Mitochondrial ultrastructure in cardiac myocytes is associated with the cardiovascular death in patients with heart failure

Figure 1 Flow diagram for the study design. CABG: Coronary artery bypass grafting.

Figure 2 Micrograph of a cardiomyocyte from the auricle of the right atrium of a patient with ischemic heart failure (magnification × 5000). An example of delineation of mitochondria and interfibrillary space is shown (yellow line), which is used to calculate the “Total area of the interfibrillar mitochondria” indicator. A: Initial view; B: Yellow lines indicate the contours of mitochondria and the contour of the interfibrillar space.

Figure 3 Micrograph of a cardiomyocyte from the auricle of the right atrium in a patient with ischemic heart failure (magnification × 15000). An example of the separation of the inner and outer mitochondrial membranes is shown in the micrograph (yellow line), which can be used to calculate the ratio of the outer to inner mitochondrial membrane length. A: A yellow line outlines the outer membrane of a single mitochondrion; B: Yellow lines indicate the outer and inner membranes of three mitochondria.

Figure 4 Receiver operating characteristic curve of the “Ratio of mitochondrial membrane lengths” for predicting one-year mortality risk after coronary artery bypass grafting. Area under the curve = 0.907, 95% confidence interval: 0.808-0.999, P = 0.002. ROC: Receiver operating characteristic.

Figure 5 Micrographs of a cardiomyocyte from the auricle of the right atrium in two patients with ischemic heart failure (magnification × 15000). Yellow lines indicate the outer and inner membranes of three mitochondria for each patient to calculate the “Ratio of mitochondrial membrane lengths”. A: Micrograph of the myocardium of a surviving patient, where the “Ratio of mitochondrial membrane lengths” was 21%; B: Micrograph of the myocardium of a deceased patient, where the “Ratio of mitochondrial membrane lengths” was 53% (a predictor of mortality).