+++
CHAPTER SUMMARY AND CENTRAL ILLUSTRATION
++
Chapter Summary
This chapter describes a brief history of classification of the numerous types of congenital heart disease (CHD) lesions and the additive value of approaches (see Fuster and Hurst's Central Illustration), focusing on recent developments including the anatomic and physiologic (AP) classification and International Pediatric and Congenital Cardiac Code (IPCCC), the basis for ICD-11 codes. Historically, classification has focused on anatomy based on pathology investigations. With the advent of surgical options for CHD management in the 20th century, attention focused on distinctions relevant to available therapeutic decisions. These surgeries, and later catheter-based treatments, modify the initial CHD, often transforming the pathophysiology and long-term consequences. As more individuals survive longer with CHD, so does the need for a common language that comprehensively and concisely describes not only the underlying congenital heart lesion, but also prior medical interventions repairs and cumulative physiologic burden. Recent classifications have explored multiple dimensions to characterizing CHD. The recently proposed AP classification aims to represent CHD anatomy, along with pertinent interventions and current physiologic status. This provides useful nuance, but also adds complexity and associated challenges. Evolving clinical phenotype requires ongoing modification, but these classification efforts share a goal: to standardize and streamline communication and thereby improve outcomes.
++
+++
INTRODUCTION: THE NEED FOR COMPREHENSIVE CLASSIFICATION
++
As the number of individuals surviving with congenital heart disease (CHD) grows, so does the need for a common language that describes any given congenital heart lesion and its sequelae. Equally important is the ability to express information comprehensively and concisely. CHD encompasses a wide spectrum of cardiac malformations, ranging from simple to great complexity. This complexity relates not only to the native anatomy, but also to subsequent surgical repairs and long-term cumulative physiologic burden. As such, the same CHD diagnosis may be associated with heterogeneous implications for different patients. For example, take two patients with congenitally corrected transposition of the great arteries (TGA). The first is a 65-year-old patient with mild systemic ventricular dysfunction, no symptoms, and good exercise tolerance. The second is a 28-year-old with severe systemic ventricular dysfunction, prior mechanical systemic atrioventricular valve replacement, secondary prevention implantable defibrillator, and refractory clinical heart failure awaiting heart transplantation. The diagnosis of congenitally corrected transposition of the great arteries alone does not provide substantive insight into the patient’s clinical scenario.
++
In concept, a combined anatomic and physiologic (AP) classification system would allow healthcare providers to communicate the details around a CHD lesion in a standardized way, which is essential to both clinical practice and research. Such a system should represent the principal underlying anatomy as well as pertinent subsequent interventions and current clinical status. Key variables may include surgical and catheter interventions, current hemodynamics, symptoms, exercise tolerance, cardiac and noncardiac comorbidities, and ...