Contribution of 2 D strain in the detection of subtle myocardial involvement in group A and B patients with chronic obstructive pulmonary disease.

Abstract

Background: Myocardial involvement mediated by chronic obstructive pulmonary disease (COPD) is a common cause of morbidity and mortality. Conventional transthoracic echocardiography (TTE) parameters are poor in the detection of subclinical myocardial dysfunction.

Aim: To investigate the contribution of strain in the early detection of cardiac damage in clinically stable COPD patients.

Methods: This was a comparative study between COPD patients (classified A or B) with normal and reduced right ventricle (RV) strain. The COPD assessment test (e.g., CAT score), spirometry [e.g., forced expiratory volume in 1 s (FEV₁, L)], 6 min walk test [e.g., 6 min walk distance (6MWD, m)], and both conventional TTE [i.e., left ventricular ejection fraction (LVEF), right atrium (RA), RV, left ventricle global longitudinal strain (LV GLS)], and strain (e.g., impaired RV strain is > -19), were performed.

Results: Eighty COPD patients [mean ± standard deviation (SD): age = 66 ± 9 years, LVEF = 60.1 ± 5%, RA = 25 ± 7%, RV = -19.9 ± 3.7%, LV GLS v -21.1 ± 2, and 48% had impaired RV strain] were included. Compared to COPD patient with normal RV strain, those with reduced RV strain had (i) Lower 6MWD (310 ± 113 vs 470 ± 104 m; p = 0.001), (ii) Lower FEV₁ (1.63 ± 0.73 vs 2.18 ± 0.41 L; p = 0.012), and (iii) Higher CAT score (21 ± 10 vs 13 ± 6; p = 0.012). An impaired RV strain was associated with a higher risk of hospitalizations for acute exacerbation in the post inclusion year, (respectively for 55% and 25%; p = 0.024). No death was recorded during the study period.

Conclusion: Group A and B COPD patients having normal conventional TTE parameters, speckle tracking is a key parameter in the detection of subclinical myocardial dysfunction.