[A. N. Bakoulev Scientific Center for Cardiovascular Surgery].

OBJECTIVE: to assess dynamics of diastolic function for detection of development of diastolic dysfunction (DD) and it's causes, to evaluate the effect of DD on prognosis in the postoperative period in patients with acquired heart diseases. MATERIALS AND METHODS: We included in this study 112 patients with aortic and mitral valve diseases (90 men, 22 women, median age 51 [35; 57] years). All patients underwent echocardiography (echo), tissue Doppler, speckle tracking echo prior to surgery, in the early postoperative period (8-14 days) and in 12-36 months after surgery. In 28 patients dynamic contrast-enhanced magnetic resonance imaging was also performed. Patients were divided into groups according to prognosis: group 0 - without complications; group 1 - with postoperative heart failure (HF) and preserved left ventricular ejection fraction (EF); group 2 - with HF and EF <45 %. The following parameters were used for identifying left ventricular (LV) DD: septal velocity es <7 cm / sec, lateral el <10 cm / sec, average E / e ratio >14, left atrial (LA) volume index >34 ml / m2, peak tricuspid regurgitation velocity >2.8 m / sec. RESULTS: Initially diastolicLV function was normal in 34 of 112 patients (30.4 %), in early postoperative period DD emerged in 9 (26.5 %) of these patients. The appearance of LV DD was associated with decrease of septal es immediately after surgery and its subsequent progressive decline in the long-term postoperative period from 8.5±0.71 to 4.6 ±0.53 cm / sec (p=0.005). Worsening of diastolic function and lowering of septal velocity was detected namely in patients with presence of fibrosis. In the group of other patients in whom fibrosis was not studied and the degree of DD increased there was a transient decrease of lateral el (from 10.2±3.1 to 7.5±2.43 cm / sec, p=0.035) and an increase of the E / el (from 10.53±4.07 to 14.5±5.23, p=0.05) in the early period after the operation. There were no correlations between DD and LV EF,LV volumes, and development of arrhythmias. The prognostic model for DD included average longitudinal deformation of LA (global LA longitudinal strain) and E / e ratio on the tricuspid lateral annular velocity. CONCLUSIONS: Appearance of DD in postoperative period after correction of acquired heart defects was due to damage of the septal diastolic function which correlated with fibrosis and was indicative of inadequate myocardial protection. The model of development of heart failure with normal EF after operation was designed.

[Opportunities Provided by Stress Echocardiography and Stress Speckle tracking for the Evaluation of Myocardial Reserve Among Patients With Heart Defects].

Heart failure risk factors research as well as studies of myocardial dysfunction to identify subclinical heart disease are important problems that can be solved with stress echocardiography and new methods of myocardial function analysis. Key factors defining the prognosis of patients with valvular diseases are heart remodeling and myocardial contractility. Heart remodeling types have been studied in detail by the present time. Elucidation of capability of stress echocardiography to detect asymptomatic dysfunction and assess prognosis of the results of surgery is continuing. Most important technological achievements of the last ten years gave us the opportunity to quantitatively assess myocardial function and movement. Tissue Doppler and Speckle Tracking enabled us to find alternative to invasive methods way to determination of parameters of global and regional myocardial function. Nowadays the first research results on the use of Speckle Tracking to estimate the contractile reserve are appearing. A high prognostic significance of global longitudinal deformation has been revealed. The aim of this article is to summarize available data on assessment of severity of valvular heart disease and the state of myocardial contractile reserve using stress echocardiography, Tissue Doppler and Speckle tracking data.

Experimental Study of Kinematic Activity of Left Ventricular Myocardium.

A method of invasive and non-invasive examination of epicardial motion was tested on domestic pigs (n=15). The invasive study employed a contact kinematic sensor of the epicardial wall motion, which determined the amplitude, velocity, and angular parameters of examined epicardial region. A non-invasive assessment of the epicardial kinematics based on echocardiographic 2D Velocity Vector Imaging and ECG recoding used to determine the heart electrical axis. The 4-chamber views were uses to analyze the longitudinal displacements of lateral wall of the left ventricle at the basal, mid, and apical segments. In addition, the radial displacements were determined in short axis projections at basal and apical segments as well as at the level of papillary muscles. The animals with normal or horizontal heart's electrical axis demonstrated similar displacement of the epicardium along X-axis and in longitudinal direction, while displacement along Y-axis corresponded to that in radial direction. The combined invasive and non-invasive approach in measurement of epicardium motion makes it possible to quantify the kinematic epicardial activity.

