15-year mortality 10 times higher among congenital heart surgery survivors

Although survival after congenital heart surgery is improving, patients who receive procedures for even mild defects have long-term mortality rates at least three times higher than their counterparts in the general population, according to a U.S.-based registry study published in the Journal of the American College of Cardiology.

Researchers linked data from the Pediatric Cardiac Care Consortium to National Death Index records to track mortality rates from 35,998 patients who had their first congenital heart surgery before turning 21 and were discharged alive from the hospital. After a median follow-up of 18 years, they found:

  • Individuals with congenital heart disease (CHD) died at a rate 8.3 times that of the general population. The 15-year standardized mortality ratio (SMR) dropped from 12.7 in the earliest period studied (1982 to 1992) to 10.0 in the latest era (1998 to 2003).
  • Women had a higher SMR (10.5) than men (7.2), but men had 30 percent higher mortality when excluding the first year after surgery.
  • There was marked variation in SMR based on the type of defect. “Mild” conditions such as atrial septal defect (ASD) and patent ductus arteriosus had SMRs of 3.1 and 3.4, respectively, while complete atrioventricular canal (CAVC) demonstrated an SMR of 17.0.
  • However, CAVC was associated with one of the most dramatic decreases in SMR, moving from 31.3 in the early era of the study to 15.3 in the late era. Dextro-transposition of the great arteries (11.0 to 3.8) and single-ventricle disease (53.7 to 31.3) were also associated with vast survival improvements in the later surgical era.

“This improvement may reflect the effect of improved diagnostic modalities, surgical techniques, and general supportive measures on the most vulnerable patients,” wrote lead author Logan G. Spector, PhD, with the department of pediatrics at the University of Minnesota, and colleagues. “Survival for simple lesions such as patent ductus arteriosus, ASDs, VSDs (ventricular septal defects) and pulmonic stenosis has reached a plateau, and even in the most recent era, still lags behind the survival of the general population. Survival for all other lesions continues to show incremental increase.”

The authors noted this was the largest study to date on long-term mortality after congenital heart surgery and includes a representative mix of cases and surgical results. However, demographic information was only available for a subset of patients, limiting the power of comparisons between races and ethnicities.

Despite the elevated mortality risk across the CHD spectrum, about 90 percent of patients survive 25 years, Spector et al. wrote.

“Our data from a large, multicenter U.S. cohort provide physicians, families, and patients with operated CHD nuanced information about expected long-term prognosis,” they wrote. “The persistently elevated risk of death after CHS emphasizes the need for close clinical monitoring of patients with even the mildest lesions to address residual morbidities and to understand the reasons for increased mortality in these patients who often have no residual hemodynamic abnormality. Because management differs between centers and evolves over time, continued analysis of lesion- and surgical strategy–specific outcomes may reveal differences in mortality that will inform current practice.”