Andrea Orosz

Comparison of three-dimensional speckle tracking echocardiography and two-dimensional echocardiography for evaluation of left atrial size and function in healthy volunteers (results from the MAGYAR-Healthy study).

Noninvasive accurate assessment of left atrial (LA) size and function is an essential requirement in daily clinical practice. Real time three‐dimensional (3D) echocardiography (RT3DE) with direct volumetric method has been found to be a highly accurate and reproducible noninvasive tool for the evaluation of LA dimensions and functional properties. Three‐dimensional speckle tracking echocardiography (3DSTE) has just been introduced for volumetric assessments, which uses different, as called “block‐matching” algorithm by strain analysis. This study was designed to compare two‐dimensional (2D) echocardiography with 3DSTE for calculation of LA volumes and assessment of LA functional properties in healthy subjects.

Increased Short-Term Variability of the QT Interval in Professional Soccer Players: Possible Implications for Arrhythmia Prediction

Background Sudden cardiac death in competitive athletes is rare but it is significantly more frequent than in the normal population. The exact cause is seldom established and is mostly attributed to ventricular fibrillation. Myocardial hypertrophy and slow heart rate, both characteristic changes in top athletes in response to physical conditioning, could be associated with increased propensity for ventricular arrhythmias. We investigated conventional ECG parameters and temporal short-term beat-to-beat variability of repolarization (STVQT), a presumptive novel parameter for arrhythmia prediction, in professional soccer players. Methods Five-minute 12-lead electrocardiograms were recorded from professional soccer players (n = 76, all males, age 22.0±0.61 years) and age-matched healthy volunteers who do not participate in competitive sports (n = 76, all males, age 22.0±0.54 years). The ECGs were digitized and evaluated off-line. The temporal instability of beat-to-beat heart rate and repolarization were characterized by the calculation of short-term variability of the RR and QT intervals. Results Heart rate was significantly lower in professional soccer players at rest (61±1.2 vs. 72±1.5/min in controls). The QT interval was prolonged in players at rest (419±3.1 vs. 390±3.6 in controls, p<0.001). QTc was significantly longer in players compared to controls calculated with Fridericia and Hodges correction formulas. Importantly, STVQT was significantly higher in players both at rest and immediately after the game compared to controls (4.8±0.14 and 4.3±0.14 vs. 3.5±0.10 ms, both p<0.001, respectively). Conclusions STVQT is significantly higher in professional soccer players compared to age-matched controls, however, further studies are needed to relate this finding to increased arrhythmia propensity in this population.

Short-term beat-to-beat variability of the QT interval is increased and correlates with parameters of left ventricular hypertrophy in patients with hypertrophic cardiomyopathy

Stratification models for the prediction of sudden cardiac death (SCD) are inappropriate in patients with hypertrophic cardiomyopathy (HCM). We investigated conventional electrocardiogram (ECG) repolarization parameters and the beat-to-beat short-term QT interval variability (QT-STV), a new parameter of proarrhythmic risk, in 37 patients with HCM (21 males, average age 48 ± 15 years). Resting ECGs were recorded for 5 min and the frequency corrected QT interval (QTc), QT dispersion (QTd), beat-to-beat short-term variability of QT interval (QT-STV), and the duration of terminal part of T waves (Tpeak-Tend) were calculated. While all repolarization parameters were significantly increased in patients with HCM compared with the controls (QTc, 488 ± 61 vs. 434 ± 23 ms, p < 0.0001; QT-STV, 4.5 ± 2 vs. 3.2 ± 1 ms, p = 0.0002; Tpeak-Tend duration, 107 ± 27 vs. 91 ± 10 ms, p = 0.0015; QTd, 47 ± 17 vs. 34 ± 9 ms, p = 0.0002), QT-STV had the highest relative increase (+41%). QT-STV also showed the best correlation with indices of left ventricular (LV) hypertrophy, i.e., maximal LV wall thickness normalized for body surface area (BSA; r = 0.461, p = 0.004) or LV mass (determined by cardiac magnetic resonance imaging) normalized for BSA (r = 0.455, p = 0.015). In summary, beat-to-beat QT-STV showed the most marked increase in patients with HCM and may represent a novel marker that merits further testing for increased SCD risk in HCM.

