IMPACTOS DO TABAGISMO NA MORFOFISIOLOGIA CARDIOPULMONAR E EFICIÊNCIA VENTILATÓRIA EM INDIVÍDUOS COM INSUFICIÊNCIA CARDÍACA

Abstract

BARBOSA, GWS. EFFECTS OF SMOKING ON CARDIOPULMONARY MORPHOPHYSIOLOGY AND VENTILATORY EFFICIENCY IN INDIVIDUALS WITH HEART FAILURE. Campo Grande - MS, 2022. [Doctoral Thesis - Federal University of Mato Grosso do Sul]. Smoking and heart failure (HF) alone affect the thoracic circulation, which can lead to micro- macrovascular disease. In addition, the presence of pulmonary emphysema (low attenuation area, LAA %) has been poorly studied in smoking associated with HF and without chronic obstructive pulmonary disease. Thus, microvascular disease and emphysema are important factors in ventilatory inefficiency, as both contribute for ventilation-perfusion inequality. Therefore, as a primary objective, we verified the original hypothesis that the ventilatory inefficiency, the degree of emphysema and vascular changes in the chest would be lower in a group of patients with HF never exposed to active smoking (Group 1), compared to a group of individuals with the same clinical-demographic characteristics, exposed to active smoking during their lifetime (Group 2). Additionally, the ventilatory efficiency was analyzed by a new method (ηV´E). As a secondary objective, we explored the correlations between vascular diameters for cross-sectional area of vessels less than 5mm (CSA<5mm) and the ratio between pulmonary artery and aorta diameter (PA/Ao) with Power(W) and peak oxygen consumption (V´O2), for the total group (n=34). Among other tests, both Group 1 (n=17) and Group 2 (n=17) performed complete spirometry, carbon monoxide diffusion test (DCO), high resolution chest computed tomography (HRCT) and cardiopulmonary exercise testing (CPET). As results, the groups were properly matched for clinical-demographic variables. Groups 1 and 2, respectively, did not show significant differences for ventilatory efficiency parameters (mean±SD), including the new method (ηV´E=10.1±2.9% and 10.3±2.7%, p=0.878). There was also no significant difference for microvascular diameter (CSA<5mm 0.5±0.1% and 0.7±0.3%, p=0.244), PA/Ao ratio (0.81±0.1 and 0.83±0.1, p=0.333) and LAA (1.3±06% and 2.6±5.6%, p=0.884). For the total group, the strongest correlations were between W%predicted (rho=0.760, p<0.001), V´O2%predicted (rho=0.745, p<0.001) and PA/Ao ratio (rho= - 0.470, p =0.008) with ηV'E. We conclude that smoking was not an additional adverse factor to deteriorate ventilatory efficiency, as the vascular structure studied and the quantification of emphysema by HRCT were not different between the groups. On the other hand, the new ventilatory efficiency index studied seems to be mechanistically more linked to aerobic performance and PA/Ao ratio, a promising indicator of pulmonary hypertension. Descriptors: Smoking, Heart failure, exercise.