Journal of the American College of Cardiology
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J. Am. Coll. Cardiol. · Mar 1998
Likelihood of spontaneous conversion of atrial fibrillation to sinus rhythm.
We sought to determine the likelihood and predictors of spontaneous conversion to sinus rhythm of recent-onset atrial fibrillation (symptoms <72 h). ⋯ Spontaneous conversion to sinus rhythm occurs in almost 70% of patients presenting with atrial fibrillation of <72-h duration. Presentation with symptoms of <24-h duration is the best predictor of spontaneous conversion.
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J. Am. Coll. Cardiol. · Mar 1998
Twenty-four hour time domain heart rate variability and heart rate: relations to age and gender over nine decades.
This study sought to define the effects of age and gender effects on the normal range of time domain heart rate variability (HRV) over nine decades in healthy subjects. ⋯ 1) Using all measures, HRV of healthy subjects declines with aging, with measure-dependent patterns. 2) Using the SDNN index, rMSSD and pNN50, HRV of healthy subjects, particularly those >65 years old, may decrease to below levels associated with increased risk of mortality. 3) Gender influences HRV. Gender differences in HRV are age and measure dependent. 4) Age and gender also affect heart rate.
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J. Am. Coll. Cardiol. · Feb 1998
Multicenter Study Comparative Study Clinical TrialTime to positivity of a rapid bedside assay for cardiac-specific troponin T predicts prognosis in acute coronary syndromes: a Thrombolysis in Myocardial Infarction (TIMI) 11A substudy.
We sought to determine whether the rapid bedside assay for troponin T identified patients at risk for a more complicated hospital stay and a higher rate of adverse clinical events. ⋯ A positive rapid assay for troponin T at presentation identifies those patients at risk for higher rates of adverse clinical events and longer, more complicated hospital stays. Stratification of patients by time to development of a positive rapid assay identifies those patients at highest mortality risk.
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J. Am. Coll. Cardiol. · Feb 1998
Comparative StudySystematic direct angioplasty and stent-supported direct angioplasty therapy for cardiogenic shock complicating acute myocardial infarction: in-hospital and long-term survival.
This prospective observational study was conducted to examine the apparent impact of a systematic direct percutaneous transluminal coronary angioplasty (PTCA) strategy on mortality in a series of 66 consecutive patients with acute myocardial infarction (AMI) complicated by cardiogenic shock, and to analyze the predictors of outcome after successful direct PTCA. ⋯ Systematic direct PTCA, including stent-supported PTCA, can establish a Thrombolysis in Myocardial Infarction (TIMI) grade 3 flow in the great majority of patients presenting with AMI and early cardiogenic shock. High performance criteria, including new devices such as coronary stents, should be considered in randomized trials where mechanical revascularization therapy is being tested.
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J. Am. Coll. Cardiol. · Feb 1998
Comparative StudyComparative effects of isoproterenol and dopamine on myocardial oxygen consumption, blood flow distribution and total body oxygen consumption in conscious lambs with and without an aortopulmonary left to right shunt.
We sought to study the effects of catecholamines on myocardial oxygen consumption (VO2), regional blood flows and total body VO2 in lambs with circulatory congestion. ⋯ We conclude that the catecholamines isoproterenol and dopamine do not lead to a mismatch between myocardial oxygen supply and demand, nor do they change blood flow distribution unfavorably in 7-week old lambs with a left to right shunt. We demonstrated that isoproterenol is superior to dopamine, because it shifts the balance between oxygen supply and consumption toward supply so that systemic oxygen extraction reserve increases.