Definition

Cor pulmonale is a term that describes the pathologic effects of lung dysfunction on the right side of the heart. The definition of cor pulmonale is right ventricular dilitation, with or without hypertrophy, caused by hypertension of the pulmonary circulation due to pulmonary dysfunction. Right sided (right ventricular) heart failure is a complication of cor pulmonale, not an essential feature of it. Excluded from the definition is pulmonary hypertension and right ventricular dysfunction due to left ventricular or congenital heart disease.

History

Symptoms: There are no specific symptoms for cor pulmonale. However, those conditions that are a consequence of cor pulmonale have symptoms that are widely variable and usually reflect the underlying pulmonary disorder or systemic venous congestion. Dyspnea at rest that is greatly exacerbated by exertion and not relieved by change in position, easy fatigability, productive and/or nonproductive cough, nonspecific chest pain, peripheral edema, upper abdominal fullness and tenderness, ascites, visible neck vein distention and wave fluctuations, and cyanosis may be present alone or in combination.

General:

Because the origins of pulmonary hypertension are so diverse, there is no history particularly specific for cor pulmonale. High suspicion of its presence should be assumed in any patient with pulmonary hypertension and/or any disorder causing chronic hypoxemia.

Age: Any.

Onset: Widely variable depending on cause of right ventricular dilatation/hypertrophy from pulmonary hypertension. May have acute, dramatic presentation as in the case of massive pulmonary emboli. Majority of cases, however, have slow, insidious development.

Duration: Dependent on chronicity of underlying cause of pulmonary hypertension. Intensity: Acute cor pulmonale has severe, catastrophic intensity as in the case of massive pulmonary embolus. In the remainder of cases, when cor pulmonale is present, it is tempting to measure its intensity as a function of the degree of venous congestion caused by right ventricular failure.

Aggravating Factors: Any factor that produces or deleteriously influences pulmonary hypertension (e.g., pulmonary emboli, chronic alveolar hypoxia, exercise, polycythemia, or high altitude).

Alleviating Factors: Any factor or condition that reduces pulmonary hypertension (e.g., lysis of pulmonary emboli, correction of chronic alveolar hypoxia, and so forth).

Physical Examination

General: Generally, physical stigmata of the underlying pulmonary disorder predominates (e.g., “blue bloater” of chronic bronchitis, “pink puffer” of the emphysemic), obesity, severe kyphoscoliosis, and inspiratory and expiratory adventitious sounds frequently present.

Cardiovascular:

In cor pulmonale with right ventricular CHF, distended neck veins that do not collapse with inspiration and prominent a and v waves may be observed.

Precordium: Check for sternal lift from right ventricular heave, palpable S2.

Auscultation: Evaluate left sternal border and/or epigastrium for right sided S3 gallop Sound. Note quality of S2 will be loud booming at times and P2 is intensified. Listen for systolic ejection click in pulmonic region, left of Upper sternum. Note any murmurs, frequently heard is the holosystolic murmur of tricuspid regurgitation located at the lower left parasternal edge that is accentuated by inspiration. Rarely, a diastolic murmur of pulmonary valve regurgitation will be heard.

Extremities: In acute cor pulmonale from pulmonary emboli the patient may have evidence of deep venous thrombosis, phlebitis frequently present. In cor pulmonale with right ventricular CHF, peripheral edema may be seen.

Gastrointestinal: In cor pulmonale with right ventricular CHF hepatomegaly (occasionally pulsatile, usually tender) or ascites may be present.

Pulmonary: In acute Cor pulmonale from pulmonary emboli the patient may not have stigmata of COPD. Appearance, in that case, is one of severe anxiety, breathlessness, pallor, diaphoresis, hypotension, rapid and thready pulse, near collapse.

Skin: In cor pulmonale with right ventricular CHF, cyanosis may be evident.

Pathophysiology

Increased pulmonary vascular resistance and pulmonary hypertension caused by pathologic conditions of the lung parenchyma and / or pulmonary vasculature producing increased afterload on the right ventricle causing ventricular with or without hypertrophy.

Cor pulmonale can be the result an acute or chronic condition Acute cor pulmonale is a result of large or multiple emboli causing sudden, massive obstruction of the pulmonary circulation. Chronic corulmonale is a result of numerous long term conditions with diverse Pathophysiologic characteristics but with the common end result of producing pulmonary hypertension. For simplicity, these conditions can be separated into those that affect pulmonary vasculature and those that are (primarily) respiratory diseases. The following are examples (not all inclusive):

Pulmonary vasculature: Chronic, small pulmonary emboli; sickle cell thrombosis; primary pulmonary hypertension; adult respiratory distress syndrome; toxic or particulate intravenous drug use collagen vascular disorders; granulomatous arteritis.

