Evolution of Coronary Management in the TAVI Era
The management of coronary artery disease (CAD) in patients undergoing transcatheter aortic valve implantation (TAVI) remains one of the most debated topics in interventional cardiology. As TAVI indications expand to younger and lower-risk populations, the long-term impact of concomitant CAD and its optimal revascularization strategy become increasingly critical. Historically, coronary artery disease has been identified in up to 50% of patients presenting for aortic stenosis intervention. However, the elderly and often frail nature of the TAVI population introduces a complex benefit-risk calculation for percutaneous coronary intervention (PCI). While angiography has been the traditional gold standard for identifying coronary stenoses, it is well-recognized that visual assessment often correlates poorly with the functional significance of a lesion, particularly in the context of intermediate-grade stenoses (30-70%). This discrepancy is further magnified in patients with severe aortic stenosis, where altered hemodynamics—such as left ventricular hypertrophy, increased end-diastolic pressure, and microvascular dysfunction—can complicate the interpretation of coronary physiology.
The FAITAVI Trial: Bridging the Evidence Gap
Despite the widespread adoption of fractional flow reserve (FFR) in the general stable CAD population—supported by landmark trials like FAME and FAME 2—data specifically addressing its utility in the TAVI population have been sparse. The FAITAVI (Functional Assessment in TAVI) trial was designed to address this unmet need, providing a multicentric, randomized comparison between physiology-guided and angiography-guided revascularization strategies.
Highlights
The FAITAVI trial presents several landmark findings for the structural heart community: 1. FFR-guided PCI resulted in a nearly 50% reduction in the risk of major adverse cardiac and cerebrovascular events (MACCE) at 12 months compared to angiography-guided PCI. 2. The primary benefit was driven by a statistically significant reduction in all-cause mortality (HR 0.31). 3. Physiology-guided strategies reduced unnecessary interventions in this elderly, high-risk population, supporting a more targeted approach to revascularization.
Study Design and Methodology
The FAITAVI trial was a multicentric, open-label, randomized, superiority trial conducted across 15 Italian centers. It utilized blind adjudication of adverse events to minimize bias.
Patient Population and Inclusion Criteria
A total of 320 patients were enrolled. The cohort was characterized by advanced age (median 86 years; IQR 83-90) and a relatively low surgical risk profile (median STS score 3%). This reflects the modern ‘real-world’ TAVI population in Europe. Patients were included if they had severe aortic stenosis and at least one intermediate coronary lesion (defined as 30-70% diameter stenosis by visual estimation) in a vessel with a diameter of ≥2.5 mm.
Interventions and Comparators
Patients were randomized 1:1 to either an FFR-guided strategy or an angiography-guided strategy. In the FFR group, PCI was performed only if the FFR value was ≤0.80. In the angiography-guided group, PCI was performed based on visual estimation of the lesion severity, following standard clinical practice. The median SYNTAX score was 7, indicating a relatively low complexity of coronary disease in the study population.
Primary and Secondary Endpoints
The primary endpoint was MACCE at 12 months, a composite of all-cause death, myocardial infarction (MI), ischemia-driven target vessel revascularization (TVR), disabling stroke, or major bleeding. All endpoints were adjudicated by an independent committee blinded to the treatment assignment.
Detailed Results: A Victory for Physiology
The results of the FAITAVI trial suggest a clear clinical advantage for physiology-based decision-making.
Primary Endpoint Analysis
At the 12-month follow-up, the primary MACCE endpoint occurred in 8.5% of the FFR-guided group compared to 16.0% in the angiography-guided group. This represented a hazard ratio (HR) of 0.52 (95% CI 0.27–0.99; P = 0.047). The divergence in the event curves occurred relatively early and persisted throughout the one-year follow-up period.
Mortality and Safety Outcomes
Perhaps the most striking finding was the reduction in all-cause mortality. The FFR-guided group showed a significantly lower rate of death compared to the angiography group (HR 0.31; 95% CI 0.10–0.96). Other components of the composite endpoint, including MI, stroke, and major bleeding, were numerically lower in the FFR group but did not reach individual statistical significance. This suggests that the overall benefit of physiology-guided PCI may stem from a combination of avoiding unnecessary procedural risks (such as bleeding or periprocedural MI) and ensuring that only truly hemodynamically significant lesions—those that contribute to myocardial stress—are treated.
Expert Commentary: Navigating Hemodynamic Complexity
The FAITAVI trial provides critical evidence in a field where physiological assessment has been viewed with skepticism.
The FFR Paradox in Aortic Stenosis
For years, clinicians questioned the validity of FFR in the presence of severe aortic stenosis. The theoretical concern was that the increased left ventricular end-diastolic pressure and microvascular resistance associated with aortic stenosis would limit the ability to achieve maximal hyperemia, potentially leading to false-negative FFR results (underestimating lesion severity). However, recent physiological studies and now the FAITAVI trial suggest that while aortic stenosis does impact the microcirculation, FFR remains a robust and clinically relevant tool. By identifying which lesions are truly contributing to the ischemic burden, clinicians can avoid the ‘oculostenotic reflex’—treating lesions that look significant on film but do not actually compromise myocardial perfusion.
Clinical Implications for the Heart Team
In a population with a median age of 86, the ‘less is more’ philosophy often prevails. The FAITAVI results suggest that an FFR-guided approach allows for a ‘precision medicine’ strategy in coronary revascularization. By reducing the number of unnecessary stents, clinicians can potentially reduce the duration of dual antiplatelet therapy (DAPT), thereby lowering the risk of major bleeding—a major concern in the elderly TAVI population. Furthermore, the reduction in mortality suggests that treating only functional lesions may improve the overall cardiovascular reserve of these patients as they recover from the TAVI procedure.
Limitations and Future Directions
While the FAITAVI trial is a significant step forward, it is not without limitations. The trial was open-label, although the use of a blinded adjudication committee mitigated potential bias. The sample size, while sufficient for the primary endpoint, may not have been powered to detect differences in individual secondary outcomes like MI or stroke. Additionally, the study focused on intermediate lesions; the role of FFR in highly complex, multi-vessel CAD in TAVI patients warrants further investigation. Future research should also explore the use of non-hyperemic pressure ratios (NHPRs), such as iFR, which may be more convenient in the TAVI setting by avoiding the need for adenosine.
Summary and Clinical Takeaways
The FAITAVI trial provides strong evidence that a physiology-based revascularization strategy is superior to an angiography-based strategy for patients with intermediate coronary lesions undergoing TAVI. By utilizing FFR to guide PCI, clinicians can significantly reduce the risk of MACCE and all-cause mortality at one year. These findings support the integration of routine functional assessment into the pre-procedural planning for TAVI, particularly in the elderly and frail populations where the avoidance of unnecessary interventions is paramount.
Funding and Clinical Trial Registration
The FAITAVI trial was investigator-initiated and supported by various academic and clinical institutions in Italy. The trial is registered at ClinicalTrials.gov under the identifier NCT03360591.
References
1. Ribichini FL, Scarsini R, Pesarini G, et al. Physiology vs angiography-guided percutaneous coronary intervention in transcatheter aortic valve implantation: the FAITAVI trial. Eur Heart J. 2025 Dec 19:ehaf974. doi: 10.1093/eurheartj/ehaf974.
2. Tonino PA, De Bruyne B, Pijls NH, et al. Fractional flow reserve versus angiography for guiding percutaneous coronary intervention. N Engl J Med. 2009;360(3):213-224.
3. Barbato E, Toth GG, Johnson NP, et al. Aortic stenosis and coronary artery disease: physiology and angiography. EuroIntervention. 2014;10 Suppl U:U13-19.
