Left Ventricular Dysfunction after Closure of Large Patent Ductus Arteriosus

Changes in left ventricular dimensions and performance were studied in 43 patients after transcatheter occlusion or surgical ligation of patent ductus arteriosus. The patients were assigned to 2 groups based on their ductal diameter: ≥ 3.1 mm to group A ( n = 27) and ≤ 3 mm to group B ( n = 16). The mean age and weight of the groups were comparable. Before intervention, group A had a significantly larger mean left ventricular end-diastolic diameter than group B, while all patients had normal shortening fraction and ejection fraction. Within 1 month after intervention, left ventricular end-diastolic diameter showed a trend towards regression while shortening fraction and ejection fraction decreased significantly in group A. There were no significant changes in these parameters in group B. Between 1 and 6 months after intervention, left ventricular performance improved in most of the group A patients who were followed up. We conclude that closure of large ductus arteriosus in children leads to significant immediate deterioration of left ventricular performance, which appears to recover within a few months. Echocardiographic study before hospital discharge is recommended in these patients. Serious deterioration of ventricular performance after closure may warrant the use of angiotensin converting enzyme inhibitors.

Stent Implantation to Maintain Patency of a Stenosed Blalock Taussig Shunt

A 14-year-old female with complex congenital heart disease underwent a left-sided classical Blalock Taussig (BT) shunt 15 days after birth. Ten years after the operation her oxygen saturation had decreased significantly. An angiography revealed a severely stenosed BT shunt. Balloon dilation including implantation of a 6 × 13 mm stent was performed successfully. Immediately after intervention, oxygen saturation rose from 55% to 80 84% in room air. Follow-up at a year and a half later showed the classical BT shunt was still patent.

Saudi Guidelines on the Diagnosis and Treatment of Pulmonary Hypertension: Pulmonary hypertension in children

Pulmonary hypertension (PH) is relatively uncommon in children. Pulmonary arterial hypertension (PAH) in pediatric comprises a wide spectrum of diseases, from a transient neonatal condition to a progressive disease associated with morbidity and mortality. Most common PAH in pediatric are idiopathic (IPAH) or PAH associated with congenital heart disease (PAH-CHD), while other associated conditions, such as connective tissue disease (CTD), are less common in pediatrics. Despite better understanding of PH and the availability of new medications during recent decades; the diagnosis, investigation and choice of therapy remain a challenge in children, as evidence-based recommendations depend mainly on adult studies. In this review, we provide a detailed discussion about the distinctive features of PAH in pediatric, mainly emphacysing on classification and diagnostic algorithm.

Saudi guidelines on the diagnosis and treatment of pulmonary hypertension: 2014 updates

The Saudi Association for Pulmonary Hypertension (previously called Saudi Advisory Group for Pulmonary Hypertension) has published the first Saudi Guidelines on Diagnosis and Treatment of Pulmonary Arterial Hypertension back in 2008.[1] That guideline was very detailed and extensive and reviewed most aspects of pulmonary hypertension (PH). One of the disadvantages of such detailed guidelines is the difficulty that some of the readers who just want to get a quick guidance or looking for a specific piece of information might face.

All efforts were made to develop this guideline in an easy-to-read form, making it very handy and helpful to clinicians dealing with PH patients to select the best management strategies for the typical patient suffering from a specific condition. This Guideline was designed to provide recommendations for problems frequently encountered by practicing clinicians involved in management of PH. This publication targets mainly adult and pediatric PH-treating physicians, but can also be used by other physicians interested in PH.

Stent protrusion in palliative congenital heart disease interventions: does it cause any harm?

BACKGROUND

Protrusion of the patent ductus arteriosus (PDA) stent can occur into the lumen of the main pulmonary artery (MPA) branch, the aorta, or both. This protrusion can vary from trivial to major, causing potential obstruction to the vessel lumen, which may cause flow obstruction or risk of thromboses. As far as we know, no one has followed these patients with protruding stents to see whether they do pose a risk of obstruction or thromboses.

METHODS

A retrospective, descriptive, cross-sectional study reviewing charts of all included patients who received stents in the MPA branches with residual protrusion into the pulmonary artery branch lumen (total, 87 patients; 34 patients with protruding stents) was performed to determine whether this protrusion caused any undesired effects on flow or coagulation. The patients were divided into two groups: the protruding stents group (group 1); and the non-protruding stent group that served as a control group (group 2). Each group was then categorized into 3 sections according to the stent position, the PDA, the MPA branches, and the Blalock-Taussig shunt.

