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Page 6 of 18 Zimmermann et al. Vessel Plus 2019;3:31 I http://dx.doi.org/10.20517/2574-1209.2019.010

asymptomatic patients, those whose pulmonary artery pressure is less than 50 percent systemic arterial
pressure, and pulmonary vascular resistance is greater than one third the peripheral vascular resistance,
without exercise induced cyanosis, are recommended for ASD closure [40-42] .

Of great interest to clinicians in the age of readily available transcatheter repair of secundum type ASDs
is the decision to pursue transcatheter or open surgical repair. One such study at Mayo Clinic sought to
evaluate outcomes of surgically managed ASD cases as compared to medical management alone with a
follow-up interval of 27 to 32 years after the index surgery. Study findings demonstrated that the survival
rate was 74% as compared to 85% for age sex matched medically managed controls. In cases where surgical
intervention occurred below the age of 24 years, survival rate reported was the same as age matched
controls. Independent predictors of long-term survival were age at the time of operation and main
[43]
pulmonary artery systolic Pressure (PASP) . The more recent study of the Danish population found that
there was a significant reduction in the life expectancy and lower quality of life in patients with small ASDs
[44]
that did not meet criteria for repair when compared to the general population . In another study, surgical
vs. medical management were compared prospectively in a randomized clinical trial of 473 patients over
the age of 40 years with a median follow up period of 7.3 years. Overall mortality rate was not statistically
different. However, there was a higher rate of recurrent pneumonia noted in the medical arm. There was
indeed a trend higher complication rates such as CHF, sudden cardiac death, and overall mortality in the
[45]
medical arm, but was ultimately not statistically significance .
More recently the 2018 ACC/AHA task force undertook a meta-analysis seeking to understand differences
in outcomes of medical vs interventional management of secundum type ASDs. Their analysis found 11
studies that met criteria for inclusion, and in most instances found a protective effect with bearing on
reduction of symptoms, functional capacity, and improvement of hemodynamic characteristics following
[46]
either surgical or transcatheter intervention . Interestingly, in the same analysis, there was either
insufficient data to determine relative risk of death, or a weakly positive protective effect after intervention,
from the included studies. Furthermore, a nationwide study of patients with corrected and uncorrected
ASDs were compared to the general population with interesting results; their findings demonstrated
a relative reduction in mortality for patients who underwent repair of ASDs. But whether repaired or
[47]
not, patients with ASDs patients experienced a shorter lifespan when compared to the general public .
Taking the results of these, and similar studies, may help establish important expectations when discussing
intervention; quality of life and reduction of symptoms, rather than preventing mortality, may lead
discussions pertaining to goals of therapy.

Surgical vs. transcatheter intervention
At the time of this writing, only secundum type defects have transcatheter devices approved for
intervention. Primum, Sinus Venosus, and Coronary sinus defects still carry the recommendation of open
surgical intervention with only rare reports of transcatheter interventions published [48-51] . In the pediatric
population there are similar long term outcomes between surgical vs. transcatheter intervention, however
cost analysis demonstrates a better value in terms of overall cost as well as shorter length of stay for patients
[52]
undergoing transcatheter repair . In the adult population, mortality between transcatheter and surgical
intervention are similar, but long-term reintervention rates appear to vary between the two. In a review of
[53]
718 procedures, Kotowycz et al. report that long term reintervention rates for transcatheter repair are
more common than compared with conventional surgical approach. Other studies report similar findings -
but prospective randomized studies have not been undertaken to determine true differences. Furthermore,
patients more likely to undergo transcatheter repair are often higher risk than patients deemed appropriate
for surgical intervention potentially skewing attempts to study differences in outcomes.

Of growing interest is the prospect of treating ASDs associated with sinus venosus defects, which are
traditionally treated with open surgical repair. Presently, there are only case reports describing transcatheter