Increased Short-Term Beat-to-Beat QT Interval Variability in Patients with Impaired Glucose Tolerance

Prediabetic states and diabetes are important risk factors for cardiovascular morbidity and mortality. Determination of short-term QT interval variability (STVQT) is a non-invasive method for assessment of proarrhythmic risk. The aim of the study was to evaluate the STVQT in patients with impaired glucose tolerance (IGT). 18 IGT patients [age: 63 ± 11 years, body mass index (BMI): 31 ± 6 kg/m2, fasting glucose: 6.0 ± 0.4 mmol/l, 120 min postload glucose: 9.0 ± 1.0 mmol/l, hemoglobin A1c (HbA1c): 5.9 ± 0.4%; mean ± SD] and 18 healthy controls (age: 56 ± 9 years, BMI: 27 ± 5 kg/m2, fasting glucose: 5.2 ± 0.4 mmol/l, 120 min postload glucose: 5.5 ± 1.3 mmol/l, HbA1c: 5.4 ± 0.3%) were enrolled into the study. ECGs were recorded, processed, and analyzed off-line. The RR and QT intervals were expressed as the average of 30 consecutive beats, the temporal instability of beat-to-beat repolarization was characterized by calculating STVQT as follows: STVQT = Σ|QTn + 1 − QTn| (30x√2)−1. Autonomic function was assessed by means of standard cardiovascular reflex tests. There were no differences between IGT and control groups in QT (411 ± 43 vs 402 ± 39 ms) and QTc (431 ± 25 vs 424 ± 19 ms) intervals or QT dispersion (44 ± 13 vs 42 ± 17 ms). However, STVQT was significantly higher in IGT patients (5.0 ± 0.7 vs 3.7 ± 0.7, P < 0.0001). The elevated temporal STVQT in patients with IGT may be an early indicator of increased instability of cardiac repolarization during prediabetic conditions.

Left atrial ejection force correlates with left atrial strain and volume-based functional properties as assessed by three-dimensional speckle tracking echocardiography (from the MAGYAR-Healthy Study)

INTRODUCTION AND OBJECTIVE Three-dimensional (3D) speckle tracking echocardiography (3DSTE) is a novel method for assessment of left atrial (LA) volumes and function without geometrical assumptions. 3DSTE allows detailed assessment of LA features including volume measurements, strain assessments and calculation of LA ejection force (LAEF). LA strain and volume-based functional parameters originate from the same 3D dataset, but assessment of LAEF requires more data including measurement of mitral annular dimensions and Doppler-derived inflow velocities. The present study was designed to find correlations between LAEF and 3DSTE-derived LA volume-based functional properties and strain parameters in healthy subjects. METHODS The study population comprised 34 randomly selected healthy subjects (age 36.1±11.2 years, 15 men) in sinus rhythm, all of whom had undergone standard two-dimensional transthoracic Doppler echocardiographic study extended with 3DSTE. RESULTS Mitral annulus diameter-based LAEF correlated with global LA peak circumferential (r=0.39, p=0.02), longitudinal (r=0.32, p=0.05) and area (r=0.43, p=0.01) strain, total atrial stroke volume (r=0.30, p=0.05) and total atrial emptying fraction (r=0.31, p=0.05) characterizing (systolic) LA reservoir function and global LA 3D strain at atrial contraction (r=-0.44, p=0.01) and active atrial emptying fraction (r=0.36, p=0.04) characterizing (diastolic) LA contraction function (booster pump phase). CONCLUSIONS Complex LA functional assessment can be provided by 3DSTE, including calculation of LAEF and volume-based and strain functional properties, with significant correlations between these parameters.