RESULTS

The only risk factor that had statistical significance was the number of stents in the PDA site.

CONCLUSION

Protruding stents do not cause an increased risk of thrombosis in patients on aspirin. Mild protrusion is more likely in PDA stents and severe protrusion is more likely in the MPA branch stents. Severe protrusion is more likely when more stents are used in the PDA location. There is no statistical evidence that protrusion can cause lung perfusion defects from the small numbers we have.

Right superior vena cava draining in the left atrium associated with tetralogy of Fallot and pulmonary atresia

We report a case of an anomalous drainage of the right superior vena cava to the left atrium with intact atrial septum associated with Tetralogy of Fallot, pulmonary atresia, and major aortopulmonary collateral arteries.

Alpha(2)-blocker helps to avoid systemic to pulmonary shunt in a prostaglandin dependent infant with critical pulmonary valve stenosis

A 27 days old newborn with critical pulmonary valve stenosis remained prostaglandin (PGE(1)) dependent for 2 weeks after successful balloon valvuloplasty. Only the introduction of Phentolamine in his medication regimen, allowed PGE(1) to be weaned off within days of this therapy. The medication was continued for 4 days and replaced by angiotensin converting enzyme inhibitor (Captopril). Few weeks after the discharge, the patient remained clinically stable with acceptable saturation.

Acute myocardial ischemia following accidental intravenous administration of epinephrine in high concentration

Inadvertent and accidental epinephrine overdose might result in potentially lethal complications. We present a case of acute epinephrine toxicity resulting in acute myocardial ischemia in a young boy with combined variable immunodeficiency syndrome who developed severe allergic reaction to intravenous immunoglobulin, and was subsequently given epinephrine by mistake intravenously rather than subcutaneously. He developed significant ischemic changes in standard 12-lead electrocardiogram, transiently raised cardiac enzymes, reduced left ventricular systolic function, pulmonary edema and pulmonary hemorrhage. It is suggested that special precautionary measures should be taken regarding the dose and the route while administering epinephrine to avoid mishaps.

Transcatheter occlusion of a large left coronary artery to right superior vena cava fistula using the Amplatzer duct occluder device

Transcatheter embolization has become the therapy of choice for most coronary artery fistula. We report a 5.9-kg infant with a coronary artery fistula from the left coronary artery to the right superior vena cava with significant congestive heart failure. The infant underwent successful complete occlusion using the Amplatzer duct occluder.

Survival with hypopituitarism from congenital syphilis

Congenital syphilis continues to occur despite the advances in testing of pregnant women in many countries and the availability of penicillin since 1943. This is a report of a child with multiple systemic manifestations of congenital syphilis. This is one of the few cases of survival with pituitary involvement from congenital syphilis and the first noted case in which diabetes insipidus developed. Institution of routine testing in all countries might have prevented the severe manifestations of syphilis seen in this child.

Pharmacokinetics and pharmacodynamics of milrinone lactate in pediatric patients with septic shock

OBJECTIVES

The objectives of this study were to determine the pharmacokinetics of milrinone lactate in pediatric patients with septic shock and to determine whether a relationship exists between steady-state plasma milrinone concentrations and changes in hemodynamic variables.

STUDY DESIGN

This was a randomized, double-blind, placebo-controlled, interventional study. In study phase 1 patients were randomized and underwent loading and infusion with milrinone lactate (50 microg/kg, then 0.5 microg/kg/min), and invasive hemodynamic values were determined. Steady-state was determined by obtaining plasma samples at 30, 15, and 0 minutes before the end of the milrinone infusion. Study phase 2 started when milrinone was discontinued by the patient care team. Steady-state was reaffirmed and plasma samples were obtained at 0.5, 1, 2, 4, 6, and 8 hours after the end of the infusion.

