By F. Jerek. Indiana University Southeast.
These facts should be kept in mind higher-dose single vaginal application regimen buy generic atorvastatin. A when evaluating patients who remain symptom- more common local vaginal irritant is propylene atic after therapy buy 10mg atorvastatin otc. Larger doses of a different azole glycol cheap atorvastatin 10 mg, a chemical preservative used in most vaginal used for a longer period may not increase the treat- creams and suppositories. They are popular choices for fastidious of the medical care team responsible for her care women who either do not relish inserting creams, should be aware that this is an adverse reaction, suppositories, or tablets into the vagina or do not not a normal body response. If such patients need like the increased messiness of the vaginal cream or vaginal antifungal medications in the future, they suppository. Fluconazole has largely replaced the should be guided to use a vaginal antifungal cream original azole, ketoconazole, because a single dose free of propylene glycol or, another option, one of usually suffces. Liver toxicity can be seen with stressed, for the majority of the symptomatic women a prolonged daily dosing regimen, particularly in referred to the vaginitis clinic at Weill Cornell in New patients with underlying liver disease. York with a chronic yeast vulvovaginitis have no yeast For the woman who remains symptomatic after present on vaginal culture. Similar clinical results treatment or the woman with repeated vulvovaginal have been reported by Paul Nyirjesy in his evaluation symptomatology, the treatment decisions are much of 300 patients referred to him with a diagnosis of more complicated. Only 74 were culture The frst step in the care of these patients with positive for yeast. For the patient with negative cultures, women who have received the single-dose therapy the potential sources of problems and therapeutic prescribed for acute C. Fetal abnormalities There are several diagnostic steps to take in the have been documented in pregnant women receiv- patient with recurrent or chronic vulvovaginitis who ing long-term fuconazole treatment. The physician Vulvovaginal Infections 42 should document the relationship to increased Lactobacilli was not effective in preventing Candida symptomatology with sexual activities and deter- vulvovaginitis after antibiotic treatment. Although circum- not surprising, for vaginal Lactobacilli are often cision is done in nearly all newborn males in the present in women with a Candida vaginitis. Some United States, there are many immigrant males from patients cling to a restrictive dietary regimen that around the world who have never been circumcised. This can be a placebo For example, circumcision is not routinely per- effect, but in our opinion, it is more likely the result formed in the United Kingdom. Candida vulvovaginitis, it is wise to have someone There is another important preliminary diagnos- examine and culture the often asymptomatic male. Some women are allergic of symptoms and the use of preventive antifungal to the latex in condoms or to the nonoxynol-9 that therapy, either oral or local, in women with repeated coats most commercial condoms, and this also can documented Candida infections. These are clinical In those patients with culture-documented situations where modifcations in sexual practices chronic or recurrent C. There is also evidence that oral sexual of therapy to protracted maintenance treatment contact can be responsible for some cases of recur- schemes. It works for many patients, and be explored in the history taking followed by an oral there is evidence that these women have increased cavity examination and culture of the sexual partner, levels of C. There is There should be caution and careful consideration a wide range of treatment regimens available that given to the therapeutic regimen for women with a should be employed for at least 6 months. Although patient prefers a local vaginal treatment, the weekly treatment failures are not usually due to C. Physicians Ketoconazole 100 mg given daily for 6 months was should not disregard the long half-life of fucon- effective,35 as was itraconazole 50–100 mg daily. After treatment stopped, to not adding any therapeutic advantage, this dos- this beneft was not maintained, for 6 months later, age regimen increases the possibility of an adverse only 42. The Spartan-like of either vaginal or oral azoles, another study found restrictive low-carbohydrate diet combined with that using 600 mg of boric acid during the frst the concomitant use of oral nystatin popularized 5 days of the menstrual cycle was quite effective. It presents microscopi- on long-term azole prophylaxis also have a higher- cally as a feld loaded with spores. The response to both oral and vaginal azoles, while vagi- care of these women requires culture and the iden- nal boric acid 600 mg for 14 days has been highly tifcation of non-albicans species so that appropriate effective. It is vitally