Mitral Regurgitation

Abstract

Background-A number of phosphorus ( 31 P) magnetic resonance spectroscopy (MRS) studies link alterations of high-energy phosphate metabolism in valvular disease and cardiomyopathy to the clinical severity of heart failure. However, correlations between MRS and indexes of ventricular dysfunction are inconclusive to date. We examined whether changes in 31 P MRS are associated with the impaired contractility, which predisposes to chronic congestive heart failure in patients with mitral regurgitation. Methods and Results-Thirteen normal control subjects and 22 patients with echocardiographically characterized chronic mitral regurgitation were studied by 31 P MRS. The apical phosphocreatine-to-ATP ratio (PCr/ATP) was lower in severe disease (PϽ.02) and those on therapy (nϭ13, 1.29Ϯ0.29, PϽ.01) in contrast to control subjects (nϭ13, 1.61Ϯ0.3). Compared to those with mild mitral regurgitation, patients with more severe incompetence had lower mean myocardial PCr/ATP ratios (mild, nϭ6,

Persistent Long-Term Structural, Functional, and Metabolic Changes After Stress-Induced (Takotsubo) Cardiomyopathy

“… 3 The phosphocreatine/γ-adenosine triphosphate (PCr/γATP) ratio (which is the gold standard for in vivo assessment of myocardial energetic status) 9 was determined after the γATP was corrected for blood contamination and PCr/γATP ratios were saturation-corrected as described previously. 10 – 12 To ensure that spectra were of good quality, Cramér-Rao standard deviations of all peaks were calculated, and only those <20% were accepted. The CMR images were analyzed in CMR Tools (Cardiovascular Imaging Solutions) for computation of left ventricular volumes and mass.…”

Mitochondria in the human heart

“…A low phosphocreatine-to-ATP ratio (PCr/ ATP), indicating a cardiac energy deficit, has been shown in the failing human heart (Beer et al 2002;Conway et al 1991;Hardy et al 1991;Neubauer et al 1997;Neubauer et al 1992). This ratio is correlated with clinical symptoms (Conway et al 1998) and predicts mortality better than the left ventricular ejection fraction (Neubauer et al 1997). As the main energy source, mitochondria are suspected to be at least in part responsible for the low energy reserve in the failing heart (Mettauer et al 2006).…”

Metabolic manipulation in chronic heart failure: study protocol for a randomised controlled trial

“…The concentrations of PCr, ATP (γ, α and β) and 2,3-diphosphoglycerate (2,3-DPG) will then be calculated as the area under the peaks. PCr/ATP ratio will be determined after correcting the γ ATP peak for blood contamination as described previously based on the quantity of 2,3-DPG in the derived spectrum[13]. A single, blinded operator experienced in the technique will perform analysis.…”