The relationship between exercise capacity and masked hypertension in sedentary patients with diabetes mellitus.

AIM: Although exaggerated blood pressure responses (EBPR) to exercise have been related to future hypertension and masked hypertension (MHT), the relationship between exercise capacity and MHT remains unclear. A sedentary life style has been related to increased cardiovascular mortality, diabetes mellitus (DM), and hypertension. In this study, we aimed to examine the relationship between exercise capacity and MHT in sedentary patients with DM. METHODS: This study included 85 sedentary and normotensive patients with DM. Each patient's daily physical activity level was assessed according to the INTERHEART study. All patients underwent an exercise treadmill test, and exercise duration and capacity were recorded. Blood pressure (BP) was recorded during all exercise stages and BP values ≥ 200/110 mmHg were accepted as EBPR. MHT was diagnosed in patients having an office BP <140/90 mmHg and a daytime ambulatory BP >135/85 mmHg. Patients were divided into two groups according to their ambulatory BP monitoring (MHT and normotensive group). RESULTS: The prevalence of MHT was 28.2%. Exercise duration and capacity were lower in the MHT group than in the normotensive group (p<0.05) and were negatively correlated with age, HbA1c, mean daytime BP, and mean 24 hour BP. Peak exercise systolic BP and the frequency of EBPR were both increased in the MHT group (25.0% and 8.1%, respectively, p=0.03). According to a multivariate regression, exercise capacity (OR: 0.61, CI95%: 0.39-0.95, p=0.03), EBPR (OR: 9.45, CI95%: 1.72-16.90, p=0.01), and the duration of DM (OR: 0.84, CI95%: 0.71-0.96, p=0.03) were predictors of MHT. CONCLUSION: Exercise capacity, EBPR, and the duration of DM were predictors of MHT in sedentary subjects with DM.

Predictive value of total atrial conduction time measured with tissue Doppler imaging for postoperative atrial fibrillation after coronary artery bypass surgery.

OBJECTIVE: Postoperative atrial fibrillation (POAF) complicating coronary artery bypass grafting surgery (CABG) increases morbidity and stroke risk. Total atrial conduction time (PA-TDI duration) has been identified as an independent predictor of new-onset atrial fibrillation (AF). We aimed to assess whether PA-TDI duration is a predictor of AF after CABG. METHODS: In 128 patients who had undergone CABG, preoperative clinical and echocardiographic data were compared between patients with and without POAF. The PA-TDI duration was assessed by measuring the time interval between the beginning of the P wave on the surface ECG and point of the peak A wave on TDI from left atrium (LA) lateral wall just over the mitral annulus. RESULTS: Patients with POAF (38/128, 29.6 %) were older (68.1 ± 11.1 vs. 59.3 ± 10.2 years; p < 0.001), had higher LA maximum volume, had prolonged PA-TDI duration, and had lower ejection fraction compared with patients without POAF. PA-TDI duration was found to be significantly increased in POAF group (134.3 ± 19.7 vs. 112.5 ± 17.7 ms; p = 0.01). On multivariate analysis, age (95 % CI = 1.03-1.09; p = 0.003), LA maximum volume (95 % CI = 1.01-1.06; p = 0.03), and prolonged PA-TDI duration (95 % CI, 1.02-1.05; p = 0.001) were found to be the independent risk factors of POAF. CONCLUSIONS: In this study, LA maximum volume and PA-TDI duration were found to be the independent predictors of the development of POAF after CABG. Echocardiographic predictors of left atrial electromechanical dysfunction may be useful in risk stratifying of patients in terms of POAF development after CABG.

Coronary artery ectasia is associated with atrial electrical and mechanical dysfunction: an observational study.

