Myocardial fibrosis and its relation to adverse outcome in transposition of the great arteries with a systemic right ventricle.

Background: Myocardial dysfunction has been implicated in gradual heart failure in transposition of the great arteries (TGA) with a systemic right ventricle (RV). Fibrosis can be assessed using the extracellular volume fraction (ECV). Our aim was to measure ECV and determine its associations with clinical findings and outcomes.

Late gadolinium enhancement cardiovascular magnetic resonance of the systemic right ventricle in adults with previous atrial redirection surgery for transposition of the great arteries.

Background: Patients treated for transposition of the great arteries by atrial redirection surgery have a right ventricle (RV) that sustains systemic pressures long term. Late RV dysfunction occurs in these patients; the reasons for this are unclear, but myocardial fibrosis may be important. Myocardial fibrosis can be visualized by late gadolinium enhancement (LGE) cardiovascular magnetic resonance (CMR).

Validation of the myocardial performance index by echocardiography in mice: a noninvasive measure of left ventricular function.

Background: The myocardial performance index (MPI) is a Doppler-based measure of left ventricular (LV) function. It is noninvasive, independent of LV shape, and does not require dimensional measurements. However, it has never been validated in mice.

Perinatal hypoxia causes ventricular enlargement associated with increased atrial natriuretic peptide (ANP) mRNA levels in newborn mice.

We sought to examine both the short-term and residual effects of perinatal hypoxia on ventricular mass and function of mice. We postulated that the magnitude of the ventricular hypertrophy would be determined by the timing of the exposure, be linked to augmented atrial natriuretic peptide (ANP) expression, and would persist to young adulthood. Furthermore, mice deficient in the ANP receptor type A (ANPRA) would have even greater hypertrophy.