Pericardial Diseases

Pericardial Diseases

Pericarditis is the common pericardial disease that can be isolated or manifested as a systematic disease. Pericardial disease is the inflammation of the pericardium marked by chest pain, fever and audible friction. The pericardium is a layer wrapped around most of the heart, with the exception of the Left Atrium. Another very fine layer is the epicardium which is the inner layer attaching to the myocardium; the outer layer is thicker, fibrous, and relatively non-distensible. The pericardium is a fibro elastic sac surrounding the heart which contains a thin layer of fluid also known as the pericardial sac. Pericardial disease can cause pain and hemodynamic disturbances due to effusion and/or constriction. There are various causes of pericarditis, such as infectious and noninfectious causes.  Most cases of pericarditis remain idiopathic with conventional diagnostic evaluation.

This research paper deals with causes of different types of pericarditis, pathophysiology and their clinical manifestation. It also outlines management of various types of pericarditis. Treatment and management of pericardial diseases are largely empirical due to the lack of randomized trials. The diagnosis outlined includes differential diagnosis that tries to differentiate between the constrictive and restrictive pericarditis. Anti-inflammatory therapy is normally used in management of pericarditis.

Pericardial Diseases

Etiology

Pericardial diseases are broad spectrums that consist of congenital defects, neoplasm, cysts and pericarditis. Pericarditis can be effusive, dry, effusive-constructive and constructive. Etiological classification of pericardial diseases is comprised of infectious pericarditis, post-myocardial infarction syndrome, pericarditis in systematic autoimmune diseases, auto-reactive or the chronic pericarditis and type 2 autoimmune processes (Imazio, 2011). There are various causes of pericarditis that include viral infections, uremic pericarditis, bacterial infections, idiopathic and post-infarct pericarditis.

Pericarditis is the inflammation of pericardium which can be acute or chronic. Acute pericarditis that is or not associated with pericardial effusion may occur as one of the isolated clinical problems or as a systemic disease manifestation. According to Butman (2002), 90% of the isolated cases are idiopathic or viral, while other potential causes are widespread. There are rare causes of pericarditis that include tuberculosis and other bacterial infections, but acute pericarditis are caused by collagen vascular diseases, uremia, neoplasm and pericardial inflammation that occur due to pericardial injuries or acute myocardial infarction.

Pericarditis due to acute myocardial infarctions mostly occurs in one to three days after that transmural heart muscle infarction, due to the interaction of necrotic epicardium that is healing and the overlying pericardium. Myocardial infarction also causes another type of pericarditis, known as the Dressler’s syndrome that occurs after weeks or after months (Mayo Clinic Staff, 2012). This type is the same as that type of pericarditis that can occur in days or months after pulmonary infarction, traumatic pericardial injuries or after surgically manipulated pericardium. Dressler’s syndrome has been presumed, to be mediated by autoimmune mechanism and it is related to the signs of systemic inflammation, such as fever (Spangler, 2012). Pericarditis due to myocardial infarction frequency is reduced through the usage of reperfusion therapy.

Chronic pericarditis involves effusive, adhesive and constructive forms. Effusive pericarditis includes inflammation or hydropericardium in the heart failure. These pericardial effusions can appear as transudate, exudate, haemopericardium or pyopericardium. Large pericardial effusions occur commonly with tuberculosis, neoplastic uremia cholesterol myxedema and with parasitoses ( European Society of Cardiology, 2012).

Constrictive is a rare form of pericarditis, but it severely disables consequences of chronic pericarditis. This leads to the compromised filling of ventricles and impaired ventricle functions. Initially increased thickness in pericardium was considered as crucial diagnostic feature of constrictive pericarditis, but according to Wedro (2012), surgical procedures, tuberculosis and mediastinal irradiations are the frequent causative conditions of the disease.

Pericardial (congenital) cysts are not common, however; they can either be unilocular or multilocular. Inflammatory cysts consist of pseudocysts that are encapsulated and are loculated pericardial affusions that are caused by bacterial infections, such as tuberculosis, rheumatic pericarditis, trauma and cardiac surgery. Echinococcal cysts normally come from hydatid cysts that have ruptured in the liver and lungs.

