AIMS: Plasmalemmal Ca-ATPase (PMCA) is involved in Ca handling and the regulation of intracellular signalling pathways in the heart. However, there is no information on its functioning in heart hypertrophy and failure. We aimed to investigate the Ca-transporting ability of PMCA, Na/Ca exchanger (NCX), and sarcoplasmic reticulum (SR) Ca-ATPase (SERCA2a), as well as the amplitude of Ca transients and cell shortening in myocytes isolated from rat hearts at various time intervals after myocardial infarction (MI). METHODS AND RESULTS: The rate of Ca transport by PMCA, NCX, and SERCA2a was estimated from the rate constants of decay of electrically and caffeine-evoked Ca transients in left ventricular myocytes isolated 1 week, 1 month, and 3 months after MI. One week, 1 month, and 3 months after MI, the transporting function of PMCA decreased by 27, 41, and 67%, respectively, compared with that in time-matched sham animals. This was accompanied by increased amplitude of Ca transients, cell shortening, and SR Ca content. Carboxyeosin, a blocker of PMCA, increased the amplitude of shortening in cells extracted from control hearts. This effect was absent 1 and 3 months after MI. PMCA1, 2, and 4 mRNAs were unchanged in the ventricular muscle 3 months after MI when compared with time-matched sham animals. The transporting function of NCX was increased by 65% only 3 months after MI, whereas that of SERCA2a was decreased by ∼18% at all three time points after MI. CONCLUSION: The ability of PMCA to transport Ca progressively decreases over 3 months after MI. This decrease may contribute to the increase in amplitude of Ca transients and myocyte shortening.