Self-expandable valves (SEV) were associated with a lower frequency of prosthesis-patient mismatch (PPM) compared with balloon-expandable valves (BEV), according to research presented during TCT 2019 and simultaneously published in JACC: Cardiovascular Interventions. Researchers led by Taishi Okuno, MD, said the difference was primarily driven by obese patients.

The study compared a total of 757 patients treated with SEV and BEV between August 2007 and June 2017. Researchers classified PPM based on discharge prosthetic effective orifice area indexed to BSA as severe (<0.65 cm2/m2) or moderate (0.65 to 0.85 cm2/m2) in the general population, and as severe (<0.60 cm2/m2) or moderate (0.60 to 0.90 cm2/m2) in the obese population (BMI ≥ 30 kg/m2).

Overall results showed SEV were associated with a lower incidence of PPM (PPM: 33.5 percent vs. 46.9 percent; severe PPM: 6.7 percent vs. 15.6 percent). In particular, researchers highlighted the significant difference between SEV and BEV in patients with BSA >1.83 m2. The also noted that "SEV had a preventative effect on PPM as compared to BEV in general and even in patients with relatively larger annulus size."

While there was no significant difference in patients with BSA ≤1.83 m2, as well as no impact of PPM on cardiovascular mortality or NYHA functional class at one year, researchers did recommend further investigation "to evaluate the clinical significance of PPM."

In a related editorial comment, Howard C. Herrmann, MD, FACC, calls the findings "encouraging" and notes "the strength of this analysis is the use of propensity matching to balance baseline characteristics between the groups," resulting in inclusion of 224 matched pairs. "Awareness and prediction of the risk of severe PPM after TAVR is a key first step," he writes. "As new and additional TAVR prostheses become available, utilization of the one with the largest suitable effective valve orifice area for a patient at risk for PPM should become an important point for discussion in our heart team meetings."

Clinical Topics: Invasive Cardiovascular Angiography and Intervention, Interventions and Imaging, Angiography, Nuclear Imaging

Keywords: TCT19, Transcatheter Cardiovascular Therapeutics, Angiography

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