Davide Marini

Safety and Accuracy of 64-Slice Computed Tomography Coronary Angiography in Children After the Arterial Switch Operation for Transposition of the Great Arteries

OBJECTIVES We investigated the accuracy of 64-slice computed tomography (CT) angiography, as compared to invasive angiography, to evaluate reimplanted coronary arteries in children after arterial switch operation (ASO) for transposition of the great arteries (TGA). BACKGROUND Assessment of the integrity of reimplanted coronary arteries is crucial for long-term outcome after ASO for TGA. Noninvasive tests have limited accuracy for detecting significant coronary lesions, and invasive coronary angiography is usually required in this setting. METHODS One hundred thirty consecutive children, after ASO for TGA (age 5.6 +/- 1.1 years), underwent conventional invasive coronary angiography and coronary CT angiography using a 64-slice scanner. The ability of CT to detect significant coronary stenoses (>30% diameter reduction) of the coronary ostia and proximal segments, and other abnormalities of the coronary arteries was analyzed by blinded comparison to the invasive coronary angiogram. RESULTS The CT was fully evaluable in 126 of 130 patients (97%), allowing assessment of ostia and proximal segments of all coronary arteries. The CT correctly detected all 12 patients (9.2%) in whom invasive coronary angiography had identified significant coronary lesions, with a sensitivity, specificity, and negative predictive value of 100%. In addition, CT showed nonsignificant coronary lesions (<30% luminal narrowing) in 6 patients and allowed determination of the underlying reasons for coronary luminal narrowing, such as stretching or compression of the re-implanted coronary arteries caused by their anatomic relationship to the adjacent great vessels. CONCLUSIONS 64-slice CT coronary angiography performs as well as invasive angiography for detecting significant coronary lesions in the majority of children who have undergone the arterial switch procedure for TGA. CT also provides information on the underlying mechanism of coronary luminal narrowing.

Acute angulation of the aortic arch predisposes a patient to ascending aortic dilatation and aortic regurgitation late after the arterial switch operation for transposition of the great arteries

OBJECTIVE We assessed the contribution of acute aortic arch angulation and enhanced systolic pulse wave reflection to dilatation of the ascending aorta and aortic regurgitation late after the arterial switch operation for transposition of the great arteries. METHODS We performed aortography, radial artery applanation tonometry, and transthoracic echocardiography in 47 children (aged 5-6 years) who underwent the arterial switch operation and in 20 matched healthy controls. The aortic arch angle, ratio of ascending/descending aortic diameter, degree of aortic regurgitation, central pulse pressure, aortic augmentation pressure, and augmentation index were measured. RESULTS The aortic arch angle was more acute (55 +/- 6.5 degrees vs 68 +/- 5 degrees, respectively, P < .001) and the ratio of the ascending/descending aorta diameter was significantly greater (1.98 +/- 0.4 vs 1.55 +/- 0.06, respectively, P < .001) in the patients who underwent the arterial switch operation compared with controls. Augmentation pressure and augmentation index were higher in the patients who underwent the arterial switch operation than in controls (7.5 +/- 4.6 vs 3.4 +/- 5.8, respectively P = .04; 21 +/- 10 vs 8 +/- 13, respectively, P = .005). A more acute aortic angle was associated with a higher aortic augmentation index (r = 0.41, P < .01), a greater ratio of the ascending to descending aorta (r = -0.6, P < .001), and the degree of aortic regurgitation (r = 0.39, P < .01). CONCLUSION Sharper angulation of the aortic arch is associated with early pulse wave reflection, dilatation of the ascending aorta, and aortic regurgitation late after the arterial switch operation for transposition of the great arteries.

Closure of extracardiac Fontan fenestration by using the covered Cheatham Platinum stent

Objective: The purpose of this study was to describe our experience concerning the use of covered Cheatham Platinum (CP) stent in patients with fenestrated total cavopulmonary connection (TCPC). Background: Closure of TCPC fenestrations has been achieved by utilizing different devices designed to close intra‐cardiac or aorto‐pulmonary communications. Methods: We used the covered CP stent in 6 patients with fenestrated TCPC. Median age and weight were 11 years and 38 Kg, respectively. Femoral approach was used in all but 1 patient having bilateral thrombosis of femoral veins. The CP stent was crimped on a BiB balloon in 5 patients and on a simple balloon in 1 patient. The balloons diameter was the same size or 1–2 mm larger than the TCPT conduit, according to angiographic diameter. Results: Mean procedural and fluoroscopy time were 41 ± 8 and 8 ± 2 min, respectively. Immediate full occlusion of fenestration was obtained in all patients. Mean central venous pressure was not significantly increased from 10.8 ± 2.5 to 11.8 ± 2.8 mm Hg and oxygen saturation significantly increased from (91.5 ± 4.4)% to (98.5 ± 1.9)% (P = 0.003). No procedural or intra‐hospital complications occurred. In particular, no arrhythmias, systemic embolism, or acute venous thrombosis were observed. At a median follow‐up of 2.8 months all patients have normal oxygen saturation and are symptom‐free. Conclusions: The covered CP stent can be easily and effectively used for closure of TCPC fenestrations. This method has the advantage to avoid protrusion of prosthetic material into the left atrium and to prevent early or late embolism.

