Thomas Krasemann

Hybrid procedure as an alternative to surgical palliation of high-risk infants with hypoplastic left heart syndrome and its variants

OBJECTIVES Despite improvements in the surgical management of neonates with the hypoplastic left heart syndrome and its variants, there is a subset of children who have a high predicted mortality. We have analyzed and report our results with the hybrid approach in the management of these high-risk patients. METHODS Children identified by our selection criteria underwent the initial hybrid procedure performed in the catheterization laboratory. This consists of surgical banding of the branch pulmonary arteries and stenting of the arterial duct. This was followed 3 to 6 months later by the combined stage I and II Norwood operation or biventricular repair. RESULTS Between December 2005 and May 2008, 21 neonates were selected for the hybrid procedure, of whom 16 had typical hypoplastic left heart syndrome. The remaining 5 neonates had severe aortic stenosis with borderline left ventricular dimensions or poor left ventricular function at presentation. Four neonates had a virtually intact interatrial septum and required urgent intervention immediately after birth. There were 6 deaths as inpatients or up to 30 days after the procedure and 1 interstage death before the combined stage I and II operation. Thus far, of 12 babies who have undergone the next operation, 9 have had the combined stage I and II operation and 3 have had a biventricular repair. Two of these 12 babies have died after the combined stage I and II operation. CONCLUSION A hybrid approach may be a valuable alternative to the management of high-risk neonates with hypoplastic left heart syndrome and its variants.

Ventricular Aneurysm or Diverticulum? Clinical Differential Diagnosis

Abstract. Intrathoracic ventricular aneurysms and diverticula can be differentiated by several criteria. Contractility is the only reliable parameter: aneurysms expand, whereas diverticula contract during ventricular systole.

Magnetic Resonance–Guided Cardiac Interventions Using Magnetic Resonance–Compatible Devices: A Preclinical Study and First-in-Man Congenital Interventions

Background— Percutaneous cardiac interventions are currently performed under x-ray guidance. Magnetic resonance imaging (MRI) has been used to guide intravascular interventions in the past, but mainly in animals. Translation of MR-guided interventions into humans has been limited by the lack of MR-compatible and safe equipment, such as MR guide wires with mechanical characteristics similar to standard guide wires. The aim of the present study was to evaluate the safety and efficacy of a newly developed MR-safe and compatible passive guide wire in aiding MR-guided cardiac interventions in a swine model and describe the 2 first-in-man solely MR-guided interventions. Methods and Results— In the preclinical trial, the new MR-compatible wire aided the performance of 20 interventions in 5 swine. These consisted of balloon dilation of nondiseased pulmonary and aortic valves, aortic arch, and branch pulmonary arteries. After ethics and regulatory authority approval, the 2 first-in-man MR-guided interventions were performed in a child and an adult, both with elements of valvar pulmonary stenosis. Catheter manipulations were monitored with real-time MRI sequence with interactive modification of imaging plane and slice position. Temporal resolution was 11 to 12 frames/s. Catheterization procedure times were 110 and 80 minutes, respectively. Both patients had successful relief of the valvar stenosis and no procedural complications. Conclusions— The described preclinical study and case reports are encouraging that with the availability of the new MR-compatible and safe guide wire, certain percutaneous cardiac interventions will become feasible to perform solely under MR guidance in the future. A clinical trial is underway in our institution.Background—Percutaneous cardiac interventions are currently performed under x-ray guidance. Magnetic resonance imaging (MRI) has been used to guide intravascular interventions in the past, but mainly in animals. Translation of MR-guided interventions into humans has been limited by the lack of MR-compatible and safe equipment, such as MR guide wires with mechanical characteristics similar to standard guide wires. The aim of the present study was to evaluate the safety and efficacy of a newly developed MR-safe and compatible passive guide wire in aiding MR-guided cardiac interventions in a swine model and describe the 2 first-in-man solely MR-guided interventions. Methods and Results—In the preclinical trial, the new MR-compatible wire aided the performance of 20 interventions in 5 swine. These consisted of balloon dilation of nondiseased pulmonary and aortic valves, aortic arch, and branch pulmonary arteries. After ethics and regulatory authority approval, the 2 first-in-man MR-guided interventions were performed in a child and an adult, both with elements of valvar pulmonary stenosis. Catheter manipulations were monitored with real-time MRI sequence with interactive modification of imaging plane and slice position. Temporal resolution was 11 to 12 frames/s. Catheterization procedure times were 110 and 80 minutes, respectively. Both patients had successful relief of the valvar stenosis and no procedural complications. Conclusions—The described preclinical study and case reports are encouraging that with the availability of the new MR-compatible and safe guide wire, certain percutaneous cardiac interventions will become feasible to perform solely under MR guidance in the future. A clinical trial is underway in our institution.

