Highlights
– A life cycle assessment (LCA) of 30 procedures found the carbon footprint of surgical aortic valve replacement (SAVR) is roughly twice that of transcatheter aortic valve replacement (TAVR) performed in either an operating room (OR-TAVR) or a catheterization laboratory (CATH-TAVR).
– Median total footprints: OR-TAVR 280–340 kg CO2e; CATH-TAVR 290–360 kg CO2e; SAVR 620–750 kg CO2e (P < .05 for SAVR vs either TAVR).
– The largest contributors were post-operative ICU and floor care (≈52–59% of total) and, for SAVR, inhaled anaesthetic gases and biological waste increased intraoperative emissions.
Background: disease burden and why emissions matter
Aortic stenosis is common in older adults and demand for aortic valve replacement is increasing with aging populations. Clinical decisions about treatment modality—surgical aortic valve replacement (SAVR) versus transcatheter aortic valve replacement (TAVR)—have traditionally focused on anatomy, perioperative risk, long-term outcomes, and cost. Climate change is now recognized as a major public health determinant, and health care is a substantial contributor to national greenhouse gas (GHG) emissions. Quantifying the environmental footprint of common procedures can identify high-yield targets for decarbonization and inform system-level decisions without undermining patient-centered care.
Study design
The study by Blitzer et al. (Eur Heart J. 2025) performed an LCA following ISO14067 standards to estimate total carbon footprints, expressed in kilograms of CO2 equivalents (kg CO2e), for three groups: SAVR (n = 10), OR-TAVR (n = 10), and CATH-TAVR (n = 10). Consecutive procedures between March and September 2023 were analyzed. The model used primary data on materials, procedural steps, and energy use across pre-operative, intraoperative, and post-operative phases. Patients undergoing concomitant procedures were excluded. The authors report a coefficient of variation of 10% for total footprints and up to 25% for individual life cycle stages, consistent with LCA practice.
Key findings
Population characteristics: median ages were 77 (OR-TAVR), 82 (CATH-TAVR), and 66 (SAVR) years. Median Society of Thoracic Surgeons (STS) predicted risk of mortality were 4.9% (OR-TAVR), 2.8% (CATH-TAVR), and 1.4% (SAVR). Ejection fraction was similar across groups.
Total life cycle carbon footprints (reported ranges):
- OR-TAVR: 280–340 kg CO2e
- CATH-TAVR: 290–360 kg CO2e
- SAVR: 620–750 kg CO2e (P < .05 vs either TAVR)
Phase-specific contributors:
- Post‑operative care (ICU + ward) accounted for the largest share: ~170 kg CO2e for OR-TAVR (≈55% of total), ~170 kg CO2e for CATH-TAVR (≈52%), and ~405 kg CO2e for SAVR (≈59%) (P < .05 SAVR vs either TAVR).
- ICU length of stay (LOS) was a dominant single contributor: ≈27% of OR-TAVR footprint, 25% of CATH-TAVR, and 43% of SAVR footprint.
- Intraoperative footprints: ~100 kg CO2e for OR-TAVR, ~103 kg CO2e for CATH-TAVR, and ~241 kg CO2e for SAVR. The SAVR intraoperative burden was driven by biological waste, longer post-operative LOS, and inhaled anaesthetic gases.
Interpretation: SAVR’s life cycle emissions were roughly double those of TAVR in either setting. The majority of emissions for all modalities accrued after the operation, primarily from hospitalization and critical care resource use.
Expert commentary: strengths and limitations
This study provides timely, granular data using primary measurement and ISO-aligned LCA methodology to compare three real-world procedural pathways. Strengths include using direct procedural data rather than pure modelling and explicitly quantifying phase-specific contributions (pre-op, intra-op, post-op). Reporting of coefficients of variation provides transparency about uncertainty that is common in LCAs.
However, several limitations must temper interpretation and policy translation:
- Sample size and representativeness: each arm included only 10 procedures from a single center over six months, which limits generalizability across institutions with different workflows, energy mixes (grid carbon intensity), device procurement, and post‑operative pathways.
- Case-mix differences: TAVR cohorts were older with higher STS risk scores overall; paradoxically, CATH-TAVR had a lower median STS risk than OR-TAVR in this cohort. Differences in patient selection and complications will influence LOS and resource use, which are major drivers of footprint.
