Constrictive pericarditis is the sequelae of chronic fibrosis and thickening of the pericardium as a result of chronic inflammation.
Etiology
The etiology of constrictive pericarditis is similar to acute pericarditis with effusion. (Table).
Table : Causes of Constrictive Pericarditis
1) Tuberculous pericarditis.
2) Pyogenic pericarditis.
3) Viral pericarditis.
4) Fungal pericarditis.
5) Trauma.
6) Radiation.
7) Immunologic disorder.
• Systemic Lupus erythmatosis.
• Rheumatoid disease.
8)Idiopathic.
Pathophysiology
The thickened and rigid pericardium causes constriction of the heart and restricts ventricular dialatation and diastolic filling of the ventricles. The thickened rigid pericardium can cause dissociation of intracardiac and intrathoracic pressures and elevation of diastolic intracardiac pressures. This results in systemic and pulmonary venous congestion. Since the early phase of ventricular relaxation is normal, the early filling of the ventricles take place normally. Further relaxation of ventricles are restricted by the thickened pericardium resulting in acute elevation of diastolic ventricular pressure which gives a square root (“) appearance to the diastolic ventricularpressure tracing. Uniform constriction of all the four cardiac chambers results in equalization of diastolic pressures in all the four chambers. This is different from restrictive cardiomyopathy where the difference in diastolic pressure between ventricles will be more than 5 mm. of Hg.The myocardium is usually normal in structure and function. This results in good systolic function.The ventricular filling takes place during early filling phase only as further filling is prevented by the thickened and rigid pericardium.
Clinical Features
Constrictive pericarditis (CP) has an insidious onset with features of early cardiac failure like fatigue, reduced exercise tolerance, exertional beathlessness and oedema of the legs. Abdominal distension secondary to chronic hepatomegaly and acites can occur.
Signs
1) Jugular venous pressure (JVP) is elevated in all patients of CP which reflects the elevated diastolic pressure of the right atrium. In CP, the JVP can engorge during inspiration, known as Kussmaul’s sign; there can be prominent ‘Y’ descent representing early rapid filling of the right ventricle, Friedrich’s sign.
2) One third of CP patients have irregularly irregular pulse due to atrial fibrillation. In patients with effusive CP there can be pulsus paradoxus.
3) Praecordial examination may reveal cardiomegaly by percussion. The first heart sound may be muffled. A pericardial knock, which is due to early cessation of ventricular filling due to pericardial restriction is audible. This is a high pitched sound audible in diastolic phase earlier than the timing of S3. Murmurs are not common even though atrioventricular valve regurgitations due to alteration of ventricular geometry have been described.
4) Hepatomegaly and ascites are almost always present. Splenomegaly is detected in chronic cases.
Investigations
Electrocardiogram
Low voltage complexes can occur. Left atrial enlargement may be seen. Atrial fibrillation occurs in about one fourth of patients.
X-ray Chest
Cardiac enlargement occurs in almost half of the cases. Pericardial calcification is seen in chronic cases. Pericardium over the inferior surface and free wall of left ventricle, over the right ventricle and atrioventricular groove are common sites for calcification. Calcification is best seen in lateral film.
2-Dimensional Echocardiography
Thickened pericardium can be detected. In about a third of patients there will be associated some degree of pericardial fluid. Sudden anterior motion of interventricular septum following atrial systole is a feature. On Doppler evaluation, respiratory variation of atrioventricular valve flow will be detected – there will be significant decrease in mitral flow and increase in tricuspid flow during inspiration. This difference can be 33 per cent and above. Opposite changes are seen during expiration. Pulmonary venous flow in CP will show decreased systolic to diastolic flow ratio. There will be significant increase in pulmonary venous flow during expiration. Similarly the venous flow pattern in inferior venacava can show decreased systolic to diastolic flow ratio and marked increase in flow during inspiration. In restrictive cardiomyopathy, the prominent respiratory variation of the venous flow does not happen.
Haemodynamic Study
Simultaneous right and left heart studies are useful. Due to exaggerated waves in atria, W-shaped atrial pressure tracing will be seen. There will be equalization of end diastolic pressure in all the four chambers of the heart (difference will be less than 5 mm. of Hg.). The ventricular diastolic pressure wave will show the square root sign (“). The end diastolic pressure in both the ventricles will be elevated and almost equal with the difference being less than 5 mm. of Hg. The right ventricular diastolic pressure will be usually more than one third the right ventricular systolic pressure.
Treatment
Medical Treatment
1) Judicious use of diuretics to alleviate systemic congestion. This may be enough in some cases of mild CP.
2) Specific treatment of etiology. Any treatable etiology has to be treated, e.g., tuberculosis.
Surgical Treatment
Pericardiectomy will relieve constriction in more than 80 per cent of patients and will provide good symptomatic relief. The procedure carries 10 per cent — 20 per cent mortality. The risk is higher in patients with greater functional disability.