important to Some physician intervention may not be appro- identify and treat these patients, for symptomatic priate for every patient. Another popular thera- diagnosis, it is important that the laboratory can peutic intervention in women with symptoms of go beyond the characterization of these isolates as chronic vulvovaginitis is the physician-applied local non-albicans and identify the species recovered. There physicians should be most concerned about the iden- are potential problems with this approach: it is often tifcation of C. In these patients, topical boric acid diagnosis and treat the patient at the frst clinical resulted in a cure in the majority of cases. There is no dishonor in holding off therapy acid fails, prolonged treatment (6 weeks) with topi- when in doubt, until all culture results are available. A much utilizing treatment interventions that will not help more common non-albicans isolate is C. The products because of its potential toxicity, especially effect of vaginal candidiasis on the shedding for children. Three grams taken orally may be fatal of human immunodefciency virus in cer- to a child. Am J Obstet Gynecol the vagina, but instances of neurotoxicity (nau- 2005;192:774–779. N Engl J sea, headaches, disorientation) have been noted in Med 2007;369:1961–1971. Vaginal colonization by Candida in with compounding capabilities, for there are no asymptomatic women with and without a tested commercial products available. Cornell clinic, a vaginal cream with 6% amphotericin Obstet Gynecol 2000;95:413–416. The mannan in sera of patients with recurrent cross-talk between opportunistic fungi and vulvovaginal candidiasis. Vaginal microbiology of rophage defect in women with recurrent women with acute recurrent vulvovaginal can- Candida vaginitis and its reversal in vitro by didiasis. Recurrent Prevalence and risk factors for vaginal candida vaginitis as a result of sexual transmis- colonization in women with type 1 and type 2 sion of IgE antibodies. Diffculties in the diagnosis of Candida vagi- Genotyping and drug resistance profle of nitis. Br J Obstet Gynaecol of Candida albicans infection and clotrima- 2015;122:785–794. Cytokine and chemokines heat shock protein gene transcription production by human oral and vaginal epi- and inhibits interferon-gamma messen- thelial cells in response to Candida albicans. Oral gen binding molecules and immuno- sex and recurrent vulvo-vaginal candidiasis. Saccharomyces cerevisiae vaginitis: of maintenance therapy with topical boric acid Transmission from yeast used in baking.
This is not adequate for the fully heparinized patient undergoing cardiac surgery order on line atorvastatin. Numerous unsuccessful attempts were made beginning in the 1960s to achieve tem- porary porosity control with biologic sealants other than the patient’s own fbrin clot buy cheap atorvastatin 40mg online. In very low acceptable blood loss in the heparinized patient requires 2 porosity grafts discount atorvastatin generic, the pseudointima is poorly anchored to the Dacron a porosity of less than 50 ml/cm per minute, even these and tends to dissect. It has also been In the 1980s, the Hemashield process (Meadox Medical) for highly successful as a long-term implant for the extracardiac presealing both knitted and woven Dacron was introduced conduit Fontan procedure in larger sizes such as 16–22 mm. With both methods of presealing, it is important to ation where the external surface will be exposed to blood, remember that stronger woven Dacron is recommended for for example, for the intra/extracardiac conduit modifcation replacement of the thoracic aorta in adults while knitted of the Fontan procedure. However, Impra is identical on its Dacron has better healing characteristics and is preferable for internal and external surface and therefore may be preferable smaller diameter grafts (e. Dacron conduits should rarely be used Endothelial Lining of Synthetic Prostheses in a diameter of less than 12 mm and ideally no less than To improve the long-term patency of small caliber conduits, 20–22 mm because of its accumulation of pseudointima. Endothelial cells the polymer is arranged as a lattice of nodes interconnected can be mechanically or enzymatically debrided from a suit- by flaments. It excites much less of an infammatory, fbrous able dispensable autologous blood vessel. However, early clinical implants used suspended in the patient’s blood, which is used to preclot the for aortic or iliac artery replacement had a tendency toward prosthesis. Attention is currently being directed at the role of the basement membrane in facilitating normal endothelial cell function. The future may lie with tissue engineering tech- niques to develop the entire vessel architecture using autolo- gous cells seeded on to bioresorbable scaffolds. The fgure illustrates unim- description of the use of an autologous pericardial tube in planted Hemashield-treated Dacron showing the sealant material. The spe- Ross and Somerville introduced the concept of a