Cardiovascular aging is characterized by progressive loss of regulatory capacity, reduced physiological reserve, and increased vulnerability to stress and disease. Resting heart rate (RHR) and heart rate variability (HRV) provide complementary measures of cardiac automaticity and autonomic regulation, capturing important dimensions of cardiovascular aging. Comparative and epidemiological evidence demonstrates that elevated RHR and reduced HRV predict morbidity and mortality across species and human populations, reflecting cumulative physiological stress and declining regulatory function. Biological pathways associated with these autonomic phenotypes include sympathetic overactivation, parasympathetic withdrawal, neuroendocrine dysregulation, impaired baroreflex function, chronic inflammation, oxidative stress, and mitochondrial dysfunction. Clinical and mechanistic studies indicate that behavioral interventions (e.g., exercise and dietary modulation), pharmacological therapies, and neuromodulatory approaches can favorably influence RHR and HRV, although their causal effects on aging trajectories remain uncertain. Recent advances in wearable technologies and machine-learning-based phenotyping enable continuous assessment of autonomic function in both research and real-world settings. Integrating RHR and HRV into geroscience frameworks may help link autonomic regulation with fundamental aging mechanisms and cardiovascular risk. As accessible, noninvasive measures of physiological resilience and adaptability, RHR and HRV have potential value for advancing precision approaches to healthy cardiovascular aging and longevity.