Novel insights into the use of non-invasive imaging in Valvular Heart Disease

Abstract

This thesis aimed to improve the echocardiographic characterization of valvular heart disease by refining the assessment of tricuspid regurgitation (TR) and developing novel non-invasive markers of myocardial performance. First, new approaches to TR classification and grading were investigated. The ratio between vena contracta and tricuspid annular diameter introduced the concept of disproportionate TR, identifying patients with regurgitation exceeding the degree expected from annular dilatation and providing improved prognostic stratification. A hierarchical algorithm integrating vena contracta and effective regurgitant orifice area further refined TR grading and demonstrated the adverse prognostic significance of torrential TR.

The second part of the thesis explored novel echocardiographic markers of cardiac performance. Right ventricular–pulmonary artery coupling, assessed by the TAPSE/PASP ratio, provided incremental prognostic information in patients with significant TR. A novel estimate of right ventricular wall tension, derived from PASP and right ventricular length, was associated with adverse remodeling and clinical outcomes. In severe aortic stenosis, non-invasive myocardial work indices identified maladaptive left ventricular remodeling and advanced heart failure symptoms. Finally, the left atrioventricular coupling index, based on the ratio of minimal left atrial volume to left ventricular end-diastolic volume, emerged as a marker of diastolic dysfunction and prognosis in heart failure.