valved, aor- cifc antibiotics employed can also infuence the long-term tic allograft conduit in Britain in 1966 (see Fig. Studies by Armiger and associ- Gross’s allograft conduits for coarctation, Ross included the ates in the 1980s suggested that a combination of cefoxitin, aortic valve with the aortic root and ascending aorta, thus lincomycin, polymyxin B, vancomycin, and amphoteri- recreating the valved right ventricular outfow tract. Changes in the antibiotic formulation aortic valve replacement, at least two important changes to may have been responsible at least in part for cases of seri- Ross’s original method were made. First, instead of a weak ous sepsis and viral transmission that have occurred with antibiotic solution to ‘sterilize’ the allografts, high-power implantation of allograft tissue other than valves and con- irradiation was employed. Fortunately, serious sepsis has not been observed with anced salt solution, with or without a tissue culture medium cardiac allograft tissue. These techniques, particularly in combination, led to the death of cells and severe Cellular Viability and Long-Term Allograft Performance damage to the collagen within the valve leafets. Although A long-standing controversy centered on the importance of Ross had observed calcifcation in the wall of this conduit, 37,38 continuing viability of donor cells in the maintenance of valve leafet calcifcation had been extremely rare. The point of view espoused by Barratt- trast, stenosis rapidly developed in the valve of the irradiated, Boyes for many years was that the allograft is primarily freeze-dried allograft, and therefore, allografts fell into gen- a collagenous skeleton and that donor cellular viability eral disrepute in the United States until they were rediscov- 39 is unimportant. Appropriate preparation is also important to encourage The organization of regional organ and tissue banks has both ongrowth and ingrowth of recipient cells onto the facilitated the collection of allografts. The collection was undertaken in the sterile The usual mechanism of failure of allografts when placed setting of an operating room. Following a rapid increase in as a valve in the aortic position is rupture of the leafets in demand for a wide range of allograft sizes by the late 1980s, the hinge area, resulting in valvar regurgitation. In the case homograft collection expanded to include cadavers, as has of aortic allograft conduits, the conduit wall almost always been the practice in the United Kingdom, New Zealand, and becomes heavily calcifed, so it is unlikely that viability of other countries since the 1960s. In the early 1990s, the Food cells could infuence the durability of conduit function. This presents a major logistic problem, particu- as elastin tends to be the nidus for calcifcation. At least larly in the management of smaller children, where the num- three laboratory studies have suggested that pulmonary ber of appropriate-size donors is limited. Major advances in allografts harvested from immature animals and implanted cryopreservation technology currently allow the preservation into growing animals can increase in size with time. Choosing the Right Biomaterial 255 An alternative to the collagenous skeleton theory was the implant size. In an anecdotal case on the clinical experience of vascular surgeons during the in which a valve was retrieved 10 years after implanta- 1950s, it seems likely that with more widespread applica- tion, they were able to demonstrate by chromosome stud- tion of this biologic material, there will be occasional very ies that donor cells were viable. Others have argued that late (decades) failure by allograft rupture or the formation this does not confrm a functional role for any remaining of pseudoaneurysms or conduit to bronchus fstulas. When durability of homografts, the importance of cellular viabil- applied in a situation where it will be exposed to pressure ity has been questioned. Clinical implants are presently 1989 and have been seen regularly since, sometimes follow- being undertaken, but reports are conficting regarding ing balloon dilation. Nevertheless, it would seem prudent to limit in the mid-1980s, most allografts used clinically were non- the use of pulmonary allografts to sites where the predicted viable, so immune reactions to cellular elements were irrel- intra-allograft pressure will be substantially subsystemic. After the introduction of cryopreserved ‘viable’ allografts, attention was directed Femoral Vein Homograft Conduits at the potential role of immune mechanisms in damag- Collection of an adequate number of aortic and pulmonary ing allograft durability. In a series of elegant experiments, 51 valved allografts from young donors with valve diameters in Yankah and coworkers demonstrated that implantation of a the range of 12–18 mm is diffcult in the United States and in viable aortic allograft in the abdominal aorta of inbred spe- many countries virtually impossible because of cultural tra- cies of rats resulted in