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BACKGROUND:

Echocardiographic evaluation of the heart and its function, especially left ventricular systolic function, has great clinical importance. Systolic function can be measured using several methods, such as the amplitude of motion of the left atrioventricular plane (mitral annulus motion [MAM]) toward the apex during systole. Similarly, right ventricular systolic function can be measured using the motion of the right atrioventricular plane (tricuspid annulus motion [TAM]) toward the apex during systole.

OBJECTIVES:

Because the mitral and tricuspid annuli are situated close to each other in the fibrous skeleton between both ventricles and atria, one might think that a decrease in the amplitude of MAM would be followed by a decrease in the amplitude of TAM. The present study was developed to determinine if this anatomical intimacy causes a good correlation between the amplitudes of TAM and MAM.

METHODS:

Nineteen healthy subjects and 103 consecutive patients were included in the study and examined using echocardiography. The amplitudes of TAM and MAM were measured and the correlation between the amplitudes was calculated.

RESULTS:

In the 103 consecutive patients, a significant but relatively weak positive correlation was found between TAM and MAM amplitudes (Pearson’s correlation coefficient [r]=0.58; P<0.001). In the 19 healthy subjects, no significant correlation was found.

CONCLUSIONS:

Despite the anatomical intimacy of the annuli, the correlation between the amplitudes of TAM and MAM in consecutive patients was rather weak, and there was no correlation in healthy subjects. These findings could be due to anatomical and physiological differences between the right and left ventricles.  相似文献   
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Roughly, overdiagnosis (ODx) occurs when people are harmed by receiving diagnoses (often accompanied by interventions) that do not benefit them, usually because the diagnosed conditions do not pose a threat to their health. ODx is a theoretical as well as a practical problem as it relates to definitions of disease. Elsewhere, it has been argued that disease is a vague concept and that this vagueness may contribute to ODx. In response, we develop a stipulative or précising definition of disease, for the specific purpose of decreasing or preventing ODx. We call this diseaseODx, aimed at distinguishing cases where it would be beneficial to identify (and treat the condition) from those where diagnosis is more likely to harm than benefit. A preliminary definition of diseaseODx is that X is a diseaseODx iff there is dysfunction that has a significant risk of causing severe harm. This paper examines the 3 concepts in this definition, using a naturalistic account of function, a Feinbergian account of comparative harm, and a probabilistic understanding of risk. We then test the utility of this approach using examples of clinical conditions that are currently overdiagnosed.  相似文献   
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Objectives : To investigate rates of and reasons for second and subsequent stent procedures in an unselected, “real‐world” population. Background : Repeat stenting is the primary difference reported in clinical trials of alternative revascularization strategies. The incidence, indication, and outcome for repeat stenting in contemporary practice outside the more selective populations of trials and registries has not been described. Method : All patients undergoing a first percutaneous coronary intervention (PCI) procedure with stenting from January 2001 to August 2009 (10,509) from a large UK tertiary referral and district general hospital were identified. Mortality and the incidence, timing, and indication for repeat revascularization in this population were investigated from patient records. Results : Of 10,509 patients undergoing a first PCI and stent implant 23.5% underwent repeat angiography of which 11.2% required repeat PCI and 2% coronary artery bypass grafting (median follow‐up of 3.8 years). A total of 1.3% went on to a third PCI. The commonest indication for repeat stenting was disease progression remote from the original stent (46%) and planned staged PCI (23%); 21% had a stent‐related indication. Functional assessment before repeat stenting was used in one‐third of stable patients. Mortality was 2.5% per annum. Conclusions : In contemporary practice, patients undergoing a first stenting procedure have a low subsequent mortality, and the substantial majority (86.4%) requires no further revascularization over a median 3.8 year follow‐up. For those who do require repeat stenting, this is most commonly at a site remote from the first stent. © 2012 Wiley Periodicals, Inc.  相似文献   
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