FFR-Guided PCI Shows Differences in Long-Term Outcomes in Men, Women

Download this article's Factoid (PDF & PPT for Gold Subscribers)

Gender-based differences are prevalent among patients undergoing fractional flow reserve- (FFR) guided percutaneous coronary intervention (PCI), especially over the long-term, according to a study published online October 22, 2013, ahead of print in Circulation: Cardiovascular Interventions.

Amir Lerman, MD, of the Mayo Clinic (Rochester, MN), and colleagues retrospectively analyzed 1,090 consecutive patients (63% men) referred for FFR-guided PCI at their institution between October 2002 and December 2009. Median follow-up was 50.9 months.

Overall FFR adjusted by visual coronary stenosis in women was 0.011 points higher than in men (P = 0.03). When lesions were analyzed by percent diameter stenosis, FFR values were higher in women than in men only for lesions with 60%-69% stenosis (P = 0.03) and 70%-79% stenosis (P = 0.002).

In Kaplan-Meier analysis, the unadjusted 5-year incidence of MACE was similar in men and women (table 1).

Table 1. Unadjusted Kaplan-Meier Events at 5 Years

 

However, in patients undergoing PCI with FFR values < 0.75, the incidence of death or MI was higher in women vs. men (HR 2.16; 95% CI 1.04-4.51; P = 0.04). Additionally, deferring PCI in a lesion with FFR between 0.75 and 0.80 was associated with a greater risk of MACE in both women (HR 2.12; 95% CI 1.23-3.65; P = 0.007) and men (HR 2.16; 95% CI 1.39-3.34; P = 0.001), compared with patients with FFR greater than 0.80. These increases were driven by a higher incidence of death or MI in women (HR 3.25; 95% CI 1.56-6.74; P = 0.002) and need for revascularization in men (HR 2.66; 95% CI 1.66-4.54; P < 0.001).

Sex-Based Consideration Needed

The finding that women have a higher incidence of death or MI than men undergoing PCI in a vessel with FFR < 0.75 “is inconsistent with a recent substudy of the FAME study, which reported a comparable 2-year outcome after PCI in women and men,” according to the authors. They cite 3 potential reasons for this:

• The studies have different FFR thresholds for performing PCI
• Differences in outcome might be more prominent during the longer follow-up in the current study
• Observed sex-related differences might be somewhat attributable to the relatively lower number of patients in subgroups of the current study

Dr. Lerman and colleagues suggest that FFR values between 0.75 and 0.80 constitute a “gray zone,” and clinical judgment is required for revascularization decision-making in these cases.

They say two mechanisms may partly account for the higher rate of MACE driven by more hard events in women and more revascularizations in men. “First, some women with an actual FFR of < 0.75 and potentially worse outcome could have been misclassified to the higher FFR subset (0.75-0.80) attributable to submaximal hyperemia and deferred from PCI. Second, men with deferral of PCI were more likely to undergo revascularization in the follow-up attributable to more severe angiographic stenosis, as compared with women in the same FFR subset,” Dr. Lerman and colleagues note.

Since women were overall older than men, and the age difference could not be fully accounted for statistically, this “might have had an influence on outcome, probably in favor of men,” the authors report. “This may not diminish the robust results but could contribute to an overestimation of the outcome gap between women and men.”

Going forward, the authors recommend giving added consideration to the sex-based therapeutic target and treatment strategy to optimize outcomes for CAD patients.

No Clinical Implications

In a telephone interview with TCTMD, Massoud A. Leesar, MD, of the University of Alabama (Birmingham, AL), cited the DEFER study (Pijls NH et al. J Am Coll Cardiol; 2007), which looked at 5-year outcomes of patients who had FFR values of at least 0.75. “They did pretty well, and event rates were low,” he explained, although the study did not separate women and men. “But here all patients with FFR < 0.75 had increase event rates. . . . This is altogether surprising.”

Given the study’s retrospective nature, it “is not going to change your decision making whether to revascularize or not revascularize a patient,” he concluded.

Study Details

Generally, women were older, less likely to smoke, had a lower incidence of prior MI or CABG, and had less angiographic lesion severity compared with men.

 

---

Source:
Li J, Rihal CS, Matsuo Y, et al. Sex-related differences in fractional flow reserve-guided treatment. Circ Cardiovasc Interv. 2013;Epub ahead of print.

 

• Drs. Lerman and Leesar report no relevant conflicts of interest.

 

Related Stories

• FAME Substudy: FFR-Guided PCI Just as Beneficial for Women as Men
• Angiography May Overestimate Disease Severity vs. FFR in Women