Complex evaluation of left atrial dysfunction in patients with type 1 diabetes mellitus by three-dimensional speckle tracking echocardiography: Results from the MAGYAR-path study

Objective: Changes in left atrial (LA) function can be observed in type 1 diabetes mellitus (T1DM). Three-dimensional (3-D) speckle tracking echocardiography (STE) seems to be a promising tool for volumetric and functional evaluation of LA. The objective of the present study was to compare 3DSTE-derived LA volumetric and strain parameters between T1DM patients and matched healthy controls. Methods: This prospective study consists of 17 subcutaneous insulin pump-treated non-obese patients with T1DM (mean age: 33.5±8.2 years, 8 males). To exclude possible cardiovascular disease, patients with complaints of chest pain, dyspnea, or signs of cerebrovascular disease or peripheral artery disease were not included. Their results were compared with 20 age-matched and gender-matched healthy controls (mean age: 36.9±11.0 years, 9 males). Independent sample Student t-test and Fisher’s exact test were used for comparisons. Bland–Altman method was used for evaluating intraobserver and interobserver correlations. Results: Anemia and impaired renal function were not confirmed in T1DM patients. Calculated LA maximum and minimum volumes and LA volume before atrial contraction were significantly increased in T1DM patients. Total atrial stroke volume was increased (23.6±6.9 mL vs. 19.6±4.6 mL, p=0.04), whereas mean segmental circumferential peak strain was decreased (28.9%±11.4% vs. 37.3%±12.5%, p=0.04). Segmental basal longitudinal and area strains were increased, whereas segmental superior circumferential and area strains and midatrial 3-D strain were decreased in T1DM. Conclusion: Both 3DSTE-derived volumetric and strain analysis confirmed alterations in LA function, suggesting early LA remodeling in patients with T1DM. (Anatol J Cardiol 2016; 16: 587-93)

Increased short-term beat-to-beat variability of QT interval in patients with acromegaly

Cardiovascular diseases, including ventricular arrhythmias are responsible for increased mortality in patients with acromegaly. Acromegaly may cause repolarization abnormalities such as QT prolongation and impairment of repolarization reserve enhancing liability to arrhythmia. The aim of this study was to determine the short-term beat-to-beat QT variability in patients with acromegaly. Thirty acromegalic patients (23 women and 7 men, mean age±SD: 55.7±10.4 years) were compared with age- and sex-matched volunteers (mean age 51.3±7.6 years). Cardiac repolarization parameters including frequency corrected QT interval, PQ and QRS intervals, duration of terminal part of T waves (Tpeak-Tend) and short-term variability of QT interval were evaluated. All acromegalic patients and controls underwent transthoracic echocardiographic examination. Autonomic function was assessed by means of five standard cardiovascular reflex tests. Comparison of the two groups revealed no significant differences in the conventional ECG parameters of repolarization (QT: 401.1±30.6 ms vs 389.3±16.5 ms, corrected QT interval: 430.1±18.6 ms vs 425.6±17.3 ms, QT dispersion: 38.2±13.2 ms vs 36.6±10.2 ms; acromegaly vs control, respectively). However, short-term beat-to-beat QT variability was significantly increased in acromegalic patients (4.23±1.03 ms vs 3.02±0.80, P<0.0001). There were significant differences between the two groups in the echocardiographic dimensions (left ventricular end diastolic diameter: 52.6±5.4 mm vs 48.0±3.9 mm, left ventricular end systolic diameter: 32.3±5.2 mm vs 29.1±4.4 mm, interventricular septum: 11.1±2.2 mm vs 8.8±0.7 mm, posterior wall of left ventricle: 10.8±1.4 mm vs 8.9±0.7 mm, P<0.05, respectively). Short-term beat-to-beat QT variability was elevated in patients with acromegaly in spite of unchanged conventional parameters of ventricular repolarization. This enhanced temporal QT variability may be an early indicator of increased liability to arrhythmia.

