF virologic analysis was 4.2 months. CSF of 9 (30%) patients contained VZV DNA while 28 (93%) had anti-VZV IgG antibody in CSF; in each of these patients, reduced serum/CSF ratio of VZV IgG confirmed intrathecal synthesis. CONCLUSIONS: Rash or CSF pleocytosis is not required to diagnose varicella zoster virus (VZV) vasculopathy, whereas MRI/CT abnormalities are seen in almost all patients. Most patients had mixed large and small artery involvement. Detection of anti-VZV IgG antibody in CSF was a more sensitive indicator of VZV vasculopathy than detection of VZV DNA (p < 0.001). Determination of optimal antiviral treatment and benefit of concurrent steroid therapy awaits studies with larger case numbers.

Risk factors for early visual deterioration in temporal arteritis.

BACKGROUND: Despite corticosteroid treatment, patients with temporal arteritis may continue to lose vision. However, predictors of progressive visual loss are not known. METHODS: We retrospectively reviewed 341 consecutive patients with suspected temporal arteritis who underwent temporal artery biopsy. 90 patients with biopsy proven temporal arteritis were included in our study. RESULTS: Twenty-one patients (23%) experienced continuous visual symptoms despite steroid therapy and 14 among these suffered persistent visual deterioration. Based on univariate analysis, visual loss on presentation was associated with disc swelling and a history of hypertension. Risk factors for progressive visual loss included older age, elevated C reactive protein and disc swelling. CONCLUSION: Although corticosteroid therapy improves the visual prognosis in temporal arteritis, steroids may not stop the progression of visual loss. Our study reliably establishes the risk factors for visual loss in this serious condition. Whether addressing these risk factors early in their presentation can alter the visual outcome remains unknown. Individual risk anticipating treatment regimens and strategies might improve the visual prognosis in temporal arteritis in the future.

The cost of pneumonia after acute stroke.

OBJECTIVE: To determine the incremental costs of pneumonia occurring during hospitalization for stroke. METHODS: We reviewed hospital records of all Medicare patients admitted for ischemic or hemorrhagic stroke to 29 hospitals in a large metropolitan area, 1991 through 1997, excluding those who died or had do not resuscitate orders written within 3 days of admission. Hospital costs of patients with stroke were determined using Medicare Provider Analysis and Review data after adjustment for baseline factors affecting cost and propensity for pneumonia. Secondary analyses examined the risk-adjusted relationship of pneumonia to discharge disposition. RESULTS: Pneumonia occurred in 5.6% (635/11,286) of patients with stroke, and was more common among patients admitted from nursing homes and those with greater severity of illness (p < 0.001). Mean adjusted costs of hospitalization for patients with stroke with pneumonia were $21,043 (95% CI $19,698 to 22,387) and were $6,206 (95% CI $6,150 to 6,262) for patients without pneumonia, resulting in an incremental cost of $14,836 (95% CI $14,436 to 15,236). Patients with pneumonia were over 70% more likely to be discharged with requirements for extended care (adjusted OR 1.73, 95% CI 1.32 to 2.26). CONCLUSION: Extrapolated to the over 500,000 similar patients hospitalized for stroke in the United States, the annual cost of pneumonia as a complication after acute stroke is approximately $459 million.

The value of detecting anti-VZV IgG antibody in CSF to diagnose VZV vasculopathy.

BACKGROUND: Factors that may obscure the diagnosis of varicella zoster virus (VZV) vasculopathy include the absence of rash before TIAs or stroke as well as similar clinical features and imaging, angiographic, and CSF abnormalities to those of other vasculopathies. Diagnosis relies on virologic confirmation that detects VZV DNA, anti-VZV IgG antibody, or both in the CSF. METHODS: We reviewed our current 14 cases of patients diagnosed with VZV vasculopathy based on combined clinical, imaging, angiographic, or CSF abnormalities. All CSFs must have been tested for VZV DNA by PCR and for anti-VZV IgG antibody by enzyme immunoassay and found to be positive for either or both. Of the 14 subjects, 8 had a history of recent zoster, whereas 6 had no history of zoster rash before developing vasculopathy. RESULTS: All 14 subjects (100%) had anti-VZV IgG antibody in their CSF, whereas only 4 (28%) had VZV DNA. The detection of anti-VZV IgG antibody in CSF was a more sensitive indicator of VZV vasculopathy than detection of VZV DNA (p < 0.001). CONCLUSIONS: In varicella zoster virus (VZV) vasculopathy, the diagnostic value of detecting anti-VZV IgG antibody in CSF is greater than that of detecting VZV DNA. Although a positive PCR for VZV DNA in CSF is helpful, a negative PCR does not exclude the diagnosis of VZV vasculopathy. Only when the CSF is negative for both VZV DNA and anti-VZV IgG antibody can the diagnosis of VZV vasculopathy be excluded.

