Ultrasound assessment of mesenteric blood flow in neonates with hypoplastic left heart before and after hybrid palliation.

BACKGROUND: Altered mesenteric perfusion may be a contributor to the development of necrotising enterocolitis in patients with hypoplastic left heart syndrome. The goal of this study was to document mesenteric flow patterns in patients with hypoplastic left heart syndrome pre- and post-hybrid procedure. METHODS: A prospective study on all patients with hypoplatic left heart syndrome undergoing the hybrid procedure was conducted. Doppler ultrasound analysis of the coeliac and superior mesenteric artery was performed. RESULTS: A total of 13 patients were evaluated. There was a significant difference in the coeliac artery effective velocity-time intergral pre- and post-hybrid procedure (8.69±3.84 versus 12.51±4.95 cm, respectively). There were significant differences in the superior mesenteric artery antegrade velocity-time integral pre- and post-hybrid procedure (6.86±2.45 versus 10.52±2.64 cm, respectively) and superior mesenteric artery effective velocity-time integral pre- and post-hybrid procedure (6.22±2.68 versus 9.73±2.73 cm, respectively). There were no significant differences between the coeliac and superior mesenteric artery Doppler indices in the pre-hybrid procedure; there were, however, significant differences in the post-hybrid procedure between coeliac and superior mesenteric artery antegrade velocity-time integral (13.8 2±5.60 versus 10.52±2.64 cm, respectively) and effective velocity-time integral (13.04±4.71 versus 9.73±2.73 cm, respectively). CONCLUSION: Doppler mesenteric indices of perfusion improve in patients with hypoplastic left heart syndrome after the hybrid procedure; however, there appears to be preferential flow to the coeliac artery versus the superior mesenteric artery in these patients post-procedure.

Comparing echocardiographic assessment of systolic function with catheterization data in patients with single right ventricles.

PURPOSE: Echocardiographic evaluation of systolic function in patients with single right ventricles (SRV) is important but remains challenging. Minimal data exist correlating echocardiographic indices with catheterization data in this population. The goal of this study was to evaluate which echocardiographic measurement correlated best with dP/dt (max) obtained by cardiac catheterization in SRV patients. METHODS: Patients with SRV physiology who underwent simultaneous echocardiography and cardiac catheterization were evaluated. Echocardiographic data included fractional area change % (FAC), displacement, TDI s'wave, myocardial performance index (MPI), global systolic strain, and global SR s wave. Maximum positive rate of ventricular pressure change measured as dP/dt (max) was obtained from the cardiac catheterization report. Correlations of echocardiographic and catheterization variables were examined using the Pearson correlation. RESULTS: Twenty-seven SRV patients were studied. Median age at the time of the catheterization was 11.4 months (range 0 - 132 months). dP/dt (max) values ranged from 337-1860 mmHg/s with a median of 994 mmHg/s. Mean FAC was 27.15 +/- 7.13%, displacement was 7.35 +/- 2.88 mm, TDI s' was 4.98 +/- 1.93 cm/sec, MPI was 0.41 +/- 0.17, global strain was-14.85 +/- 4.32%, and global SR s wave was -1.03 +/- 0.34 sec(-1). There were no significant correlations between dP/dt (max) and any of the echocardiographic measurements of systolic function in SRV patients. CONCLUSION: In patients with SRV physiology, catheterization-derived dP/dt (max) did not correlate with echocardiographic measurements of systolic function. Larger studies are needed to determine which non-invasive parameter best describes systolic function in patients with SRV.

Strain echocardiographic assessment of ventricular function after percutaneous pulmonary valve implantation.

INTRODUCTION: Percutaneous pulmonary valve implantation (PPVI) is an emerging therapy for pulmonary valve dysfunction. Minimal data on the midterm effects of PPVI on ventricular function exist. We describe the effects of PPVI on right and left ventricular (RV, LV) function with speckle tracking echocardiography. METHODS: Patients who met the inclusion criteria of the Food and Drug Administration Phase 1 Feasibility Clinical Trial PPVI were identified. Patients were studied with echocardiograms at baseline, post-PPVI (day of discharge), 3 months, and at 6 months. Patients were studied by cardiac magnetic resonance at baseline and at 6 months. Longitudinal strain was measured at the basal, mid, and apical portions of the RV, interventricular septum (IVS), and LV. Global RV and LV strain and strain rates were recorded. Paired t-tests were used for analysis. RESULTS: Ten patients were analyzed: nine patients were a variant of tetralogy of Fallot and one patient had complex LV outflow obstruction requiring a Ross and RV-pulmonary atresia conduit. Mean age was 24.4 ± 7.6 years. Indication for PPVI was pulmonary regurgitation in six patients, stenosis in two patients, and stenosis/regurgitation in two patients. After PPVI, both RV systolic pressure and RV to pulmonary artery pressure gradient significantly decreased. Cardiac magnetic resonance RV end-diastolic volume significantly decreased. IVS-mid, IVS-apical, and LV-global strain significantly increased and RV-basal decreased immediately after PPVI. Global RV a' strain rate significantly increased immediately after PPVI. However, RV, IVS, and LV strain/strain rate values between baseline and the 6 month echocardiographic study were either similar or significantly decreased. CONCLUSION: Despite improvement in RV hemodynamics, there was a decrease or no improvement in RV and LV function as measured by strain echocardiographic values at midterm follow-up. Larger studies with longer follow-up are needed to determine if these results remain consistent.

Assessment of in-stent stenosis in small children with congenital heart disease using multi-detector computed tomography: a validation study.

OBJECTIVES: Our purpose was to investigate the diagnostic reliability of multi-detector computed tomography (MDCT) in assessing in-stent stenosis compared to digital angiography (DA) in small children. BACKGROUND: Little is known about the feasibility of using MDCT to assess stents placed to treat children with congenital heart disease (CHD). METHODS: Twenty-two children (median age [range], 2(3/4) [(1/2) to 12] years) with 42 transcatheter placed stents (median diameter: 7.2 [3.4-16.3] mm) in the pulmonary arteries (n = 36), aorta (2), PDA (1), and SVC (3) underwent both MDCT and DA due to suspected hemodynamic problems. RESULTS: Independent "blinded" observers were able to measure stent and minimal luminal diameters in 115 out of 124 (93%) stent segments on MDCT and DA. The interobserver variability was low (mean difference: 0.5, SD 0.8 mm) with high correlation (r = 0.97; P < .0001). The percent stenosis by MDCT correlated well with DA (r = 0.89, P < .0001; mean error 2.7, SD 10.4%). For all grades of stenosis, the sensitivity and specificity for MDCT were 58% and 97%, respectively. At a threshold of approximately > or =20% stenosis sensitivity became >98%. All stent associated complications [fracture (4), vascular narrowings (11)] were diagnosed by MDCT. As the stent diameter increased, there was significantly reduced variability between MDCT and DA for in-stent stenosis (P < .0001). CONCLUSION: In small children, MDCT is a feasible and promising method for assessing stent associated complications in the treatment of CHD. Cardiac surgeons and interventional cardiologists might rely on this imaging modality to plan specific interventions more precisely and to assess the results upon follow up.