Questionnaire and Portable Sleep Test Screening of Sleep Disordered Breathing in Acute Stroke and TIA.

Sleep disordered breathing (SDB) is highly prevalent, but frequently unrecognized among stroke patients. Polysomnography (PSG) is difficult to perform soon after a stroke. We evaluated the use of screening questionnaires and portable sleep testing (PST) for patients with acute stroke, subarachnoid hemorrhage, or transient ischemic attack to expedite SDB diagnosis and management. We performed a single-center retrospective analysis of a quality improvement study on SDB screening of consecutive daytime, weekday, adult admissions to a stroke unit. We excluded patients who were unable to communicate and lacked available family members. Patients were screened with the Epworth Sleepiness Scale, Berlin Questionnaire, and STOP-BANG Questionnaire and underwent overnight PST and/or outpatient PSG. The 4-item STOP Questionnaire was derived from STOP-BANG for a secondary analysis. We compared the sensitivity and specificity of the questionnaires for the diagnosis of at least mild SDB (apnea hypopnea index (AHI) ≥5) on PST and correlated AHI measurements between PST and PSG using the Spearman correlation. Out of sixty-eight patients included in the study, 54 (80%) were diagnosed with SDB. Only one (1.5%) had a previous SDB diagnosis. Thirty-three patients completed all questionnaires and a PST. The STOP-BANG questionnaire had the highest sensitivity for at least mild SDB (0.81, 95% CI (confidence interval): 0.65-0.92) but a low specificity (0.33, 95% CI 0.10, 0.65). The discrimination of all questionnaires was overall poor (C statistic range 0.502-0.640). There was a strong correlation (r = 0.71) between the AHI results estimated using PST and outpatient PSG among 28 patients. The 4-item STOP Questionnaire was the easiest to administer and had a comparable or better sensitivity than the other questionnaires. Inpatient PSTs were useful for screening in the acute setting to facilitate an early diagnosis of SDB and to establish further outpatient evaluations with sleep medicine.

Stress cardiomyopathy induced during dobutamine stress echocardiography.

BACKGROUND: Catecholamines play a central role in pathogenesis of stress cardiomyopathy (SC). We aimed to review the clinical characteristics, procedural details and outcomes of patients with SC during dobutamine stress echocardiography (DSE). METHODS/RESULTS: A total of 20 adults [age 64±15 years, 80% women, 67% hypertension, 20% diabetes, 33% hypercholesterolemia, 19% chronic kidney disease, 13% known anxiety disorder] with SC during DSE were identified from local digital archives of our laboratory (n=3) or reports in English literature (n=17). Indication for DSE was suspected coronary artery disease (CAD) in all patients. Left ventricular (LV) ejection fraction was normal at baseline. SC developed at a blood pressure of 154±47/86±24 mmHg, heart rate of 130±17 bpm (88±10% predicted maximum) and peak rate-pressure product of 20559±3898 mmHg*bpm. ST segment elevation was seen in 65%. SC occurred at peak dobutamine infusion rate of 38±6 µg/kg/min in 85% and during recovery in 15%. Atropine [0.7±0.6 (0.25-2) mg] was given to 7 patients. LV ejection fraction dropped to 30±6% with apical (40%), apical and mid (45%) or basal and mid (10%) circumferential LV ballooning. One patient (5%) had a mixed pattern of wall motion abnormality. LV outflow tract obstruction developed in 15%. Major adverse cardiac events occurred in 7 (35%) and included death (n=1), congestive heart failure (n=2), hypotension (n=3) and atrial fibrillation with heart failure (n=1). At a mean follow up duration of 19±19 days, complete or partial recovery of LV wall motion abnormality was seen in 18 and 1 patient, respectively. CONCLUSION: SC uncommonly occurs during DSE. However, death and other adverse events (hypotension, heart failure and atrial fibrillation) may occur and require urgent attention. Once managed, complete recovery is expected in most patients.

Recent trends in hospital admissions and outcomes of cardiac Chagas disease in the United States.

