Mehmet Ozyasar

Evaluation of left atrial mechanical functions and atrial conduction abnormalities in patients with clinical hypothyroid.

Background: The aim of this study was to investigate left atrial (LA) mechanical functions, atrial electromechanical delay and P wave dispersion in hypothyroid patients. Methods: Thirty-four patients with overt hypothyroid and thirty controls were included. A diagnosis of overt hypothyroid was reached with increased serum TSH and decreased 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 (EMD) were measured by tissue Doppler imaging (TDI). P wave dispersion was calculated by 12 lead electrocardiograms. Results: LA diameter were significantly higher in patients with overt hypothyroid (p = 0.021). LA passive emptying volume and LA passive emptying fraction were significantly decreased with hypothyroid patients (p = 0.002 and p Conclusions: This study showed that impaired LA mechanical and electromechanical function in hypothyroid patients. TSH and T4 were independent determinant of interatrial EMD and LA active emptying fraction.

Evaluation of left ventricular systolic asynchrony in patients with subclinical hypothyroidism

BACKGROUND The heart was very sensitive to fluctuating thyroid hormone levels. To assess intra-left ventricular (LV) systolic asynchrony in patients with subclinical thyroid dysfunction. METHODS Fifty patients with subclinical hypothyroidism and 40 controls were included. A diagnosis of subclinical hypothyroidism was reached with increased TSH and normal free T4. All subjects were evaluated by echocardiography. Evaluation of intra-LV systolic asynchrony was performed by tissue synchronization imaging (TSI), and four TSI parameters of systolic asynchrony were calculated. LV asynchrony was defined by these parameters. RESULTS All of the groups were similar in terms of demographic findings and conventional and Doppler echocardiograpic parameters except peak systolic velocity and early diastolic velocity. LV systolic asynchrony parameters of TSI including; standard deviation of Ts of the 12 LV segments (Ts-SD-12), maximal difference in Ts between any 2 of the 12 LV segments (Ts-12), standard deviation of TS of the 6 basal LV segments (Ts-SD-6), maximal difference in Ts between any of the 6 basal LV segments (Ts-6) were significantly lengthened in patients with subclinical hypothyroidism than controls (p <0.001, p < 0.001, p < 0.001 and p < 0.001, respectively). The prevalence of LV asynchrony was significantly higher in patients with subclinical hypothyroidism than control. CONCLUSIONS Patients with subclinical hypothyroidism present evidence of LV asynchrony by TSI. LV systolic asynchrony could be a warning sign of the early stage in cardiac systolic dysfunction in subclinical hypothyroid patients.

Detection of subclinical atrial dysfunction by two-dimensional echocardiography in patients with overt hyperthyroidism.

BACKGROUND Hyperthyroidism is an important cardiovascular risk factor in the development of atrial fibrillation and heart failure. Increased atrial electromechanical intervals are used to predict atrial fibrillation, measured by tissue Doppler imaging (TDI). AIMS To evaluate atrial electromechanical delay (EMD) and left atrial (LA) mechanical function in patients with overt hyperthyroidism. METHODS Thirty-four patients with overt hyperthyroidism and 34 controls were included. A diagnosis of overt hyperthyroidism was reached with decreased serum thyroid-stimulating hormone (TSH) and increased free T4 (fT4) concentrations. Using TDI, atrial electromechanical coupling (PA) was obtained from the lateral mitral annulus (PA lateral), septal mitral annulus (PA septum) and right ventricular tricuspid annulus (PA tricuspid). LA volumes (maximum, minimum and presystolic) were measured by the disks method in apical four-chamber view and indexed to body surface area. LA active and passive emptying volumes and fractions were calculated. RESULTS LA diameter was significantly higher in hyperthyroid patients (P=0.001). LA passive emptying volume and fraction were significantly decreased in hyperthyroid patients (P=0.038 and P<0.001). LA active emptying volume and fraction were significantly increased in hyperthyroid patients (P<0.001 and P<0.001). Left and right intra-atrial (PA lateral-PA septum and PA septum-PA tricuspid) and interatrial (PA lateral-PA tricuspid) EMDs were significantly higher in hyperthyroid patients (29.2 ± 4.4 vs 18.1 ± 2.6, P<0.001; 18.7 ± 4.3 vs 10.6 ± 2.0, P<0.001; and 10.5 ± 2.9 vs 7.1 ± 1.2, P<0.001, respectively). Stepwise linear regression analysis demonstrated that fT4 and TSH concentrations were independent predictors of interatrial EMD (β=0.436, P<0.001 and β=-0.310, P=0.005, respectively). CONCLUSION This study showed prolonged atrial electromechanical intervals and impaired LA mechanical function in patients with overt hyperthyroidism, which may be an early sign of subclinical cardiac involvement and dysrhythmias in overt hyperthyroidism.

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, Pearsons, and Spearmans 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 (β=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.

OP-210 EVALUATION OF LEFT ATRIAL MECHANICAL FUNCTIONS AND ATRIAL CONDUCTION ABNORMALITIES IN PATIENTS WITH CLINICAL HYPOTHYROID

BACKGROUND The aim of this study was to investigate left atrial (LA) mechanical functions, atrial electromechanical delay and P wave dispersion in hypothyroid patients. METHODS Thirty-four patients with overt hypothyroid and thirty controls were included. A diagnosis of overt hypothyroid was reached with increased serum TSH and decreased 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 (EMD) were measured by tissue Doppler imaging (TDI). P wave dispersion was calculated by 12 lead electrocardiograms. RESULTS LA diameter were significantly higher in patients with overt hypothyroid (p = 0.021). LA passive emptying volume and LA passive emptying fraction were significantly decreased with hypothyroid patients (p = 0.002 and p < 0.001). LA active emptying volume and LA active emptying fraction were significantly increased with hypothyroid patients (p < 0.001 and p < 0.001). Intra- and interatrial EMD, were measured significantly higher in hypothyroid patients (30.6 ± 6.1 vs 18.0 ± 2.7, p< 0.001; and 10.6 ± 3.4 vs 6.9 ± 1.4, p < 0.001, respectively). P wave dispersion were significantly higher in hypothyroid patients (48.8 ± 6.2 vs 44.3 ± 7.2, p = 0.022). In stepwise regression analysis demonstrated that, interatrial EMD and LA active emptying fraction related with TSH and fT4. CONCLUSIONS This study showed that impaired LA mechanical and electromechanical function in hypothyroid patients. TSH and T4 were independent determinant of interatrial EMD and LA active emptying fraction.