Blunted coronary flow velocity reserve is associated with impairment in systolic function and functional capacity in hypertrophic cardiomyopathy. (15th July 2022)

• Record Type: Journal Article
• Authors: Aguiar Rosa, Sílvia; Lopes, Luís Rocha; Branco, Luísa; Galrinho, Ana; Fiarresga, António; Thomas, Boban; Brás, Pedro; Gonçalves, António; Cardoso, Isabel; Papoila, Ana; Alves, Marta; Rio, Pedro; Cruz, Inês; Selas, Mafalda; Silva, Filipa; Silva, Ana; Ferreira, Rui Cruz; Carmo, Miguel Mota
• Is Part Of: International journal of cardiology. Volume 359(2022)
• Page Start: 61
• Page End: 68
• Publication Date: 2022-07-15
• Subjects: Hypertrophic cardiomyopathy -- Coronary flow velocity reserve -- Ventricular function, functional capacity -- Echocardiography -- Cardiopulmonary exercise testing; Cardiology -- Periodicals; Electronic journals; 616.12
• DOI: 10.1016/j.ijcard.2022.04.032
• Languages: English
• ISSNs: 0167-5273

Abstract

Abstract: Background: Coronary microvascular dysfunction constitutes an important pathophysiological feature in hypertrophic cardiomyopathy (HCM). We aimed to assess the association between impaired coronary flow velocity reserve (CFVR) and ventricular systolic function and functional capacity. Methods: Eighty-three patients with HCM were enrolled in this prospective cohort study. Patients underwent echocardiogram to evaluate ventricular performance and CFVR in the left anterior descending artery (LAD) and posterior descending artery (PD). Diastolic coronary flow velocity was measured in basal conditions and in hyperemia. CFVR was calculated as the ratio of hyperemic and basal peak diastolic flow velocities. Functional capacity was evaluated by cardiopulmonary exercise testing (CPET). The link between CFVR and biventricular systolic function and peak VO2 was studied. Results: Age was 55.0(14.4)years, 50 patients (60%) were male; 59 patients (71%) had nonobstructive HCM. Mean CFVR LAD was 1.81(0.49) and CFVR PD was 1.73(0.55). Lower CFVR PD was associated with impaired global longitudinal strain (GLS) 2D (β-estimate:-3.240, 95%CI:-4.634;-1.846, p < 0.001), GLS 3D (β-estimate:-2.559, 95%CI:-3.932;-1.186, p < 0.001) and area strain (β-estimate:-3.044, 95%CI:-5.373;-0.716, p = 0.011). Lower values of CFVR PD related to worse global work index (β-estimate:267.824, 95%CI:75.964;459.683, p = 0.007), global constructive work (β-estimate:217.300, 95%CI:38.750;395.850, p = 0.018) and global work efficiency (β-estimate:5.656, 95%CI:2.229;9.084, p = 0.002). Impaired CFVR LAD (β-estimate:2.826, 95%CI:0.913;4.739, p = 0.004) and CFVR PD (β-estimate:2.801, 95%CI:0.657;4.945, p = 0.011) were associated with lower TAPSE. Lower values of CFVR LAD (β-estimate:2.580, 95%CI:0.169;4.991, p = 0.036) and CFVR PD (β-estimate:3.163, 95%CI: 0.721;5.606, p = 0.012) were associated with worse peak VO2 . Conclusion: Lower CFVR was associated with impairment in biventricular systolic function parameters and functional capacity assessed by pVO2 . Highlights: Impaired CFVR is a frequent echocardiographic finding in patients with HCM. Lower CFVR is related to impaired left ventricular myocardial deformation parameters. Blunted CFVR is associated with shorter tricuspid annular plane systolic excursion. Lower CFVR is linked to worse functional capacity, assessed by peak oxygen uptake. Ischemia in 18% of LV by CMR was associated with CFVR <2.0 in the echocardiogram.