Viral pericarditis is one of the most common infections of the pericardium. Inflammation of the pericardium is caused by direct attacks of viruses or the virus attacks the immune response or both. Early replication in the pericardial tissues provokes both cellular and humoral immune responses that act against the virus or the pericardium. Fragments of the viral genomes may not replicate, but they provide antigens that stimulate the body immune response. This leads to deposition of antibodies, such as IgM, IgG and rarely IgA on the pericardium tissues for many years. Viral pericarditis is caused by echo-, entero-, adeno-, influenza, herpes simplex cytomegalo-, Ebstein Barr hepatitis C, HIV and parvo B19 viruses (Spangler, 2012).

In neoplastic pericarditis, primary tumors of the pericardium are 40 times less than metastatic tumors ( European Society of Cardiology, 2012).  Mesothelioma is the common primary tumor which is very difficult to cure.  Secondary malignant tumors are malignant melanoma, breast cancer, lung cancer leukemia and lymphomas. Effusions can be large or small with forthcoming tamponade (the frequency of recurrence) or constriction. This can be the initial sign of a malignant disease and, as small effusions are collected, most patients are asymptomatic.

There are other rare forms of pericardial diseases, such as fungal, radiation, chylopericardium and drug and toxin related pericarditis. Fungal pericarditis is mainly found in immunocompromised patients or during endemics of acquired fungal infections.

Clinical Manifestations

Clinical features of different forms of pericarditis vary, but the common feature is the chest pain. General clinical manifestations of pericarditis include difficulty in breathing, muscle pain, cough, low-grade fever, abdominal swelling, lung congestion and a blue colored skin (Wedro, 2012). The complications of pericarditis include effusion, tamponade and myopericarditis. Chest pain can be painful and severe usually when the person is inspired or when in a supine position. This is relieved when the patient is leaning forward and sitting down. The pain is caused by the phrenic nerves causing irritation. Since pericarditis and pulmonary embolism is closely related, it is important that the difference in diagnosis should be done. A pericardial rub can be heard by a small area in the chest wall and may come and go with different body positions.

Viral infections are one of the main causes of pericarditis and pericardial effusions. Pericardial effusions are one of the most common types of pericardial diseases that are most harmful and the large ones causing problems by impairing heart function. Pericardial effusion might be caused by tumor, acute pericarditis, trauma, hypothyroidism, cardiac surgery, uremia or other inflammatory or non-inflammatory conditions.  As the pericardium becomes inflamed, extra fluid is produced, producing a pericardial effusion. Pericardial tamponade, also known as cardiac tamponade, is usually a consequence of increased pericardial pressure with accumulation of pericardial effusion.

Chronic pericarditis consists of effusive, adhesive and constrictive forms. The signs and symptoms include mild fatigue, palpitations and chest pain when related to pericardial inflammation and cardiac compression. Clinical features due to pericarditis in renal failure include pleuritic chest pain and fever; however, many patients suffering from this form of pericarditis appear asymptomatic. Others include persistence or transient pericardial rubs even in large effusions. Symptoms in uremic patients include slow heart rate (60-80 beats/min), hypotension, fever, resistance in erythropoiesis and anaemia ( European Society of Cardiology, 2012).

A patient with acute pericarditis experiences sharp retrosternal pain in the chest which can be severe and unbearable. Pericarditis, however, in some cases such as rheumatic arthritis that is accompanied by pericarditis is asymptomatic. The pain is normally worse with the inspiration and supine, but it is relieved when the patient sits forward. Pericardial pain is known as scapular ridge. It is assumed that this pain is caused by the irritation of phrenic nerves that are adjacent to the pericardial tissues. The chest pain due to acute pericarditis should be distinguished from the pain of myocardial infarction (ischemia) and pulmonary embolism.

Acute pericarditis is normally evidenced by systemic inflammation leukocytosis, increased Erythrocyte Sedimentation Rate (ESR) and elevated C-reactive protein. Low grade fever is usually common in acute pericarditis, but more than 38 degrees in temperature indicate purulent bacterial pericarditis. Troponin is minimally increased in the absence of increased total creatine kinase.

