Reply T1 and T2 Mapping in Nonischemic Cardiomyopathies and Agreement With Endomyocardial Biopsy

With great interest we read Drs. Puntmann and Nagel ’s observations and interpretation of the results of the MyoRacer (Comprehensive Cardiac Magnetic Resonance Imaging in Patients With Suspected Myocarditis) trial(1), which highlight a couple of important considerations in this field. Cardiac magnetic resonance findings are believed to depend on the severity of myocarditis and the time imaging is performed along the course of disease. We(2) and the Puntmann group(3) have therefore grouped patients according to symptoms, presuming that this will result in a more acute and a more chronic myocarditis cohort. The study by Hinojar et  al.(3) compared patients with acute versus convalescent myocarditis and we agree with their interpretation of decreasing T1 values with less inflammation over time. However, without data of endomyocardial biopsies, the true disease entity of patients will always remain speculative. This together with differences in clinical presentation —predominantly infarct-like(3) versus heart failure –like myocarditis(1)—and symptom duration in the chronic populations—average of 6 months(3) versus 30 days(1)—limit meaningful comparisons between studies. As pointed out by Puntmann and Nagel, the comparable T2 values of patients with acute versus chronic myocarditis in the MyoRacer trial suggest that levels of inflammation might have been too similar to detect significant differences in T2 values. Howe ver, the acute and chronic group of the MyoRacer ...

Source: Journal of the American College of Cardiology - October 18, 2016 Category: Cardiology Source Type: research