accelerated rejection of skin grafts ditions. An excellent alternative that should be readily avail- from the same donor species. This has led some centers to able in any country is the femoral vein homograft from adult use short-term immunosuppression in patients after allograft donors which avoids the need for removal of the heart and valve insertion. However, this does not seem to be justifed requires a cosmetically acceptable incision. Cryopreserved until a more formal clinical study has conclusively demon- adult femoral vein is available in the United States from strated signifcant benefts of such an approach. It is Mode of Failure of Allograft Conduits ideal for application in the Norwood operation as it is thin but strong and hemostatic. Longitudinal right ventricle to pulmonary artery conduit for neonates and young infants. Aggressive calcifcation can protrude into the lumen and the valve leafets Bioprosthetic Conduits may become rigid and stenotic and even calcifed. Porcine Valved Dacron Conduits Experience with the Ross procedure, in which large Very low porosity woven Dacron conduits containing a allograft conduits are placed in the orthotopic position and glutaraldehyde-treated pig valve were introduced in the there is little or no risk of compression, has revealed a dis- 1970s. There have been conficting reports regard- ing the long-term performance of these conduits, including several reports that have described early severe distal anasto- motic fbrosis and stenosis. These conduits failed rapidly in children because of a combina- risk of accelerated calcifcation when used in children less than tion of pseudointima formation on the low porosity Dacron, as well 18–20 years of age. Reports have suggested satisfactory per- as calcifcation of the gluataraldehyde-treated xenograft valve.
Costs can increase markedly in the presence of complications buy atorvastatin 40mg with amex, and longer length of stay (40) cheap atorvastatin 40mg mastercard. Whereas such research throughput is increasing quality 5 mg atorvastatin, generating comprehensive estimates of cost continue to be extremely challenging. Not only do costs vary by institution (41), but in general depend on context, perspective, and definitions. The local context is critical: Clinical factors (survival, rate of complications) and organizational systems (health delivery systems, payor structure) vary P. Cost estimates also depend on perspective: depending on whose view is taken—the patient (client), the health delivery system, or society as a whole—estimates can vary considerably. Finally, definitions, and in particular inclusion criteria, are crucial: inpatient medical costs, for which data are comparatively easy to obtain, are an important component of cost, but not the only one; other direct and indirect costs, including loss of productivity, can be considerable and may exceed the inpatient costs, but are more difficult to estimate. A further challenge is estimating costs over the lifespan, which would provide a realistic assessment of the benefits of prevention. Short-Term Assessment: Cross-Sectional Costs Cross-sectional costs are more readily available and can provide an immediate if rough estimate of the potential impact of prevention on cost. Over one-third of this figure, 511 million dollars, was due to a small subset of severe heart defects—conotruncal defects, single ventricle, hypoplastic left heart syndrome, Ebstein anomaly, and atrioventricular septal defects. In an attempt to incorporate outpatient data also, researchers used a different dataset limited to a privately insured population (33), and estimated medical costs (inpatient and outpatient) associated with major heart defects to be approximately $100,000 among children up to 3 years of age. For adults, few data are available, and these are likely underestimates due to the uncertainties of coding in administrative datasets (46). Long-Term View: Lifetime Costs Compared to cross-sectional costs in a given age range, lifetime estimates can provide a more accurate view of the benefits of prevention—for example, preventing a diabetes-associated heart defect saves costs over a lifetime of that baby. Because of this longitudinal component, estimating lifetime costs is understandably challenging, and requires modeling, data, and assumptions. An older study, but still one of the more comprehensive, estimated lifetime costs of 1. Even from this brief review, it is evident that comprehensive costs estimates are remarkably scarce, surprisingly so in an environment of increasing healthcare expenditures and limited resources. With few exceptions, available estimates are also far from timely, a major limitation for such a dynamic issue as cost. These gaps reflect in part the limitations and accessibility of current data sources, often fragmented and opaque. Greater transparency and integration will be required for reliable cost information. Top Left: Estimated inpatient cost for 1 year due to congenital heart defects (overall