Mirabile C, Mazzola A, Valeanu L, Lopez-Lopez V, Barbanti C, Biselli C, Hennequin C, Malekzadeh-Milani S, Bojan M. Postoperative B-type natriuretic peptide monitoring for the assessment of the magnitude of shunting through Blalock-Taussig anastomoses.
Int J Cardiol 2017;
249:151-155. [PMID:
28912041 DOI:
10.1016/j.ijcard.2017.08.075]
[Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/26/2017] [Revised: 08/11/2017] [Accepted: 08/30/2017] [Indexed: 11/18/2022]
Abstract
BACKGROUND
The Modified Blalock-Taussig shunt (MBTS) is the most common palliative operation performed in patients with complex cardiac defects. Postoperative morbidity and mortality rates are high, mainly due to shunt thrombosis and over-shunting. Over-shunting may be difficult to identify postoperatively based on conventional criteria. Since plasma B-type natriuretic peptide (BNP) concentrations correlate with the magnitude of shunting in various left-to-right shunt cardiac defects, we investigated its ability to identify postoperative MBTS over-shunting.
METHODS AND RESULTS
This retrospective, observational study included 42 consecutive patients (median age 9.50days, IQR: 6.00-58.25) undergoing MBTS for obstruction of the pulmonary blood flow at a tertiary referral pediatric cardiac center. The BNP threshold concentrations which accurately predicted outcome and MBTS over-shunting were derived using the ROC methodology. 443 BNP concentrations were analysed. The presence of atrio-ventricular valve regurgitation was the most important component of overall variance (72.75%). In 34 patients without regurgitation, BNP concentrations were predictive of a duration of mechanical ventilation >8days and of intensive care stay >11days, with ROC areas of 0.655 [0.597-0.719], 0.650 [0.589-0.711], a negative predictive value for the >1035pgmL-1 threshold of 0.93 and 0.96 respectively. SaO2 was less accurate for the prediction of both outcomes. In patients in whom the pulmonary flow was entirely MBTS-supplied, a BNP concentrations >1052pgmL-1 was predictive of a pulmonary-to-systemic ratio>2.
CONCLUSION
In MBTS patients without atrio-ventricular valve regurgitation, maintaining BNP below 1000pgmL-1 may represent a therapeutic target to avoid over-shunting.
Collapse