Electrocardiographic markers of late sudden death risk in postoperative tetralogy of Fallot children.

Following surgery for tetralogy of Fallot (TOF), children may develop late onset ventricular arrhythmias. Many patients have both depolarization and repolarization abnormalities, including right bundle branch block (RBBB) and QT prolongation. The goal of this study was to improve prospective risk-assessment screening for late onset sudden death.

Fate of mitral regurgitation following repair of atrioventricular septal defect.

The purpose of this study was to evaluate the fate of mitral regurgitation (MR) following repair of atrioventricular septal defects (AVSDs). Echocardiograms of all survivors of isolated AVSD surgery between 1986 and 1996, who had had > or =2 postoperative color Doppler studies (39 patients), were reviewed. On each study, MR severity was graded on a 1+ to 4+ scale, based upon the size of the MR jet.

NMR structural studies of human cystatin C dimers and monomers.

Human cystatin C undergoes dimerization before unfolding. Dimerization leads to a complete loss of its activity as a cysteine proteinase inhibitor. A similar process of dimerization has been observed in cells, and may be related to the amyloid formation seen for the L68Q variant of the protein.

Effect of multiple coil closure of patent ductus arteriosus on blood flow to the left lung as determined by lung perfusion scans.

Lung perfusion scans reveal that multiple-coil closure of the ductus does not interfere with pulmonary blood flow. However, caution is necessary when placing multiple coils in small infants.

Analysis of eicosanoid mediation of the renal functional effects of hyperchloremia.

Depression of GFR and antinatriuresis in response to high chloride has been linked to a cyclooxygenase (COX)-dependent mechanism involving thromboxane A2 (TxA2) and prostaglandin endoperoxide (PGH2), because inhibition of COX prevented the fall in GFR and antinatriuresis produced by hyperchloremia. However, hyperchloremia did not increase, but unexpectedly decreased, renal prostaglandin and TxA2 efflux (Yin et al., 1995).

Balloon Angioplasty for Native Coarctation of the Aorta: Acute and Mid-Term Results.

BACKGROUND: Balloon angioplasty is an accepted treatment for recurrent coarctation of the aorta. Application of this technique to patients with native coarctation is controversial. OBJECTIVE: To report on the immediate and mid-term results of this procedure in patients with native coarctation, including infants <6 months of age.

Comparison Between the Mean dP/dt During Isovolumetric Contraction and Other Echocardiographic Indexes of Ventricular Systolic Function.

Echocardiographic assessments of ventricular function derived from estimates of the mean dP/dt during isovolumetric contraction (mean dP/dt(ic)) were compared with those obtained from measurements of the shortening fraction and the stress-velocity index (SVI). Mean dP/dt(ic) correlated well with the shortening fraction, r = 0.74, P < 0.

Evidence against a cytochrome P450-derived reactive oxygen species as the mediator of the nitric oxide-independent vasodilator effect of bradykinin in the perfused heart of the rat.

The coronary vasodilator effect of bradykinin (BK) in the rat is independent of NO but dependent on activation of phospholipases with involvement of cytochrome P450 mono-oxygenase (P450) and stimulation of Ca++-activated K+ channels, implicating an unidentified hyperpolarizing factor generated via P450 metabolism of arachidonic acid (AA). Because P450 activity also generates free radicals, such as superoxide, which can lead to the formation of hydrogen peroxide and hydroxyl radicals, which are vasoactive, we addressed the contribution of superoxide to the vasodilator effect of BK in the rat heart. Using rat renal microsomes as a source of P450, we verified that P450-dependent metabolism of AA generated superoxide, as detected by chemiluminescence with lucigenin.

Evaluation of Ventricular dP/dt Before and After Open Heart Surgery Using Transesophageal Echocardiography.

The mean dP/dt during isovolumetric contraction (mean dP/dt(ic)) is a new echocardiographic index of ventricular function that has been shown to approximate and closely correlate with invasively measured peak dP/dt. It is amenable to rapid measurement via transesophageal echocardiography (TEE) and is theoretically independent of variations in ventricular anatomy and wall motion. It is therefore well suited for the assessment of ventricular function during surgery.

Survival improvement in anaplastic astrocytoma, combining external radiation with halogenated pyrimidines: final report of RTOG 86-12, Phase I-II study.

Purpose: This study evaluated the toxicity and tumor efficacy of the halopyrimidine IUdR as a chemical modifier of radiation response in patients with malignant glioma. The preliminary results published in 1993 demonstrated no real advantage in the group of patients with glioblastoma. However, a benefit appeared to be evolving in the group of patients with Anaplastic Astrocytoma (AA).

Gradient-enhanced TOCSY experiments with improved sensitivity and solvent suppression.