Patients who have pericardial constriction show increased systemic venous pressure with low cardiac output. Due to the balance between cardiac pressures, systemic overload or congestion is higher than pulmonary congestion. This attributes that the lungs remain clear, as there is hepatic congestion, peripheral edema, venous distension and ascites. The low cardiac output comes out as exercise in intolerance which can lead to development of cardiac cachexia and muscle wasting (UMMC, 2011). Clinical features in pericardial constriction that have stood for long include hepatic dysfunction, ascites and pleural effusions. Patients suffering from pericardial constriction are most likely to get left-sided (bilateral) pleural effusions and sometimes right-sided effusions. The clinical manifestations of restrictive cardiomyopathy especially the one caused by cardiac amyloid closely resemble those of pericardial constriction.

Patients with neoplastic pericarditis may appear asymptomatic, but with signs of dyspnea, tachycardia, jugular venous distension, cough and chest pain. These symptoms are only observed when fluid volume exceeds 500 ml. Some of important signs of cardiac tamponade include hypotension, pulsus paradoxus and cardiogenic shock (Wedro, 2012). The presence of effusion, constriction or tamponade can be confirmed on echocardiography. Tamponade is the potential life threat. It is diagnosed by the clinical research of elevated jugular venous pressure, decreased blood pressure and muffled heart sounds on auscultation.

Fungal pericarditis clinical features show a broad spectrum of all pericardial diseases that include fungal myocarditis. The endemic fungi that cause fungal pericarditis include Coccidioides and Histoplasma, while the non-endemic opportunistic fungi include Blastomyces, Aspergillus and Candida. Semi-fungal agents include the Actinomyces and Norcadia (Mayo Clinic Staff, 2012).

Pathophysiology

Pericardium has two layers that include the inner visceral layer and the outer parietal layer. The parietal layer is fibrous; it provides rigidity to the outer shell of the pericardial cavity. It lies adjacently with the inner layer. Parietal layer consists of collagen layers that have interspersing elastin fibrils. The visceral layer looks like a tissue-paper and it lies side by side of the heart.  It is adherent to the pericardium. Visceral layer contains microvillus surface, whose function is to secrete pericardial fluid. Both layers are 1-2 mm in thickness and have a space that has 15-35 ml of pericardium fluid that separates these layers (BMJ Publishing Group Limited, 2011).

Pericardium is normally innervated by phrenic nerve and perfused by internal mammary arteries. Pericardium restrains and protects the heart. Other functions include determination of cardiac filling pattern, offer equilibrium compliance between ventricles and limit heart chamber dilatation (Imazio, 2011).

Pericardium is affected by various forms of pericarditis. For instance, renal failure which occurs in two forms is one of the common causes of pericardial diseases that result in to large effusions. First, the uremic pericarditis results from the inflammation of both visceral and parietal pericardium. The second type is the dialysis associated pericarditis that shows the adhesion between thick pericardial membranes.

Diagnosis and Differential Diagnosis

Chest pain is an important factor to diagnose with Pericarditis. Constrictive pericarditis is a late sequela, which means it is a condition related to or a consequence of a previous disease, also an inflammatory condition of the pericardium. This inflammation is usually an infection caused by heart attack or heart surgery.  It is diagnosed in 5% of patients presenting to the hospital emergency departments with chest pains in the absence of a myocardial infarction. It is important to examine the heart when the patient moves in different positions, leaning forward and using the diaphragm to listen when the patient is not breathing briefly. If absent sounds are heard during the respiration, it is a pleural rub rather than a pericardial rub.

Diagnosis of neoplastic pericarditis is based on confirmation of malignancy in the pericardium. UMMC (2011) argues that 2/3 of patients who have pericardial effusions are caused by non-malignant diseases, such as opportunistic infections and radiation pericarditis. The chest CT and roentgenogram are some of the diagnostic procedures that can be carried out to confirm the mediastinal widening, pleural effusion and hilar masses. Malignant pericardial disease can be confirmed through the analysis of pericardial (epicardial) biopsy and pericardial fluid.

