ABSTRACT
Cardiac resynchronization therapy [CRT] has been introduced as a promising therapeutic choice in heart failure [HF] patients with ventricular dyssynchrony, shown with a wide QRS. In previous study, we showed a positive effect of CRT on ejection fraction. This study aimed to evaluate the effect of CRT on the severity of mitral regurgitation [MR] quantitatively using the volumetric Doppler method in HF patients. In this prospective before-after survey, 22 HF patients with wide QRS [>/=120 ms] and NYHA class III who were included. All patients were evaluated initially for QRS width, NYHA class, MR volume, MR fraction and mitral valve area [MV area]. Biventricular pacing was done through cardiac-resynchronization device along with three pacing leads and same evaluations were done after CRT. The mean [SD] QRS width and NYHA class were significantly decreased after CRT in HF patients [p<0.001]. Also MR volume [46.9 +/- 30.2 mL vs. 27.0 +/- 26.4 mL, p<0.001] and fraction [40.1 +/- 25.5% vs. 26.8 +/- 22.7%, p=0.002] were improved following CRT. The decrease of MV area after CRT was also significant [10.6 +/- 3.0 cm[2] vs. 8.6 +/- 2.6 cm[2], p<0.001]. As MR is associated with morbidity and mortality in HF patients and the standard surgical therapy may not be practical for a majority of them, this novel treatment may improve their disease condition significantly
ABSTRACT
QT interval parameters have been suggested as a predictor of lethal arrhythmia and mortality in patients with myocardial infarction. The aim of the present study was to compare the value of QT interval indices in patients presenting with non-ST-segment elevation myocardial infarction [NSTEMI] between a group of patients with type 2 diabetes mellitus and a nondiabetic group of patients. This case-control study evaluated QT interval parameters in 115 patients [47 diabetic and 68 nondiabetic patients] diagnosed with NSTEMI between September 2011 and July 2012. The following QT interval indices were analyzed: maximum [max] and minimum [min] QT interval; max and min corrected QT interval [QTc]; QT dispersion [QTd]; and corrected QT dispersion [QTcd]. All the patients were observed for ventricular arrhythmia during their hospital course and underwent coronary angiography. They were selected to undergo coronary artery bypass surgery [CABG] or percutaneous coronary angioplasty [PCI] based on their coronary anatomy. The mean age of the patients was 60.8 +/- 11.4 years. The patients were 40.0% female and 60.0% male. There were no significant differences in clinical characters between type 2 diabetic and nondiabetic patients with NSTEMI. Compared with post-myocardial infarction patients without diabetes, those with type 2 diabetes had higher QTc max, QTd and QTcd [p value < 0.05]. There was a significant difference in QTd and QTcd in the patients needing coronary revascularization with diabetes as opposed to the nondiabetics [p value = 0.035 and p value = 0.025, respectively] as well as those who had ventricular arrhythmia with diabetes [p value = 0.018 and p value = 0.003, respectively]. QTcd was higher in the patients who had higher in-hospital mortality [p value = 0.047]. The QTc max, QTd and QTcd were significantly [all p values < 0.05] associated with ventricular arrhythmia, QTcd with need for revascularization and QTc max with in-hospital mortality in the diabetic patients. Based on the findings of this study, it seems that type 2 diabetics with NSTEMI have greater QTc max, QTd, and QTcd and these QT parameters may have a relationship with worse cardiac outcomes and poorer prognoses
ABSTRACT
Cardiac resynchronization therapy [CRT] has introduced as new treatment strategy in heart failure [HF] patients and some of its effects have been investigated. The aim of this study was to study the effectiveness of CRT in the improvement of left ventricular systolic function indicated by left ventricular ejection fraction [LVEF] in HF patients. In our prospective study 22 HF patients with NYHA class III and above, QRS duration>120 ms and EF [ejection fraction]
ABSTRACT
The signal-averaged electrocardiograph is a noninvasive method to evaluate the presence of the potentials generated by tissues activated later than their usual timing in the cardiac cycle. The purpose of this study was to demonstrate the correlation between the filtered QRS duration obtained via the signal-averaged electrocardiography and left ventricular dimensions and volumes and then to compare it with the standard electrocardiography. We included patients with advanced systolic left ventricular dysfunction [ejection fraction