Martin A. G. Lewin

Longitudinal stent fracture 11 months after implantation in the left pulmonary artery and successful management by a stent-in-stent maneuver.

Fracture of a 12 mm Palmaz stent after implantation in the left pulmonary artery for palliation of postoperative stenosis in a 9‐year‐old child is described. Successful management by implantation of a second Palmaz stent revealed immediate stabilization and no signs of significant restenosis during 1‐year follow‐up. Cathet Cardiovasc Intervent 2003;58:116–118.

Autonomic function testing in children and adolescents with diabetes mellitus

Abstract:  Cardiac autonomic neuropathy (CAN) is a common complication in type 1 diabetes mellitus (T1DM) and associated with an increased mortality. Early detection of CAN would be desirable for a better individual risk stratification. The aim of this study was to determine whether autonomic dysfunction can be diagnosed in young patients with a recent history of T1DM. Autonomic function was assessed in 20 pediatric patients with T1DM, aged 10–19 yr, and a control group of 136 non‐diabetic patients using four cardiorespiratory reflexes: heart rate and blood pressure response in standing position, deep breathing, and Valsalva maneuver. Furthermore, power spectral analyses of the low‐ and high‐frequency band of heart rate variability (HRV) and baroreflex sensitivity (BRS) were tested with the non‐invasive Task force monitor® (CNSystems, Graz, Austria). Cardiorespiratory reflexes were pathologic for at least one item in 75% of the diabetic and 60% in the healthy control group. A reduced BRS was always combined with abnormal HRV. We found this pattern in 30% of diabetic patients and never in the control group. In patients with impaired BRS, mean hemoglobin A1c (HbA1c) was 7.7% and duration of diabetes 6.5 yr. This did not differ from the overall value of the diabetic group: HbA1c level 8.4% and diabetes duration 7.3 yr. In conclusion, signs of autonomic dysfunction are not uncommon in an early stage of diabetes in young patients. Classical cardiorespiratory reflexes seem to be less specific than HRV and BRS as testing methods.

Successful management of a resistant renal artery stenosis in a child using a 4 mm cutting balloon catheter

Percutaneous transluminal renal angioplasty (PTRA) is a well‐established method to treat renal artery stenosis (RAS) in children and adults. However, a significant number of stenoses might not be treated by interventional techniques due to the inability to dilate the RAS. Conventional balloon angioplasty with a high‐pressure coronary angioplasty balloon at 20 atm was unable to dilate a significant RAS in a 12‐year‐old child with severe renovascular hypertension (RR 195/125 mm Hg). After using a 4 mm cutting balloon, we achieved wide patency of the renal artery and an instant normalization of blood pressure without further need of antihypertensive therapy. PTRA using the cutting balloon technique may offer an additional therapeutic option for selected patients in whom conventional balloon angioplasty was not able to dilate RAS. Cathet Cardiovasc Intervent 2002;56:227–231.

Successful management of an extreme example of neonatal hyperprostaglandin-e syndrome (bartter’s syndrome) with the new cyclooxygenase-2 inhibitor rofecoxib

Objective To describe the successful treatment of an unusual case of severe neonatal Bartter’s syndrome refractory to treatment with indomethacin. Design Case report, clinical. Setting Tertiary care intensive care unit. Patients A patient with neonatal hyperprostaglandin-E syndrome and excessive requirements of intravenous (via central venous catheter) water and salt supplementation, failure to thrive, vomiting, and massive growth retardation, despite adequate treatment with indomethacin. Main Result Four weeks after induction of the new cyclooxygenase-2 inhibitor rofecoxib, the patient was well, on full enteral feeds, thriving, and had gained 600 g in weight. A lower supplementary potassium, magnesium, and sodium intake was required. Reinstitution of indomethacin therapy resulted in severe deterioration, despite high indomethacin doses; symptoms improved again after rofecoxib administration. No side effects have been seen thus far. Conclusion This report shows that in selected patients with a severe form of neonatal Bartter’s syndrome, the new cyclooxygenase-2 inhibitor rofecoxib may control the clinical symptoms of hyperprostaglandin-E syndrome after ineffective indomethacin therapy.

Initial experience using the NuMED Cheatham Platinum (CP) stent for interventional treatment of coarctation of the aorta in children and adolescents.

