Pulmonary Heart Disease (Cor Pulmonale) – Causes, Symptoms, Diagnosis And Treatment
Pulmonary Heart Disease
Pulmonary heart disease is defined as a dilation of the right ventricle, with or without right ventricular hypertrophy produced due to pulmonary diseases, from vascular or parenchymatous nature.
Pulmonary Heart Disease Causes
- The main causes of acute pulmonary heart disease are: pulmonary embolism, which interest more than 50% of the pulmonary vascular network.
- Chronic pulmonary heart disease of parenchymal nature cause are: chronic obstructive pulmonary disease (COPD), pulmonary fibrosis, large pleural fibrosis (post-tuberculosis, the most common), cifo-scoliosis, morbid obesity, sleep apnea, polycythemia vera.
- Chronic pulmonary heart disease of vascular nature cause are: recurrent pulmonary embolism and primary pulmonary hypertension.
Pulmonary Heart Disease Classification
After the rapidity of installation, pulmonary heart disease is classified as acute pulmonary heart disease and chronic pulmonary heart disease. In its turn, chronic pulmonary heart disease is classified as follows :
According to the type of lung disease:
- Chronic pulmonary heart disease of vascular nature;
- Chronic pulmonary heart disease of parenchymal nature.
After the absence or presence of signs of right heart failure:
- Compensated chronic pulmonary heart disease;
- Decompensated chronic pulmonary heart disease.
The link between lung disease and heart disease is represented by pulmonary hypertension, defined by pulmonary arterial systolic pressure values over 30 mmHg (normal 22-30 mmHg) and mean pulmonary arterial pressure over 20 mmHg (normal 13 -18 mmHg). Pulmonary hypertension results from the following mechanisms:
- Pulmonary arterial vasoconstriction, caused by hypoxia;
- Increased blood viscosity;
- Thickening, with lumen reduction of pulmonary vessels.
Pulmonary Heart Disease Symptoms
Clinical manifestations are nonspecific for pulmonary heart disease. They differ in acute pulmonary heart disease from chronic pulmonary heart disease.
Acute pulmonary heart disease
The onset of acute pulmonary heart disease is suddenly and can occur in the suggestive context of thrombophlebitis of the lower limbs. Nonspecific symptoms are:
- Extremely severe polipnea, without changes in physical examination;
- Unexplained anxiety;
- Chest pain;
Physical examination may reveal:
- Skin changes: cyanosis, pallor, sweating;
- Signs of cerebral hypoperfusion: agitation, confusion and even coma;
- Tachycardia, gallop rhythm of the right ventricle,systolic murmur of tricuspid regurgitation;
- Signs of decompensation of the right ventricle: jugular turgor, hepatomegaly, often painful, hepato-jugular reflux, lower limb edema.
Chronic pulmonary heart disease:
Onset is insidious, clinical manifestations are dominated by the respiratory disease.
Symptoms are also nonspecific: dyspnea, fatigue, chest pain, cough, hemoptysis and in severe forms, dysphonia.
Physical examination may reveal:
- Mixed type of skin cyanosis, sometimes jaundice;
- Changes in cardiac examination: left parasternal impulse given by right ventricular hypertrophy, tachycardia, atrial or ventricular gallop, right systolic murmur of tricuspid regurgitation, systolic ejection murmur at pulmonary focus, diastolic murmur of pulmonary regurgitation.
- Signs of decompensation of the right ventricle: jugular turgor, hepatomegaly, hepato-jugular reflux, edema.
Chest radiography may reveal:
- Increased transverse diameter of heart;
- Increased inferior branches of pulmonary artery;
- Specific changes that caused pulmonary heart disease.
ECG shows the following changes:
- In acute pulmonary heart disease: right axial deviation, complete or incomplete right bundle branch block, sinus tachycardia, reversal of T waves in right chest leads.
- In chronic pulmonary heart disease: right ventricular hypertrophy, right bundle branch block, P wave of pulmonary type, sinus tachycardia, atrial or ventricular arrhythmias.
Two-dimensional echocardiography shows the existence of the right ventricle dilatation. Doppler ultrasound allows measurement of systolic pressure of pulmonary artery and will confirm the pulmonary or tricuspid regurgitation.
- Increased hematocrit and hemoglobin (secondary to chronic hypoxia or polycythemia vera);
- Changes in blood gases: decreased oxygen partial pressure, carbon dioxide partial pressure is normal or decreased.
Other tests: respiratory function tests, pulmonary ventilation and perfusion scintigraphy, right heart catheterization, pulmonary angiography, chest CT.
Positive diagnosis is established on history, clinical signs and paraclinical investigations. It is often uncertain for acute pulmonary heart disease.
Pulmonary Heart Disease Evolution And Prognosis
In acute pulmonary heart disease, short-term prognosis is reserved. Mortality exceeds 25%, death occurring usually within 2 hours after pulmonary embolism. Those who survive this period, will develop cardiogenic shock in the next period. If this period is also exceeded, the evolution is favorable, the recovery is, most often, complete. But there is the risk of pulmonary embolism recurrence and the risk of development of chronic pulmonary heart disease in time.
In chronic pulmonary heart disease, evolution is long, slow and progressive. On this background there is a possibility of decompensation caused by hypoxia, consecutive to intercurrent respiratory infections. Over-addition of atrial fibrillation or atrial flutter, aggravates the prognosis.
Pulmonary Heart Disease Treatment
Acute pulmonary heart disease:
- Supportive measures: oxygen therapy, on the tube or mask, appropriate parenteral hydration, inotropic support to maintain blood pressure over 90 mmHg.
- Anti-coagulation treatment is designed to prevent the increasing in size of the emboli. In the absence of contraindications, anti-coagulation therapy should be started even if the diagnosis is uncertain, but is likely. It begins with heparin or fractionated heparin, according to known protocols. The heparin treatment is continued with oral anticoagulants administered so that INR is maintained between 2 and 3.
- Thrombolytic therapy is designed to dissolve the blood clots. It is established in patients with pulmonary embolism who have signs of hemodynamic instability, being more efficient if is given earlier.
- Surgical embolectomy or catheter suctioning of the emboli is a last resort solution, in patients who continue to deteriorate despite conservative treatment which is properly administered.
Chronic pulmonary heart disease:
Treatment is aimed, primarily, to solve the lung disease that is generating the chronic pulmonary heart disease (COPD, pulmonary embolism). Improved lung function leads, by increasing the oxygen partial pressure, to lower pulmonary artery pressure.
Diuretics are used for fluid retention. These drugs are administered only after the improvement of respiratory function. Caution must be employed to avoid electrolyte disturbance which, in conditions of hypoxia, can lead to severe ventricular arrhythmias.
Digoxin is not indicated in case of sinus rhythm, because it has no positive inotropic effect on the right ventricle and may promote ventricular arrhythmias. It is recommended for heart rate control, in case of atrial fibrillation.
Other therapeutic methods are the vasodilatory medications (calcium channel blockers, prostacyclin, endothelin receptor antagonists), chronic anticoagulation therapy (in chronic pulmonary heart disease of vascular nature), provoked bleeding (300-400 ml) if the hematocrit is above 55% and lung transplantation.