Adult Congenital Heart Disease

Chapter 45


Adult Congenital Heart Disease





1. Which patients with adult congenital heart disease require antibiotic prophylaxis?


    The indications for antibiotic prophylaxis for endocarditis changed in 2007 with the new American Heart Association guidelines. A more restricted use of antibiotic prophylaxis in congenital heart disease is proposed, with increased emphasis on oral health. Prophylaxis is now suggested only in the following circumstances:



The new guidelines have also eliminated indications for prophylaxis for genitourinary (GU) or gastrointestinal (GI) procedures. (See also Chapter 33 on endocarditis and endocarditis prophylaxis).


2. What are the three main types of atrial septal defects (ASDs), and what are their associated anomalies?


    The three main types of ASDs are secundum (70%), primum (20%), and sinus venosus (10%). The secundum ASD is a defect involving the floor of the fossa ovalis of the atrial septum. It usually presents as an isolated anomaly. The primum ASD is a defect at the base of the atrial septum adjacent to the atrioventricular valves. It is invariably part of an atrioventricular septal defect (endocardial cushion defect), and a cleft mitral valve is almost always present. The sinus venosus ASD is a defect of the posterior part of the septum, usually located in the superior part. In the majority of cases, a sinus venosus ASD is associated with anomalous connections or drainage of the right-sided pulmonary veins (Fig. 45-1).



3. When should an ASD be closed? Which ASDs cannot be closed by a percutaneous device?


    ASDs vary in size. If the ASD is large enough, the associated left to right shunt will lead to right-sided volume overload and pulmonary overcirculation. Chronic right-sided volume overload leads to pulmonary hypertension, right ventricular dysfunction, tricuspid regurgitation, and right atrial dilation. Patients with ASDs also often develop atrial arrhythmias. Hemodynamically significant ASDs are usually 10 mm or larger, have a shunt ratio greater than 1.5, and are associated with right ventricular enlargement on imaging. It is recommended that only hemodynamically significant ASDs be closed. Most secundum ASDs can be closed percutaneously. Primum and sinus venosus ASDs cannot be closed percutaneously and require surgical closure.


4. List the four types of ventricular septal defects (VSDs).


    Different classifications for VSDs have been used; one common approach divides VSDs into four types:



image Membranous or perimembranous VSDs involve the membranous ventricular septum, a small localized area of the normal ventricular septum that is fibrous. This is the most common type of VSD seen in the adult.


image Muscular VSDs involve the trabecular portion of the septum.


image Inlet VSDs involve the part of the ventricular septum that is adjacent to the tricuspid and mitral valves. Inlet VSDs are always associated with atrioventricular septal defects.


image Outlet VSDs (also known as supracristal VSD) involves the portion of the ventricular septum that is just below the aortic and pulmonary valve (Fig. 45-2).



5. What are the long-term complications of a small VSD in the adult patient?


    In the adult, there are two groups of patients with unrepaired VSD. The smallest group consists of patients with a large VSD that has been complicated by severe pulmonary hypertension (Eisenmenger syndrome). However, the vast majority of adult patients with VSDs have small defects that are hemodynamically insignificant (i.e., do not cause left ventricular dilation or pulmonary hypertension). As a rule these patients have a benign natural history. Rarely, some patients develop complications such as endocarditis, atrial arrhythmias, tricuspid regurgitation, aortic regurgitation, and double-chamber right ventricle.


6. What are the complications of a bicuspid aortic valve?


    A bicuspid aortic valve is present in 0.5% to 1% of the population. The main complications are progressive aortic stenosis, aortic regurgitation, or a combination of both. Other complications include endocarditis and aortopathy. Although infrequent (<10%), aortic coarctation is also a well-described association and must be ruled out in these patients. Patients in whom the bicuspid valve demonstrates signs of valve degeneration on echocardiography are at an increased risk of cardiovascular events and need close regular follow-up.


7. How is hemodynamic severity of coarctation of the aorta assessed in the adult patient?


    In coarctation of the aorta, the narrowing is typically in the proximal portion of the descending aorta, just distal to the left subclavian artery. Adult patients can be divided into two groups: those with native

Related posts:

  1. Exercise Stress Testing
  2. Nuclear Cardiology
  3. Endomyocardial Biopsy
  4. Pulmonary Hypertension

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Jun 5, 2016 | Posted by in CARDIOLOGY | Comments Off on Adult Congenital Heart Disease

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