Wir berichten über unsere ersten Ergebnisse bei der Behandlung der nativen oder residuellen Aortenisthmusstenose mit dem neuen Cheatham-Platinum (CP)-Stent. Die CP-Stents wurden bei 6 Patienten (mittleres Alter 12,7 Jahre) aufgrund einer Aortenisthmusstenose (5 native Stenosen, 1 Reststenose) implantiert. Der maximale systolische Druckgradient konnte von 49 auf 3 mmHg (p <0,001) verringert werden. Der mittlere Gefäßdurchmesser im Bereich der Aortenisthmusstenose erweiterte sich um 350% (von 3,8 auf 13,8 mm, p <0,01). Obwohl der maximale Durchmesser der Stents von 8 bis 18 mm variierte, kam es lediglich zu einer trivialen Verkürzung der eingesetzten Stents (max. 11%). Die Dilatation war bei allen Patienten erfolgreich und komplikationslos. Bei allen Patienten bestand vor der Intervention ein Hypertonus und drei Patienten wurden entsprechend antihypertensiv medikamentös therapiert. Bei 2 Patienten wurde auf eine maximale Gefäßdilatation während der initialen Implantation verzichtet, da der initiale Gefäßdurchmesser sehr gering war (ca. 1 mm). Bei diesen Patienten wurde eine erneute Dilatation nach Ablauf von 12 Monaten durchgefuhrt und die Stents auf Aortendurchmesser erweitert. Im aktuellen Beobachtungszeitraum von derzeit 18 Monaten sind 5 von 6 Patienten normotensiv und ohne Medikation. Hinweise für eine erneute Stenosierung, Dissektion, Aneurysmabildung oder Malposition der Stents ergaben sich bislang nicht. Die hier dargestellten Ergebnisse verdeutlichen, dass die neuartigen CP-Stents zur interventionellen Therapie von Aortenisthmusstenosen bei einem großen Spektrum unterschiedlicher Gefäßdurchmesser erfolgreich eingesetzt werden können. Somit stellt diese Therapie eine effektive Alternative zur Operation oder alleinigen Ballondilatation auch im Kindesalter dar. Die Möglichkeit der großzügigen Redilatation ohne wesentliche Verkürzung macht die CP-Stents besonders attraktiv für Patienten im Wachstumsalter. We report the immediate results in a group of selected patients with native or recurrent coarctation of the aorta who underwent endovascular stent implantation using the newly designed Cheatham-Platinum (CP)-stent. The balloon-expandable stents were implanted in 6 patients (mean age 12.7 years) with coarctation of the aorta (5 native, 1 recurrent). The maximal systolic peak pressure gradient was decreased from 49 to 3 mmHg (p <0.001). There was a 350% increase in the mean diameter at the original coarctation site (3.8 to 13.8 mm, p <0.01). Although the maximal diameter varied from 8 to 18 mm, there was only a minor reduction in the length of the CP-stents used (max. 11%). The dilatation was successful in all patients and there were no complications during balloon dilatation or stent implantation. All patients were hypertensive prior to stent implantation, with three of them requiring antihypertensive drug therapy. In 2 patients only a moderate dilatation diameter was chosen initially due to the extremely small coarctation site (1 mm) and repeat dilatation after 12 months was performed in order to obtain a maximal aortic diameter. At a mean of 18 months of follow-up, 5 of 6 patients are normotensive. There is no recurrence of coarctation, aortic dissection or aneurysm formation and no stent displacement. These findings suggest that the implantation of CP-stents for coarctation of the aortamay cover a wide spectrum of aortic diameters and consequently hereby offer an effective alternative approach to surgery or ballon dilatation alone even in infancy and childhood. The potential for redilatation of CP-stents in a wide range of diameters without significant shortening adds to the benefit of this device in growing children.

Aortic Aneurysm Rupture in Infantile Marfan's Syndrome

Abstract. A 3-year-old boy with early rupture of an aortic aneurysm due to infantile Marfans syndrome is presented. In an emergency operation we prepared a composite graft using a 17-mm St. Jude prosthesis with an 18-mm vascular conduit. The postoperative period was complicated by pneumothoraces, transient bilateral phrenic nerve paralysis, cerebral convulsion, and supraventricular tachycardia. Four months postop the composite graft was replaced with an aortic homograft due to severe stenosis. His condition after 12 months is excellent.

Percutanous closure of patent ductus arteriosus in small infants of less than 8 kg body weight using different devices