The effect of pneumonia on mortality among patients hospitalized for acute stroke.

OBJECTIVE: To determine the effect of pneumonia on 30-day mortality in patients hospitalized for acute stroke. METHODS: Subjects in the initial cohort were 14,293 Medicare patients admitted for stroke to 29 greater Cleveland hospitals between 1991 and 1997. The relative risk (RR) of pneumonia for 30-day mortality was determined in a final cohort (n = 11,286) that excluded patients dying or having a do not resuscitate order within 3 days of admission. Clinical data were obtained from chart abstraction and were merged with Medicare Provider Analysis and Review files to obtain deaths within 30 days. A predicted-mortality model (c-statistic = 0.78) and propensity score for pneumonia (c-statistic = 0.83) were used for risk adjustment in logistic regression analyses. RESULTS: Pneumonia was identified in 6.9% (n = 985) of all patients and in 5.6% (n = 635) of the final cohort. The rates of pneumonia were higher in patients with greater stroke severity and features indicating general frailty. Unadjusted 30-day mortality rates were six times higher for patients with pneumonia than for those without (26.9% vs 4.4%, p < 0.001). After adjusting for admission severity and propensity for pneumonia, RR of pneumonia for 30-day death was 2.99 (95% CI 2.44 to 3.66), and population attributable risk was 10.0%. CONCLUSION: In this large community-wide study of stroke outcomes, pneumonia conferred a threefold increased risk of 30-day death, adding impetus to efforts to identify and reduce the risk of pneumonia in patients with stroke.

Cooling for acute ischemic brain damage (cool aid): an open pilot study of induced hypothermia in acute ischemic stroke.

BACKGROUND AND PURPOSE: Hypothermia is effective in improving outcome in experimental models of brain infarction. We studied the feasibility and safety of hypothermia in patients with acute ischemic stroke treated with thrombolysis. METHODS: An open study design was used. All patients presented with major ischemic stroke (National Institutes of Health Stroke Scale [NIHSS] score >15) within 6 hours of onset. After informed consent, patients with a persistent NIHSS score of >8 were treated with hypothermia to 32+/-1 degrees C for 12 to 72 hours depending on vessel patency. All patients were monitored in the neurocritical care unit for complications. A modified Rankin Scale was measured at 90 days and compared with concurrent controls. RESULTS: Ten patients with a mean age of 71.1+/-14.3 years and an NIHSS score of 19.8+/-3.3 were treated with hypothermia. Nine patients served as concurrent controls. The mean time from symptom onset to thrombolysis was 3.1+/-1.4 hours and from symptom onset to initiation of hypothermia was 6.2+/-1.3 hours. The mean duration of hypothermia was 47.4+/-20.4 hours. Target temperature was achieved in 3.5+/-1.5 hours. Noncritical complications in hypothermia patients included bradycardia (n=5), ventricular ectopy (n=3), hypotension (n=3), melena (n=2), fever after rewarming (n=3), and infections (n=4). Four patients with chronic atrial fibrillation developed rapid ventricular rate, which was noncritical in 2 and critical in 2 patients. Three patients had myocardial infarctions without sequelae. There were 3 deaths in patients undergoing hypothermia. The mean modified Rankin Scale score at 3 months in hypothermia patients was 3.1+/-2.3. CONCLUSION: Induced hypothermia appears feasible and safe in patients with acute ischemic stroke even after thrombolysis. Refinements of the cooling process, optimal target temperature, duration of therapy, and, most important, clinical efficacy, require further study.

Safety of intra-arterial thrombolysis in the postoperative period.

