Does reporting of global longitudinal strain impact clinical decisions in patients undergoing echocardiography as part of chemotherapy monitoring?
Ali M, Al-Darzi W, Bryan A, Joseph N, Nakhle A, Motwani A, Mahan M, Ananthasubramaniam K. Does reporting of global longitudinal strain impact clinical decisions in patients undergoing echocardiography as part of chemotherapy monitoring? J Am Coll Cardiol. 2018;71(11)
Background: Chemotherapy cardiotoxicity is a signifcant ongoing issue in cancer patients undergoing therapy. Global longitudinal strain (GLS) by echo is believed to detect subclinical cardiotoxicity. However, it is unclear what the impact of reporting these numbers on downstream patient management is. Our study evaluated the impact ofreporting GLS values in patients undergoing chemotherapyat a large tertiary center. Methods: In a retrospective study, we gathered data for 105 cancer patients on chemotherapy. Patient demographics and clinical data including ejection fraction (EF), GLS value, and grade of diastolic dysfunction (DD) pre and post chemotherapy were collected. Downstream patient management including cardiology referrals, chemotherapy modifcation and/or discontinuation, and initiation of cardioprotective medications were evaluated as endpoint outcomes. Results: Patients with abnormal baseline GLS values (N=18) were more often men (p=0.04) with lower EFs (58% vs 63%, p=0.01) and greater DD (p=0.01) than those with normal GLS values. Those with abnormal GLS values had more cardiology referrals (N=27, p <0.001), more chemotherapyinterruptions (p <0.001), and were more often initiated on cardiac medications (ACEi p=0.03, Beta Blocker p <0.001). Patients with abnormal baseline GLS values also had decreased follow-up GLS values (p <0.001). Patients who had at least one of the three end-point impact outcomes (N=43) had a lower mean follow-up GLS of 17.0 vs 19.7 inthe control group, and mean EF of 58.2% vs 61.7% in the control group. A multivariable study demonstrated an OR = 1.38 (95% CI 1.17, 1.63; p <0.001) of having one of the endpoint outcomes per unit decrease in GLS value. Conclusion: Our single center study has demonstrated that reporting GLS values has a signifcant downstream clinicalimpact, including a greater number of cardiology referrals, medication initiations and chemotherapy interruptions when GLS values are abnormal, even when EF values were normal. This may have clinical implications in the future interms of ensuring that GLS values are internally validated with ongoing quality control, as they can affect patient care.