Flies expressing Atg2^KK100148 under the control of Scer\GAL4^Mef2.PU display climbing defects in both males and females, together with progressive heart defects: thicker heart walls and a distorted lumen with a rough surface in older flies, increased systolic dimension throughout adult life, increased diastolic dimension at day 40 and significantly reduced fractional shortening at day 40 (but not in younger flies). Mitochondria in cardiomyocytes are abnormally elongated and narrowed, the mitochondrial network appears fused/enlarged and the mitochondrial volume density is significantly increased in 40-day old flies. Alongside, indirect flight muscles display severe mitochondrial abnormalities: fragmented, enlarged or hollow mitochondria with significantly variable sizes and reduced mitochondrial volume density.