Impact of concomitant aortic regurgitation on long-term outcome after surgical aortic valve replacement in patients with severe aortic stenosis

<p>Abstract</p> <p>Background</p> <p>Prognostic value of concomitant aprtic regurgitation (AR) in patients operated for severe aortic stenosis (AS) is not clarified. The aim of this study was to prospectively examine the impact of presence and severity of concomitant AR in patients operated for severe AS on long-term functional capacity, left ventricular (LV) function and mortality.</p> <p>Methods</p> <p>Study group consisted of 110 consecutive patients operated due to severe AS. The patients were divided into AS group (56 patients with AS without AR or with mild AR) and AS+AR group (54 patients with AS and moderate, severe or very severe AR). Follow-up included clinical examination, six minutes walk test (6MWT) and echocardiography 12 and 104 months after AVR.</p> <p>Results</p> <p>Patients in AS group had lower LV volume indices throughout the study than patients in AS+AR group. Patients in AS group did not have postoperative decrease in LV volume indices, whereas patients in AS+AR group experienced decrease in LV volume indices at 12 and 104 months. Unlike LV volume indices, LV mass index was significantly lower in both groups after 12 and 104 months as compared to preoperative values. Mean LVEF remained unchanged in both groups throughout the study. NYHA class was improved in both groups at 12 months, but at 104 months remained improved only in patients with AS. On the other hand, distance covered during 6MWT was longer at 104 months as compared to 12 months only in AS+AR group (p = 0,013), but patients in AS group walked longer at 12 months than patients in AS+AR group (p = 0,002). There were 30 deaths during study period, of which 13 (10 due to cardiovascular causes) in AS group and 17 (12 due to cardiovascular causes) in AS+AR group. Kaplan-Meier analysis showed that the survival probability was similar between the groups. Multivariate analysis identified diabetes mellitus (beta 1.78, p = 0.038) and LVEF < 45% (beta 1.92, p = 0.049) as the only independent predictor of long-term mortality.</p> <p>Conclusion</p> <p>Our data indicate that the preoperative presence and severity of concomitant AR has no influence on long-term postoperative outcome, LV function and functional capacity in patients undergoing AVR for severe AS.</p

Symulacja danych medycznych jako sposób przyspieszenia rozwoju algorytmów systemu oceny stanu pacjenta

W artykule przedstawiono system wspomagania decyzji odnośnie do oceny stanu ogólnego pacjenta, ze szczególnym naciskiem położonym na choroby układu krążenia i układu oddechowego. Działanie tego systemu jest oparte na danych wejściowych ze standardowego monitora funkcji życiowych (w fazie rozwoju algorytmów dane są również symulowane). Sygnały są przetwarzane i analizowane za pomocą algorytmów opartych, przede wszystkim, na sieciach Bayesa. System na wyjściu powinien generować informację na temat wykrytych problemów, przyszłych zagrożeń, przyczyn pogorszenia zdrowia i propozycji dalszego leczenia.This paper presents decision support system for estimation of patient's general state, with particular stress laid on cardiovascular and pulmonary diseases. It works in conjunction with a standard medical monitor, which provides asset of input signals (for development stage signals are also simulated). The signals are preprocessed and analysed by a set of algorithms, the core of which is based on Bayesian networks. As an output the system should give information about detected problems, eventual future threats, possible causes and suggestions for further treatment