Exercise and myocardial injury in hypertrophic cardiomyopathy

Abstract

ObjectiveTroponin and high signal intensity on T2-weighted (HighT2) cardiovascular magnetic resonance imaging (CMRi) are both markers of myocardial injury in hypertrophic cardiomyopathy (HCM). The interplay between exercise and disease development remains uncertain in HCM. We sought to assess the occurrence of postexercise troponin rises and its determinants.MethodsMulticentre project on patients with HCM and mutation carriers without hypertrophy (controls). Participants performed a symptom limited bicycle test with hs-cTnT assessment pre-exercise and 6 hours postexercise. Pre-exercise CMRi was performed in patients with HCM to assess measures of hypertrophy and myocardial injury. Depending on baseline troponin (< or >13 ng/L), a rise was defined as a >50% or >20% increase, respectively.ResultsTroponin rises occurred in 18% (23/127) of patients with HCM and 4% (2/53) in mutation carriers (p=0.01). Comparing patients with HCM with and without a postexercise troponin rise, maximum heart rates (157±19 vs 143±23, p=0.004) and maximal wall thickness (20 mm vs 17 mm, p=0.023) were higher in the former, as was the presence of late gadolinium enhancement (85% vs 57%, p=0.02). HighT2 was seen in 65% (13/20) and 19% (15/79), respectively (p<0.001). HighT2 was the only independent predictor of troponin rise (adjusted odds ratio 7.9; 95% CI 2.7 to 23.3; p<0.001).ConclusionsPostexercise troponin rises were seen in about 20% of patients with HCM, almost five times more frequent than in mutation carriers. HighT2 on CMRi may identify a group of particularly vulnerable patients, supporting the concept that HighT2 reflects an active disease state, prone to additional injury after a short episode of high oxygen demand.

Usefulness of High-Sensitivity Cardiac Troponin T to Predict Long-Term Outcome in Patients with Hypertrophic Cardiomyopathy

“…Possible modalities to improve risk stratification are CMR imaging techniques such as LGE, T1-and T2-weighted mapping techniques, but also easily available and patientfriendly serum biomarkers may be attractive. 3,4,11 In this report, we confirm the independent association of an elevated hs-cTnT with long-term adverse outcome in HC, 6 and the majority of events was related to HF rather than to ventricular arrhythmias. For hs-cTnT as a continuous variable, we also demonstrated a significant association with clinical outcome in univariate analysis, while in multivariate analysis statistical significance was no longer present (p = 0.096), which might be related to limited cohort size and event rate.…”

“…As the primary focus of our project was on biomarkers, MRI and exercise, collection of these data was protocol driven, and echocardiography was not. 11 We acknowledge that echocardiographic parameters on diastolic function could be promising for event prediction. In that regard, in future studies it may be considered to include a protocol-driven echocardiographic work-up to assess the potential of these variables.…”

“…From a Dutch HC multicenter study on biomarkers, MRI and exercise, we selected HC patients of whom baseline hs-cTnT concentration was available. 11 In short, adult HC patients from different hospitals were enrolled at 2 outpatient clinics (Radboud University Medical Center, Nijmegen and Albert Schweitzer Hospital, Dordrecht, The Netherlands) between 2008 and 2014. Patients had to fulfill the diagnostic criteria for HC according to the prevailing guidelines and had no history of coronary artery disease or septal reduction therapy.…”

The Time Has Come to Explore Plasma Biomarkers in Genetic Cardiomyopathies

“…This suggests an association of these biomarkers with hypertrophy development. Exercise strongly increased plasma BNP and cTn levels in HCM patients, suggesting that the combination with exercise could have a stronger discriminatory effect [ 73 , 74 ]. Interestingly, it was shown that exercise increased BNP plasma levels particularly in HCM patients with silent ischemia [ 75 ].…”

The Impact of Ischemia Assessed by Magnetic Resonance on Functional, Arrhythmic, and Imaging Features of Hypertrophic Cardiomyopathy

“…Myocardial edema evaluated by T2-weighted imaging has been described in patients with HCM, associated with signs of advanced disease, such as higher LV mass, lower ejection fraction, and greater LGE extent (32). Furthermore, high T2 was associated with postexercise troponin rise in patients with HCM, identifying a subset of individuals more vulnerable to myocardial injury after a situation of high oxygen demand (33). In our cohort, ischemia had a weak evidence of association with higher T2 values, whereas non-obstructive HCM was associated with lower T2 compared to obstructive HCM.…”