Cor Pulmonale

Cor Pulmonale is the failure of the right side of the heart caused by prolonged high blood pressure in the pulmonary artery and right ventricle of the heart. Any condition that leads to prolonged high blood pressure in the arteries or veins of the lungs causes a condition called Pulmonary Hypertension. This Pulmonary Hypertension hinders the right ventricle function and thus, the heart fails to pump against these abnormally high pressures leading to Cor Pulmonale. Chronic lung diseases like COPD or other conditions like Obstructive Sleep Apnea, Central Sleep Apnea and Cystic Fibrosis causing prolonged low blood oxygen can also lead to Cor Pulmonale. The symptoms include shortness of breath, wheezing, coughing, swelling of the feet or ankles, exercise intolerance, chest discomfort, cyanosis, distension of the neck veins indicating high right-heart pressures, abnormal fluid collection in the abdomen, enlargement of the liver and abnormal heart sounds. Cor Pulmonale can lead to right-heart failure and death. Preliminary investigation includes Chest X ray, Electro Cardiogram and Echo Cardiogram. Elimination of the cause is the most important intervention. 

Incidence

About 62 percent of patients suffering from chronic pulmonary diseases including COPD have been found to be affected by Cor Pulmonale with an average duration of 5.16 years (Krishnaswami et.al, 1980). Acute Cor Pulmonale is a frequent and lethal complication of Acute Respiratory Distress Syndrome (Baron et.al, 2001). A retrospective clinical study to examine the incidence of Acute Cor Pulmonale in massive Pulmonary Embolism, diagnosed on the basis of Transthoracic Echocardiographic criteria in one hundred and sixty-one patients with massive Pulmonary Embolism has shown incidence of Acute Cor Pulmonale in sixty one percent of the sample with massive Pulmonary Embolism with twenty three percent mortality rate (Baron et.al, 2001). Schistosomiasis is the third leading endemic parasitic disease in the world (Salama et.al, 2003). Eleven to thirty three percent incidence of Schistosomal Cor Pulmonale has been reported at autopsy in urinary or intestinal Schistosomiasis cases (Andrade et.al, 1970; Sadigursky et.al, 1982). Pulmonary Embolus can manifest as Acute Cor Pulmonale due to massive embolus obstructing nearly sixty to seventy five percent of the pulmonary circulation. Cor Pulmonale has also been diagnosed in patients with Pulmonary Tuberculosis (Kapoor, 1959).

Although right-heart overload is rare in Sarcoidosis, clinical and Electrocardiographic features of Cor Pulmonale have been reported in twenty eight percent patients in a sample of twenty one. An invasion of the walls of pulmonary vessels by sarcoid granulomas or their compression by the fibrotic process seems to the cause of Car Pulmonale. Pathological studies have revealed compression of large pulmonary arteries associated with specific sarcoid lesions in small and medium-sized arteries (Battesti et.al, 1978).A higher incidence ofCor Pulmonale exists in the pediatric age group and approximately half the patients with Cor Pulmonale have terminal decompensation and die in severe right-sided cardiac failure (Royce, 1951). Tumor embolization has been found at autopsy in the pulmonary arteries of 33 of 331 patients dying with primary carcinoma of the lung with venous or lymphatic vascular involvement.

Enlargement of the right cardiac ventricle has been reported in 26 of the 33 cases with Dyspnea as the initial symptom or one of the major symptoms taking us to the conclusion that pulmonary arterial embolization is a relatively frequent complication of primary lung Carcinoma, particularly Adenocarcinoma, which leads to the development of Pulmonary Hypertension and Cor Pulmonale (Vitale et.al, 2006). Cor Pulmonale and heart failure in association with chronic upper airway obstruction have been reported in Down Syndrome infants with features of Sleep Apnea like noisy breathing with Retraction, Cyanosis, Daytime lethargy and Somnolence (Levine and Simpser, 1982). However, the most frequent cause of Cor Pulmonale can be attributed to chronic obstructive pulmonary disease (COPD) due to Chronic Bronchitis or Emphysema (MacNee et.al, 1994; Wiedemann et.al, 1990; Salvaterra et.al, 1993).

