Prediction of adverse cardiac events in dilated cardiomyopathy using cardiac T2* MRI and MIBG scintigraphy

Abstract

Iron deficiency and cardiac sympathetic impairment play a role in the worsening of heart failure, and these two conditions may be linked. The present study aimed to clarify the relationship between myocardial iron deficiency, cardiac sympathetic activity, and major adverse cardiac events (MACE) in patients with dilated cardiomyopathy (DCM). Cardiac T2* MRI for iron deficiency and (123)I-Metaiodobenzylguanidine (MIBG) imaging for cardiac sympathetic activity were performed in 46 patients with DCM. Myocardial T2* value (M-T2*) was calculated by fitting signal intensity data for mid-left ventricular septum to a decay curve using 3-Tesla scanner. (123)I-MIBG washout rate (MIBG-WR) was calculated using a polar-map technique with tomographic data. We analyze the ability of M-T2* and MIBG-WR to predict MACE. MIBG-WR and M-T2* were significantly greater in DCM patients with MACE than in patients without MACE. Receiver-operating-characteristics curve analysis showed that the optimal MIBG-WR and M-T2* thresholds of 35 % and 28.1 ms, and the two combination predict MACE with C-statics of 0.69, 0.73, and 0.82, respectively. Patients with MIBG-WR <35 % and M-T2* <28.1 ms had significantly lower event-free rates than those with MIBG-WR ≥35 % or M-T2* ≥28.1 ms (log-rank value = 4.35, p < 0.05). Cox hazard regression analysis showed that χ(2) and the hazard ratio were 3.99 and 2.15 for development of MACE in patients with MIBG-WR ≥35 % or M-T2* ≥28.1 ms (p < 0.05). Iron deficiency, expressed by a high M-T2*, and MIBG-WR were both independent predictors of MACE in patients with DCM. The two combination was a more powerful predictor of MACE than either parameter alone.

Investigation and treatment for iron deficiency in heart failure: the unmet need in Lower and Middle Income Countries

“…Low myocardial iron can be determined directly, at least semi-quantitatively. Cardiac magnetic resonance imaging studies show that low myocardial iron (as measured by myocardial T2* imaging) was associated with non-ischaemic heart failure (Nagao et al, 2014(Nagao et al, , 2015 While there may be multiple pathways through which iron deficiency can impair cardiac function, tissue Doppler and strain rate measurements show significant improvements in diastolic and systolic myocardial function in iron-deficient patients after iron replacement therapy (Gaber et al, 2012).…”

Left ventricular ejection fraction recovery in patients with heart failure treated with intravenous iron: a pilot study

“…Cardiac magnetic resonance (CMR) T2* sequence has emerged as a reliable non‐invasive technique for assessing myocardial iron overload 7, 8. Recently, this technique has also shown a potential utility for evaluating myocardial iron deficiency 9, 10…”

“…7,8 Recently, this technique has also shown a potential utility for evaluating myocardial iron deficiency. 9,10 Aims We aimed to evaluate whether (i) T2* sequence significantly changes after intravenous iron administration in patients with ID with HFrEF, and (ii) if such changes correlate with simultaneous changes in CMR LV systolic function.…”

Cardiovascular imaging 2015 in the International Journal of Cardiovascular Imaging

“…Iron deficiency and cardiac sympathetic impairment play a role in the worsening of heart failure and these 2 conditions may be linked. nagao et al [11] evaluated 46 patients with dilated cardiomyopathy with both cardiac T2-Mri using a 3-T scanner for iron deficiency and (123)I-metaiodobenzylguanidine (MiBG) imaging for cardiac sympathetic activity. Myocardial T2 value (M-T2) was calculated by fitting signal intensity data for mid-left ventricular septum to a decay curve and (123)i-MiBG washout rate (MiBG-wr) was calculated using a polar-map technique with tomographic data.…”

“…rider et al found that myocardial tissue phase mapping reveals impaired myocardial tissue velocities in obesity [40]. The combination of cardiac T2* Mri and MiBG scintigraphy was a more powerful predictor of MACe than either parameter alone [41]. Zhang et al [42] showed that myocardial T2 mapping provides evidence for subclinical myocardial inflammation in patients with systemic lubus erthematosus.…”