- LCA boundaries and assumptions: although described as following ISO14067 and using primary data, LCAs are sensitive to system boundaries (e.g., how far upstream manufacturing, device supply chains, and end-of-life disposal are modeled). The reported analysis appears to include pre-op, intra-op, and post-op hospital phases, but variability in device manufacturing emissions across valve manufacturers and transport distances may materially change totals in different settings.
- Outcome and cost-effectiveness considerations: environmental metrics are important at a systems level but must be integrated with clinical outcomes, durability, patient preferences, and economic costs. Emissions should not override individualized clinical indications.
Clinical and policy implications
Key practical messages:
- TAVR pathways may carry lower in-hospital carbon footprints than SAVR largely because they are less invasive and generally require shorter ICU and overall hospital LOS. This suggests that, when TAVR and SAVR are clinically comparable, broader adoption of less resource‑intensive pathways can yield environmental co-benefits.
- Post-operative care—particularly ICU time—is a high-yield target for decarbonization. Enhanced recovery protocols, fast-track extubation, ICU avoidance or shortened ICU stays, and standardized post‑op pathways can reduce emissions while improving patient outcomes.
- Intraoperative opportunities include reducing reliance on high‑global‑warming-potential inhaled anaesthetics (substitute with total intravenous anesthesia when appropriate), optimizing waste segregation to reduce biological-waste processing, adopting reusable instruments where safe and cost-effective, and improving energy efficiency in procedural suites.
- Procurement and guideline development: at the population and health system level, environmental footprint should be considered alongside safety, efficacy, and cost. Procurement contracts and national guidelines can introduce environmental criteria (e.g., life-cycle emissions per device) to incentivize manufacturers to decarbonize supply chains.
Recommended next steps for research and practice
To move from a single-center LCA to actionable policy, priorities include:
- Multi-center LCAs capturing geographic variation in energy grids, supply chains, and clinical pathways.
- Standardized reporting frameworks for surgical and device LCAs to permit meta-analysis and benchmarking.
- Integration of environmental impact with cost‑effectiveness and long-term clinical outcomes (e.g., life-years gained per kg CO2e) to support value-based healthcare decisions that include planetary health.
- Interventional trials or quality-improvement programs testing decarbonization interventions (e.g., ERAS for SAVR, ICU avoidance protocols, anaesthetic stewardship) with concurrent measurement of clinical outcomes and emissions.
Conclusion
Blitzer et al. provide important empirical evidence that, in their dataset, SAVR has approximately double the in-hospital carbon footprint of TAVR performed in either an operating room or catheterization laboratory. The dominant drivers are post-operative ICU and ward care and, for SAVR, intraoperative waste and inhaled anaesthetics. These findings do not replace clinical decision-making but add a systems-level consideration: when clinical equipoise exists, lower-carbon pathways that deliver equivalent patient outcomes should be preferred. For broad impact, these data should inform multi-center studies, procurement policies, and targeted decarbonization strategies in perioperative care.
Funding and clinicaltrials.gov
No trial registration was reported in the source article. Funding sources and potential conflicts of interest should be reviewed in the original publication (Blitzer et al., Eur Heart J. 2025) for transparency.
References
1. Blitzer D, Meinrenken CJ, Apelgren NB, Chavez XS, Durrenberger O, Jagdish AS, Simpson M, Bowers N, James EI, Pirelli L, Lebehn M, Agarwal V, Ng V, Vahl T, Nazif T, Hahn RT, Kodali S, Leon MB, George I. Carbon emission analysis of aortic valve replacement: the environmental footprint of transcatheter vs. surgical procedures. Eur Heart J. 2025 Nov 21;46(44):4810-4819. doi: 10.1093/eurheartj/ehaf379. PMID: 40599126.
2. Eckelman MJ, Sherman JD. Environmental impacts of the U.S. health care system and effects on public health. PLoS One. 2016 Jun 15;11(6):e0157014. doi:10.1371/journal.pone.0157014.
3. World Health Organization. Climate change and health. WHO Fact sheet. 2021. Available at: https://www.who.int/news-room/fact-sheets/detail/climate-change-and-health (accessed 2025).
AI thumbnail prompt (for designers and generators)
A split-scene digital illustration: left side shows a busy cardiac operating room with a sternotomy in progress, surgical team in scrubs, visible surgical instruments and a waste bin labeled “biohazard” with faint rising CO2 molecule icons; right side shows a catheterization lab with a cardiologist performing TAVR under fluoroscopy, patient draped, smaller team, and lower visible waste. Central overlay: semi-transparent scale balancing a heart valve icon and a CO2 molecule, with muted hospital color palette and a clear, modern informational aesthetic.