[The use of novel technologies for assessment of myocardial function in clinical practice].

Key factors defining the prognosis of patients with heart failure (HF) are cardiac remodeling and myocardial contractility. New methods of visualization of myocardial motion gave impulse to research in the area of heart physiology and pathology. However in clinical practice these methods are still rarely used. Evaluation of systolic and diastolic functions based on tissue Doppler (TD), 2D and 3D speckle tracking data provides information on the pressure of left ventricular (LV) filling and enables carrying out differential diagnosis between constrictive pericarditis and myocardial diseases with diastolic dysfunction, dyspnea caused by cardiac and extracardiac causes. It also helps to understand physiology of systolic and diastolic dysfunction, impairment of LV pump function. It also enables monitoring response to HF treatment. Myocardial function analysis gives an opportunity to carry out early diagnostics, to detect subclinical LV dysfunction, to detect dyssynchrony and to predict response to resynchronising therapy. In this article we sum up indicators of systolic and diastolic dysfunction in various types of pathology and present assessment of mechanical dyssynchrony with the aid of TD, 2D and 3D speckle tracking. It is stressed that these methods allow carrying out quantitative analysis of myocardial motion. Practically all analyzed parameters are nonspecific and similar to parameters of remodeling change unidirectionally irrespective of pathology. The aim of this article is to summarize available data and knowledge on the determination of myocardial function. This is important for clinical practice and understanding of future development of the above methods.

[The Use of Novel Technologies for Assessment of Myocardial Function in Clinical Practice].

Key factors defining the prognosis of patients with heart failure (HF) are cardiac remodeling and myocardial contractility. New methods of visualization of myocardial motion gave impulse to research in the area of heart physiology and pathology. However in clinical practice these methods are still rarely used. Evaluation of systolic and diastolic functions based on tissue Doppler (TD), 2D and 3D speckle tracking data provides information on the pressure of left ventricular (LV) filling and enables carrying out differential diagnosis between constrictive pericarditis and myocardial diseases with diastolic dysfunction, dyspnea caused by cardiac and extracardiac causes. It also helps to understand physiology of systolic and diastolic dysfunction, impairment of LV pump function. It also enables monitoring response to HF treatment. Myocardial function analysis gives an opportunity to carry out early diagnostics, to detect subclinical LV dysfunction, to detect dyssynchrony and to predict response to resynchronising therapy. In this article we sum up indicators of systolic and diastolic dysfunction in various types of pathology and present assessment of mechanical dyssynchrony with the aid of TD, 2D and 3D speckle tracking. It is stressed that these methods allow carrying out quantitative analysis of myocardial motion. Practically all analyzed parameters are nonspecific and similar to parameters of remodeling change unidirectionally irrespective of pathology. The aim of this article is to summarize available data and knowledge on the determination of myocardial function. This is important for clinical practice and understanding of future development of the above methods.

[The assessment of mechanical heart valves stenosis in adults after aortic valve replacement: the advantage of full-flow design of mechanical valve].

The analysis of transprosthetic hemodynamics in adults after aortic valve replacement in the Bakoulev Center for Cardiovascular Surgery in 2007-2010 demonstrated the hemodynamic advantage of the concept of new full-flow mechanical aortic valve prosthesis "CorBeat". Having the same size of internal orifice and tissue annulus diameters, the values of transprosthetic parameters (peak and mean gradients, blood flow velocities) through "CorBeat" were close to physiological values of transvalvular native aortic parameters and had a tendency to be not dependent on the size of prosthesis (p = 0.63). In the article for the first time a morphometric database of geometric values of internal orifice area of normal native aortic valves in adults was used taking into account both the gender and the body surface area's of a patient. There was also used the standardized prosthesis size Z-score which represents the number of SDs by which the internal prosthesis area differs from the mean normal native aortic valve area for the patient's body surface area. The article emphasizes the need of the personal selection of the size and the type of prosthesis for any patient as well as the need for new design development of prosthetic heart valves.