Hemodynamically Unstable Presentations of Congenital Heart Disease in Adults

Recent decades have seen great growth in the number of adults with congenital heart disease (ACHD). Between 1985 and 2000, the number of adults with congenital heart disease has doubled, resulting in approximately 1 million adult survivors in the United States who are increasingly having late complications. This is accompanied by a similar increase in hospitalizations as more adult patients develop late complications of disease. As this population has emerged, adult caregivers are seeing more congenital heart disease in practice but may have little training in providing care for it. The anatomy and nomenclature of congenital heart disease is often intimidating to a cardiologist treating ACHD, but the care in most cases is analogous to that of other adult patients. For example, the care of a young adult with heart failure from a failing systemic right ventricle (RV) is modeled after the deep clinical experience caring for patients with left ventricular (LV) failure. Being aware of congenital anatomy and the complications that are frequently seen in common congenital lesions, however, is important to help focus on the likely diagnosis and optimal treatment plan.

In general, patients with congenital heart disease come to medical attention as adults because they have one or more of the conditions presented in Box 33.1 .

Most of these lesions never present as cardiac emergencies. However, unique conditions related to surgical techniques and long-term physiologic burdens do generate potential for emergent presentations in this patient group. These conditions include the history of incisions in the atrium or ventricle affecting the conduction system or forming fibrous scars as the basis for arrhythmias, an anatomic RV functioning as a systemic ventricle for decades, and residual lesions forming substrate for infective endocarditis ( Table 33.1 ). Another example is the fall in systemic vascular resistance in these patients with Eisenmenger syndrome who become pregnant increases the right-to-left shunt and results in arterial desaturation.

Most emergent complications seen in congenital heart disease, however, are similar to the emergency situations seen in adults with acquired rather than congenital heart disease. For example, the diagnosis of ventricular tachycardia in a patient with repaired tetralogy of Fallot is treated in a manner similar to the patient with coronary disease and ventricular tachycardia—unfortunately, with the same uncertain efficacy. What is important to remember is that a patient with repaired tetralogy of Fallot is at risk of developing ventricular tachycardia and to recognize the importance of investigating complaints of palpitations, presyncope, and syncope. Substantial analogies to the care of general cardiac patients exist, but this needs to be combined with knowledge of what complications to expect with what lesion and management needs to be tailored to an ACHD patient's unique anatomy ( Table 33.2 ).

Congenital heart disease can predispose the patient to certain complications that may be responsible for precipitating a cardiac emergency. For example, in a patient with L-transposition of the great vessels and shortness of breath, the RV is acting as the systemic ventricle and is prone to failure. The diagnosis of heart failure is not difficult and treatment is similar to the treatment of congestive heart failure due to other conditions.