Cardiac MRI-derived T2 mapping may help heart failure patients

Researchers used T2 mapping taken from weekly cardiac MRIs to help identify cardiotoxicity at an early stage, according to results of a pig study published Feb. 18 in the Journal of the American College of Cardiology. The findings could help cancer patients at risk of chemo-induced heart failure.

In the study, Carlos Galan-Arriola, DVM, with the National Center for Cardiovascular Research in Madrid, and colleagues sought to identify early serial cardiac magnetic resonance (CMR) markers of anthracycline-induced cardiotoxicity. Anthracycline is a popular class of chemotherapy drug and contributes to heart failure in up to 25 percent of patients.

Galan-Arriola studied 15 pigs which were administered either three or five biweekly intracoronary doxorubicin doses and followed with CMR exams performed every week for up to 16 weeks. A group of five pigs that didn’t receive the drug were used as controls.

The group found that T2 relaxation time increased significantly starting at six weeks in pigs receiving doxorubicin before left ventricular ejection fraction (LVEF) began declining at week nine. Five pigs whose anthracycline was stopped after the T2 changes showed those times returned to normal prior to week 16 with LVEF never worsening.

“The identification of T2 relaxation-time prolongation as a very early marker of reversible intracardiomyocyte vacuolization thus has important clinical implications,” the authors wrote. “Serial T2 mapping might allow tailored anthracycline dose management, with patients showing no T2 mapping abnormalities perhaps able to receive further doses, even beyond currently accepted high cardiotoxicity limits, without increasing the risk of future LV dysfunction.”