Chapter 11

    When as a consequence of a large shunt between the right and left side of the heart, the pulmonary vascular resistance equals or surpasses the systemic, the patient will develop the so-called Eisenmenger's syndrome.

ANATOMICALLY

    Each patient will primarily have the type of shunt responsible for his basic congenital disease (ventricular septal defect, patent ductus arteriosus, atrial septal defect, etc.).
    The Eisenmenger's syndrome, in any event, will be clinically, electrocardiographically and roentgenographically the same regardless of the congenital disease responsible for the case. This is why at this hemodynamic stage, it will be almost impossible to distinguish between different congenital diseases without cardiac catheterization and angiography.
    As just expressed, the anatomy will depend on the basic congenital disease, but these patients will invariably have large hypertrophy of the right ventricle due to elevation of the pulmonary vascular resistance (pulmonary hypertension), and hypertrophy of the pulmonary artery with dilatation of its main trunk and main branches. The microscopical typical changes of pulmonary hypertension will be present in the lungs.
    The total heart size can be grossly normal or moderately enlarged. If the patient basically has ventricular septal defect or patent ductus arteriosus, there will be left ventricular hypertrophy.

HEMODYNAMICS AND PHYSIOPATHOLOGY

    The hemodynamics will be determined primarily by the pulmonary hypertension and the originally left to right shunt will be bidirectional or inverted to a right to left shunt. As a consequence the patient will typically present, right ventricular systolic and volume overload.
    Due to systemic pulmonary resistance, permanent mild cyanosis will be almost the rule which may markedly increase with exertion. In the case of patent ductus arteriosus this peripheral hypoxia can be prevalent in the trunk and patient's legs.

CLINICAL PICTURES

    The left ventricular impulse will be no longer palpable. Impulse will be present in the low left sternal border and occasionally in the right low sternal border due to right ventricular hypertrophy.
    If the pulmonary systolic pressure is higher than 60 mm Hg, the second sound will be many times palpable in the second and third left intercostal spaces. Pulsations due to the pulmonary artery dilatation will also be detectable.
    The inspection of the patient will many times lead to the discovery of clubbing and cyanosis which is mild to moderate in most of the cases and even difficult to detect in some patients. With exertion the cyanosis typically increases.
    Auscultation will reveal a normal first sound with a very loud second sound. Fixed splitting of the second sound will favor atrial septal defect, as etiology of the complex.
    A typical systolic ejected murmur in the area of the pulmonary artery is almost always present with an early diastolic murmur due to pulmonary valve regurgitation.
    Right ventricular gallop (S3) and right atrial gallop (S4) may be heard at times.
    The most common symptoms are the ones of easy fatigability and moderate shortness of breath which increases with physical exertion.
    Signs of congestive failure can be seen and hemoptosis can occur in a large number of these patients.
    Squatting is rare, but the side effects of polycythemia and cyanosis are occasionally seen mainly in young infants. These patients may eventually die suddenly as consequence of heart failure or arrhythmias. Few survive more than 35 years.
    Eisenmenger's syndrome occurs more frequently as a consequence of ventricular septal defect being followed closely by patent ductus arteriosus. Atrial septal defect does not very often lead to pulmonary hypertension and Eisenmenger's syndrome, although the varieties related to endocardial cushion defect (ostium primum) may also lead to this complex quite often.

ELECTROCARDIOGRAM

    The electrocardiographic pattern in Eisenmenger's syndrome is classical. The main features will be the one of marked systolic right ventricular overload and hypertrophy. In any event, the findings due to such systolic overload will not be so prominent in the electrocardiogram as the one observed in pulmonary valve stenosis with intact intraventricular septum.
    The main axis over the frontal plane will be markedly deviated toward the right due to a deep and at times wider than normal S wave in lead I.
    A tall R wave (usually taller than 10 mm), will dominate in leads V₁ and V₂.
    Often, T waves will be inverted in leads V₁ and V₂, although at times the T waves may be positive or biphasic in such leads. Occasionally qR complexes will be seen in leads V₁ and V₂ with R wave wider than normal with indentations in the ascending limb. (Such changes are observed prevalently in patients with marked hypertrophy of the right ventricular free wall and intraventricular septum.)
    The PR interval may be moderately prolonged in 25-35 % of the patients, but second or third degree AV block is unusual.
    Signs of right atrium overload will be seen in 25 % of the cases with tall and narrow P waves in leads II and V₁.
    In a few cases, left atrial hypertrophy will be observed with the P wave wider than normal and bicuspid in leads I, V₅ and V₆.
    As a general rule in cases of pulmonary hypertension, electrical changes will supervene when the mean pulmonary artery pressure is over 60 mm Hg. Eisenmenger's syndrome, in any event, by definition,means pulmonary vascular resistance equal to or greater than the systemic with a clinical picture which is similar regardless of the shunt site.

ROENTGENOGRAM

    A chest x-ray is typically characterized by:

1. Hypertrophy and dilatation of the pulmonary artery
2. Clear peripheral lung fields
3. Enlargement of the hilar vascular shadows
4. Right ventricular hypertrophy

    In case of ventricular septal defect and patent ductus arteriosus, moderate enlargement of the left ventricle may be seen, too.
    In case of ostium primum, moderate enlargement of the left ventricle can be present too.
    The aortic knob is usually smaller than normal in atrial septal defect and ventricular septal defect, being larger than usual in patent ductus arteriosus.
    Other than that, no group exhibits any real particular featues in the roentgenogram and electrocardiogram to distinguish between the different etiological congential diseases in the case of Eisenmenger complex.

CARDIAC CATHETERIZATION AND ANGIOCARDIOGRAPHY

    The catheterization will essentially demonstrate pulmonary hypertension with systemic or higher than systemic pressure.
    There will be a right to left or a bidirectional shunt present.
    As in any one of the congenital diseses able to lead to this complex, passing of the catheter through the defect may be observed.
    Arterial unsaturation at rest will be also demonstrated.
    The pulmonary vascular resistance is fixed and will have no variation with the breathing of 100 % oxygen or with the use of pulmonary vasodilators.
    The location of the shunt can be demonstrated by angiography. Dilution curves may be used in the same sense.
    The study of oxygen saturation will show decrease beyond the location of the shunt.

MEDICAL AND SURGICAL TREATMENT

    The medical treatment will be limited to the control of the congestive heart failure and prevention of bacterial endocarditis.
    Surgical correction of the basic malformation is usually contraindicated. Patients may develop acute failure of the right ventricle after the closure of the shunt.
    In any event, differential diagnosis with essential pulmonary hypertens ion and other diseases leading toward pulmonary hypertension, as recurrent pulmonary embolish, should be done.

Eisenmenger Syndrome in a 21 year-old female with ASD.

33 year-old patient with VSD and severe Pulmonary Hypertension.

Portrayal of catheterization pressure findings and oxygen saturation at different chambers in a patient with ventricular septal defect and almost systemic pulmonary pressure.