and for severe types) in 2004, United States. Top Right: Inpatient and outpatient costs (Mediscan data) for children under 3 years of age, by type of congenital heart defect, United States. Bottom Left: Estimated lifetime costs (direct and indirect, in 1992 dollars) per case, United States. Congenital Heart Disease: Molecular Genetics, Principles of Diagnosis and Treatment: S. Evaluating and tracking outcomes locally can help identify population-specific problems and disparities and their local determinants. Nearly everywhere, congenital heart defects are significant contributors to adverse health outcomes (2). Mortality Internationally, congenital heart defects are the leading cause of infant deaths due to congenital anomalies— accounting for approximately 1 in 3 such infant deaths (47,48). The contribution to neonatal deaths is also significant—in the United States (49) and in several European countries (13) congenital heart defects account for an estimated 1 in 4 neonatal deaths to birth defects. In developed countries, congenital heart defects are estimated to account for approximately 1 in 10 infant deaths from any cause (47,48). In infants and young children, a disproportionate fraction of deaths is due to relatively few types of heart defects, particularly hypoplastic left heart syndrome, conotruncal defects, and atrioventricular septal defects (50). This finding further underscores the importance of monitoring, preventing, and treating the subset of severe congenital heart defects. Notably, excess mortality does not end in early childhood, but extends for many decades in adult life, as documented in a longitudinal population-based study in Denmark (51) as well as in a study of death certificates in the United States (52). Developmental Disabilities Adverse neurodevelopmental outcomes are an increasingly appreciated component of the burden of disease for people with congenital heart defects. In one survey, clinicians and parents of children with congenital heart defects rated neurologic disability a greater concern than cardiac disability (53). With longer life expectancy, these outcomes are increasingly relevant (54,55,56,57,58,59,60,61,62,63,64). First, neurodevelopmental challenges are common when additional malformations or a genetic syndrome is present—even when a genetic condition is suspected but not specifically identified (65). Brain anomalies, such as neuronal migration defects and Chiari I malformation can be found in children with apparently isolated congenital heart defects (66). Fetal brain changes have been reported in some children with congenital heart defects (61,67), on the basis of volumetric analysis of the fetal brain and on magnetic resonance spectroscopy (67). After birth, suggested risk factors for adverse neurodevelopmental outcomes include altered hemodynamics, cyanosis, or the stress related to complications of surgery, low birth weight, or preterm birth (54,62,65,68,69,70,71,72,73). In general, intellectual disability is likely rare in the absence of genetic conditions and severe postnatal complications. However, whereas overall intelligence is typically within the normal range in older children and adolescents, other subtler findings—deficits in executive function, attention deficit and hyperactivity disorders, anxiety, and depression—could be more common than previously thought. Several investigators have voiced methodologic concerns in current studies— including the general moderate quality of the studies (106) and the scarcity of longitudinal studies (with most studies being cross-sectional). In the Norwegian Mother and Child Cohort Study (MoBa), investigators linked the cohort of 44,000 children to the Norwegian nationwide heart defect registry and identified 175 children of 3 years of age with congenital heart defects, 60 of whom had severe defects. Compared to controls, children with severe heart defects had more than a three-fold risk for communication and gross motor impairments, and a two-fold increased risk for any developmental impairment. Children with mild and moderate heart defects had a two-fold higher risk for gross motor impairment but did not otherwise differ from controls. Of note, impairments were more frequent among children already noted to have developmental delays and a smaller head size at birth (75). The investigators recommended early assessment for motor and communication support provided in children with congenital heart defects, particularly severe types, with the goal of improving long-term outcomes. Notably, these same children did not have a higher risk of internalizing or externalizing emotional problems at 36 months of age compared to controls (76), possibly because they were past the main period of morbidity and hospitalizations. These studies are notable for their systematic, longitudinal, and prospective design, and will hopefully continue to generate important outcome data on older children and adults, with fewer biases and greater generalizability than clinic-based case series on which most current data derives. In summary, some children with congenital heart defects appear to be at risk for adverse development and psychological outcomes, although firm data on frequency, magnitude of risk, and predictors are still scarce. Also, incorporating these outcomes into the “cost” of congenital heart defects would provide a more realistic evaluation of the potential benefits of primary prevention, and a further incentive for research and preventive interventions. Quality of Life Together with neurodevelopment, health-related quality of life is increasingly and appropriately viewed as a significant outcome in pediatric cardiology (see Chapter 77) (58,77,78).