Respiratory diseases: Chronic obstructive pulmonary disease such as chronic bronchitis, emphysema, and cystic fibrosis. Chronic hypoventilation conditions such as severe obesity, sleep apnea syndrome, and neuromuscular weakness. Chest wall abnormalities (e.g., kyphoscoliosis). Diffuse interstitial diseases such as sarcoid, idiopathic pulmonary fibrosis, and chronic fungal infections. And unusual conditions such as high altitude disease (chronic mountain sickness), pulmonary resection, encroaching mediastinal tumor, and radiation.

Diagnostic Studies

Due to the diverse pathophysiologic conditions that may lead to pulmonary hypertension and cor pulmonale, the character of diagnostic studies will vary greatly. Each condition will display laboratory, radiographic, and other diagnostic study results unique to its pathologic cause and effect. Because cor pulmonale is a secondary condition of a primary disorder, careful consideration of those entities that can lead to pulmonary hypertension is essential.

Regardless of causative condition, primary diagnostic evidence suggesting the presence of cor pulmonale may include the following.

Radiology

CXR: Right ventricular enlargement and filling of retrostemal space on lateral view, enlargement of main pulmonary artery and major branches, right greater than 16 mm diameter, pruned (narrowed) peripheral arterial vessels.

ECG: Frequently normal. Presence of the so called “P pulmonale,” tall peaked P waves, particularly in inferior leads (II, III, AVF) and VI; QRS right axis deviation frequently coupled with prominent R in V1 to V3 deep S in V6 S-T depression, T inversion in precordial leads. ECG: Right ventricular dilatation and/or hypertrophy. First pass multiple gated acquisition scan (MUGA): Reduced right ventricular ejection fraction.

Thallium 201 scan: Free wall thickening of the right ventricle.

Right heart catheterization: Elevated pulmonary artery pressures and vascular resistance, normal pulmonary capillary wedge pressure (PCWP) and wide difference between pulmonary artery diastolic and PCWP.

Differential Diagnosis

Cor pulmonale is unique in that it is a distinct anatomic condition (right ventricular dilatation and/or hypertrophy) resulting from pulmonary hypertension caused by numerous and diverse disorders of the pulmonary system. The end result of cor pulmonale may be the production of the signs and symptoms of circulatory congestion commonly known as CHE Differential diagnosis, then, becomes a matter of detennining the origin of the symptoms of circulatory congestion (e.g., right heart failure versus left heart failure) remembering that right ventricular dysfunction is a result of left ventricular dysfunction or congenital heart disease is excluded from the definition of cor pulmonale. In summation, deduction of primary right ventricular failure as a result of cor pulmonale requires the concurrence of historical, physical, and diagnostic data that implicates right ventricular dysfunction as a result of disease states that produce pulmonary parenchymal or vasculature abnormalities.

Treatment

Treatment is directed at improving the pulmonary disorder so as to decrease pulmonary hypertension and managing right ventricular CHF Vigorous and aggressive management of the underlying pulmonary disease is required. Oxygen therapy is essential, long term and continuous, so as to reduce hypoxic pulmonary vasoconstriction. This is in addition to any therapeutic measures to improve concomitant pulmonary or systemic disease such as bronchodilators, antibiotics, pulmonary toilet, corticosteroids, discontinuance and/or avoidance of respiratory irritants, weight reduction, etc. Circulatory congestion caused by right ventricular failure is managed with the therapeutic modalities used in the treatment of any form of CHF: ensuring treatment compliance, reducing sodium intake and exertional stress, weight reduction (if needed), initiation of diuretic therapy and so forth. The use of digitalis and vasodilator therapy may be considered, although controversy remains over their long-term efficacy in right ventricular failure. In conditions causing polycythemia, phlebotomy to reduce red blood cell mass to less than 55 percent should be considered.

Pediatric Considerations

Cystic fibrosis and primary pulmonary hypertension are the major pulmonary disorders leading to cor pulmonale in the pediatric age group.

Pulmonary hypertension in children is often associated with congenital heart disease and therefore must be carefully ruled out as a potential cause. Pulmonary hypertension secondary to a congenital heart defect rarely persists if surgically corrected prior to 2 years of age. Occasionally, children develop pulmonary hypertension without a known etiology (idiopathic pulmonary hypertension). Management of children with idiopathic pulmonary hypertension primarily involves symptomatic treatment. These children develop polycythemia, CHF and arrhythmias, and require treatment for these conditions as well. I diopathic pulmonary hypertension is progressive and irreversible. It will generally have a fatal outcome within one year of diagnosis.

Obstetrical Considerations

In a patient with pre-existing kyphoscoliotic heart disease, cor pulmonale can develop if the patient becomes pregnant.

Tagged under:artery Cardiology cor pulmonale heart failure hypertension polycythemia ventricular

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