Etiology
The etiology of constrictive pericarditis is similar to acute pericarditis with effusion. (Table).
Table : Causes of Constrictive Pericarditis
1) Tuberculous pericarditis.
2) Pyogenic pericarditis.
3) Viral pericarditis.
4) Fungal pericarditis.
5) Trauma.
6) Radiation.
7) Immunologic disorder.
• Systemic Lupus erythmatosis.
• Rheumatoid disease.
8)Idiopathic.
Pathophysiology
The thickened and rigid pericardium causes constriction of the heart and restricts ventricular dialatation and diastolic filling of the ventricles. The thickened rigid pericardium can cause dissociation of intracardiac and intrathoracic pressures and elevation of diastolic intracardiac pressures. This results in systemic and pulmonary venous congestion. Since the early phase of ventricular relaxation is normal, the early filling of the ventricles take place normally. Further relaxation of ventricles are restricted by the thickened pericardium resulting in acute elevation of diastolic ventricular pressure which gives a square root (“) appearance to the diastolic ventricularpressure tracing. Uniform constriction of all the four cardiac chambers results in equalization of diastolic pressures in all the four chambers. This is different from restrictive cardiomyopathy where the difference in diastolic pressure between ventricles will be more than 5 mm. of Hg.The myocardium is usually normal in structure and function. This results in good systolic function.The ventricular filling takes place during early filling phase only as further filling is prevented by the thickened and rigid pericardium.
Clinical Features
Constrictive pericarditis (CP) has an insidious onset with features of early cardiac failure like fatigue, reduced exercise tolerance, exertional beathlessness and oedema of the legs. Abdominal distension secondary to chronic hepatomegaly and acites can occur.
Signs
1) Jugular venous pressure (JVP) is elevated in all patients of CP which reflects the elevated diastolic pressure of the right atrium. In CP, the JVP can engorge during inspiration, known as Kussmaul’s sign; there can be prominent ‘Y’ descent representing early rapid filling of the right ventricle, Friedrich’s sign.
2) One third of CP patients have irregularly irregular pulse due to atrial fibrillation. In patients with effusive CP there can be pulsus paradoxus.
3) Praecordial examination may reveal cardiomegaly by percussion. The first heart sound may be muffled. A pericardial knock, which is due to early cessation of ventricular filling due to pericardial restriction is audible. This is a high pitched sound audible in diastolic phase earlier than the timing of S3. Murmurs are not common even though atrioventricular valve regurgitations due to alteration of ventricular geometry have been described.
4) Hepatomegaly and ascites are almost always present. Splenomegaly is detected in chronic cases.
Investigations
Electrocardiogram
Low voltage complexes can occur. Left atrial enlargement may be seen. Atrial fibrillation occurs in about one fourth of patients.
X-ray Chest
Cardiac enlargement occurs in almost half of the cases. Pericardial calcification is seen in chronic cases. Pericardium over the inferior surface and free wall of left ventricle, over the right ventricle and atrioventricular groove are common sites for calcification. Calcification is best seen in lateral film.
2-Dimensional Echocardiography
Thickened pericardium can be detected. In about a third of patients there will be associated some degree of pericardial fluid. Sudden anterior motion of interventricular septum following atrial systole is a feature. On Doppler evaluation, respiratory variation of atrioventricular valve flow will be detected – there will be significant decrease in mitral flow and increase in tricuspid flow during inspiration. This difference can be 33 per cent and above. Opposite changes are seen during expiration. Pulmonary venous flow in CP will show decreased systolic to diastolic flow ratio. There will be significant increase in pulmonary venous flow during expiration. Similarly the venous flow pattern in inferior venacava can show decreased systolic to diastolic flow ratio and marked increase in flow during inspiration. In restrictive cardiomyopathy, the prominent respiratory variation of the venous flow does not happen.
Haemodynamic Study
Simultaneous right and left heart studies are useful. Due to exaggerated waves in atria, W-shaped atrial pressure tracing will be seen. There will be equalization of end diastolic pressure in all the four chambers of the heart (difference will be less than 5 mm. of Hg.). The ventricular diastolic pressure wave will show the square root sign (“). The end diastolic pressure in both the ventricles will be elevated and almost equal with the difference being less than 5 mm. of Hg. The right ventricular diastolic pressure will be usually more than one third the right ventricular systolic pressure.
Treatment
Medical Treatment
1) Judicious use of diuretics to alleviate systemic congestion. This may be enough in some cases of mild CP.
2) Specific treatment of etiology. Any treatable etiology has to be treated, e.g., tuberculosis.
Surgical Treatment
Pericardiectomy will relieve constriction in more than 80 per cent of patients and will provide good symptomatic relief. The procedure carries 10 per cent — 20 per cent mortality. The risk is higher in patients with greater functional disability.
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