A mitralis anulus es a bal pitvar funkcioja kozotti osszefuggesek vizsgalata haromdimenzios speckle-tracking echokardiografia segitsegevel egeszseges onkentesekben : eredmenyek a MAGYAR-Healthy Tanulmanybol

INTRODUCTION Left atrium is a heart chamber with dinamic motion communicating with left ventricle through the mitral valve and its annulus. AIM The aim of the present study was to analyse whether relationships could exist between three-dimensional speckle-tracking echocardiography-derived morphologic and functional parameters of the left atrium and mitral annulus in healthy subjects. METHOD The present study comprised 35 healthy volunteers. Maximum (Vmax) and minimum (Vmin) left atrial volumes and left atrial volume before atrial contraction (VpreA) were measured, and several functional parameters based on these volumes were calculated in all cases. Morphologic and functional characteristics of the mitral annulus were also determined. RESULTS While Vmax showed correlations with both systolic and diastolic mitral annulus parameters, Vmin-VpreA correlated with only systolic ones. While total left atrial stroke volume correlated with both systolic and diastolic mitral annular parameters, passive left atrial stroke volume showed correlations only with diastolic ones. CONCLUSIONS Correlations exist between left atrial and mitral annular morphological and functional characteristics in healthy subjects.

Cardiovascular autonomic neuropathy and glucose variability in patients with type 1 diabetes: Is there an association?

Introduction The oxidative stress associated with glucose variability might be responsible for neuronal damage while autonomic neuropathy (AN) has a detrimental effect on metabolism. The aim of the study was to find relationship between AN and GV in type 1 diabetic patients and to identify further factors that affect GV. Patients and methods Twenty type 1 diabetic patients were involved (age: 39.5 ± 3.4 years, duration of diabetes: 17.5 ± 2.5 years; HbA1c: 8.1 ± 0.2%, mean ± SE). AN was assessed by the cardiovascular reflex tests. The interstitial glucose levels were determined following insertion of a subcutaneous electrode during the continuous glucose monitoring (CGM) method on six consecutive days. GV was characterized by calculation of four parameters. Results SD of interstitial glucose values correlated positively with the overall AN score and the degree of the orthostatic reduction of systolic blood pressure (AN-score-SD ρ = 0.47, p < 0.05; orthostasis-SD: ρ = 0.51, p < 0.05). Mean absolute glucose (MAG) correlated with three parameters of AN (AN-score-MAG: ρ = 0.62, p < 0.01; 30/15 ratio-MAG: ρ = −0.50, p < 0.05; orthostasis-MAG: ρ = 0.59, p < 0.01). The HbA1c also correlated with two parameters of GV (HbA1c-continuous overlapping net glycemic action: ρ = 0.56, p < 0.05; HbA1c-MAG: ρ = 0.45, p < 0.05). The frequency of hypoglycemia did not exhibit any correlation with measures of GV. Conclusion Severity of glucose variability but not overall glucose load correlates with both parasympathetic and sympathetic dysfunctions in type 1 diabetes. Higher HbA1c is associated with more severe glucose variability. The observed correlation between increased glucose variability and the severity of AN necessitates the further exploration of this relationship.

Changes in mitral annular morphology and function in young patients with type 1 diabetes mellitus—results from the three-dimensional speckle tracking echocardiographic MAGYAR-Path Study

BACKGROUND Alterations in mitral annular size and function could be demonstrated in cardiomyopathies and ischaemic heart disease. The present study was designed to evaluate mitral annulus (MA) morphology and function in young type 1 diabetes mellitus (T1DM) patients by three-dimensional speckle tracking echocardiography (3DSTE) and to compare their results to matched healthy controls. METHODS The study comprised 18 patients with T1DM (mean age: 33.0±8.0 years). Their results were compared to that of 20 age- and gender-matched healthy controls (mean age: 37.8±10.9 years). Complete two-dimensional (2D) Doppler echocardiography and 3DSTE have been performed in all cases. RESULTS No significant differences could be demonstrated in demographic and standard echocardiographic parameters between the groups. Significantly enlarged diastolic MA diameter (2.87±0.27 mm vs. 2.58±0.32 mm, P=0.01), MA diameter index 1.61±0.20 cm/m(2) vs. 1.30±0.39 cm/m(2), P=0.008, and MA area index (4.81±0.88 cm(2)/m(2) vs. 3.91±1.35 cm(2)/m(2), P=0.03) could be demonstrated in T1DM together with augmented MA fractional shortening (28.64±9.63% vs. 20.35±12.50%, P=0.05). CONCLUSIONS Early alterations in MA size and function could be demonstrated in young patients with T1DM by 3DSTE.