Changes in myocardial density during postinfarction healing: effect on estimation of in vivo left ventricular mass by echocardiographic imaging

Abstract

To determine whether changes in density (rho) of infarct and noninfarct zones during healing and remodeling after myocardial infarction influence estimates of left ventricular mass and detection of temporal changes by imaging, we measured weights (g) and volumes (mL) of infarct, noninfarct, and mixed tissue in hearts removed 1 to 42 days after anterior infarction in three groups of dogs: nonreperfused infarction treated with placebo or captopril, or infarcts reperfused after 2 h. In vivo mass was calculated from in vivo diastolic myocardial volumes (echocardiograms) and an assumed density of 1.05 g/mL or actual values derived from tissue weights and volumes. Over the 42 days, actual density deviated more from the assumed value of 1.05 in infarct than noninfarct zones, and the overall density was higher for reperfused than nonreperfused ventricles (1.09 vs. 1.06 g/mL, p < 0.01). Correction for density improved the correlation between absolute in vivo and postmortem mass slightly but not the detection of relative changes in mass in control, captopril, or reperfusion groups. These findings suggest that (i) densities of infarct and noninfarct zones differ and change during healing, especially after reperfusion, and (ii) correction for density provides more accurate estimates of volume-derived mass in reperfused hearts.

Myocardial Contraction Fraction by M-Mode Echocardiography Is Superior to Ejection Fraction in Predicting Mortality in Transthyretin Amyloidosis

“…However, the main objective of the present study was to demonstrate that MCF, even if measured with the simplest method, can predict adverse outcomes. Additionally, measurement of MV relied on assuming a consistent myocardial density of 1.04g/mL regardless of amyloid presence, which is unlikely since myocardial density is known to vary with other conditions such as after infarction, when density has been shown to increase [52]. Finally, lacking data in the THAOS database on other known predictors of outcomes in light-chain cardiac amyloidosis, including strain [31-33], tricuspid phase annular plane systolic excursion [35], left atrial volume and function [53], and Left ventricular wall thickness [54], precluded their direct comparison with MCF.…”

Optimal Iodine Staining of Cardiac Tissue for X-Ray Computed Tomography

“…Since tissue structure [20]–[23] and density [24]–[26] have only a small amount of variation across species, can be expected to stain cardiac tissue in a similar way across species.…”

Myocardial fibrosis detected by cardiac CT predicts ventricular fibrillation/ventricular tachycardia events in patients with hypertrophic cardiomyopathy

“…To obtain MF mass, the MF volume was multiplied by myocardial-specific density, that is, 1.05 g/mL. 46 Percentage of MF was calculated as MF divided by LV mass. Basal and mid inferoseptal segments had significant metal artifacts in all patients and were excluded from analysis (Fig.…”