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In this issue of the Journal of Cardiac Surgery , van de Woestijne
and colleagues1 describe their experience with
“consistent” staged unifocalization through a lateral thoracotomy in
patients with pulmonary atresia, ventricular septal defect, and major
aortopulmonary collateral arteries (PA/VSD/MAPCA). Over the past 30
years they have applied this strategy in 39 consecutive patients.
Thirteen of the 39 patients underwent a central shunt operation to
promote growth of a confluent, hypoplastic central pulmonary artery
prior to unifocalization. The median age at the first unifocalization
was 13 months. In their initial experience, they performed the first
unifocalization at a mean age of 5.9 years but evolved to earlier
intervention with their current practice being to perform the first
unifocalization procedure at the age of 1 year. A total of 66
unifocalization procedures were performed with two early mortalities.
Definitive repair was performed in 76.3% eligible patients (29/38,
excluding one patient awaiting definitive repair) with one hospital
death (3.4%) and another patient requiring opening of a VSD. Seven
patients were left palliated after unifocalization procedures. Four of
the seven patients passed away during the follow-up. The overall
survival after the definitive repair was 96% at 20 years with a median
follow-up of 19 years. Among survivors after definitive repair, all but
one were in New York Heart Association Class 1 or 2 at follow-up.
Freedom from pulmonary artery intervention after definitive repair was
71%, 67% and 67% at 5, 10 and 15 years, respectively. The authors
concluded that their staged approach was a reasonable strategy for most
PA/VSD/MAPCA patients.
This article is unique in that it describes a “consistent” staged
thoracotomy unifocalization approach to PA/VSD/MAPCA patients in the
current surgical era, a strategy that predominated in the earlier
surgical eras. Puga and colleagues2 reported their
experience utilizing this approach. From 1982 to 1987, 60.5% (23/38) of
their patients reached definite repair with one early and one late
death. Eight patients were still awaiting further unifocalization
procedures. The mean intraoperative right ventricular/left ventricular
pressure ratio (pRV/pLV) at the definitive repair was 0.63. Iyer and
colleagues3 published their experience with 58
patients from 1979 to 1989. 51.7% (30/58) of the patients reached
definite repair with one early and 3 late deaths. Ten patients were
still awaiting further unifocalization procedures, and 12 other patients
were deemed unsuitable for definite repair after unifocalization
procedures. Ishibashi and colleagues4 published their
recent experience with staged thoracotomy unifocalization in 2007. In
their experience with 113 consecutive PA/VSD/MAPCA patients from 1982 to
2004, definitive repair was performed in 80.5% (91/113) with 5 early
and 15 late deaths. From these studies, one could speculate that the
results of a staged unifocalization strategy toward definitive repair
have been improving over time. The current article definitely supports
this with definitive repair completion in 76.3% of the patients and an
overall survival after definitive repair of 96% at 20 years despite the
study period ranging from 1989 to the present. This improvement could be
attributed to early recruitment of patients and advanced surgical
techniques, such as using autologous tissue where possible and
performing intrapulmonary anastomoses to avoid long segments of
remaining MAPCAs.1,4
Despite the seeming improvement, the staged unifocalization strategy has
not been the dominant option over the past 20 years primarily due to the
introduction of midline one-stage complete unifocalization by Reddy et
al5 in 1995. The Stanford group has adopted and
advocated for midline unifocalization in patients with predominantly
single-supply MAPCAs. According to the data of 307 patients who
underwent their initial procedures at Stanford from 2001 to
20176, 78.5% (241/307) patients were treated with the
midline unifocalization strategy with 84.6% (204/241) of them
undergoing single-stage definitive repair with a mean pRV/pLV of 0.36.
Overall, 93.0% (280/301) of their eligible patients achieved definitive
repair. Staged thoracotomy unifocalization was performed in only 2
(0.7%) of their patients. In their experience, unifocalization revision
was necessary for 18.4% of the patients who underwent the midline
unifocalization.7
Another strategy in these patients that has been promoted by the
Melbourne group over the past 20 years is pulmonary artery
rehabilitation without unifocalization.8 This concept
stemmed from a review of their own patients who had the staged
unifocalization strategy.9 Recently, they reported
their experience from 2003 to 2014.10 Among 37
patients, 11% (4/37) of the patients with heart failure and large
MAPCAs underwent one-stage definitive repair with unifocalization. Among
30 eligible patients who entered into the pulmonary artery
rehabilitation strategy, 73.3% (22/30) of the patients reached
definitive repair, whereas failure of the strategy occurred in 5
patients who either needed unifocalization procedures or were left
palliated. Overall, 76.5% (26/34) of their eligible patients reached
definitive repair. A lesson from these institutions where either midline
one-stage complete unifocalization or the pulmonary artery
rehabilitation strategy was sought aggressively is that there is no
one-fits-all solution because of the heterogeneous morphology of
pulmonary arteries and MAPCAs in these patients.
Weaknesses of the article by van de Woestijne and
colleagues1 are a small number of patients over a long
(30 years) study period, thereby making it impossible to perform
sub-analyses, such as comparison between surgical eras or an analysis of
results depending on the anatomy of pulmonary arteries and MAPCAs. In
addition, information on intraoperative pRV/pLV at definitive repair and
at follow-up, a critical benchmark for the management of patients with
PA/VSD/MAPCA, is absent.
In conclusion, van de Woestijne and colleagues1present a successful staged thoracotomy unifocalization approach to
PA/VSD/MAPCA. Given the multiple variations one could have with
pulmonary artery and MAPCA anatomy in this anomaly, a midline
unifocalization approach may not always be possible. It behooves the
surgeon to be familiar with the lateral thoracotomy unifocalization
staged approach to PA/VSD/MAPCA.