Dog walking is emerging as a potential intervention in cardiovascular health. Meta-analyses and cohort studies suggest an association between dog walking and reduced cardiovascular mortality in patients with established diseases. Beyond physical activity, human-animal interactions favorably influence stress regulation, neuroendocrine balance, exercise motivation, and social connectedness. These synergistic mechanisms remain incompletely quantified, relying on observational associations. Dog walking represents a relevant, low-cost, and sustainable complement to conventional phase III cardiovascular rehabilitation strategies. This review synthesizes the available evidence and discusses its clinical implications in secondary prevention.