Safe closure of percutaneous ventricular access site for interventions in structural heart disease.

Percutaneous transapical ventricular access for transcatheter procedures in structural heart disease is associated with an increased risk of bleeding from the access site. There are currently numerous suture and sutureless closure devices that are being investigated to close the transapical access site safely and effectively. Meticulous preprocedural planning with advanced imaging techniques is recommended to lay out the access path and closure of the transapical access site.

Postinfarction ventricular septal rupture: Transcatheter intervention or surgical repair?

Postinfarction ventricular septal rupture is an infrequent but potentially fatal complication of acute myocardial infarction. The 30-day mortality rate with the transcatheter approach when performed in the acute phase (<2 weeks) was 25.3% compared to 50% when surgery is performed in the acute phase (within 3 weeks). There is no correlation between defect size and mortality. New York Heart Association class IV and time to ventricular septal defect closure are risk predictors for transcatheter closure for a 30-day mortality rate of 31.5%.

Transcatheter Intervention for Treatment of Coronary Stenosis After Unroofing of the Anomalous Left Coronary Artery.

Anomalous origin of left coronary artery (LCA) from the right coronary cusp with an intramural course is usually managed with unroofing of the intramural segment. Available literature demonstrates an uneventful course following surgery in most patients. Coronary stenosis following the unroofing procedure treated with percutaneous coronary intervention has not been described in the past. We describe a case where an 11-year-old girl with anomalous origin of the LCA from the right coronary cusp presented with near syncope. Surgical unroofing of the intramural segment was done without any post-operative complications and the patient remained asymptomatic for 9 months. She then presented with chest pain, abnormal troponin levels, and ST-T wave changes on EKG. A CT angiogram done revealed short segment narrowing of the LCA near its origin. Cardiac catheterization with coronary angiography demonstrated short segment narrowing of the LCA just distal to origin. Stenting of the left main coronary artery was done with a drug eluting stent. She underwent the procedure without complications. The patient continued to be asymptomatic 16 months after placement of the stent and there was no residual stenosis seen on a repeat CT angiogram at 3 months after the procedure.

A randomized controlled laboratory study on the long-term effects of methylphenidate on cardiovascular function and structure in rhesus monkeys.

BACKGROUND: Whether long-term methylphenidate (MPH) results in any changes in cardiovascular function or structure can only be properly addressed through a randomized trial using an animal model which permits elevated dosing over an extended period of time. METHODS: We studied 28 male rhesus monkeys (Macaca mulatta) approximately 7 years of age that had been randomly assigned to one of three MPH dosages: vehicle control (0 mg/kg, b.i.d., n = 9), low dose (2.5 mg/kg, b.i.d., n = 9), or high dose (12.5 mg/kg, b.i.d., n = 10). Dosage groups were compared on serum cardiovascular and inflammatory biomarkers, electrocardiograms (ECGs), echocardiograms, myocardial biopsies, and clinical pathology parameters following 5 years of uninterrupted dosing. RESULTS: With the exception of serum myoglobin, there were no statistical differences or apparent dose-response trends in clinical pathology, cardiac inflammatory biomarkers, ECGs, echocardiograms, or myocardial biopsies. The high-dose MPH group had a lower serum myoglobin concentration (979 ng/mL) than either the low-dose group (1882 ng/mL) or the control group (2182 ng/mL). The dose response was inversely proportional to dosage (P = .0006). CONCLUSIONS: Although the findings cannot be directly generalized to humans, chronic MPH exposure is unlikely to be associated with increased cardiovascular risk in healthy children.

Transmyocardial migration of a temporary epicardial pacing wire: a pediatric case report.

Transmyocardial migration of a retained temporary epicardial pacing wire has been rarely reported in adult patients after heart surgery. We present the case of a child in whom a temporary epicardial pacing wire was discovered incidentally in the right ventricular outflow tract one year after surgical repair of congenital heart disease. The pacing wire was subsequently extracted using the snare method during cardiac catheterization. Clinicians caring for patients after congenital heart surgery should be aware of this uncommon though potentially life-threatening complication.

Pediatric cardiomyopathies: causes, epidemiology, clinical course, preventive strategies and therapies.

Pediatric cardiomyopathies, which are rare but serious disorders of the muscles of the heart, affect at least one in every 100,000 children in the USA. Approximately 40% of children with symptomatic cardiomyopathy undergo heart transplantation or die from cardiac complications within 2 years. However, a significant number of children suffering from cardiomyopathy are surviving into adulthood, making it an important chronic illness for both pediatric and adult clinicians to understand. The natural history, risk factors, prevalence and incidence of this pediatric condition were not fully understood before the 1990s. Questions regarding optimal diagnostic, prognostic and treatment methods remain. Children require long-term follow-up into adulthood in order to identify the factors associated with best clinical practice including diagnostic approaches, as well as optimal treatment approaches. In this article, we comprehensively review current research on various presentations of this disease, along with current knowledge about their causes, treatments and clinical outcomes.

Role of transcatheter therapy in the treatment of coarctation of the aorta.

