Changing demographics of pulmonary arterial hypertension in congenital heart disease

Abstract

Pulmonary arterial hypertension (PAH) is a serious complication of congenital heart disease (CHD). Without early surgical repair, around one-third of paediatric CHD patients develop significant PAH. Recent data from the Netherlands suggest that .4% of adult CHD patients have PAH, with higher rates in those with septal defects. A spectrum of cardiac defects is associated with PAH-CHD, although most cases develop as a consequence of large systemic-to-pulmonary shunts. Eisenmenger's syndrome, characterised by reversed pulmonary-to-systemic (right-to-left) shunt, represents the most advanced form of PAH-CHD and affects as many as 50% of those with PAH and left-to-right shunts. It is associated with the poorest outcome among patients with PAH-CHD. 40 yrs ago, ,50% of children with CHD requiring intervention died within the first year, and ,15% survived to adulthood. Subsequent advances in paediatric cardiology have seen most patients with CHD survive to adulthood, with resulting shifts in the demographics of CHD and PAH-CHD. The number of adults presenting with CHD is increasing and, although mortality is decreasing, morbidity is increasing as older patients are at increased risk of arrhythmia, heart failure, valve regurgitation and PAH. Data show that probability of PAH increases with age in patients with cardiac defects.KEYWORDS: Congenital heart disease, pulmonary arterial hypertension P ulmonary arterial hypertension (PAH), a disease of the pulmonary vasculature characterised by an elevated mean pulmonary arterial pressure (P pa) at rest of o25 mmHg [1], is one of the most serious complications of congenital heart disease (CHD). After idiopathic PAH (IPAH) and PAH associated with connective tissue diseases (PAH-CTD), it is the third most common form of PAH [2].A diagnosis of PAH has ramifications for both paediatric and adult CHD patients. In children, the course of CHD is complicated by the presence of PAH: estimates suggest that approximately one-third of paediatric CHD patients develop significant PAH without early surgical repair [3]. Increasing numbers of adults are presenting with CHD, illustrated by the fact that there are 1.2 million adult CHD patients in Europe alone, all of whom are at risk of developing PAH. The prevalence of PAH associated with CHD (PAH-CHD) was calculated as 4.2% among a population of 5,970 CHD patients included in the Dutch CONCOR registry, rising to 6.2% among 1,824 patients with septal defects [4]. In a separate Dutch study, 9.9% of 1,148 patients with CTD were found to have PAH [5].PAH can occur in association with a number of conditions other than CHD, although the underlying pathophysiology is similar in each case. Previous studies have suggested that PAH-CHD has a better prognosis than PAH of other aetiologies. Research has demonstrated an actuarial 3-yr survival rate for PAH-CHD of 77%, compared with only 35% at 3 yrs for untreated IPAH [6], 37% for PAH-CTD and 21% for PAH associated with HIV infection [3].Although progression of PAH appears slower in patients with ...

The challenge of managing pulmonary arterial hypertension in adults with congenital heart disease

“…Interestingly, in this study, the authors could not find a better survival for CHD patients compared with other PAH groups. It is a matter of debate whether this is due to a more frequent use of disease-targeting therapies (DTT) in other PAH groups or just a matter of lacking statistical power in a subgroup with relatively few events [29].…”

Detection of Intracardiac and Intrapulmonary Shunts at Rest and During Exercise Using Saline Contrast Echocardiography

“…Left-to-right shunts are clinically relevant because they can result in right heart volume overload and irreversible pulmonary hypertension (Mulder, 2010). Thus, evidence of right heart chamber enlargement or right-to-left shunt by saline contrast echocardiography is sufficient reason for further investigation to rule out significant left-toright shunting.…”

Can Pulmonary Vasodilator Therapy Expand the Operative Indications for Congenital Heart Disease?

“…1,2) However, pulmonary arterial hypertension (PAH) associated with CHD is still a serious problem. [3][4][5] The operability of CHD with left to right shunt depends on the severity of the pulmonary vascular disease induced by the increased pulmonary blood flow.…”