BACKGROUND AND OBJECTIVES The relationship between QT prolongation and myocardial ischemia is widely known. Due to the limited value of ST depression, we aimed to evaluate, by using four simpler heart rate corrections (Bazett, Framingham, Fridericia and Hodges), the value of maximal exercise-QTc prolongation in the diagnosis of coronary artery disease (CAD) presence and severity. SUBJECTS AND...

The purpose of this study was to determine the effect of muscle mass and the level of force on the contraction-induced rise in heart rate. We conducted an experimental study in a sample of 28 healthy men between 20 and 30 yr of age (power: 95%, alpha: 5%). Smokers, obese subjects, and those who performed regular physical activity over a certain amount of energetic expenditure were excluded from...

Background The increasing use of ketamine as a potential rapid-onset antidepressant necessitates a better understanding of its effects on blood pressure and heart rate, well-known side effects at higher doses. For the subanesthetic dose used for depression, potential predictors of these cardiovascular effects are important factors influencing clinical decisions. Since ketamine influences the sy...

OBJECTIVE Outcome of staged palliation for hypoplastic left heart syndrome has improved over the past decades. However, only little is known about the exercise capacity of children with palliated hypoplastic left heart syndrome where a systemic right ventricle supports the systemic circulation. The aim of the study was to assess exercise capacity in a contemporary cohort of children with hypopl...

biharmonic surfaces in euclidean space $mathbb{e}^3$ are firstly studied from a differential geometric point of view by bang-yen chen, who showed that the only biharmonic surfaces are minimal ones. a surface $x : m^2rightarrowmathbb{e}^{3}$ is called biharmonic if $delta^2x=0$, where $delta$ is the laplace operator of $m^2$. we study the $l_k$-biharmonic spacelike hypersurfaces in the $4$-dimen...

in this paper we show that if q is a power of a prime p , then the projective special linear group psl(2, q) and the stabilizer of a point of the projective line have maximum sum element orders among all proper subgroups of projective general linear group pgl(2, q) for q odd and even respectively

OBJECTIVES To observe the relationship between chest pain/dyspnoea-heart rate during exertion in patients with angiographically proved Coronary artery disease compared to patients having negative Exercise Tolerance Test in a private and public sector hospital. METHODS This is an observational two centre study from Karachi in which 150 patients referred for Exercise ToleranceTest (ETT) at Ziau...

The insulin-like and vasodilatatory polypeptide relaxin (RLX), formerly known as a pregnancy hormone, has gained interest as a potential humoral mediator in human heart failure. Controversy exists about the relation between plasma levels of RLX and the severity of heart failure. The present study was designed to determine the course of RLX, atrial, and brain natriuretic peptide (NT-proANP and N...

In 50 patients with ischaemic heart disease prospective analyses of the reproducibility of exercise tests at 3-month intervals were performed. The same method of testing was used repeatedly in a smaller group of patients 3 or more times at 6- to 8-week intervals. No significant differences were found in maximal heart rate, maximal systolic blood pressure, rate-pressure product, and total work. ...

The measurement of heart rate (HR) during acute exercise is one of the most common and pragmatic methods for estimating exercise intensity and prescribing exercise training thresholds [2, 17], although some studies suggest that the linear relationship between HR and oxygen consumption is sometimes altered [5]. Similarly, heart rate recovery following acute maximal or sub-maximal exercise is a c...