OBJECTIVE: The aim of our study was to investigate total atrial conduction time and left atrial (LA) mechanical function in patients with isolated coronary artery ectasia (ICAE). METHODS: Sixty patients with ICAE without any visible coronary stenosis were enrolled to this cross-sectional observational study. The control group consisted of 40 age- and gender-matched patients. Left atrial mechanical functions were measured by the method of discs in the apical-four chamber echocardiographic view. LA mechanical function parameters were calculated. P wave dispersion was measured on electrocardiography (ECG). The total atrial conduction time (PA-tissue Doppler imaging (TDI) duration) was assessed by measuring the time interval between the beginning of the P wave on the surface ECG and point of the peak A wave on TDI from LA lateral wall just over the mitral annulus. Student t, Mann-Whitney U, Pearson's, and Spearman's correlation analysis and multiple regression analysis were used for statistical analysis. RESULTS: The clinical and laboratory characteristics were similar in two groups. Both groups were similar in terms of Vmax and LA total emptying volume (29.0 ± 7.3 vs. 31.9 ± 6.5 mL/m², p=0.082 and 19.9 ± 5.1 vs. 20.0 ± 5.2 mL/m², p=0.821). However, LA passive emptying volume and LA passive emptying fraction were significantly decreased with ICAE patients (11.1 ± 3.2 vs. 13.5 ± 3.8 ml/m², p=0.005 and 35.2 ± 7.2 vs. 47.8 ± 9.4 mL/m², p<0.001). But LA active emptying volume and LA active emptying fraction were significantly increased in ICAE patients (9.1 ± 2.6 vs. 6.4 ± 3.0 mL/m², p<0.001 and 45.3 ± 8.1 vs. 40.7 ± 6.7 mL/m², p=0.002). PA-TDI duration was measured significantly higher in patients with ICAE than control group (131.8 ± 5.7 vs. 114.4 ± 9.1 ms, p<0.001). Multiple linear regression analyses showed that ectatic segment number was an independent factor of PA-TDI duration (ß=0.581, 95% CI=4.046-6.295, p<0.001). CONCLUSION: Our study demonstrated presence of LA electrical and mechanical dysfunction in patients with ICAE. LA dysfunction may be associated with cardiac pathologies as arrhythmias, decrease in cardiac output and congestive failure.

Evaulation of atrial conduction abnormalities and left atrial mechanical functions in patients with subclinical thyroid disorders.

INTRODUCTION: Changes of thyroid hormones levels may lead to effects, not only in ventricular function, but also atrial function. The aim of this study was to investigate left atrial (LA) mechanical functions, atrial electromechanical coupling and P wave dispersion in patients with subclinical thyroid disorders. MATERIAL AND METHODS: Eighty patients with subclinical thyroid disorders and forty controls were included. A diagnosis of subclinical thyroid disorders were reached with increased or decreased serum TSH and normal free T4 (fT4) levels. LA volumes were measured using the biplane area length method and LA active and passive emptying volumes and fraction were calculated. Intra- and interatrial electromechanical delay were measured by tissue Doppler imaging (TDI). RESULTS: All groups had similar demographic findings. LA mechanical functions significantly impaired in subclinical thyroid disorders than control group. Intra- and Interatrial delay, were measured significantly higher in patients with subclinical thyroid disorders than control group. PA lateral and interatrial delay were positively correlated with TSH (r = 0.507, p = 0.006 and r = 0.455, p = 0.015, respectively) in subclinical hypothyroid patients. There was negative correlation between TSH and interatrial delay (r = -0.492, p = 0.006) in subclinical hyperthyroid patients. Linear multivariate regression analysis demonstrated that, TSH was the only an independent factor of interatrial delay in patients with subclinical thyroid disorders. CONCLUSIONS: This study showed that impaired LA mechanical and electromechanical function in subclinical thyroid disorders. TSH was an independent determinant of interatrial delay. Prolonged atrial electromechanical coupling time and impaired mechanical atrial functions may be related to the increased incidence of arrhythmias.

[The effect of nondipper blood pressure pattern on target organ damage in patients with metabolic syndrome]. / Metabolik sendromlu hastalarda nondipper kan basinci seyrinin hedef organ hasari üzerine etkisi.

OBJECTIVES: Both metabolic syndrome (MetS) and nondipping status (insufficient reduction in nocturnal blood pressure) have been linked with target organ damage. We evaluated the effect of nondipping status on target organ damage in subjects with MetS. STUDY DESIGN: Eighty-two patients diagnosed as having MetS were divided into two groups according to the findings of 24-hour ambulatory blood pressure monitoring as dipper (n=35, 19 women, 16 men; mean age 48.4+/-6.4 years) and nondipper (n=47, 35 women, 12 men; mean age 50.4+/-4.7 years). Cardiac damage was assessed by conventional and tissue Doppler echocardiography, and renal damage by 24-hour urinary albumin excretion. RESULTS: The two groups were similar with regard to age, body mass index, presence of diabetes, smoking, clinical and 24-hour, daytime and nighttime blood pressures, plasma lipid profile, distribution of and the mean total number of MetS criteria. The ratio of early (Em) to late (Am) left ventricular peak diastolic myocardial velocities (Em/Am) was significantly lower in nondippers (p=0.016). Nondippers also had higher values of left ventricular mass index, myocardial performance index, and 24-hour urinary albumin excretion, but these differences did not reach a significant level (p=0.110, p=0.099, p=0.093, respectively). Multivariate regression analysis showed increasing age and nondipping status as independent factors associated with decreased Em/Am ratio (beta=-0.25, p=0.020 and beta=-0.22, p=0.042, respectively). CONCLUSION: In subjects with MetS, nondipping status may be associated with both cardiac and renal damage independent of other components of MetS. Since the degree of diastolic dysfunction is more marked than that of albuminuria in nondippers, it may be extrapolated that the extent of cardiac damage surpasses renal damage in these subjects.