Somatic chromosome abnormalities in the lungs of patients with pulmonary arterial hypertension order cheapest atorvastatin and atorvastatin. Narrative review: the enigma of pulmonary arterial hypertension: new insights from genetic studies purchase atorvastatin with a mastercard. Transforming growth factor-beta receptor mutations and pulmonary arterial hypertension in childhood generic 40 mg atorvastatin. Serotonin transporter overexpression is responsible for pulmonary artery smooth muscle hyperplasia in primary pulmonary hypertension. Serotonin transporter polymorphisms in familial and idiopathic pulmonary arterial hypertension. Prevalence and outcome in systemic sclerosis associated pulmonary arterial hypertension: application of a registry approach. Continuous intravenous epoprostenol for pulmonary hypertension due to the scleroderma spectrum of disease. Epoprostenol for treatment of pulmonary hypertension in patients with systemic lupus erythematosus. Connective tissue disease presenting with signs and symptoms of pulmonary hypertension in children. Preterm infants with congenital heart disease and bronchopulmonary dysplasia: postoperative course and outcome after cardiac surgery. Pulmonary arterial hypertension in adults born with a heart septal defect: the Euro Heart Survey on adult congenital heart disease. Isolated atrial septal defect with pulmonary vascular obstructive disease–long-term follow-up and prediction of outcome after surgical correction. Incidence of secondary pulmonary hypertension in adults with atrial septal or sinus venosus defects. Preoperative pulmonary hemodynamics and assessment of operability: is there a pulmonary vascular resistance that precludes cardiac operation? Comparison of hyperventilation and inhaled nitric oxide for pulmonary hypertension after repair of congenital heart disease. Assessment of operability of congenital cardiac shunts with increased pulmonary vascular resistance. Clinical applications of inhaled nitric oxide in children with pulmonary hypertension. Use of inhaled nitric oxide and acetylcholine in the evaluation of pulmonary hypertension and endothelial function after cardiopulmonary bypass. Pulmonary vascular bed in children with complete atrioventricular septal defect: relation between structural and hemodynamic abnormalities. Pulmonary arterial hypertension and congenital heart disease: targeted therapies and operability. Pulmonary vascular disease with congenital heart lesions: pathologic features and causes. Measurement, interpretation and use of haemodynamic parameters in pulmonary hypertension associated with congenital cardiac disease. Late results after correction of ventricular septal defect with severe pulmonary hypertension. Measured versus estimated oxygen consumption in ventilated patients with congenital heart disease: the validity of predictive equations. Validity of the LaFarge equation for estimation of oxygen consumption in ventilated children with congenital heart disease younger than 3 years–a revisit. The pulmonary vascular response to oxygen and its influence on operative results in children with ventricular septal defect. Assessment and follow-up of patients with ventricular septal defect and elevated pulmonary vascular resistance. Late results (30 to 35 years) after operative closure of isolated ventricular septal defect from 1954 to 1960. Inhaled nitric oxide to test the vasodilator capacity of the pulmonary vascular bed in children with long-standing pulmonary hypertension and congenital heart disease. Combined effects of nitric oxide and oxygen during acute pulmonary vasodilator testing. Long-term outcome of patients operated for large ventricular septal defects with increased pulmonary vascular resistance. Repair of congenital heart disease with associated pulmonary hypertension in children: what are the minimal investigative procedures? Assessment of operability of patients with pulmonary arterial hypertension associated with congenital heart disease. Correlations of lung morphology, pulmonary vascular resistance, and outcome in children with congenital heart disease. Circulating endothelial cells in refractory pulmonary hypertension in children: markers of treatment efficacy and clinical worsening. Circulating endothelial cells: a new candidate biomarker of irreversible pulmonary hypertension