Respiratory motion is a major limiting factor for the application of cardiac proton MR spectroscopy (MRS) in clinical settings. Prospective navigator gating is frequently applied to minimize respiratory motion effects. However, scan durations are subject-dependent and hence difficult to predict. The present work describes cardiac proton MRS with fixed scan time employing retrospective phase-based gating. It is demonstrated that, relative to prospective navigator gating, the phase-based gating approach provides comparable triglyceride-to-water ratios with predictable scan time.