BACKGROUND AND PURPOSE: Limited systemic fibrinolysis and reduced dosage are features of intra-arterial thrombolyis (IAT) that may be advantageous in the treatment of postoperative strokes. However, IAT may increase the risk of surgical bleeding. We sought to determine the safety of postoperative IAT. METHODS: This was a retrospective case series from 6 university hospitals. All cases of IAT within 2 weeks of surgery were identified. Demographics, stroke mechanism, stroke severity, imaging and angiographic findings, time between surgery and lysis, thrombolytic agent used, surgical site bleeding, intracranial bleeding, and mortality rates were determined. Death or complications directly related to IAT were determined. RESULTS: Thirty-six patients (median age, 71.5 years; range, 45 to 85) were identified. Median time from surgery to stroke was 21.5 hours (range, 1 to 120). Open heart surgery was done in 18 (50%), carotid endarterectomy in 6 (17%), craniotomy in 3 (8%), ophthalmologic-ear, nose and throat surgery in 2 (6%), urologic-gynecologic surgery in 4 (11%), orthopedic surgery in 2 (6%), and plastic surgery in 1 (3%). The stroke causes were cardioembolism in 24 (67%), large-vessel atherosclerosis in 4 (11%), dissection in 3 (8%), postendarterectomy occlusion in 4 (11%), and radiation arteriopathy in 1 (3%). Median time to angiogram was 2.5 hours (0.1 to 5.5). Occlusion sites were M1 in 19 (53%), M2 in 9 (25%), internal carotid artery in 5 (14%), basilar artery in 2 (6%), and posterior communicating artery in 1 (3%). Thrombolysis was completed at a median of 4.5 hours (range, 1 to 8.0). Tissue plasminogen activator was used in 19 (53%) and urokinase in 17 (47%). Nine (26%) patients died. Surgical site bleeding occurred in 9 (25%) cases (minor in 6, major in 3). The major surgical bleeds were 2 post-craniotomy intracranial hemorrhages and 1 hemopericardium after coronary artery bypass grafting; all were fatal. Six deaths were non-IAT related: 3 caused by cerebral edema and 3 by systemic causes. Major bleeding complications were significantly more common among patients with craniotomy (P<0.02). CONCLUSIONS: Postoperative IAT carries a risk of bleeding in up to 25% of patients but is usually minor surgical site bleeding. Avoiding IAT in intracranial surgery patients may reduce complications. Mortality rate in this series was similar to that reported in prior IAT trials. IAT remains a viable therapeutic option for postoperative strokes.

Community use of intravenous tissue plasminogen activator for acute stroke: results of the brain matters stroke management survey.

BACKGROUND AND PURPOSE: Little is known of neurologists' viewpoints regarding intravenous tPA use or institutional readiness to evaluate potential thrombolytic candidates. METHODS: Surveys were distributed at the Brain Matters Stroke Management Workshops held in 16 cities in the United States. RESULTS: Intravenous tPA was administered by 46.9% of responding neurologists. Almost 30% (29.9%) of surveyed neurologists were "very convinced" of its efficacy, whereas 61.6% were "very concerned" about the risk of intracranial hemorrhage. Only half of the respondents believed their institutions could meet all NINDS-recommended stroke-evaluation time targets. CONCLUSIONS: Neurologists' enthusiasm for the efficacy of intravenous tPA is tempered by their concern about intracranial hemorrhage. Institutional readiness for evaluating acute stroke patients is not optimized.

Safety and efficacy of intraarterial thrombolysis for perioperative stroke after cardiac operation.

BACKGROUND: Acute ischemic stroke after cardiac operations is a devastating complication with limited therapeutic options. As clinical trials of thrombolysis for acute ischemic stroke exclude patients with recent major surgery, the safety of intraarterial thrombolysis in this setting is unknown. METHODS: Thirteen patients with acute ischemic stroke within 12 days of cardiac operation underwent intraarterial thrombolysis within 6 hours of stroke symptom onset. The National Institutes of Health Stroke Scale was used to assess neurologic recovery. RESULTS: The mean age was 69 years (standard deviation +/-5 years) and 62% were men. Cardiac procedures included valve operations in 6 patients, coronary artery bypass grafting in 4, valve and coronary artery bypass grafting in 2, and left ventricular assist device in 1 patient. Atrial fibrillation occurred in 5 patients (38%). The mean time from operation to stroke was 4.3 days (standard deviation +/- 3 days). Thrombolysis was initiated within 3.6 hours (standard deviation +/-1.6 hours) of stroke symptom onset. Recanalization was complete in 1 patient, partial in 5, and 7 patients had low flow. Neurologic improvement occurred in 5 patients (38%). One patient needed a chest tube for hemothorax, 2 others were transfused for low hemoglobin. No operative intervention for bleeding was necessary. CONCLUSIONS: In select patients with acute ischemic stroke after recent cardiac operation, intraarterial thrombolysis appears to be reasonably safe and may lead to neurologic recovery.