Coarctation of the aorta is one of the most common congenital heart defects. Transcatheter therapy for treatment of coarctation is effective, with low morbidity and mortality rates. The current trend is toward primary stent implantation for treatment, however, the results of balloon angioplasty in children and young adults are equivalent to the results following primary stent placement. Judicious use of stents is recommended in infants and children.

The amplatzer [corrected] septal occluder as a standard for therapy of secundum-type [corrected] atrial septal defect.

Atrial septal defect (ASD) accounts for 5-10% of congenital heart malformations. An uncorrected ASD may lead to congestive heart failure, severe pulmonary hypertension, or paradoxical arterial embolism with stroke. Transthoracic echocardiography is often diagnostic in the pediatric population, but transesophageal echocardiography may be required in adults. Closure of an ASD traditionally has been performed surgically, but the most common type (secundum ASD) can now be closed with a percutaneously deployed device. We briefly describe the types of ASDs and their diagnosis. Results of percutaneous closure in 74 children and adults are then presented.

Effects of controlled antegrade pulmonary blood flow on cardiac function after bidirectional cavopulmonary anastomosis.

BACKGROUND: Bidirectional cavopulmonary anastomosis (BCPA) has been used as an intermediate stage in the treatment of patients with single-ventricle physiology. Leaving additional antegrade pulmonary blood flow has been shown to improve postoperative arterial blood oxygen saturations; however, controversy continues over whether the potential increase in systemic venous pressure is detrimental. We studied the effects of controlled antegrade pulmonary blood flow on cardiac function in patients after BCPA. METHODS: From January 1993 to July 2000, 128 patients underwent BCPA. Mean age at operation was 6.2 +/- 4 months (range 2 to 36 months). In group 1 (n = 72), restricted antegrade pulmonary blood flow was maintained through a native narrowed pulmonary valve or by adjustment of previously placed pulmonary artery band with the goal of maintaining the mean pulmonary artery pressure less than 16 mm Hg. In group 2 (n = 56), BCPA was the only source of pulmonary blood flow. RESULTS: One hospital death (0.8%) occurred. The mean pulmonary artery pressure at the end of the operation was 13 +/- 2 mm Hg in group 1 compared with 12 +/- 2 mm Hg in group 2, a difference that was not significant. Patients in group 1 had higher arterial oxygen saturations (84% +/- 3% compared with 74% +/- 3% in group 2, p < 0.05), and shorter mean hospital stay (9 +/- 3 days compared with 15 +/- 2 days, p < 0.05). Persistent pleural effusion (> 10 days) or late chylothorax occurred in 4 patients from group 1 and 3 from group 2, a difference that was not significant. During a mean follow-up of 36 +/- 10 months no late deaths occurred. The mean oxygen saturation remained higher in group 1, 80% +/- 3% compared with 74% +/- 4% in group 2, and the hematocrit was lower, at 38% +/- 3% compared with 46% +/- 4% (p < 0.05 for both comparisons). Cardiac catheterizations were performed in 68 patients before completion Fontan. Total pulmonary artery (Nakata) index was 263 +/- 34 mm(2)/m(2) in group 1 (n = 40) and 188 +/- 13 mm(2)/m(2) in group 2 (n = 28) (p < 0.05). The mean pulmonary artery pressure and mean ventricular end-diastolic pressure were similar. CONCLUSIONS: Controlled antegrade pulmonary blood flow may have favorable effects on cardiac function for a selected group of patients and does not appear to have adverse effects on subsequent suitability for completion Fontan.

Percutaneous stenting of anastomotic stenoses in tubular interposition grafts used to repair aortic coarctation in adults.

Stenting is the usual treatment for recoarctation following resection with direct end-to-end anastomosis. We describe for the first time stenting to relieve anastomotic stenoses in tubular interposition grafts, which are used to repair approximately 10% of coarctations. Success in these two adults expands further the spectrum of large conduits that may be relieved of stenosis by stenting.

Expression and developmental regulation of the NMDA receptor subunits in the kidney and cardiovascular system.

Antagonists to the N-methyl-D-aspartate (NMDA) receptor bind to various extraneuronal tissues. We therefore assessed the expression of the main NMDA subunit, NR1, in various tissues. We demonstrate that NR1 appears to be most abundant in the rat kidney and heart. NR1 is present in total rat kidney, cortex, and medulla. Of the NR2 subunits, only the NR2C subunit protein is present in the kidney. The abundance of the NR1 subunit protein increases with kidney development. Both NR1 and NR2C are present in opossum kidney, Madin-Darby canine kidney, and LLC-PK(1) cells. Immunohistochemistry studies show that the NR1 subunit is present in the renal proximal tubule. NR1 is abundant in the atrium and ventricle but is also expressed in the aorta and pulmonary artery. The NR2 subunits are not expressed in the heart. NR1 subunit protein expression is constant throughout heart development. Finally, the NR1 subunit protein is expressed in heart cells (H9c2) grown in culture. These studies reveal the presence of the NMDA receptor in the kidney and the cardiovascular system.

Interrupted Aortic Arch.

Interruption of the aortic arch is defined as absence of luminal continuity between the ascending and the descending aorta. This is not an isolated defect; it occurs in conjunction with other cardiac defects such as ventricular septal defect and patent ductus arteriosus. It is a rare malformation. It occurs in about 1% of the patients with congenital heart defects.