secondary to congenital heart disease. Evaluating operability in adults with congenital heart disease and the role of pretreatment with targeted pulmonary arterial hypertension therapy. Current era survival of patients with pulmonary arterial hypertension associated with congenital heart disease: a comparison between clinical subgroups. Eisenmenger syndrome a clinical perspective in a new therapeutic era of pulmonary arterial hypertension. Comparison of the hemodynamics and survival of adults with severe primary pulmonary hypertension or Eisenmenger syndrome. Determinants of survival and length of survival in adults with Eisenmenger syndrome. Eisenmenger syndrome in adults: ventricular septal defect, truncus arteriosus, univentricular heart. B-type natriuretic peptide concentrations in contemporary Eisenmenger syndrome patients: predictive value and response to disease targeting therapy. Replacement therapy for iron deficiency improves exercise capacity and quality of life in patients with cyanotic congenital heart disease and/or the Eisenmenger syndrome. Phosphodiesterase-5 inhibitor in Eisenmenger syndrome: a preliminary observational study. Bosentan therapy in patients with Eisenmenger syndrome: a multicenter, double-blind, randomized, placebo-controlled study. Improved survival among patients with Eisenmenger syndrome receiving advanced therapy for pulmonary arterial hypertension. Long-term effect of bosentan in adults versus children with pulmonary arterial hypertension associated with systemic-to-pulmonary shunt: does the beneficial effect persist? Pulmonary arterial hypertension in adults with congenital heart disease: distinct differences from other causes of pulmonary arterial hypertension and management implications. What limits cardiac performance during exercise in normal subjects and in healthy Fontan patients? Clinical outcomes and improved survival in patients with protein-losing enteropathy after the Fontan operation.
However atorvastatin 5 mg, indices based on the measurement of a single-tissue velocity point purchase genuine atorvastatin line, which is often variable and difficult to identify buy generic atorvastatin 20 mg, tend to have poor intra- and interobserver reliability (154). The relative delay between the two segments of interest (the shift in curves) can then be calculated using cross-correlation computation (166). This computation is not yet routinely available on common commercial ultrasound analysis platforms. Major disadvantages include difficulties in identifying peak systolic motion when multiple peaks are present or when a clear peak is not visible. Moreover, motion of the interrogated segment may be passive due to translation of the entire heart or due to tethering of a noncontractile segment to adjacent segments. The importance of tethering in children, who generally do not have discrete regions of infarcted myocardium except in very specific circumstances, is unknown. Aortic valve opening and closing are marked by the green lines to delineate ventricular ejection. In panel A 12 tissue Doppler curves are obtained from the basal and midregions from apical 4 (top), 2 (middle), and 3 (bottom) chamber views. The standard deviation of the time-to-peak velocity during ejection is measured as the dyssynchrony index. In this normal example, tissue velocities reach their peak nearly simultaneously so that the standard deviation of time-to-peak velocity curves is low. In contrast, panel B shows curves from a patient with dilated cardiomyopathy where different segments reach peak velocity at different times. One method measures the delay between time-to-peak radial strain between the septum and posterior wall (similar to the M-mode technique) at midventricular level with a 130 ms cutoff quoted in the adult P. Other authors have used the delay between time-to-peak longitudinal strain in the septum and lateral wall. By measuring active contraction, strain imaging overcomes the problem of passive translational motion and tethering. Other disadvantages include: lower frame rate than tissue Doppler (for speckle tracking), lack of segment measurement standardization, size of region of interest (171), and relatively poor reproducibility. Despite the theoretical benefits of deformation imaging, our practical experience has been that it is difficult to obtain reliable strain curves for dyssynchrony measurements in a substantial proportion of children with ventricular dysfunction. Note that peak systolic strain occurs nearly simultaneously in the six measured segments. The standard deviation of time to minimal volume between 12 and 16 subvolumes is then used as a dyssynchrony index (Fig. To account for different heart rates, the dyssynchrony index can be expressed as a percentage of the cardiac cycle length. Disadvantages of 3-D echo are the low frame rates and the indirect assessment of wall motion through assessment of volume change. Assessment of Mechanical Dyssynchrony in Children Dyssynchrony has been shown to be important