Long QT syndrome (LQTS) is a heritable disease associated with ECG QT interval prolongation, ventricular tachycardia, and sudden cardiac death in young patients. Among genotyped individuals, mutations in genes encoding repolarizing K + channels (LQT1:KCNQ1; LQT2:KCNH2) are present in approximately 90% of affected individuals. Expression of pore mutants of the human genes KCNQ1 (KvLQT1-Y315S) and KCNH2 (HERG-G628S) in the rabbit heart produced transgenic rabbits with a long QT phenotype. Prolongations of QT intervals and action potential durations were due to the elimination of I Ks and I Kr currents in cardiomyocytes. LQT2 rabbits showed a high incidence of spontaneous sudden cardiac death (>50% at 1 year) due to polymorphic ventricular tachycardia. Optical mapping revealed increased spatial dispersion of repolarization underlying the arrhythmias. Both transgenes caused downregulation of the remaining complementary I Kr and I Ks without affecting the steady state levels of the native polypeptides. Thus, the elimination of 1 repolarizing current was associated with downregulation of the reciprocal repolarizing current rather than with the compensatory upregulation observed previously in LQTS mouse models. This suggests that mutant KvLQT1 and HERG interacted with the reciprocal wild-type α subunits of rabbit ERG and KvLQT1, respectively. These results have implications for understanding the nature and heterogeneity of cardiac arrhythmias and sudden cardiac death.
Aims The COVID-19 pandemic required a significant redeployment of worldwide healthcare resources. Fear of infection, national lockdowns and altered healthcare priorities have the potential to impact utilisation of healthcare resources for non-communicable diseases. To survey health professionals’ views of the impact of the COVID-19 pandemic on the rate and timing of admission of patients with ST-elevation myocardial infarction (STEMI), the European Society of Cardiology (ESC) administered an internet-based questionnaire to cardiologists and cardiovascular nurses across 6 continents. Methods and results 3101 responses were received from 141 countries across 6 continents. 88.3% responded that their country was in “total lockdown” and 7.1% in partial lockdown. 78.8% responded that the number of patients presenting with STEMI was reduced since the coronavirus outbreak and 65.2% indicated that the reduction in STEMI presentations was >40%. Approximately 60% of all respondents reported that STEMI patients presented later than usual and 58.5% that >40% of STEMI patients admitted to hospital presented beyond the optimal window for primary percutaneous intervention (PCI) or thrombolysis. Independent predictors of the reported higher rate of delayed STEMI presentation were a country in total lockdown, >100 COVID-19 cases admitted locally, and the complete restructuring of the local cardiology service. Conclusion The survey indicates that the impact of COVID-19 on STEMI presentations is likely to be substantial, with both lower presentations and a higher rate of delayed presentations occurring. This has potentially important ramifications for future healthcare and policy planning in the event of further waves of this pandemic.
ImportanceSARS-CoV-2 infection is associated with persistent, relapsing, or new symptoms or other health effects occurring after acute infection, termed postacute sequelae of SARS-CoV-2 infection (PASC), also known as long COVID. Characterizing PASC requires analysis of prospectively and uniformly collected data from diverse uninfected and infected individuals.ObjectiveTo develop a definition of PASC using self-reported symptoms and describe PASC frequencies across cohorts, vaccination status, and number of infections.Design, Setting, and ParticipantsProspective observational cohort study of adults with and without SARS-CoV-2 infection at 85 enrolling sites (hospitals, health centers, community organizations) located in 33 states plus Washington, DC, and Puerto Rico. Participants who were enrolled in the RECOVER adult cohort before April 10, 2023, completed a symptom survey 6 months or more after acute symptom onset or test date. Selection included population-based, volunteer, and convenience sampling.ExposureSARS-CoV-2 infection.Main Outcomes and MeasuresPASC and 44 participant-reported symptoms (with severity thresholds).ResultsA total of 9764 participants (89% SARS-CoV-2 infected; 71% female; 16% Hispanic/Latino; 15% non-Hispanic Black; median age, 47 years [IQR, 35-60]) met selection criteria. Adjusted odds ratios were 1.5 or greater (infected vs uninfected participants) for 37 symptoms. Symptoms contributing to PASC score included postexertional malaise, fatigue, brain fog, dizziness, gastrointestinal symptoms, palpitations, changes in sexual desire or capacity, loss of or change in smell or taste, thirst, chronic cough, chest pain, and abnormal movements. Among 2231 participants first infected on or after December 1, 2021, and enrolled within 30 days of infection, 224 (10% [95% CI, 8.8%-11%]) were PASC positive at 6 months.Conclusions and RelevanceA definition of PASC was developed based on symptoms in a prospective cohort study. As a first step to providing a framework for other investigations, iterative refinement that further incorporates other clinical features is needed to support actionable definitions of PASC.
The present study examines the relationship between systemic hypoperfusion via cardiac output (CO) and neuropsychological performances emphasizing executive function in an aging cohort. Geriatric outpatients with treated, stable cardiovascular disease (CVD) and no history of neurological illness (n=72, ages 56-85) were administered cognitive measures with an emphasis on executive functioning. Echocardiogram findings were used to stratify participants into two groups: low CO (<4.0 L/min) and normal CO (> o r=4.0 L/min). Between-group comparisons were made using ANCOVAs adjusting for systolic blood pressure. The low CO group performed significantly worse than the normal CO group on DKEFS Tower Test and DKEFS Trail Making Test. No significant between-group differences were noted for any of the other cognitive indices. Findings suggest that reduced CO is associated with poorer executive functioning among geriatric outpatients with stable CVD, as the cognitive profile emphasizes a relationship between systemic hypoperfusion and problems with sequencing and planning. The executive dysfunction profile may be secondary to reduced blood flow to vulnerable subcortical structures implicated in frontal-subcortical circuitry.
