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

Sílvia Aguiar Rosa; Boban Thomas; António Fiarresga; Ana Luísa Papoila; Marta Alves; Ricardo Pereira; Gonçalo Branco; Inês Cruz; Pedro Rio; Luis Baquero; Rui Cruz Ferreira; Miguel Mota Carmo; Luís Rocha Lopes

doi:10.3389/fcvm.2021.761860

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

Front Cardiovasc Med. 2021 Dec 17:8:761860. doi: 10.3389/fcvm.2021.761860. eCollection 2021.

Authors

Sílvia Aguiar Rosa^{1

2

3}, Boban Thomas³, António Fiarresga¹, Ana Luísa Papoila^{2

4}, Marta Alves^{2

4}, Ricardo Pereira³, Gonçalo Branco³, Inês Cruz⁵, Pedro Rio¹, Luis Baquero³, Rui Cruz Ferreira¹, Miguel Mota Carmo², Luís Rocha Lopes^{6

7

8}

Affiliations

¹ Department of Cardiology, Santa Marta Hospital, Lisbon, Portugal.
² NOVA Medical School, Faculty of Medical Science of Lisbon, New University, Lisbon, Portugal.
³ Heart Centre, Hospital Cruz Vermelha Portuguesa, Lisbon, Portugal.
⁴ Epidemiology and Statistics Unit, Research Centre, Centro Hospitalar Universitário de Lisboa Central and Centre of Statistics and its Applications, University of Lisbon, Lisbon, Portugal.
⁵ Department of Cardiology, Hospital Garcia de Orta, Almada, Portugal.
⁶ Inherited Cardiac Disease Unit, Bart's Heart Centre, St Bartholomew's Hospital, London, United Kingdom.
⁷ Centre for Heart Muscle Disease, Institute of Cardiovascular Science, University College London, London, United Kingdom.
⁸ Cardiovascular Centre, University of Lisbon, Lisbon, Portugal.

Abstract

Aims: The aim of the study is to investigate the association between the degree of ischemia due to coronary microvascular dysfunction (CMD) and the left ventricular (LV) tissue characteristics, systolic performance, and clinical manifestations in hypertrophic cardiomyopathy (HCM). Methods and Results: This prospective study enrolled 75 patients with HCM without obstructive epicardial coronary artery disease. Each patient underwent cardiovascular magnetic resonance (CMR) including parametric mapping, perfusion imaging during regadenoson-induced hyperemia, late gadolinium enhancement (LGE) and three-dimensional longitudinal, circumferential, and radial strains analysis. Electrocardiogram, 24-h Holter recording, and cardiopulmonary exercise testing (CPET) were performed to assess arrhythmias and functional capacity. In total, 47 (63%) patients were men with the mean age of 54.6 (14.8) years, 51 (68%) patients had non-obstructive HCM, maximum wall thickness (MWT) was 20.2 (4.6) mm, LV ejection fraction (LVEF) was 71.6 (8.3%), and ischemic burden was 22.5 (16.9%) of LV. Greater MWT was associated with the severity of ischemia (β-estimate:1.353, 95% CI:0.182; 2.523, p = 0.024). Ischemic burden was strongly associated with higher values of native T1 (β-estimate:9.018, 95% CI:4.721; 13.315, p < 0.001). The association between ischemia and LGE was significant in following subgroup analyses: MWT 15-20 mm (β-estimate:1.941, 95% CI:0.738; 3.143, p = 0.002), non-obstructive HCM (β-estimate:1.471, 95% CI:0.258; 2.683, p = 0.019), women (β-estimate:1.957, 95% CI:0.423; 3.492, p = 0.015) and age <40 years (β-estimate:4.874, 95% CI:1.155; 8.594, p = 0.016). Ischemia in ≥21% of LV was associated with LGE >15% (AUC 0.766, sensitivity 0.724, specificity 0.659). Ischemia was also associated with atrial fibrillation or flutter (AF/AFL) (OR-estimate:1.481, 95% CI:1.020; 2.152, p = 0.039), but no association was seen for non-sustained ventricular tachycardia. Ischemia was associated with shorter time to anaerobic threshold (β-estimate: -0.442, 95% CI: -0.860; -0.023, p = 0.039). Conclusion: In HCM, ischemia associates with morphological markers of severity of disease, fibrosis, arrhythmia, and functional capacity.

Keywords: arrhythmia; cardiovascular magnetic resonance; coronary microvascular dysfunction; functional capacity; hypertrophic cardiomyopathy; tissue characteristics.