Stent-assisted angioplasty of intracranial vertebrobasilar atherosclerosis: an initial experience.

OBJECT: Patients with intracranial vertebrobasilar artery (VBA) atherosclerotic occlusive disease have few therapeutic options. Unfortunately, VBA transient ischemic attacks (TIAs) herald a lethal or devastating event within 5 years in 25 to 30% of patients. The authors report their initial experience with eight patients in whom medically refractory TIAs secondary to intracranial posterior circulation atherosclerotic occlusive lesions were treated with stent-assisted angioplasty. METHODS: Eight patients (six men), ranging in age from 43 to 77 years, experienced signs and symptoms of VBA insufficiency despite combination therapy with warfarin and antiplatelet agents. Angiographic studies revealed severe distal vertebral (four patients), proximal basilar (one patient), or proximal and midbasilar stenoses (three patients). Aspirin and clopidogrel were administered for 3 days before primary angioplasty and stent placement, and this regimen was maintained by the patients on discharge. Patients underwent heparinization during the procedure and were given a bolus and 12-hour infusion of abciximab. A neurologist specializing in stroke evaluated all patients before and after the procedure. The VBAs in all patients were successfully revascularized with 7 to 28% residual stenosis. Six patients experienced no neurological complications. One patient died the evening of the procedure due to a massive subarachnoid hemorrhage. Two patients had groin hematomas, one developed congestive heart failure, and one had transient encephalopathy. All surviving patients are asymptomatic up to 8 months postoperatively. CONCLUSIONS: Although primary intracranial VBA angioplasty with stent insertion is technically feasible, complications associated with the procedure can be life threatening. As experience is gained with this procedure, it may be offered routinely as an alternative therapy to patients with medically refractory posterior circulation occlusive disease that may develop into catastrophic VBA insufficiency.

Use of tissue-type plasminogen activator for acute ischemic stroke: the Cleveland area experience.

CONTEXT: Little is known regarding outcomes after intravenous tissue-type plasminogen activator (IV tPA) therapy for acute ischemic stroke outside a trial setting. OBJECTIVE: To assess the rate of IV tPA use, the incidence of symptomatic intracerebral hemorrhage (ICH), and in-hospital patient outcomes throughout a large urban community. DESIGN: Historical prospective cohort study conducted from July 1997 through June 1998. SETTING: Twenty-nine hospitals in the Cleveland, Ohio, metropolitan area. PATIENTS: A total of 3948 patients admitted to a study hospital with a primary diagnosis of ischemic stroke (International Classification of Diseases, Ninth Revision, Clinical Modification code 434 or 436). MAIN OUTCOME MEASURES: Rate of IV tPA use and occurrence of symptomatic ICH among patients treated with tPA; proportion of patients receiving tPA whose treatment deviated from national guidelines; in-hospital mortality among patients receiving tPA compared with that among ischemic stroke patients not receiving tPA and with mortality predicted by a model. RESULTS: Seventy patients (1.8%) admitted with ischemic stroke received IV tPA. Of those, 11 patients (15.7%; 95% confidence interval [CI], 8.1%-26.4%) had a symptomatic ICH (of which 6 were fatal) and 50% (95% CI, 37.8%-62.2%) had deviations from national treatment guidelines. In-hospital mortality was significantly higher among patients treated with tPA (15.7%) compared with patients not receiving tPA (5.1%, P<.001) and compared with the model's prediction (7.9%; P<.006). CONCLUSIONS: A small proportion of patients admitted with acute ischemic stroke in Cleveland received tPA; they experienced a high rate of ICH. Cleveland community experience with tPA for acute ischemic stroke may differ from that reported in clinical trials.

Intra-arterial thrombolysis for perioperative stroke after open heart surgery.

Recent major surgery is an exclusion criterion for thrombolysis. Six patients with acute ischemic stroke underwent intra-arterial thrombolysis after recent open heart surgery without clinically significant bleeding complications, although one patient developed a small, asymptomatic cerebellar hemorrhage. Intra-arterial thrombolysis may be an option for patients with cerebral embolism in the perioperative period.