STENOSI VALVOLARE AORTICA STUDIO DEGLI OUTCOME ECOCARDIOGRAFICI DOPO INTERVENTO DI CORREZIONE CHIRURGICA E VALUTAZIONE DELLA PREDITTIVITA’ DI COMPLICANZE TACHIARITMICHE ATRIALI POSTOPERATORIE DEI “NUOVI INDICI ECOCARDIOGRAFICI”

Background: The hemodynamic advantages of the surgical aortic valve replacement on the mass regression, left ventricular sistolic and diastolic function, the timing and the influence of PPM on these outcomes are the first aim of this echocardiographic study. Postoperative atrial fibrillation (POAF) is a common and clinically relevant complication after surgical aortic valve replacement (AVR), however it is hardly predictable. Aim of the study was also to test the role of pre-operative left atrial (LA) longitudinal strain as a predictor of POAF in clinical practice. Methods: Patients referred for AVR for severe isolated aortic valve stenosis were prospectively enrolled and underwent a clinical, biochemical and transthoracic echocardiographic assessment before and after surgery ( follow-up 12 months). Left ventricular mass, systolic and diastolic function, left atrial strain derived PALS (peak atrial longitudinal strain) and PACS (peak atrial contraction strain) were obtained. Results: Prospectively enrolled patients were 91. The follow-up was possible for 72 of them. Severe PPM (EAOi <0.65 cm2 / m2) was found in 12 (16.6%) patients. There was no statistical modification in the average ejection fraction between pre and post-intervention (FE 59% vs 62%, p 0.008). Left ventricular mass showed a reduction of approximately 24.7% (67g) at the 1st month, a further slight reduction at 6 months, remaining unchanged between 6 and 12 months. In a multivariate model, the preoperative mass ( r 0.21 p 0.032)and the 6 months valve area (r2 0.644 <0.001) were the only factors significantly related to the mass regression at 6 months; Immediate improvement of diastolic function was seen at the first month post-intervention (97.3% of patients). No significant difference was found in the improvement of diastolic function between the groups with or without PPM (p 0.641). b) POAF was present in 34 (48%) of the patient. Age was the only clinical variable significantly related with POAF (p=0,04), whereas pre-operative symptoms, cardiovascular risk factors, medications, or biochemical data showed no-link to POAF. Regarding echocardiographic parameters, only PALS and PACS indexes revealed a strong, significant association with the occurrence of arrhythmia (p<0,0001). Cut-off of 23% for PALS and 10% for PACS had the best sensitivity (92% for PACS) and specificity. In two comprehensive multivariate models, PALS and PACS remained significant predictors of POAF (OR:0.72 [0.58-0.89], p=0,002; and OR:0.69 [0.55-0.88], p=0,003). No significant interaction was detected between PALS or PACS and other clinical and echocardiographic variables, including age, E/E’ ratio, left atrial enlargement. Conclusions: This study indicates that adequate surgical timing allows early, significant mass regression and optimal recovery of diastolic function in short and medium postoperative times. PALS and PACS indexes are routinely feasible and useful to predict POAF when applied to the real-world clinical practice. Given the absence of any cue beyond age, LA strain should be routinely considered to assess the pre-operative risk of POAF.