Background and Purpose-The presence of white matter hyperintensities on brain MRI is common among elderly individuals. Previous research suggests that cardiovascular risk factors are associated with increased white matter hyperintensities. Examining the role of direct physiological measures of vascular function will help to clarify the vascular mechanisms related to white matter hyperintensities. The aim of the present study was to examine the association between endothelial-dependent and endothelial-independent vasodilatation and white matter hyperintensity volume. Methods-Twenty-five older adults with a range of cardiovascular diseases underwent brain MRI and completed assessments of blood vessel integrity using endothelial-dependent and independent flow-mediated dilation of the brachial artery. A semi-automated pixel-based method was used to quantify total brain volume and white matter hyperintensity volume, with white matter hyperintensity volume corrected for total brain volume. The association between measures of flow-mediated dilation and log-transformed white matter hyperintensities was examined. Results-Correlation analysis revealed that endothelial-dependent vasodilatation was significantly and inversely associated with white matter hyperintensity volume. In contrast, endothelial-independent vasodilatation was not associated with white matter hyperintensities. Neither endothelial-dependent nor endothelial-independent vasodilatation was associated with total brain volume. Conclusions-These data provide preliminary evidence that the integrity of the vascular endothelium is associated with white matter hyperintensities in older adults with cardiovascular disease. Impaired vascular function may be one mechanism that contributes to the development of white matter hyperintensities in the brain. Additional longitudinal research combining measures of vessel function, neuroimaging and cognition will be helpful in clarifying this potential mechanism. (Stroke. 2007;38:308-312.)
OBJECTIVES-To preliminarily examine the association between cardiac output, a measure of systemic blood flow, and structural brain magnetic resonance imaging indices of white matter hyperintensities (WMHs). DESIGN-Cross-sectional. SETTING-University medical setting.PARTICIPANTS-Thirty-six older adults without dementia with prevalent cardiovascular disease (aged 56-85). MEASUREMENTS-Cardiac output, WMHs.RESULTS-Partial correlations, adjusting for age and history of hypertension, yielded an inverse relationship between WMHs adjacent to subcortical nuclei and cardiac output (correlation coefficient = −0.48, P = .03); as cardiac output decreased, WMHs increased significantly. No significant associations were found between cardiac output and total WMHs or periventricular WMHs.CONCLUSION-These preliminary data suggest that systemic blood flow, measured according to cardiac output, is inversely associated with WMHs adjacent to the subcortical nuclei. Cerebrovascular degeneration and the chronicity of hypoperfusion may exacerbate the susceptibility of white matter integrity to alterations in blood flow in older adults. © 2007, The American Geriatrics SocietyAddress correspondence to Angela L. Jefferson, PhD, Alzheimer's Disease Center, Boston University School of Medicine, 715 Albany Street, B-7800, Boston, MA 02118. E-mail: E-mail: angelaj@bu.edu. Author Contributions: Angela L. Jefferson: study concept and design, acquisition of participants, data analysis and interpretation, preparation of manuscript; David F. Tate: study concept, data interpretation, preparation of manuscript; Athena Poppas: acquisition of participants, data interpretation, preparation of manuscript; Adam M. Brickman: study concept and design, data interpretation, preparation of manuscript; Robert H. Paul and John Gunstad: acquisition of participants, preparation of manuscript; Ronald A. Cohen: study concept and design, acquisition of participants, preparation of manuscript.A portion of these data were presented at the 34th annual meeting of the International Neuropsychological Society, Boston, Massachusetts, February 2006. Cardiac output, a measure of systemic perfusion, is one cardiovascular variable that has received less attention but may be an important risk factor for cognitive aging and WMHs. Cardiac output is a measure of forward stroke volume that reflects the amount of blood exiting the heart measured in liters per minute (L/min). There are autoregulatory mechanisms that augment blood flow to the brain at the expense of muscle tissue and other organs during critical moments of sudden reductions in systemic blood flow (e.g., cardiac arrest), 12 although such autoregulatory mechanisms may be less effective when reductions in systemic blood flow are chronic. Furthermore, these mechanisms may change as a function of age-associated vasculature breakdown. Examination of the relationships between reduced cardiac output and regional distributions of WMHs may yield important information regarding systemic blood flow as a possible risk facto...
The American College of Cardiology third decennial Professional Life Survey was completed by 2,313 cardiologists: 964 women (42%) and 1,349 men (58%). Compared with 10 and 20 years ago, current results reflect a substantially lower response rate (21% vs. 31% and 49%, respectively) and an aging workforce that is less likely to be in private practice. Women continue to be more likely to practice in academic centers, be pediatric cardiologists, and have a noninvasive subspecialty. Men were more likely to indicate that family responsibilities negatively influenced their careers than previously, whereas women remained less likely to marry or have children. Men and women reported similar, high levels of career satisfaction, with women reporting higher satisfaction currently. However, two-thirds of women continue to experience discrimination, nearly 3 times the rate in men. Personal life choices continue to differ substantially for men and women in cardiology, although differences have diminished.
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