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Evidence for fractal correlation properties in variations of peripheral arterial tone during REM sleep. Am J Physiol Heart Circ Physiol 283: H434-H439, 2002. First published March 7, 2002; 10.1152/ajpheart.00336.2001 .--Previous studies utilizing detrended fluctuation analysis (DFA) of heart rate variability during sleep revealed a higher fractal exponent during rapid eye movement (REM) sleep than non-REM sleep. The aim of this study was to determine whether the same difference exists in the variations of peripheral arterial tone (PAT). Finger pulse wave measured by a novel plethysmographic technique was monitored during sleep in 12 chronic heart failure patients, 8 heavy snorers, and 12 healthy volunteers. For each subject, at least two 15-min time series were constructed from the interpulse intervals and from pulse wave amplitudes during REM and non-REM sleep. Fractal scaling exponents of both types of time series were significantly higher for REM than non-REM sleep in all groups. In each of the groups and in both sleep stages, the fractal scaling exponents based on pulse wave amplitude were significantly higher than those based on pulse rate variability. A repeat of the analysis for short-, intermediate-,and long-term intervals revealed that the fractallike exponents were evident only in the short- and intermediate-term intervals. Because PAT is a surrogate of sympathetic activation, our results indicate that variations in sympathetic activation during REM sleep have a fractallike behavior. detrended fluctuation analysis; congestive heart failure; heavy snoring

Aims: Endothelial function is impaired in advanced chronic heart failure (ACHF) patients. We explored a possible association between endothelial function and subsequent mortality risk in ACHF. Methods and Results: We prospectively assessed brachial flow-mediated dilation (FMD) in 82 consecutive New York Heart Association class IV ischaemic ACHF patients with a mean left ventricular ejection fraction (LVEF) of 22 +/- 3%. Following overnight fasting and discontinuation of all medications for > or = 12 h, percent increase in FMD (%FMD) and nitroglycerin-mediated vasodilation were assessed using linear array ultrasound. All patients were followed for 14 +/- 2 months for adverse cardiovascular events, including death, hospitalization for CHF exacerbation, or myocardial infarction. Patients were divided into two groups: those with an FMD lesser than or equal to the median %FMD of 4.6% (n = 41) and those with an FMD above the median (n = 41). Both groups were comparable regarding cardiovascular risk factors, LVEF, and concomitant medications. During follow-up, 22 (53.6%) patients with FMD lesser than or equal to the median had composite adverse cardiovascular events compared with only eight patients (19.5%) with FMD above the median (P < 0.01). Furthermore, fiver deaths (12.1%) occurred in patients with FMD lesser than or equal to the median, compared with no deaths in patients with FMD above the median (P < 0.03). Cox regression analyses revealed that FMD was an independent predictor for these events. Conclusion: Flow-mediated dilation is associated with increased mortality risk in ischaemic ACHF patients. [ABSTRACT FROM AUTHOR]

Unlike thrombolytic agents, there are conflicting data regarding the time-dependent effect of aspirin treatment on outcome in acute myocardial infarction (AMI). We sought to evaluate the impact of timing of aspirin administration (before vs after thrombolysis) on mortality of patients with AMI. Our study included 1,200 patients with ST elevation AMI treated with thrombolysis. Early (n = 364) versus late (n = 836) users were defined as those receiving emergency aspirin before versus after initiation of thrombolysis, respectively. Time (median) from symptom onset to initiation of aspirin treatment was significantly shorter in early versus late users (1.6 vs 3.5 hours; p <0.001). There were no significant differences between the 2 groups with respect to baseline clinical characteristics. Early aspirin users were more likely to develop reischemia, to be treated with beta blockers, to be referred to coronary angiography, percutaneous transluminal coronary angioplasty, or coronary artery bypass graft surgery. Early users experienced lower mortality at 7 days (2.5% vs 6.0%, p = 0.01), 30 days (3.3% vs 7.3%, p = 0.008), and 1 year (5.0% vs 10.6%, p = 0.002) than late users. This survival benefit persisted for patients with and without previous aspirin therapy or revascularization and after adjustment for baseline characteristics and therapies at 7 days (odds ratio 0.36, 95% confidence interval 0.15 to 0.79), at 30 days (odds ratio 0.39, 95% confidence interval 0.17 to 0.82), and at 1 year (odds ratio 0.41, 95% confidence interval 0.21 to 0.74). Our study proposes a time-dependent benefit from aspirin in patients with AMI treated with thrombolysis. [ABSTRACT FROM AUTHOR]

Failed thrombolysis in acute myocardial infarction (AMI) patients is associated with a high risk of morbidity and mortality. Rescue or salvage percutaneous transluminal coronary angioplasty (PTCA) in this group of patients is still controversial. We report our experience with early emergency angiography and rescue PTCA in 27 patients who were hemodynamically unstable or had a large area of myocardium at risk after failed thrombolysis. Rescue PTCA was successful in 95% of attempted PTCA. Three patients were referred to emergency CABG. Early ‘rescue angiography’ with or without rescue PTCA after failed thrombolysis in a selected patient population, is an important tool for early risk stratification and decision-making during the hyperacute phase of AMI, while it may also serve in restoring coronary artery patency of the infarct-related artery with a high success rate. [ABSTRACT FROM AUTHOR]

We report on a 40 year old woman who presented with typical unstable angina pectoris associated with pulmonary oedema, due to poorly controlled hyperthyroidism. No cardiac abnormality was detected by echo-Doppler and nuclear ventriculography. Coronary angiography demonstrated normal coronary arteries. This case represents a new manifestation of the known association of cardiac ischaemia with hyperthyroidism in the presence of normal coronary arteries. [ABSTRACT FROM AUTHOR]