Diagnosis of fungal pericarditis is found by staining and cultures of pericardial tissues and fluid. Serum antifungal antibodies also help in the establishment of diagnosis of fungal infection. Viral pericarditis can be diagnosed using the PCR technique. This technique has a higher specificity and sensitivity, as compared to isolation of viruses from tissues and fluids (Butman, 2002).

Pericardial constriction should be examined in patients who have mysterious systemic venous congestion. The echocardiography is used in the differentiation between pericardial constriction and the right heart failure that is caused by tricuspid valve diseases or pulmonary hypertension. It is difficult to differentiate between restrictive cardiomyopathy and pericardial constriction. Doppler echocardiography is an essential method that distinguishes restriction from constriction ( European Society of Cardiology, 2012). Pericardial constriction patient has a clear respiratory variation of mitral flow which is absent in restrictive cardiomyopathies. There is an elevated venous pressure in pericardial constriction and respiratory variation is present when head-up tilt is there only.

In Doppler measurement, early diastolic mitral annular velocity (Ea) is mostly decreased in patients with myocardial restriction while in patients who have pericardial constriction is normal. The optimum discrimination follows an Ea velocity of 8 cm/s and rapid circulation of early diastolic flows to apex, and is normally preserved in constriction and decreases in myocardial restriction.

Both constriction and restriction were formally distinguished at the cardiac catheterization using hemodynamic criteria. In the constriction there is exact equal amount of diastolic pressures in the left and right parts of the heart. This differs in restriction, since the left ventricular end diastolic pressure overwhelms the right ventricle pressure with few mm Hg. Pulmonary hypertension is often seen as restrictive, but it is not frequently seen in constriction. All this brings about the idea that the right ventricle diastolic pressure has to be higher with one the third of right ventricle systolic pressure in the constriction.

Hemodynamic principle has limited specificity in the differentiation of cardiomyopathies from pericardial constriction (BMJ Publishing Group Limited, 2011). On the contrary, the dynamic variations of the respiratory that indicates elevated ventricle interdependence is superior. Inspiration in constriction, the right ventricle systolic pressure increases as the left ventricle systolic pressure reduces.  The inverse of this takes place during expiration. It is one of the findings that have high specificity and sensitivity in the recognition of constriction pericarditis versus myocardial restriction. Endomyocardial biopsy that can be performed during catheterization is also used in some cases to differentiate between the pericardial constriction and myocardial disease.

Management and Outcome

Most patients with cardiac tamponade do not have solutions to their elevated right arterial pressure after the removal of pericardial fluid. Pericardiocentesis is carried out to such patients in order to convert hemodynamics of the tamponade to that of constriction. This shows that cardiac filling restrictions are not only caused by pericardial effusions, but also pericardial construction in the visceral pericardium. Therefore, pericardiocentesis can be carried out in patients with pericarditis after radiation, due to malignancies, tuberculous pericarditis and idiopathic pericarditis (Spangler, 2012).

Pericardiectomy is the removal of visceral pericardium. It is the process that can be carried out to patients with effusive constrictive pericarditis that transits from acute pericarditis with effusion to the pericardial constriction. According to UMMC (2011), nutrition and its supplements can be used to manage constrictive pericarditis. Use of low-salt diets and avoidance of alcohol, saturated fats and sugars that weaken the immune system and increase the inflammation manage pericarditis.

Radiation therapy is an effective control of malignant pericardial effusion, especially in patients who have radiosensitive tumors that include leukemia and lymphomas. However, heart radiotherapy has been known to cause pericarditis and myocarditis. Subxyphoid pericardiotomy is recommended when pericardiocentesis cannot be carried out. The procedure may be carried out locally in anaesthesia, but it has complications such as pneumothorax, myocardial laceration and mortality. Pleuropericardiotomy allows the drainage of malignant fluid in the oericardium in to the pleural space ( European Society of Cardiology, 2012). This is associated with a number of complications and has disadvantages over pericardiocentesis.