Evaluation

Diagnosis of Cor Pulmonale is often difficult due to the fact that Pulmonary Vascular Disease, Pulmonary Hypertension and Cor Pulmonale have few specific manifestations, especially in their early stages (Palevsky and A. P. Fishman, 1990). Right heart catheterization is the most accurate but invasive test to confirm the diagnosis of Cor Pulmonale and gives important information regarding the underlying diseases. Arterial Blood Gas Values, Laboratory Tests, Electrocardiograms, Chest X-Ray, Echocardiography and Radionuclide Angiography are useful in evaluation of Cor Pulmonale (Sofer et.al, 1988). Echocardiography is an alternative procedure to right heart catheterization (Baron et.al, 2002). Laboratory investigations include Hematocrit for Polycythemia which can increase pulmonary arterial pressure by increasing viscosity, serum alpha1-antitrypsin and antinuclear antibody level for collagen vascular disease such as Scleroderma. Hypercoagulability is evaluated by serum levels of proteins S and C, Antithrombin III, Anticardiolipin antibodies, and Homocysteine (Klinger et.al, 2005).

Arterial Blood Gas tests help to evaluate the level of oxygenation and type of acid-base disorder. Chest Roentgenography evaluation in patients with chronic Cor Pulmonale shows enlargement of the central pulmonary arteries with oligemic peripheral lung fields. A diameter of more than sixteen millimetres of the right descending pulmonary artery and more than eighteen millimetres of the left pulmonary artery suggests Pulmonary Hypertension. Two-Dimensional Echocardiography shows chronic right ventricular pressure overload. Doppler Echocardiography can be used to estimate pulmonary arterial pressure and is the most reliable non-invasive method to estimate pressure in the pulmonary artery. Ventilation / Perfusion Lung Scanning, Pulmonary Angiography and Chest CT Scanning aid the diagnosis of Pulmonary Thromboembolism as the underlying etiology of Cor Pulmonale (Jardin et.al, 2005). Magnetic Resonance Imaging (MRI) of the heart is another technique that provides valuable information about right ventricular mass and Radionuclide Ventriculography is a non invasive technique to determine right ventricular ejection fraction (RVEF). ECG changes in Cor Pulmonale include right axis deviation, R/S amplitude ratio in V1 greater than 1, R/S amplitude ratio in V6 less than 1 and P-Pulmonale pattern (Klinger et.al, 1991). 

Interventions

Interventions for chronic Cor Pulmonale is generally focused on treatment of the underlying pulmonary disease and improving oxygenation and RV function by increasing RV contractility and decreasing pulmonary vasoconstriction. Cardiopulmonary support includes fluid loading and administration of vasoconstrictors like epinephrin. Oxygen therapy, diuretics, vasodilators, digitalis, theophylline, and anticoagulation therapy are all different modalities used in the long-term management of chronic Cor Pulmonale. Diuretics improve the function of both the right and left ventricles. Calcium channel blockers lower pulmonary pressures and anticoagulation with warfarin is recommended in patients at high risk for thromboembolism (www.emedicine.com).

Conclusion

Cor Pulmonale is the failure of the right side of the heart caused by prolonged high blood pressure in the pulmonary artery and right ventricle of the heart. Elimination of the cause is the most important nurse intervention and latest investigative techniques like MRI Radionuclide Ventriculography and Echocardiogram provide valuable information for the treatment of Cor Pulmonale.

