With time, chronic bronchitis may lead to emphysema, i.e. overdistension of the alveoli.
Emphysema
This condition is due to a permanent and irreversible overdistension of the alveoli. It frequently
develops from chronic bronchitis as explained above. After years of overdistension, an
increasing proportion of the alveolar wall disintegrates with progressive obliteration of the
vascular bed of the lungs. This is the most common cause of right ventricular heart failure,
which, in itself, also causes breathlessness.
The main clinical features are breathlessness first on exertion and, with time, also at rest. In
severe cases the breathlessness is constant, the chest movements are limited, the breath sounds
inaudible and there may be cyanosis.
Emphysema can be clearly differentiated from asthma as the breathlessness is constant, whereas
in asthma, it comes in bouts. It can be differentiated from chronic bronchitis as there is no cough
nor abundant sputum.
The differentiation between asthma, chronic bronchitis and emphysema is important for
prognosis as the first two react well to acupuncture and herbal treatment, whilst emphysema less
so (Table 3.1Table 3.1).
Carcinoma of Bronchi
This is statistically the most common of all carcinomas and it accounts for 40% of all male
deaths from malignant disease.
The main clinical manifestations are a cough, with scanty sputum which may be blood-tinged,
chest pain and breathlessness, although this may appear only in quite late stages.
Causes in Heart
Left Heart Failure
When the left ventricle of the heart loses strength of contraction blood accumulates behind the
left ventricle in the pulmonary veins and lungs. The resulting pulmonary congestion reduces the
supply of oxygen to the alveoli and causes breathlessness.