Antifungal treatment using amphotericin B, fluconazole, itraconasole and ketoconazole is indicated in management of antifungal pericarditis. Corticosteroids support treatment using antifungals. Patients already suffering from histoplasmosis and get pericarditis do not require antifungal therapy. This is because these patients respond to the treatment of non-steroidal anti-inflammatory drugs administered for two to twelve weeks. Norcadiosis is a fungal infection that is treated using sulfonamides as the drugs of choice, while actinomycosis is treated using antibiotics, such as penicillin (Wedro, 2012). Pericardiocentesis is the surgical treatment that is used to manage hemodynamic impairment while pericardiectomy manages fungal constrictive pericarditis.

Summary

Pericardial diseases lead to the swelling and irritation of pericardial tissues. Pericarditis refers to the inflammation and swelling of the pericardial tissues. Pericarditis normally causes chest pain and other symptoms. It is normally sudden and short-lived or acute. When symptoms are more gradual and persistent it is considered as chronic. Mild cases of pericarditis can improve by themselves. Pericardium is the fibrous sac that surrounds the heart. Pericarditis is characterized by the chest pain which can be recurrent. This disease, like most others, may not be prevented until the underlying causes have been found and treated. 

Pericardium influences the performance of the cardiac indirectly and pathological conditions affect cardiac functions. Several modes have been used clinically, in order to understand pathophysiology of pericardial diseases. Increase in pericardial pressures reduces the transmural pressure of both cardiac chambers, resulting to the compromised process of filling and output. This problem is relevant today due to the increased cardiac tamponade incidences that result from an increased usage of antiplatelet agents that are combined with the wide range of invasive devices (Imazio, 2011). The most common causes of pericarditis are idiopathic and viral, and the most common treatment for these is non-steroidal anti-inflammatory drugs and colchicine.

Clinical manifestations of different patients depend on the patients’ family history or background, and environmental factors of daily living. However, this disease may not be prevented until underlying causes have been caught; otherwise, unknown in some cases. These diseases and conditions like many others can inflame the membranous covering of the heart, including infections, fever, myocardial infarction, cancer and renal failure and trauma. In many instances, the precise cause is unknown. The origin of Pericardial Disease is the surrounding of the heart through the pericardial sac, development of thoracoscopy, most specifically in the diagnosis of post-inflammatory, inflammatory, autoreactivity and neoplastic pericardial diseases.

Though it is not common during diagnosis, despite the excellent work that is done by various noninvasive techniques, constrictive pericarditis can be missed, hence, its diagnosis remains difficult. Treatment of severe cases of pericarditis includes medication; surgery is rarely used. Early diagnosis of pericarditis and management reduce the risks of long-term complications.

Pericardial effusions cause infections such as: HIV, echoviruses, cytomegalovirus and coxsackieviruses. Treatments for pleural effusions often mean to treat what the underlying cause of the pleural effusion itself. Some indications, such as antibiotics or diuretics, can be given if pneumonia or congestive heart failure is present. Often times fluid, inflammation or infection causes these effusions. A chest tube, also known as Tube Thoracotomy, is done by surgically making an incision in the chest wall and inserting a plastic tube into the pleural space, draining the fluid.

Elevation of the intrapericardial pressure can lead to a progressive limitation of early diastolic ventricular filling which, in return, results in a low cardiac output. The diagnosis is based on clinical presentation and echocardiography. Patients are usually monitored closely for the symptoms of cardiac effects (tamponade), clammy skin, pulsus paradoxus, peripheral pulses, distended neck veins and decreased blood pressure. Such cases are idiopathic, hence, reflecting the frequency of pericardial disease, in general. The need of being dependent on severity can include radiation, chemotherapy, resolution of infections, neoplasia and other post-surgical procedures.

Thoracentesis can be done to drain large amounts of fluid. Pleural drainage is also used for reoccurring pleural effusions inserting a catheter into the skin and into the pleural space. Doing this can eliminate a hospital visit and the patient can do this at home. Pleurodesis is a medication called Doxycycline or Talc which is injected through a chest tube and into the pleural space, forcing the chest wall and pleura to heal with each other. This often stops the pleural effusion from happening repeatedly. If necessary a Pleural Decortication can be done through an operation performed by a surgeon, physically removing the inflammation and or tissue.