Analysis of preoperative condition and interstage mortality in Norwood and hybrid procedures for hypoplastic left heart syndrome using the Aristotle scoring system

Objective The ‘hybrid procedure’, consisting of surgical banding of the pulmonary arteries with intraoperative stenting of the arterial duct, was developed as primary palliation in hypoplastic left heart syndrome (HLHS), avoiding the risks of cardiopulmonary bypass. In many centres, it is reserved for low birth weight, premature or unstable neonates; however, its role in such high risk cases of HLHS has yet to be defined. Methods The preoperative condition of all patients with HLHS who underwent either the hybrid or the Norwood procedure for HLHS between 2005–2011 was analysed retrospectively, using a modified comprehensive Aristotle score. We then compared operative, interstage and 1 year mortalities between the groups after Aristotle adjustment via Cox proportional hazards analyses. Results Of 138 patients with HLHS, 27 had hybrid and 111 Norwood procedures. The hybrid group had significantly higher Aristotle scores (mean 4.1 vs 1.8; p<0.001); however, there was no significant difference in mortality at any stage. At 1 year, the overall unadjusted survival among Norwood and hybrid patients was 58.6% and 51.9%, respectively, yielding an Aristotle adjusted hazard ratio for mortality among hybrid patients of 1.09 (95% CI 0.56 to 2.11, p=0.80). Conclusions Applying a hybrid approach to high risk patients with HLHS produces a comparable early and interstage mortality risk to lower risk patients undergoing the Norwood procedure. Prospective studies are needed to establish whether the hybrid procedure is a viable alternative to the Norwood procedure in all HLHS patients in terms of both mortality and long term morbidity.

Cor triatriatum: short review of the literature upon ten new cases.

Cor triatriatum is defined as a membrane within the left atrium, which might lead to restricted pulmonary venous return. Diagnosis is usually achieved by echocardiography, therapy of choice is excision of the membrane. Upon ten new cases, the association with other congenital heart diseases (CHDs), clinical symptoms and the surgical approach are discussed. Eight of ten patients were children, six of them aged < 1 year. Additional CHDs included atrial and ventricular septal defects, partial anomalous pulmonary venous return and complex CHD. Surgery was performed in all cases. Prognosis is related to associated CHD.ZusammenfassungDas Cor triatriatum ist definiert als eine Membran innerhalb des linken Atriums, die zu reduziertem pulmonalvenösem Fluss führen kann. Die Diagnose wird üblicherweise echokardiographisch gestellt. Die Therapie der Wahl bei symptomatischen Patienten ist die chirurgische Exzision der Membran.Anhand zehn neuer Fälle werden die Assoziation mit anderen angeborenen Herzfehlern, die klinischen Symptome und der chirurgische Zugangsweg diskutiert. Acht der zehn Patienten waren Kinder, von diesen wiederum sechs < 1 Jahr alt. Assoziierte Herzfehler lagen bei neun Patienten vor: sieben Vorhofseptumdefekte, ein Ventrikelseptumdefekt, eine valvuläre Pulmonalstenose, eine bikuspide Aortenklappe, ein singulärer Ventrikel, eine partielle Lungenvenenfehlmündung und eine persistierende linke obere Hohlvene. Die Therapie war in allen Fällen chirurgisch, wobei in neun von zehn Fällen bei assoziierten Herzfehlern ein rechtsatrialer Zugang gewählt wurde, während bei isoliertem Cor triatriatum vom linken Atrium aus operiert wurde.

