Extreme heat is an escalating climate-health hazard in the United States. However, its health effects remain uneven because exposure intersects with housing quality, energy insecurity, chronic illness, outdoor work, transportation barriers, limited tree canopy, and historical disinvestment. This study combines an integrative evidence synthesis with an exploratory ecological secondary analysis of publicly reported Centers for Disease Control and Prevention data for the 10 U.S. Department of Health and Human Services regions. The analysis examined regional mean warm-season 2023 heat-related illness emergency department (HRI ED) visit rates, 2018–2022 baseline rates, and the number of 2023 days above each region’s historical 95th percentile. Elevated day counts and 2023 regional rates were strongly correlated (Pearson r = 0.874, p = 0.001; Spearman rho = 0.924, p < 0.001), as were baseline and 2023 rates (Pearson r = 0.938, p < 0.001). Conventional ordinary least squares models showed strong associations, but heteroscedasticity-robust estimates and influence diagnostics indicated that the adjusted elevated-day coefficient was unstable in this small sample. The analysis therefore demonstrates regional clustering in the surveillance measures rather than causal or independently predictive effects. The evidence synthesis supports a five-pillar framework linking hazard anticipation, social vulnerability mapping, targeted intervention, adaptive risk communication, and ethical governance. Artificial intelligence can strengthen heat-risk management when it is locally validated, transparent, privacy-protective, and connected to funded interventions such as functional cooling, energy assistance, worker protections, transportation, wellness checks, resilient housing, and urban heat mitigation. AI should operate as accountable decision support rather than replace operational meteorology, public-health expertise, or community knowledge.