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Thyroid hormone, amiodarone therapy, and prognosis in left ventricular systolic dysfunction
M Coceani1, S Molinaro, M Scalese
1Fondazione G. Monasterio CNR - Regione Toscana, Pisa, Italy. michecoc@ifc.cnr.it
Journal of Endocrinological Investigation
|November 20, 2010
Summary
Low T3 syndrome (LOWT3) worsens outcomes in patients with left ventricular systolic dysfunction (LVSD). Amiodarone therapy does not alter this negative impact on prognosis for LVSD patients with LOWT3.
Area of Science:
- Cardiology
- Endocrinology
- Pharmacology
Background:
- Amiodarone is used for arrhythmias in left ventricular systolic dysfunction (LVSD).
- Amiodarone can cause thyroid dysfunction by inhibiting T4 to T3 conversion.
- Low T3 syndrome (LOWT3) is associated with increased mortality in LVSD patients not on amiodarone.
Purpose of the Study:
- To investigate the relationship between thyroid hormone status, amiodarone use, and patient outcomes in LVSD.
- To compare mortality rates among patients with LVSD, LOWT3, amiodarone therapy, or a combination.
Main Methods:
- 2344 patients with LVSD, without overt thyroid disease, were categorized into four groups.
- Groups included: LOWT3 with amiodarone, isolated amiodarone, isolated LOWT3, and controls.
- Outcomes were assessed over a mean follow-up of 31 months using Kaplan-Meier and Cox analyses.
Main Results:
- Groups with LOWT3 (with or without amiodarone) and amiodarone alone showed increased total and cardiac mortality compared to controls.
- Survival was significantly reduced in patients with LOWT3, irrespective of amiodarone use.
- The effect of amiodarone alone on long-term prognosis was inconclusive due to limited patient numbers.
Conclusions:
- Low T3 syndrome negatively impacts prognosis in patients with LVSD.
- Concomitant amiodarone therapy does not modify the adverse prognostic effect of LOWT3 in LVSD.
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