Left ventricular global longitudinal systolic function predicts mortality in sepsis independent to the shock index

Vittorio Palmieri, Francesca Innocenti, Aurelia Guzzo, Chiara Donnini, Valerio T. Stefanone, Riccardo Pini


Background: Whether left ventricular (LV) global longitudinal systolic dysfunction refines risk stratification in sepsis/septic shock independent to shock index is unknown.
Methods: Shock index [(SI), heart rate (HR)/systolic blood pressure (BP), bpm/mmHg], LV global longitudinal strain (GLS, 2D-speckle-traking-based, %), ejection fraction (EF, by planimetry), Sepsis-related Organ Failure Assessment (SOFA) score, and blood tests were assessed in patients with sepsis/septic shock at the admission in the Emergency Department. Follow-up was performed at 7 and 28 days from admission, accounting for all-cause mortality, major co-morbidities and SOFA ≥2.
Results: In consecutive patients meeting inclusion criteria (n=123, 79% of the cohort), SI was <0.7 in 48 patients (39%, i.e., without hemodynamic instability), 50 (41%) had possible hemodynamic instability by SI between 0.7 and 0.99, 25 (20%) had hemodynamic instability by a SI ≥1. More abnormal GLS, and not SI, predicted mortality day-28 follow-ups (adjusted hazard ratio 1.3 per 1% of GLS closer to 0, P<0.05) independently of age, comorbidities and SOFA ≥2; a consistent trend was found with mortality data at day-7 follow-up (adjusted hazard ratio=1.3, P=0.05). LV end-diastolic volume index, cardiac index, systemic vascular resistance index and the peak velocity of the mitral E wave did not differ according to SI-strata. Age, body mass index, GLS and EF did not differ among SI groups, whereas female gender tended to be higher with higher SI (all P>0.5). Prevalence of SOFA ≥2, of diabetes, coronary heart disease (CHD), and chronic kidney dysfunction were comparable among SI groups; prevalence of cancer was lowest in the group of patients with low SI, chronic obstructive pulmonary disease (COPD) was higher with high or low SI. Blood lactate at admission tended to be higher with SI ≥1 than <0.7 while troponin did not differ among SI groups.
Conclusions: In sepsis/septic shock, LV GLS and not SI predicted all-cause mortality at day-28 follow-up independently of SOFA ≥2 and major co-morbidity.