Comparing cardiac function and structure and their relationship with exercise capacity between patients with stable COPD and recent acute exacerbation: a cross-sectional study.

OBJECTIVE: Patients with COPD are prone to cardiac remodeling; however, little is known about cardiac function in patients recovering from an acute exacerbation of COPD (AECOPD) and its association with exercise capacity. The aim of this study was to evaluate the cardiac function and structure and to compare their relationship with exercise capacity in patients with a recent AECOPD and patients with clinically stable COPD. METHODS: This was a cross-sectional study including 40 COPD patients equally divided into two groups: recent AECOPD group (AEG) and clinically stable COPD group (STG). Echocardiography was performed to assess cardiac function and chamber structure. The six-minute walk distance (6MWD) and the Duke Activity Status Index (estimated Vo2) were used in order to assess exercise capacity. RESULTS: No significant differences in cardiac function and structure were found between the groups. The 6MWD was associated with early/late diastolic mitral filling velocity ratio (r = 0.50; p < 0.01), left ventricular posterior wall thickness (r = -0.33; p = 0.03), and right atrium volume index (r = -0.34; p = 0.04), whereas Vo2 was associated with right atrium volume index (r = -0.40; p = 0.02). CONCLUSIONS: Regardless of the clinical condition (recent AECOPD vs. stable COPD), the cardiac function and structure were similar between the groups, and exercise capacity (determined by the 6MWD and Vo2) was associated with cardiac features.

Comparing cardiac function and structure and their relationship with exercise capacity between patients with stable COPD and recent acute exacerbation: a cross-sectional study / Comparação da função e estrutura cardíaca e sua relação com a capacidade de exercício entre pacientes com DPOC estável e exacerbação aguda recente: estudo transversal

ABSTRACT Objective: Patients with COPD are prone to cardiac remodeling; however, little is known about cardiac function in patients recovering from an acute exacerbation of COPD (AECOPD) and its association with exercise capacity. The aim of this study was to evaluate the cardiac function and structure and to compare their relationship with exercise capacity in patients with a recent AECOPD and patients with clinically stable COPD. Methods: This was a cross-sectional study including 40 COPD patients equally divided into two groups: recent AECOPD group (AEG) and clinically stable COPD group (STG). Echocardiography was performed to assess cardiac function and chamber structure. The six-minute walk distance (6MWD) and the Duke Activity Status Index (estimated Vo2) were used in order to assess exercise capacity. Results: No significant differences in cardiac function and structure were found between the groups. The 6MWD was associated with early/late diastolic mitral filling velocity ratio (r = 0.50; p < 0.01), left ventricular posterior wall thickness (r = −0.33; p = 0.03), and right atrium volume index (r = −0.34; p = 0.04), whereas Vo2 was associated with right atrium volume index (r = −0.40; p = 0.02). Conclusions: Regardless of the clinical condition (recent AECOPD vs. stable COPD), the cardiac function and structure were similar between the groups, and exercise capacity (determined by the 6MWD and Vo2) was associated with cardiac features.

RESUMO Objetivo: Pacientes com DPOC são propensos a remodelamento cardíaco; no entanto, pouco se sabe sobre a função cardíaca em pacientes em recuperação de exacerbação aguda da DPOC (EADPOC) e sua associação com a capacidade de exercício. O objetivo deste estudo foi avaliar a função e estrutura cardíaca e comparar sua relação com a capacidade de exercício em pacientes com EADPOC recente e pacientes com DPOC clinicamente estável. Métodos: Estudo transversal com 40 pacientes com DPOC divididos igualmente em dois grupos: grupo EADPOC recente (GEA) e grupo DPOC clinicamente estável (GCE). Realizou-se ecocardiografia para avaliar a função cardíaca e a estrutura das câmaras. A distância percorrida no teste de caminhada de seis minutos (DTC6) e o Duke Activity Status Index (Vo2 estimado) foram utilizados para avaliar a capacidade de exercício. Resultados: Não foram encontradas diferenças significativas na função e estrutura cardíaca entre os grupos. A DTC6 apresentou associação com a razão entre as velocidades de enchimento diastólico mitral precoce e tardia (r = 0,50; p < 0,01), a espessura da parede posterior do ventrículo esquerdo (r = −0,33; p = 0,03) e o índice de volume do átrio direito (r = −0,34; p = 0,04), enquanto o Vo2 apresentou associação com o índice de volume do átrio direito (r = −0,40; p = 0,02). Conclusões: Independentemente da condição clínica (EADPOC recente vs. DPOC estável), a função e estrutura cardíaca eram semelhantes entre os grupos, e a capacidade de exercício (determinada pela DTC6 e pelo Vo2) apresentou associação com as características cardíacas.