Fontan circulation causes early, severe liver damage. Should we offer patients a tailored strategy?

BACKGROUND In patients with Fontan circulation, the liver is profoundly affected by chronic venous stasis. Little is known about early hepatic changes in this population. METHODS We performed echocardiography, abdominal ultrasound, liver elastography, cardiac catheterization, esophago-gastro-duodenoscopy and calculated MELD-XI score in 64 Fontan patients (69% minors), at an interval of 1-15years since Fontan. RESULTS Cardiac output remained stable in the first 5years after Fontan, then significantly decreased (r=-0.45, p(r=0)=0.003). NYHA class significantly increased after Fontan. Patients in NYHA class II/III (n=21, 14 minors) had significantly higher hepatic pressures, but normal ventricular function and pulmonary vascular resistances (PVR). Patients with pulmonary arterial pressure (PAP) ≥15mmHg (n=12, 6 minors) and those with PVR≥2WU*m(2) (n=27, 25 minors), had higher hepatic pressures (p<0.0001), a higher incidence of liver collaterals and/or esophageal varices (p<0.0001) and splenomegaly (p<0.02). Liver stiffness (LS) was elevated in most patients (median, 25th-75th percentile:17.3KPa, 14.1-21.4). It rapidly increased during the first 5-years after Fontan, compared to the following 5-years (from 12.2KPa, 9.8-14.1 to 17.5KPa, 14.3-24.5, p=0.007), then remained stable (19.1KPa, 16.9-22.6, p=0.60). MELD-XI score increased linearly with the time interval since Fontan (r=0.31, p(r=0)=0.01). For patients above 12years we found a linear correlation between LS and MELD-XI score in the 6-15years period after Fontan (r=0.40. p(r=0)=0.04). The overall incidence of established liver cirrhosis was 22%. CONCLUSIONS This is the largest study showing that Fontan circulation prompts early, progressive and eventually irreversible liver damage. Precautions should be taken immediately after Fontan, to protect this fragile population.

Left coronary to right ventricle fistula in a child: management strategy based on cardiac-gated 64-slice CT

Congenital coronary fistulae are a diagnostic challenge. A prerequisite for best management is accurate anatomical evaluation, traditionally provided by invasive catheter angiography. Multislice CT (MSCT) is an emerging noninvasive technique for coronary artery evaluation. We present a 3-year-old boy and highlight the clinical usefulness of new-generation MSCT to study coronary artery fistulae in children. Multiplanar and 3-D reconstruction offer invaluable information to plan the best therapeutic strategy in this setting. We provide evidence for the expanding clinical role of MSCT for coronary artery imaging in children.

From bare to covered: 15-year single center experience and follow-up in trans-catheter stent implantation for aortic coarctation.

Bare stents has become the first line therapy for aortic coarctation. Covered stents has been reported more recently in clinical practice.

Midterm results of percutaneous closure of very large atrial septal defects in children: role of multislice computed tomography

AIMS The aim of this study was to assess the midterm results of percutaneous closure of very large atrial septal defects (ASD) in children with transthoracic echocardiography (TTE) and multislice computed tomography (MSCT). METHODS AND RESULTS Among 142 children who underwent percutaneous ASD closure with the AMPLATZER® Septal Occluder (ASO) (AGA Medical Corporation, Plymouth, MN, USA) during an eight year period, 51 patients with very large defects, were evaluated by TTE and MSCT after a period of at least two years following ASD closure. Median age at ASD closure was six years (range 4-10), with mean ASD size 20.9±2.9 mm. Median device size was 20 mm (range 15-26) and median device: septal length ratio 0.95 (range 0.8-1). Early complications included one transient complete atrioventricular block and one device embolisation. At a median follow-up of 55 months (range 25-92) all patients were clinically asymptomatic and had a normal ECG. TTE did not demonstrate device protrusion across the lumen of either the systemic or pulmonary veins. The mean device: septal length ratio had decreased from 0.96±0.05 to 0.8±0.02 (p<0.001). There was good correlation between the measure of atrial septum length by TTE and MSCT (r: 0.79, p<0.001). MSCT identified moderate dynamic device protrusion into the lumen of systemic or pulmonary veins in five patients and partial device malpositioning in two patients. CONCLUSIONS Occlusion of very large ASD in children can be performed with low complications rate. MSCT provides detailed information regarding the location of the device with respect to surrounding anatomic structures and reveals anomalies not evident by TTE.

