Increased QT interval and QT dispersion have been associated with higher mortality in population-based studies and in patients with myocardial infarction. However, the prognostic significance of these measurements in patients with left ventricular (LV) systolic dysfunction is not clear. Rate corrected QT interval (QTc) and QT dispersion (QTd) were measured by means of an automated method from digitized echocardiograms in 2265 patients with an LV ejection fraction < or =40% and were related to survival. Increased QTc was strongly related to mortality in the whole group and in subsets on the basis of age and the level of LV systolic dysfunction. There was a graded increase in mortality rate with an increase in QTc. The effect of QTc on mortality was incremental to the effects of age and ejection fraction. QT interval was measurable in > or =6 leads in 1193 patients in whom QTd was computed. QTd higher than the mean value of 35 ms was associated with an increase in all cause mortality (P =.04). Its mortality impact was most pronounced in the older patients, patients with more severe LV dysfunction, and patients with increased QTc. Both QTc prolongation and increased QTd are associated with higher mortality rate in patients with moderate and severe LV dysfunction.

Current thought regarding the progression of calcific aortic stenosis (AS) is presented. After summarizing contemporary ideas about AS pathogenesis, the present article examines the factors that may affect disease progression. Data indicate that this process may be accelerated by aortic valve structure, degree of valvular calcification, chronic renal insufficiency and cardiovascular risk factors such as diabetes and dyslipidemia. Finally, the present review discusses potential therapeutic targets to slow AS progression.

Background— Mitral regurgitation (MR) is common in those with severe aortic regurgitation (AR) and can predispose to atrial fibrillation, heart failure, and a need for mitral valve surgery during aortic valve replacement (AVR). However, little data exist as to its clinical and prognostic implications. Methods and Results— Search of our echocardiographic data base between 1993 and 2007 yielded 756 patients with severe AR. with comprehensive clinical data from chart review and mortality data from National Death Index. Mortality was analyzed as a function of MR severity. Effect of AVR and concomitant mitral valve repair were investigated. Patient characteristics were age, 61±17 years; female sex, 41%; and ejection fraction, 54±19%. MR grade ≥2+ was present in 343 (45%) patients: 2+ in 152 (20%), 3+ in 93 (12%), and 4+ in 98 (13%). There was a progressive decrease in survival with each grade of MR ( P <0.0001). Performance of AVR was associated with a better survival in those with 3 or 4+ MR ( P =0.02). In addition, concomitant mitral valve repair in these patients resulted in a better survival (hazard ratio, 0.29; P =0.02). Conclusions— MR is common in patients with severe AR, with 3 or 4+ MR occurring in a quarter of these patients. It is an independent predictor of reduced survival. Performance of AVR and concomitant mitral valve repair is associated with a better survival. Development of MR should serve as an indication for AVR even in asymptomatic patients.