BACKGROUND/AIMS: The aim of this study was to investigate atrial conduction times and left atrial mechanical functions, the noninvasive predictors of atrial fibrillation, in prediabetic patients with impaired fasting glucose (IFG) and impaired glucose tolerance (IGT). METHODS: Study included 59 patients (23 males, 36 females; mean age 52.5 ± 10.6 years) diagnosed with IFG or IGT by the American Diabetes Association criteria, and 43 healthy adults (22 males, 21 females; mean age 48.5 ± 12.1 years). Conventional and tissue Doppler echocardiography were performed. The electromechanical delay parameters were measured from the onset of the P wave on the surface electrocardiogram to the onset of the atrial systolic wave on tissue Doppler imaging from septum, lateral, and right ventricular annuli. The left atrial volumes were calculated by the disk method. Left atrial mechanical functions were calculated. RESULTS: The mitral E/A and E′/A′ ratios measured from the lateral and septal annuli were significantly lower in the prediabetics compared to the controls. The interatrial and left atrial electromechanical delay were significantly longer in prediabetic group compared to the controls. Left atrial active emptying volume (LAAEV) and fraction (LAAEF) were significantly higher in the prediabetics than the controls. LAAEV and LAAEF were significantly correlated with E/A, lateral and septal E′/A′. CONCLUSIONS: In the prediabetic patients, the atrial conduction times and P wave dispersion on surface electrocardiographic were longer before the development of overt diabetes. In addition, the left atrial mechanical functions were impaired secondary to a deterioration in the diastolic functions in the prediabetic patients.
Adult ; Atrial Fibrillation ; Echocardiography, Doppler ; Electrocardiography ; Fasting ; Female ; Glucose ; Humans ; Male ; Methods ; Prediabetic State

BACKGROUNDObstructive sleep apnea syndrome (OSAS) is a disease with increasing prevalence, which is mainly characterized by increased cardiopulmonary mortality and morbidity. It is well-known that OSAS patients have increased prevalence of cardiovascular diseases including coronary heart disease, heart failure, and arrhythmias. The aim of this study was to evaluate the presence of prolonged and fragmented QRS complexes, which have previously been associated with cardiovascular mortality, in OSAS patients.

METHODSOur study included 51 patients (mean age 41.6 ± 10.1 years) who were recently diagnosed with OSAS (apnea-hypopnea index [AHI] ≥5 events/h) and never received therapy. The control group consisted of 34 volunteers (mean age 43.1 ± 11.6 years) in whom OSAS was excluded (AHI <5 events/h). The longest QRS complexes was measured in the 12-lead electrocardiogram (ECG) and the presence of fragmentation in QRS complexes was investigated.

RESULTSFragmented QRS frequency was significantly higher in patients with OSAS (n = 31 [61%] vs. n = 12 [35%], P = 0.021). QRS and QTc durations were also significantly longer in OSAS patients than controls (99.8 ± 13.9 ms vs. 84.7 ± 14.3 ms, P < 0.001; 411.4 ± 26.9 ms vs. 390.1 ± 32.2 ms, P = 0.001, respectively). Analysis of the patient and controls groups combined revealed a weak-moderate correlation between AHI and QRS duration (r = 0.292, P = 0.070). OSAS group had no correlation between AHI and QRS duration (r = -0.231, P = 0.203).

CONCLUSIONSIn our study fragmented QRS frequency and QRS duration were found to increase in OSAS patients. Both parameters are related with increased cardiovascular mortality. Considering the prognostic importance of ECG parameters, it may be reasonable to recommend more detailed evaluation of OSAS patients with fragmented or prolonged QRS complexes with respect to presence of cardiovascular diseases.

Adult ; Case-Control Studies ; Echoencephalography ; Electrocardiography ; Female ; Humans ; Male ; Polysomnography ; Sleep Apnea, Obstructive ; physiopathology