RESULTS

The average plasma concentration at steady-state (Css avg) and total body clearance for phase 1 were 81.3+/-38.6 ng/ml (mean +/- SD) and 0.0106+/-0.0053 L/kg/min, respectively (n = 9). All but two patients underwent reloading with milrinone. In phase 2 Css avg and total body clearance were 65.8+/-42.1 ng/ml and 0.0110+/-0.0096 L/kg/min, respectively (n = 11). The average time of infusion was 51+/-21 hours. Eight patients were evaluated for phase 2 elimination. The mean elimination rate constant was 0.0091+/-0.0061 min(-1) (n = 8). The median half-life was 1.47 hours (range, 0.62 to 10.85 hours). All patients had creatinine clearances greater than 61 ml/min/1.73 m2. The volume of distribution at steady-state was 1.47+/-1.03 L/kg. No correlation existed between age and the elimination rate constant or the volume of distribution at steady-state. All patients achieved at least a 20% change in cardiac index and systemic vascular resistance index while maintaining a Css avg of 35 to 160 ng/ml. No adverse effects were noted. All patients achieved primary hemodynamic end points (cardiac index and systemic vascular resistance index) during the milrinone infusion.

CONCLUSIONS

Loading doses of 75 microg/kg milrinone lactate and starting infusion rates of 0.75 to 1.0 microg/kg/min for patients with normal renal function should be used; the infusion rate should then be titrated to effect. We recommend that for every increase of 0.25 microg/kg/min, a 25 microg/kg bolus dose be given. Because the median half-life is 1.47 hours, immediate hemodynamic effects may not be seen unless appropriate loading doses and infusion adjustments are made.

Hemodynamic effects of i.v. milrinone lactate in pediatric patients with septic shock. A prospective, double-blinded, randomized, placebo-controlled, interventional study

STUDY OBJECTIVE

To determine the hemodynamic effects of i.v. milrinone lactate in pediatric patients with nonhyperdynamic septic shock. Specifically we tested the hypothesis that i.v. milrinone would increase cardiac index by 20% and decrease systemic vascular resistance index by 20% during a 2-h study period.

DESIGN

Prospective, double-blinded, randomized, placebo-controlled, descriptive, interventional study.

SETTING

Twenty-six-bed pediatric ICU at Children's Medical Center of Dallas and a 10-bed pediatric trauma ICU at Parkland Memorial Hospital.

PATIENTS/PARTICIPANTS

Twelve patients (age range, 9 months to 15 years) with nonhyperdynamic septic shock despite administration of catecholamines (cardiac index [CI] normal [3.5 to 5.5 L/min/m2] or low [< or =3.5 L/min/m2]; systemic vascular resistance index [SVRI] normal [800 to 1,600 dyne.s.cm5/m2] or high [> or =1,600 dyne.s.cm5/m2]; and pulmonary capillary wedge pressure [PCWP] normal [8 to 12 mm Hg] or higher) with clinical signs of poor perfusion were enrolled, randomized, and treated in a blinded fashion with i.v. milrinone and placebo.

INTERVENTIONS

Patients were randomized into two groups. Group A received a loading dose of 50 micrograms/kg i.v. of milrinone followed by a continuous i.v. infusion of 0.5 microgram/kg/min while group B received an equal volume loading dose and continuous infusion of placebo. After 2 h, group A received an equal-volume loading dose followed by a continuous infusion of placebo while the milrinone infusion continued, while group B received a 50 micrograms/kg loading dose of milrinone followed by a continuous infusion of 0.5 microgram/kg/min while the placebo infusion remained. Outcome variable were measured at baseline, 0.5, 1.0, 2.0, 2.5, 3.0, and 4.0 h. Echocardiographic measurements were taken at baseline, hour 2, and hour 4 in all subjects. No changes in other inotropic or mechanical ventilatory support were allowed during the study period.

MEASUREMENTS AND MAIN RESULTS

Milrinone significantly increased CI, stroke volume index (SVI), right and left ventricular stroke work index, and oxygen delivery (Do2) at 0.5, 1.0, and 2.0 h postloading dose (p < 0.05) while significantly decreasing SVRI, pulmonary vascular resistance index, and mean pulmonary arterial pressure at 0.5, 1.0, and 2.0 h postloading dose (p < 0.05). No clinically or statistically significant changes in heart rate, systolic and diastolic BP, mean systemic arterial pressure, or PCWP were observed during milrinone treatment compared to placebo.

CONCLUSIONS

CI, SVI, and Do2 significantly increased while SVRI significantly decreased when compared to placebo after i.v. administration of milrinone to pediatric patients with nonhyperdynamic septic shock. No adverse effects were observed. In a volume-resuscitated pediatric patient with septic shock, when administered in addition to catecholamines, milrinone will improve cardiovascular function.