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

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).