Hemodynamic Characteristics in Chronic Obstructive Lung Disease as Related to Cardiac Size

Abstract

The hemodynamic adaptation during exercise was evaluated in 19 patients suffering from chronic obstructive lung disease. They were divided into two groups according to cardiac size on the X-ray (group 1, small; group 2, normal). A small cardio-thoracic ratio could be correlated with ‘emphysema’ assessed on the basis of hyperinflation and a low transfer test for CO. No clear-cut difference could be found between the two groups concerning the hemodynamic data at rest or during exercise. However, for all subjects, the cardiac output was found to be slightly related to the cardiac size (smaller cardiac output for smaller cardiac size). During exercise, a low cardiac output was characterized by a low oxygen transport and a high level of lactate. From this it is suggested that a small cardiac size, a classical feature of hyperinflation and emphysema, may lead to a low cardiac output. The explanation for these results is speculative, but variable hemodynamic profiles in chronic obstructive lung disease with or without hyperinflation may be related to the morphology of the cardiac chambers and to variable intrathoracic pressure regimes during respiration.

Hyperinflated lungs compress the heart during expiration in COPD patients: a new finding on dynamic-ventilation computed tomography

“…Although no previous publications have used dynamic-ventilation CT to observe heart size, “small heart in severe emphysema or COPD” has been observed in previous studies using different imaging modalities, including echocardiography, radiography, and magnetic resonance imaging (MRI). 9 – 11 , 15 , 32 , 33 The smaller heart size in patients with COPD is associated with lung hyperinflation. In patients with COPD, lung hyperinflation is caused by a decrease in the elastic recoil of the lung parenchyma and dynamic air trapping during successive breaths.…”

“… 14 – 16 , 34 Increased intrathoracic pressure decreases venous return to the heart, which decreases cardiac preload, and impairs the compliance of the intrathoracic vascular bed. 9 – 11 , 16 , 17 Furthermore, external compression from hyperinflated lungs increases end-diastolic pressure. 10 , 15 , 35 Consequently, cardiac size and function is compromised in patients with COPD and/or severe emphysema.…”

“… 6 – 8 Increased intrathoracic pressure reduces venous return and thus reduces right ventricular output. 9 – 13 Furthermore, hyperinflation is associated with reduced ventricular filling, reduced stroke volume, and lower cardiac output. 14 – 18 In addition, Watz et al 15 found that severe COPD is associated with smaller cardiac size on echocardiography.…”

Management of cardiovascular comorbidities in chronic obstructive pulmonary disease patients

“…The increase in the size of the lungs due to hyperinflation has a compression effect on the heart muscle, creating unfavorable conditions for its activity and hindering the implementation of its pumping function. A number of studies have shown that an increase in the severity of COPD and the appearance of emphysema are associated with a decrease in the size of the heart during X-ray examination (32)(33)(34). Almost 40 years ago, the term "microcardia" was widely used, and was considered a radiological sign of emphysema (33).…”

Chronic obstructive pulmonary disease and cardiovascular comorbidity

“…Увеличение размеров легких вследствие гипервоздушности оказывает компрессионное воздействие на сердечную мышцу, создавая неблагоприятные условия для ее деятельности и затрудняя осуществление ею насосной функции. В ряде исследований было показано, что повышение тяжести ХОБЛ и появление эмфиземы связано со снижением размеров сердца при рентгенологическом исследовании [33][34][35]. Почти 40 лет назад был широко распространен термин -микрокардия, который считался рентгенологическим признаком эмфиземы [34].…”