Therapeutic closure of patent ductus arteriosus (PDA) may become necessary in small infants with congestive heart failure refractory to medical management, regardless of the age or weight of the patients. Percutanous closure of PDA offers an alternative to surgical treatment [3,4]. The aim of this retrospective, multicentre observational trial was to evaluate the immediate results and mid-term clinical and echocardiographic follow-up of percutanous closure of PDA in young infants weighing less than 8 kg. Four centres were involved. Percutanous PDA closure was performed in 25 patients (16 female, 9 male) with a body weight of less than 8 kg (mean age 9.2 months, mean body weight 6.3 kg). The mean dimensions of the PDA were 5.9 mm at the aortic end and 2.7 mm at the pulmonary end with a mean of 2.2 mm at the narrowest part. Mean pulmonary artery pressure was 22.6 mm Hg, Qp:Qs = 2.2 to 1 and Rp:Rs = 0.13 to 1. Two patients had an additional atrial septal defect and one patient had an aorto-pulmonary collateral, which were closed during the same cardiac catheterisation (Table 1). Mean fluoroscopy time was 15.0 min. For a tubular shaped PDA, the preferred device was the pfm Ductocclud coil (pfm-AG, Cologne, Germany) or Cook detachable coils (Cook Inc., Bloomington, IN, USA). For a fenestrated PDA, the Amplatzer Duct Occluder (AGA Medical Corp., Golden Valley, MN, USA) was used. The PDA was closed according to standardised procedures [5]. The Amplatzer Duct Occluder (ADO) was used in 17 patients, Cook detachable coils in six patients, and the pfm Ductocclud coil in two patients (Table 1). In two patients (one with a body weight of 3.3 kg), percutanous PDA closure failed due to protrusion of the device into the aorta or left pulmonary artery; these infants successfully underwent surgical PDA closure (Table 1). Complete closure was achieved in all patients: immediate occlusion in 13 patients, the following day in four patients, and after mid-term follow-up (6 months) in six patients. In one patient, the Cook detachable coil migrated to the right pulmonary artery 1 day after the intervention; the coil was retrieved and the PDA was closed with an ADO (Fig. 1). In all patients, symptoms of heart failure resolved and medical treatment could be terminated. At mid-term follow-up (mean 18.8 months) Doppler echocardiography revealed mild flow velocity acceleration in the left pulmonary artery in two patients and in the descending aorta in one patient. Special attention was given to monitoring femoral vessel patency after catheterisation. There were no other complications (haematoma, femoral artery thrombosis, haemolysis, infection, haemorrhage or recanalisation). The rate of percutanous closure of PDA was comparable to other studies in small children of less than 10 kg body weight described by Aydogan et al. [1] (94%) or by Dalvi et al. [2] (90%), although we used other device types, depending on the morphology of the PDA. We conclude that percutanous closure of PDA is a feasible, safe and effective method in infants of between 4 and 8 kg body weight.

[Isolated myocardial noncompaction in childhood-case report and review of the literature].

The diagnostic work-up for the first syncopal episode of a 14-year-old female adolescent revealed the morphology of an isolated myocardial noncompaction on echography. Angiography and biopsy of the left ventricle confirmed the diagnosis. Despite a reduced shortening fraction (FS 21%) and frequent premature atrial beats, there were no further cardiac or extracardiac symptoms. After establishment of therapy with β-blockade, digitalis, angiotensinconverting enzyme inhibition and acetylsalic acid, the follow-up over 24 months was good; the implantation of an automatic implantable cardioverter-defibrillator is planned. Bei einer 14-jährigen jugendlichen Patientin wurde im Rahmen einer Synkopenabklärung in der Echokardiographie morphologisch das Bild einer isolated myocardial noncompaction nachgewiesen. Durch eine linksventrikuläre Angiographie und eine Herzmuskelbiopsie konnte diese Diagnose bestätigt werden. Neben einer verminderten linksventrikulären Verkürzungsfraktion (FS 21%) und zahlreichen supraventrikulären Extrasystolen zeigten sich keine weiteren kardialen oder extrakardialen Auffälligkeiten. Unter entsprechender medikamentöser Therapie (ACE-Hemmer, Digitalis, β-Blocker und ASS) war die Patientin über einen Nachbeobachtungszeitraum von 24 Monaten beschwerdefrei, die Implantation eines AICD ist geplant.

Common patterns of response to the head-up tilt test in children and adolescents.

Testing using the head-up tilt table is performed regularly as a diagnostic tool in the evaluation of syncope. Recommendations for protocols, and interpretation of the results, however, are mainly based on experience in adults. We evaluated the results of tilt table testing in 100 consecutive children and adolescents aged from 6 to 18 years and referred for investigation of syncope. Over half the patients, 55%, proved impossible to classify using the criterions established by the European Society of Cardiology. Based on our data, we propose a modified classification for responses to tilt table testing in the young.

Isolated myocardial noncompaction als seltene Ursache einer Synkope im Kindesalter

The diagnostic work-up for the first syncopal episode of a 14-year-old female adolescent revealed the morphology of an isolated myocardial noncompaction on echography. Angiography and biopsy of the left ventricle confirmed the diagnosis. Despite a reduced shortening fraction (FS 21%) and frequent premature atrial beats, there were no further cardiac or extracardiac symptoms. After establishment of therapy with β-blockade, digitalis, angiotensinconverting enzyme inhibition and acetylsalic acid, the follow-up over 24 months was good; the implantation of an automatic implantable cardioverter-defibrillator is planned. Bei einer 14-jährigen jugendlichen Patientin wurde im Rahmen einer Synkopenabklärung in der Echokardiographie morphologisch das Bild einer isolated myocardial noncompaction nachgewiesen. Durch eine linksventrikuläre Angiographie und eine Herzmuskelbiopsie konnte diese Diagnose bestätigt werden. Neben einer verminderten linksventrikulären Verkürzungsfraktion (FS 21%) und zahlreichen supraventrikulären Extrasystolen zeigten sich keine weiteren kardialen oder extrakardialen Auffälligkeiten. Unter entsprechender medikamentöser Therapie (ACE-Hemmer, Digitalis, β-Blocker und ASS) war die Patientin über einen Nachbeobachtungszeitraum von 24 Monaten beschwerdefrei, die Implantation eines AICD ist geplant.