Ventricular fibrogenesis activity assessed by serum levels of procollagen type III N-terminal amino peptide during the staged Fontan procedure.

OBJECTIVE: We tested the hypotheses that volume overload and cyanosis observed in the pre-Fontan single ventricular circulation are associated with increased ventricular fibrogenesis, that the Fontan procedure helps to reduce fibrogenesis, and that persistently increased fibrogenesis in the Fontan ventricle is associated with ventricular diastolic dysfunction. METHODS: Levels of serum amino-terminal procollagen type III, a marker of tissue fibrogenesis, were measured in 172 patients with single ventricle circulation and 149 controls. Patients were divided into 3 groups according to surgical stage: 59 patients after Blalock-Taussig shunt or pulmonary banding, 60 patients after Glenn surgery (Glenn group), and 53 patients after Fontan surgery (Fontan group). RESULTS: Serum amino-terminal procollagen type III levels were significantly higher among the 3 single ventricle groups than among control patients, but decreased with each surgical stage (0.604, 0.176, 0.143, and 0.073 U/mL, for Blalock-Taussig shunt or pulmonary banding, Glenn, Fontan, and controls, respectively). Severity of volume load and cyanosis were independent determinants of increased amino-terminal procollagen type III levels in patients before Fontan surgery, and persistently increased amino-terminal procollagen type III after Fontan surgery was associated with ventricular diastolic stiffening (r = 0.494, P = .009). Data also indicated close associations between amino-terminal procollagen type III levels and activation of the renin-angiotensin-aldosterone system, suggesting potential involvement of this hormonal system in the increased fibrogenesis after Fontan surgery. CONCLUSIONS: These results suggest that serum amino-terminal procollagen type III may provide important diagnostic information on myocardial fibrosis in patients with single ventricle circulation and raise the possibility that ventricular fibrogenesis may be a potential therapeutic target in this population.

Impact of novel balloon catheter on static balloon atrial septostomy with double balloon technique in infants with congenital heart disease.

BACKGROUND: The aim of this study was to investigate the feasibility of static balloon atrial septostomy (BAS) with the double balloon technique for infants. TMP PED balloon catheter, newly designed for static BAS in small children, was used in 3 infants. The balloon catheter has a low profile, short and round shoulder, and smooth deflation without slippage. METHODS AND RESULTS: Three infants (transposition of the great arteries, n=2; pulmonary atresia with intact ventricular septum, n=1) underwent static BAS with double balloon for restrictive interatrial communication between December 2014 and March 2015. Hemodynamic and echocardiographic assessment was done before and after the procedure. Pressure gradient between left and right atrium decreased from 6, 7 and 9 mmHg to 2, 2 and 1 mmHg, respectively. Oxygen saturation in systemic artery increased from 72, 68 and 73% to 78, 70 and 79%, respectively. Maximum defect diameter increased from 3.5, 3.0 and 3.3 mm to 6.6×5.2, 9.0×6.2 and 8.1×5.1 mm, respectively. No complication was recorded. CONCLUSIONS: Static BAS with double balloon technique using the novel TMP PED balloon catheter was safe and effective in producing sufficient interatrial communication for 8-20 weeks in infants. Static BAS is a promising procedure to create interatrial communication in infants.

Troponin I levels in extracorporeal membrane oxygenation following congenital heart surgery.

BACKGROUND: Correlating postcardiotomy extracorporeal membrane oxygenation (ECMO) troponin I (TnI) levels and outcomes. METHODS: Between January 2006 and August 2010, 34 patients needed postcardiotomy ECMO for low cardiac output. Bailout ECMO was required either after unsuccessful weaning from bypass (n = 17, 50%), postoperatively from prolonged hemodynamic failure (n = 8, 23.5%), or following resuscitation (n = 9, 26.5%). The TnI levels were measured following surgery or resuscitation during 10 days and compared between survivors (group I) and non-survivors (group II). RESULTS: Median support duration was seven days (range: 0-31). Surgery involving hypoplastic aortic arch repair (Norwood palliation; n = 7, 20.6%, or biventricular repair; n = 11, 32.4%) led to most ECMO runs. Successful weaning from ECMO and hospital survival were 76.5% and 50%, respectively. In group I, peak TnI levels were reached by 24 hours postoperatively, comparable to levels in group II (36 ± 34 vs 49 ± 38 ng/mL; P = .98). However, in group II, TnI levels formed a plateau by the second postoperative day, whereas group I showed a steep decline in TnI levels, suggesting myocardial recovery (P = .028). All patients (n = 4) who reached or maintained peak TnI levels at 48 hours died. On days 8, 9 and 10, TnI levels were significantly higher in group II (P = .024, .019, and .013, respectively). CONCLUSIONS: Postcardiotomy ECMO was most commonly required after aortic arch repair. In the absence of ongoing myocardial insult due to ECMO hardware issues, coronary insufficiency or residual lesions, plateau TnI levels at 48 hours may seem to indicate an unfavorable outcome due to irreversible myocardial damage.

Regression of cardiac enzyme and ventriculocoronary communication in an infant with pulmonary atresia and intact ventricular septum after radiofrequency valvulotomy and valvuloplasty.

I report on a 3-month-old infant with pulmonary atresia-intact ventricular septum and ventriculocoronary communication (VCC) who underwent percutaneous radiofrequency valvulotomy and valvuloplasty (RFVV). The patient's cardiac troponin-I, creatine kinase (CK), and myocardial fraction of (CK-MB) were elevated before RFVV and were gradually regressed to normal levels 12 days after RFVV. The VCC disappeared after RFVV. The transvalvular pressure gradients across the pulmonary valve were less than 30 mmHg in the follow-up echocardiography at 4-12 months of age. Oxygen saturation was approximately 90% in room air. Dipyridamole-thallium myocardial scintigraphy showed positive reperfusion over the apex and interventricular septum.