Characterization of the Left Ventricle after Transcatheter Aortic Valve Implantation in Patients with Cardiovascular Disease - Abstract
Background: Aortic stenosis, the most common valve disease in developed countries, can be ameliorated through surgical replacement or transcatheter aortic valve implantation (TAVI). Our aim was to investigate functional recovery of the left ventricle after TAVI, including improvements in regional wall motion and scar formation, in patients with severe aortic stenosis, known cardiovascular disease and heart failure. Methods: Thirty patients with severe aortic stenosis and cardiovascular disease with heart failure who were referred for TAVI were prospectively enrolled in the study. These patients exhibited discrete midwall fibrosis and/or light fibrosis at the upper and lower insertion points. Before undergoing TAVI, cardiac magnetic resonance imaging (MRI) was performed using a 1.5-Tesla magnetic resonance scanner. A standard balanced steady-state free precession sequence with strain-encoded (SENC) imaging was used to assess left and right ventricular volumes. Late gadolinium enhancement imaging was performed 10 minutes after application of contrast agent. Three-month follow-up imaging was performed using an identical cardiac MRI protocol to characterize the left ventricle. Results: Three months after TAVI, global (p<0.01) and circumferential strain (p<0.03) were significantly improved. Left ventricular function was significantly increased at follow-up, and volumes were significantly reduced. No new scar formation or fibrotic tissue was detected. Conclusion: TAVI resulted in functional recovery in patients with cardiovascular disease and known heart failure by decreasing left ventricular volumes and increasing ejection fraction, and no new fibrotic tissue was generated.