Gradient-enhanced versions of the homonuclear TOCSY experiment are described, with solvent suppression and sensitivity superior to that of a conventional TOCSY experiment. The pulse sequences are constructed by appending a WATERGATE module to a z-filtered TOCSY experiment. Pulsed-field gradients and appropriately phased selective rf pulses are used to maintain precise control of the water magnetization vector.

Role of phospholipase C and phospholipase A2 in the nitric oxide-independent vasodilator effect of bradykinin in the rat perfused heart.

The cytochrome P450-dependent component of the coronary vasodilator action of bradykinin which requires activation of K+ channels was examined in terms of the contribution of phospholipases in the rat Langendorff heart preparation. This component was isolated by inhibition of nitric oxide synthase with nitroarginine and cyclooxygenase with indomethacin, neither of which affects the coronary vasodilator action of bradykinin. However, nitroarginine elevated coronary perfusion pressure from approximately 40 to 130 mm Hg.

Phase II study of paclitaxel in patients with recurrent malignant glioma.

Purpose: To assess the efficacy and toxicity of paclitaxel administered as a 3-hour infusion to patients with recurrent malignant glioma.

Patients And Methods: Adult patients with recurrent malignant glioma following radiation therapy, who had received no more than one prior chemotherapy regimen and who had a Karnofsky performance status (KPS) > or = 60, were treated with a 3-hour infusion of paclitaxel every 3 weeks. The initial dose was 210 mg/m2; dose escalation to 240 mg/m2 was allowed.

Contribution of calcium-activated potassium channels to the vasodilator effect of bradykinin in the isolated, perfused kidney of the rat.

1. NO- and prostaglandin-independent, endothelium-dependent vasodilator responses to bradykinin are attributed to release of a hyperpolarizing factor. Therefore, the contribution of K+ channels to the renal vasodilator effect of bradykinin was examined in rat perfused kidneys that were preconstricted with phenylephrine and treated with NG-nitro-L-arginine (L-NOARG) and indomethacin to inhibit NO and prostaglandin synthesis.

Aerobic exercise function of patients with persistent coronary artery aneurysms secondary to Kawasaki disease.

Nine patients with persistent coronary artery aneurysms 1.7-14.0 years after an episode of Kawasaki disease underwent progressive bicycle ergometry with expiratory gas analysis.

Possible contribution of platelet cyclooxygenase to the renal vascular action of 5,6-epoxyeicosatrienoic acid.

5,6-Epoxyeicosatrienoic acid (5,6-EET), a cytochrome P450-dependent arachidonate product, is a substrate for cyclooxygenase (COX) and, in some vascular preparations, elicits COX-dependent vasodilation. In the blood perfused rat kidney, 5,6-EET causes COX-dependent renal vasoconstriction, whereas in the rat isolated kidney perfused with a physiological buffer, 5,6-EET produces dose-dependent vasodilation that is unaffected by indomethacin. We examined the possible contribution of platelet COX to the vasoconstrictor action of 5,6-EET.

Stent implantation for relief of pulmonary artery stenosis: immediate and short-term results.

Our objective was to assess the immediate and short-term results of stent implantation to relieve pulmonary artery stenosis (PAS). Thirty-seven patients underwent an attempt at stent implantation at a median age of 7.0 years (range, 0.

Phase II study of prolonged oral therapy with etoposide (VP16) for patients with recurrent malignant glioma.

Because the percentage of dividing cells in malignant gliomas is small, cell cycle specific drugs such as VP16 are most effective if given continuously over prolonged periods. In this study, we chose a dose of 50 mg/day to minimize therapy interruptions for myelosuppression. VP16 was given until the neutrophil count dropped to < 1.

Excision of a pulmonary valve abscess in a 61-year-old woman with single ventricle.

A 61-year-old woman with levo-transposition of the great arteries, double-inlet single left ventricle, and valvar and subvalvar pulmonary stenosis presented with a large pulmonary valve vegetation unresponsive to antibiotic therapy. The diagnostic evaluation and the surgical management are discussed. At operation the pulmonary valve was excised and an abscess cavity was obliterated with a pericardial patch.

The potential role of bacterial superantigens in the pathogenesis of Kawasaki syndrome.

Kawasaki syndrome is an acute multisystem vasculitis of infancy and early childhood associated with high fever, mucocutaneous inflammation, and the development of coronary artery abnormalities. Despite the widely held belief that Kawasaki syndrome is an infectious disease, investigations have failed to identify a causal organism. Previous studies have demonstrated that this illness is associated with marked activation of monocyte/macrophages and the selective expansion of V beta 2-, less so, of V beta 8.

Superantigens in Kawasaki syndrome.

Kawasaki syndrome (KS) is an acute multisystem vasculitis of infancy and early childhood associated with the development of myocarditis and coronary artery abnormalities. Despite the widely held belief that KS is caused by an infectious agent, there remains considerable controversy over its etiology. Recent immunologic and microbiologic studies suggest a potential role for staphylococcal and streptococcal toxins (superantigens) in the pathogenesis of KS.