The prognostic value of free triiodothyronine/free thyroxine ratio in short-term outcomes after left ventricular assist device implantation

Abstract

Background: Despite advancement in technology adverse events after left ventricular assist device(LVAD) implantation continue to be the main barrier to more widespread use of it. Therefore, it is vital to identify prognostic factors to reduce adverse cardiac events after LVAD implatation. Thyroid dysfunction is associated with a poor prognosis in individuals with heart failure. The objective of this study is to examine the correlation between thyroid hormones and adverse cardiovascular events following LVAD implantation. Method and Results: The study included a total of 36 patients, with an average age of 60 ± 9 years, of which 77.7% were male. Although there was no significant relationship between TSH and FT3 levels and post-operative adverse events(p>0.05 for both), there was a significant association between FT3/FT4 and all-cause and cardiovascular mortality(p<0.001 for both). ROC analysis revealed that FT3/FT4 values lower than 1 were significantly associated with adverse events(all p < 0.05). There was no significant difference between the two groups in terms of age, gender, BMI, etiology of heart failure, EF, sPAP, smoking status and the presence of comorbid diseases, BNP, TSH and FT3 levels(p>0.05 for all). All-cause mortality, cardiac mortality, arrhythmia prevelance, vasopressor need(day) and duration of ICU stay were significantly higher in FT3/FT4 < 1 group(all p < 0.05). Conclusion: Our findings suggest that FT3/FT4 ratio might be useful as a biomarker of short-term adverse clinical outcomes in patients who underwent LVAD implantation.

Keywords

• Left ventricular assist device
• Heart failure
• Thyroid disfunction; FT3/FT4 ratio; Cardiac mortality

References

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