Anaemia is a predictor of early death or cardiac transplantation in children with idiopathic dilated cardiomyopathy

INTRODUCTION The aim of our study was to establish the prevalence and the prognostic value of haematological abnormalities in children with cardiac failure. PATIENTS AND METHODS A series of 218 consecutive children with a first diagnosis of idiopathic dilated cardiomyopathy were retrospectively examined. Haematological evaluation was performed at first diagnosis. Death or cardiac transplantation was the main outcome measure. RESULTS The median age was 0.6 years, ranging from 1 day to 15.8 years and median follow-up was 2.65 years, ranging from 0 to 17.2 years. After a median interval of 0.2 years, ranging from 0 to 8.7 years, 56 patients died and 25 were transplanted. Event-free survival at 1 and 5 years was 68% (95% confidence interval, 63-75%) and 62% (95% confidence interval, 56-69%). Blood levels of haemoglobin less than 10 grams per decilitre, urea over 8 millimoles per litre, and C-reactive protein over 10 milligrams per litre were found in 24%, 20%, and 24% of patients, respectively. The log-rank test showed that haemoglobin (p = 0.000) and C-reactive protein (p = 0.021) were predictors of death or transplantation. In the multivariate Cox model, haemoglobin (hazard ratio = 0.735; confidence interval = 0.636-0.849; p = 0.000) and urea (hazard ratio = 1.083; confidence interval = 1:002-1:171; p = 0.045) were predictive of poor outcome. Cubic spline functions showed that the positive role of haemoglobin on survival was linear for values less than 12 grams per decilitre and null for values more than 12 grams per decilitre. Adaptive index models for risk stratification and Classification and Regression Tree analysis allowed to identify the cut-off values for haemoglobin (less than 10.2 grams per decilitre) and urea (more than 8.8 millimoles per litre), as well as to derive a predictor model. CONCLUSIONS In children with idiopathic dilated cardiomyopathy, anaemia is the strongest independent prognostic factor of early death or transplantation.

Cheatham Platinum (CP) and Palmaz stents for cardiac and vascular lesions treatment in patients with congenital heart disease

AIMS To compare Cheatham Platinum (CP) stent and Palmaz stent for the treatment of native and postoperative lesions of congenital heart disease (CHD) patients. METHODS AND RESULTS From January 1998 to December 2007, 96 CP stents and 77 Palmaz stents were implanted in 89 and 64 CHD patients. All stents could be deployed. Decrease in pressure gradient was higher with the CP than with the Palmaz stent (36.1 +/- 23 and 23.4 +/- 18.3 mmHg, p = 0.004). The procedure was more often successful with a CP than with a Palmaz stent (96% and 88% of patients, p = 0.03). Stent-related complications were more rarely observed with the CP than with the Palmaz stent (9% and 27%, p = 0.007). The incidence of vascular dissection was lower with CP than with Palmaz stent (1% and 6%), the incidence of stent migration was similar in the two groups (8% and 6%). Balloon burst, never observed in the CP stent group, was frequent in the Palmaz group (0% and 11%, p = 0.001). There were no procedural deaths. The need for urgent surgery was similar in the two groups (2% and 1%). CONCLUSIONS Our findings show a superiority of the CP over the Palmaz stent concerning efficacy and reduction of complications rate for the treatment of cardiac and vascular lesions of children and young adults with CHD.

Interventional Catheterization after Total Cavopulmonary Connection: Experience in 68 Patients

BACKGROUND  Total cavopulmonary connection (TCPC) is performed in patients having a single ventricle to allow the passive flow of systemic venous blood to the lungs. Interventional catheterization is needed to treat residual defects or complications. AIMS  We discuss our results concerning 68 patients who had had TCPC from January 1995 to December 2010. METHODS Initial and follow-up catheterization data were reviewed retrospectively. Mid-term results were evaluated by means of angiography and/or CT scan. RESULTS  Mean age at TCPC was 5 years (2.5-18); mean interval between TCPC and catheterization was 5.6 years (1.5-15). Sixty-nine catheterizations were performed in 53 patients. Eleven patients (21%) had low venous pressure, did not display a right-to-left shunt, and did not need any intervention. Fifteen patients (28%) had low venous pressure and only needed the closure of the fenestration. The remaining 27 patients (51%) needed the following interventions: embolization of venous vessels prompting right-to-left shunt (n = 15), stenting or reconnection of pulmonary arteries (n = 5), stenting or recanalization of systemic veins (n = 11), other procedures (n = 5). In 3 patients the fenestration could not be closed due to high venous pressure. After the interventions oxygen saturation increased from 90.5%± 4.8% to 94.7% ± 3.6% (P = 0.002). CONCLUSIONS Our data show that 49% of patients with TCPC are in good condition late after surgery. However, half of these patients continue to need interventions generally aimed at suppressing stenoses at various levels of TCPC or at occluding vessels prompting right-to-left shunt. This population should enter a multicenter program aimed at identifying patients at risk.