Magnetic Resonance–Guided Cardiac Interventions Using Magnetic Resonance–Compatible DevicesClinical Perspective

Background— Percutaneous cardiac interventions are currently performed under x-ray guidance. Magnetic resonance imaging (MRI) has been used to guide intravascular interventions in the past, but mainly in animals. Translation of MR-guided interventions into humans has been limited by the lack of MR-compatible and safe equipment, such as MR guide wires with mechanical characteristics similar to standard guide wires. The aim of the present study was to evaluate the safety and efficacy of a newly developed MR-safe and compatible passive guide wire in aiding MR-guided cardiac interventions in a swine model and describe the 2 first-in-man solely MR-guided interventions. Methods and Results— In the preclinical trial, the new MR-compatible wire aided the performance of 20 interventions in 5 swine. These consisted of balloon dilation of nondiseased pulmonary and aortic valves, aortic arch, and branch pulmonary arteries. After ethics and regulatory authority approval, the 2 first-in-man MR-guided interventions were performed in a child and an adult, both with elements of valvar pulmonary stenosis. Catheter manipulations were monitored with real-time MRI sequence with interactive modification of imaging plane and slice position. Temporal resolution was 11 to 12 frames/s. Catheterization procedure times were 110 and 80 minutes, respectively. Both patients had successful relief of the valvar stenosis and no procedural complications. Conclusions— The described preclinical study and case reports are encouraging that with the availability of the new MR-compatible and safe guide wire, certain percutaneous cardiac interventions will become feasible to perform solely under MR guidance in the future. A clinical trial is underway in our institution.Background—Percutaneous cardiac interventions are currently performed under x-ray guidance. Magnetic resonance imaging (MRI) has been used to guide intravascular interventions in the past, but mainly in animals. Translation of MR-guided interventions into humans has been limited by the lack of MR-compatible and safe equipment, such as MR guide wires with mechanical characteristics similar to standard guide wires. The aim of the present study was to evaluate the safety and efficacy of a newly developed MR-safe and compatible passive guide wire in aiding MR-guided cardiac interventions in a swine model and describe the 2 first-in-man solely MR-guided interventions. Methods and Results—In the preclinical trial, the new MR-compatible wire aided the performance of 20 interventions in 5 swine. These consisted of balloon dilation of nondiseased pulmonary and aortic valves, aortic arch, and branch pulmonary arteries. After ethics and regulatory authority approval, the 2 first-in-man MR-guided interventions were performed in a child and an adult, both with elements of valvar pulmonary stenosis. Catheter manipulations were monitored with real-time MRI sequence with interactive modification of imaging plane and slice position. Temporal resolution was 11 to 12 frames/s. Catheterization procedure times were 110 and 80 minutes, respectively. Both patients had successful relief of the valvar stenosis and no procedural complications. Conclusions—The described preclinical study and case reports are encouraging that with the availability of the new MR-compatible and safe guide wire, certain percutaneous cardiac interventions will become feasible to perform solely under MR guidance in the future. A clinical trial is underway in our institution.

Results of stent implantation for native and recurrent coarctation of the aorta—follow-up of up to 13 years†

