Ann Thorac Surg 2005;79:1098-1099
© 2005 The Society of Thoracic Surgeons
a Department of General Pediatrics, Westfaelische Wilhelms-Universitaet Muenster, Albert-Schweitzer-Strasse 33, D-48129 Muenster, Germany
To the Editor:
Ungerleider and colleagues  presented promising data on their concept of routinely placing neonates with hypoplastic left heart syndrome (HLHS) on a ventricular assist device (VAD) postoperatively after a stage-one Norwood procedure. The authors suggested that prophylactic use rather than rescue use of a VAD or extracorporeal membrane oxygenation (ECMO) might result in a better outcome after this procedure.
To prove this hypothesis, two vital questions need to be answered: What is the expected early postoperative morbidity and mortality using conventional therapy? What are the additional risks of an extended period of mechanical circulatory support in neonates, in particular concerning the neurologic outcome? The authors could answer the first question by comparing their results in patients with HLHS before use of the VAD with published results from major centers [2, 3]. Taking into account a risk stratification for HLHS as reported in the February 2004 issue of The Annals by Checchia and co-workers  would facilitate comparison of results between centers.
As for the second question, on the basis of our experience, we share the concern of Dr Austin  that proper anticoagulation is still an unsolved issue in neonates and young infants. It is noteworthy that in the UK Collaborative ECMO Trial , 29% of patients in the ECMO arm showed abnormalities on cranial ultrasound after trial entry. Other groups [6, 7] found a 15% incidence of intracranial hemorrhage or infarction after neonatal ECMO. In 2002, the overall mortality rate for rescue ECMO in patients with congenital heart disease was 62%; it was 73% in the stage-one Norwood subgroup . The number of reports on neonatal VAD use is small, but hemostasis-related complications are again a major concern [9, 10]. Hence, serious side effects of prolonged mechanical circulatory support must be anticipated.
The report of Ungerleider and associates lacked detailed data on the morphological and functional status of the patients. Normal perioperative head ultrasound examinations do not exclude infarctions and later atrophy of the brain. Eight of 13 patients in their study received neurologic follow-up, which corresponds to a drop-out rate of 38% in that subgroup, which was not explained. There was no control group.
In light of this scenario, it seems premature to routinely place all patients who undergo a stage-one Norwood operation on a prolonged period of VAD use, as only a subgroup will need this expensive and potentially harmful therapy. It is unclear whether the expected benefit for that subgroup justifies the additional risk to infants in hemodynamically stable condition who could be expected to have a reasonably good outcome without a VAD [2, 3].
Small numbers, the apparent lack of background details, and the design of the study lead us to strongly endorse the suggestion of Ungerleider and associates to collect and report data "in a randomized, comparative manner."
We congratulate Ungerleider and colleagues on their excellent results and believe absolutely that this promising approach merits cautiously conducted controlled studies with sufficient numbers of Norwood procedures. In the meantime, it would be good practice not to use treatment strategies that have not yet been validated.
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