BACKGROUND: Chagas disease (CD), caused by Trypanosoma cruzi, has been increasingly encountered as a cause of cardiovascular disease in the United States. We aimed to examine trends of hospital admissions and cardiovascular outcomes of cardiac CD (CCD). METHODS: Search of 2003-2011 Nationwide Inpatient Sample database identified 949 (age 57±16 years, 51% male, 72.5% Hispanic) admissions for CCD. RESULTS: A significant increase in the number of admissions for CCD was noted during the study period (OR=1.054; 95% CI=1.028-1.081; P< 0.0001); 72% were admitted to Southern and Western hospitals. Comorbidities included hypertension (40%), coronary artery disease (28%), hyperlipidemia (26%), tobacco use (12%), diabetes (9%), heart failure (5%) and obesity (2.2%). Cardiac abnormalities noted during hospitalization included atrial fibrillation (27%), ventricular tachycardia (23%), sinoatrial node dysfunction (5%), complete heart block (4%), valvular heart disease (6%)] and left ventricular aneurysms (5%). In-hospital mortality was 3.2%. Other major adverse events included cardiogenic shock in 54 (5.7%), cardiac arrest in 30 (3.2%), acute heart failure in 88 (9.3%), use of mechanical circulatory support in 29 (3.1%), and acute stroke in 34 (3.5%). Overall, 63% suffered at least one adverse event. Temporary (2%) and permanent (3.5%) pacemakers, implantable cardioverter defibrillators (10%), and cardiac transplant (2.1%) were needed for in-hospital management. CONCLUSIONS: Despite the remaining concerns about lack of awareness of CCD in the US, an increasing number of hospital admissions were reported from 2003-2011. Serious cardiovascular abnormalities were highly prevalent in these patients and were frequently associated with fatal and nonfatal complications.

Dopamine D1 sensitivity in the prefrontal cortex predicts general cognitive abilities and is modulated by working memory training.

A common source of variance (i.e., "general intelligence") underlies an individual's performance across diverse tests of cognitive ability, and evidence indicates that the processing efficacy of working memory may serve as one such source of common variance. One component of working memory, selective attention, has been reported to co-vary with general intelligence, and dopamine D1 signaling in prefrontal cortex can modulate attentional abilities. Based on their aggregate performance across five diverse tests of learning, here we characterized the general cognitive ability (GCA) of CD-1 outbred mice. In response to a D1 agonist (SKF82958, 1 mg/kg), we then assessed the relationship between GCA and activation of D1 receptor (D1R)-containing neurons in the prelimbic region of the medial prefrontal cortex, the agranular insular cortex, and the dorsomedial striatum. Increased activation of D1R-containing neurons in the prelimbic cortex (but not the agranular insular cortex or dorsomedial striatum) was observed in animals of high GCA relative to those of low GCA (quantified by c-Fos activation in response to the D1 agonist). However, a Western blot analysis revealed no differences in the density of D1Rs in the prelimbic cortex between animals of high and low GCA. Last, it was observed that working memory training promoted an increase in animals' GCA and enhanced D1R-mediated neuronal activation in the prelimbic cortex. These results suggest that the sensitivity (but not density) of D1Rs in the prelimbic cortex may both regulate GCA and be a target for working memory training.

Voluntary aerobic exercise increases the cognitive enhancing effects of working memory training.

Increases in performance on tests of attention and learning are often observed shortly after a period of aerobic exercise, and evidence suggests that humans who engage in regular exercise are partially protected from age-related cognitive decline. However, the cognitive benefits of exercise are typically short-lived, limiting the practical application of these observations. Here, we explored whether physical exercise might induce lasting changes in general cognitive ability if that exercise was combined with working memory training, which is purported to broadly impact cognitive performance. Mice received either exercise treatment (6 weeks of voluntary running wheel access), working memory training (in a dual radial-arm maze), both treatments, or various control treatments. After this period of exercise, working memory training was initiated (alternating with days of exercise), and continued for several weeks. Upon completion of these treatments, animals were assessed (2-4 weeks later) for performance on four diverse learning tasks, and the aggregate performance of individual animals across all four learning tasks was estimated. Working memory training alone promoted small increases in general cognitive performance, although any beneficial effects of exercise alone had dissipated by the time of learning assessments. However, the two treatments in combination more than doubled the improvement in general cognitive performance supported by working memory training alone. Unlike the transient effects that acute aerobic exercise can have on isolated learning tasks, these results indicate that an acute period of exercise combined with working memory training can have synergistic and lasting impact on general cognitive performance.