Background: To evaluate the mid and long‐term prognosis after stenting of native or recurrent CoA, we studied the cardiovascular parameters in the follow‐up period up to 13 years. Methods and results: Between 1993 and 2006, 68 patients underwent stent implantation for aortic coarctation (average age 25.5 years, range 5.7–65 years, average weight 65.5 kg, range 32–122 kg). Forty‐six (68%) patients were aged >17 years. Stenting was performed for native coarctation in 41 and for recurrent coarctation in 27 patients, in 23 (34%) patients with a covered stent. Redilation was carried out in 26 (38%) patients. The invasive systolic gradient decreased from mean (±SD) 25 (±15) mm Hg to 5 (±5) mm Hg (P < 0.0005). The descending aorta pressure increased from 80 (±15) mm Hg to 101 (±18) mm Hg. The systolic right arm blood pressure decreased from a mean of 153 (±24) mm Hg to 129 (±18) mm Hg (P < 0.0005). Complications like small dissections were rare. Follow‐up (6 days to 13 years, mean 41 months) was available in 66 patients, in 23 after reintervention at a mean of 71 months, range of 8 months to 10.3 years. Fifty‐one percent remained clinically hypertensive. Conclusions: Stenting of aortic coarctation gives good medium‐term results. Frequent reintervention relate to deliberately under‐dilating stents during the initial procedure. The reintervention rate has reduced since the introduction of covered stents.

Images in cardiovascular medicine. Life-threatening neonatal arrhythmia: successful treatment and confirmation of clinically suspected extreme long QT-syndrome-3.

Here, we demonstrate the electrophysiological findings for a preterm baby who was referred to our center for therapy of persistent complex arrhythmia with heart rate (HR) varying between 60 and 300 bpm. The ECG showed polymorphic ventricular tachycardia (HR 280 bpm), including short runs of torsade de pointes alternating within a few seconds with bradycardia due to third-grade atrioventricular (AV) block (HR 78 bpm, atrial rate 135 bpm), together with broad QRS complexes of 90 ms1/2 (Figure 1 and Data Supplement). During bradycardia, an extreme prolongation of the normalized QT interval (QTc 760 ms1/2) was present (Figure 2). To control tachycardia, treatment with propranolol was given intravenously, resulting in a predominant 2:1 AV block (HR 68 …Here, we demonstrate the electrophysiological findings for a preterm baby who was referred to our center for therapy of persistent complex arrhythmia with heart rate (HR) varying between 60 and 300 bpm. The ECG showed polymorphic ventricular tachycardia (HR 280 bpm), including short runs of torsade de pointes alternating within a few seconds with bradycardia due to third-grade atrioventricular (AV) block (HR 78 bpm, atrial rate 135 bpm), together with broad QRS complexes of 90 ms1/2 (Figure 1 and Data Supplement). During bradycardia, an extreme prolongation of the normalized QT interval (QTc 760 ms1/2) was present (Figure 2). To control tachycardia, treatment with propranolol was given intravenously, resulting in a predominant 2:1 AV block (HR 68 …

Quantification of Temporal, Procedural, and Hardware-Related Factors Influencing Radiation Exposure During Pediatric Cardiac Catheterization

To quantify the impact of relocation to a purpose built pediatric cardiac catheterization laboratory, on patient radiation dose and fluoroscopy time. To provide guide values for radiation exposure during common structural interventions.

A Decade of Staged Norwood Palliation in Hypoplastic Left Heart Syndrome in a Midsized Cardiosurgical Center

Hypoplastic left heart syndrome (HLHS) is a challenge for the pediatric cardiologist and the surgeon. It is generally assumed that the postoperative outcome after surgery for congenital heart disease is influenced by the institutional size. We present the results of 43 patients with true HLHS (situs solitus and atrioventricular and ventriculoarterial concordance) referred for operation between 1992 and 2002 in our center. Two children had atrioseptostomy: one died soon after the operation, and the other one was transplanted successfully but died at the age of 6 months following acute rejection. The remaining 41 underwent Norwood I palliation, 21 stage II palliation, and 10 stage III palliation. Early mortality was 29% after stage I operation, 4.7% after stage II palliation, and 0% after stage III operation. Overall mortality was 39% after stage I, 9.5% after stage II, and 10% after stage III operation. Low birth weight was associated with a higher mortality (p < 0.05). Mortality declined with increasing experience, comparable to the results of very large cardiosurgical centers with many more patients. The quality of surgery and perioperative management in smaller pediatric cardiosurgical centers can reach the level of very large centers.