New Technique in Assessment of Heart Chambers Remodeling in Acquired Mitral Valve Defects

Objective: Analysis and presentation of the capabilities of the new ultrasound technique —the index of volume remodeling (IRV), which allows comprehensive assessing of pathological remodeling of the heart as an integrated functional anatomical system. Materials and methods: For this study 316 patients with acquired mitral valve disease (MVD) were examined prior to and following mitral valve replacement with bileaflet, disc-, and bioprostheses. Key parameters of the heart were measured in classical echocardiographic projections (end systolic area, end-diastolic area, end systolic volume, and end diastolic volume of ventricles, ventricular ejection fraction, atrial volume, and the ratio of ventricular to atrial volumes). The patients were examined 1–2 days prior to and following the surgery—before discharge, 6 months later, 1 year later, and then annually within next 5 years. The examination data were collected in one- and two-dimensional modes by using Philips EpiQ-7, iE33, HDI, Siemens Acuson, and HP Sonos 2500 diagnostic ultrasound machines equipped with 2.5 and 3.5 MHz transthoracic sensors. Results: A comprehensive study of structural geometric remodeling parameters of heart cavities in the context of acquired MVD allowed identifying new patterns in changes of the heart chambers geometry. These changes are reflected in the IRV, a digital indicator of the severity of cardiac pathological remodeling. Analysis of the dynamics of post-operative vs. pre-operative IRV-based remodeling data also showed that the index is highly sensible to the hemodynamic features of through-flows in various designs of prostheses. The IRV has a pronounced prognostic power and allows predicting the long-term outcome of surgical treatment with an accuracy of 82.35%. Conclusions: The IRV predictive accuracy formed the basis of the original classification of types of cardiac remodeling, which can assist both in determining the optimal timing for surgery, and in conjunction with other clinical diagnostic data, in predicting the long-term outcome of heart geometry restoration depending on the type of surgical correction. The IRV can be used in evaluation of the heart geometry for any cardiac pathology. It makes the approach to the analysis of pathological remodeling of the heart understandable, consistent, and universal, and also opens up opportunities for further expanding the diagnostic capabilities of radiology in cardiac surgery at all stages of the diagnostic process.