Left Ventricular End-Diastolic Diameter Predicts Clinical Outcomes in Patients Supported With Surgically Implanted...

This study sought to determine the impact of left ventricular size on clinical outcomes after a microaxial flow pump was surgically implanted.

In this retrospective cohort study, we included patients who received a surgical microaxial left ventricular assist device from May 2020 to February 2024 at 2 high-volume centers in the United States. Patients were categorized into 2 groups based on their preimplant left ventricular end-diastolic diameter (LVEDD): "small LVEDD," defined as LVEDD ≤5.5 cm, and "large LVEDD," defined as LVEDD >5.5 cm, respectively. End points were all-cause death at 30 days after device implantation, in-hospital death, death 30-days after discharge, and survival at 30-month follow-up.

Two-hundred sixty-two patients received an Impella 5.5. Preimplant LVEDD was documented in 194 (74%) patients, where 50 patients had LVEDD ≤5.5 cm and 144 patients had LVEDD >5.5 cm. Patients with a small LVEDD had a higher rate of all-cause death at 30 days after device implantation (32% versus 11.8%, P=0.002), in-hospital death (42% versus 20.1%, P=0.004), and death 30 days after discharge (44% versus 20.8%, P=0.003). In adjusted analyses, patients with a greater LVEDD had 62% decreased risk of long-term death (hazard ratio, 0.39 [95% CI, 0.19-0.76]; P=0.001), compared with patients with a smaller LVEDD.

In this real-world, all-comer study, we found that patients with reduced left ventricular dimension who required an Impella 5.5 had worse outcomes. Further research is warranted to recapitulate our observations across more centers.