Reference

• Andrade Z, Andrade S (1970). Pathogenesis of Schistosomal Pulmonary Arteritis. Am J Trop Med Hyg .19:305-310.
• Antoine Vieillard-Baron, Bernard Page, Roch Augarde, Sebastien Prin, Salah Qanadli, Alain Beauchet, Olivier Dubourg, François Jardin (2001). Acute Cor Pulmonale in Massive Pulmonary Embolism: Incidence, Echocardiographic Pattern, Clinical Implications and Recovery Rate. Intensive Care Medicine.27 (9); 1481-1486.
• Antoine Vieillard-Baron, Sebastien Prin, Karim Chergui, Olivier Dubourg and François Jardin (2002). Echo-Doppler Demonstration of Acute Cor Pulmonale at the Bedside in the Medical Intensive Care Unit. American Journal of Respiratory and Critical Care Medicine .166; 1310-1319.
• H. I. Palevsky and A. P. Fishman (1990). Chronic Cor Pulmonale. Etiology and management. JAMA. 263(17).
• http://www.emedicine.com/MED/topic449.htm.
• Jardin F, Vieillard-Baron A (2005). Monitoring Of Right-Sided Heart Function. Curr Opin Crit Care. 11(3): 271-9.
• JP Battesti, R Georges, F Basset and G Saumon (1978). Chronic Cor Pulmonale in Pulmonary Sarcoidosis. Thorax.33; 76-84.
• Juan C. Gonzalez-Vitale and Rafael Garcia-Bunuel (2006). Pulmonary Tumor Emboli and Cor Pulmonale in Primary Carcinoma of the Lung. Cancer 38(5);2105 - 2110.
• Kapoor, S.C. (1959). Cor Pulmonale in Pulmonary Tuberculosis: A Preliminary Report on 66 Patients. Indian Journal of Tuberculosis 6 (2); 50-64.
• Klinger JR, Hill NS (1991). Right Ventricular Dysfunction in Chronic Obstructive Pulmonary Disease; Evaluation and Management. Chest. 99(3): 715-23.
• Krishnaswami, K.; Srinivasan, K.; Sivarajan, N. and Subramania Ram, V (1980). Cor Pulmonale in Chronic Pulmonary Diseases. Indian Journal of Tuberculosis.27 (2); 58-62.
• MacNee (1994). Pathophysiology of Cor Pulmonale in Chronic Obstructive Pulmonary Disease (Parts 1 & 2). Am J Respir Crit Care Med. 150:833.
• Mai Salama (2003). Serum Soluble Fas in Patients with Schistosomal Cor Pulmonale. Respiration.70:574-578.
• O. Robert Levine and Moises Simpser (1982). Alveolar Hypoventilation and Cor Pulmonale Associated with Chronic Airway Obstruction in Infants with Down syndrome. Clinical Pediatrics. 21(1); 25-29.
• Sadigursky M, Andrade ZA (1982). Pulmonary Changes in Schistosomal Cor Pulmonale. Am J Trop Med Hyg 31:779-784.
• Salvaterra, CG, Rubin, LJ (1993) Investigation and Management of Pulmonary Hypertension in Chronic Obstructive Pulmonary Disease. Am Rev Respir Dis. 148:1414.
• Shaul Sofer, Elliott Weinhouse, Asher Tal, Kenneth L, Wanderman, Giora Margulis, Alberto Leiberman and Moshe Gueron (1988). Cor Pulmonale Due to Adenoidal or Tonsillar Hypertrophy or Both in Children. Chest. 93:119-122.
• Stephen W. Royce (1951).Cor Pulmonale in Infancy and Early Childhood. PEDIATRICS.8 (2); 255-274.
• Vieillard-Baron et.al (2001). Acute Cor Pulmonale In Acute Respiratory Distress Syndrome Submitted To Protective Ventilation: Incidence, Clinical Implications, And Prognosis.Critical Care Medicine. 29(8):1551-1555.

Wiedemann, HP, Matthay, RA (1990). Cor Pulmonale. In: Decision Making in Emergency Medicine, Callaham, ML, Barton, CW, Schumaker, HM (Eds), Philadelphia, BC Decker p.120.

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