in children and adolescents in a number of acquired and congenital conditions. Most studies have largely been restricted to investigating the prevalence of dyssynchrony in various conditions and investigating its impact on cardiac function, exercise capacity, and clinical outcomes. In children with dilated cardiomyopathy, and in normal controls, the degree of radial deformation (which is related to contractility) was found to be related to the time it took to develop peak deformation, thereby providing a direct link between timing of contraction and regional function (180). Diastolic dyssynchrony has also been found to be prevalent in this population and is possibly linked to increased risk for death or transplant (184). Dyssynchrony, demonstrated by echo, is also important in children with congenital heart disease. Likewise an increased interventricular delay has been linked with decreased exercise capacity and increased risk for ventricular arrhythmias during exercise (161). Whether this dyssynchrony constitutes a marker for later development of ventricular dysfunction in this population, is unknown. Indeed, increased mechanical dyssynchrony by tissue Doppler and strain imaging may be associated with decreased cardiac output after congenital heart disease surgery, and this may respond to biventricular pacing. The change in each subvolume over the cardiac cycle is represented in the curves at the bottom of the figure. Coronary Artery Physiology Coronary artery physiology and pathology play an important role in congenital conditions, and assessment of coronary artery physiology is gaining an increasingly important role for the pediatric and congenital echocardiographer. In children, coronary artery abnormalities are predominantly related to (a) an abnormal origin or course (e. The specific etiology in question will influence the type and extent of imaging performed. Two-dimensional and color flow echocardiography are useful for imaging coronary artery origins, course, aneurysms, and dilatation, but are less useful for detecting coronary artery stenosis, aside from perhaps coronary ostial stenosis. Coronary echocardiography or ultrasound can be divided into the following broad categories: 1. Assessment of regional myocardial function at rest and during stress that may indicate perfusion abnormalities in specific myocardial territories 3. Vascular imaging to detect early atherosclerosis In this section, we refer to general imaging of coronary artery physiology. Coronary physiology can be assessed by studying peripheral arterial structure and function or by direct interrogation of the coronary arteries themselves. The peripheral arteries serve as surrogate windows for the study of coronary artery physiology. Peripheral arterial endothelial function is assessed by brachial artery flow-mediated dilation. This technique involves inflating a sphygmomanometer cuff placed on the forearm or upper arm to a pressure of 100 to 150 mm Hg above the systolic pressure for 4 to 5 minutes. The brachial artery diameter immediately after cuff deflation is compared with the baseline diameter before inflation. The technique produces very subtle changes and must be performed in a highly controlled environment free of extraneous influences. Both carotid intima-medial thickness and brachial artery flow-mediated dilation have been used successfully to show impairment of vascular function, and therefore, presumably coronary arterial function in children with insulin-dependent diabetes mellitus (198,199). Vascular function can also be assessed by applanation tonometry, a nonultrasound technique that necessitates noninvasive capture of a large artery waveform using high-fidelity transducers and from which cardiovascular risk can be assessed (200). Direct assessment of the coronary arteries is still limited and a coronary abnormality should be considered when other signs of myocardial ischemia or infarction are present, such as global or regional ventricular dysfunction, ventricular and atrial enlargement, the presence of mitral regurgitation, echogenic papillary muscles or myocardium, and flow reversal in the left anterior descending artery by color flow Doppler in anomalous origin of the left coronary artery from the pulmonary artery. Direct functional assessment of the coronary arteries largely rests on Doppler assessment of coronary flow although it is not routinely performed in most pediatric clinical institutions. Nonetheless, Doppler flow velocities have been found to correlate well with invasive measurements by Doppler guide wire in adults and in pediatric studies, albeit in a small number of subjects (201,202,203). Normal values for Doppler flow velocities at rest in the left coronary artery have been published in a cohort of over 300 children (204), and have been studied in the branch coronary arteries (205). Velocities, which ranged up to 60 cm/s in young children, decreased with age and increased with heart rate. Coronary flow reserve reflects the increase in coronary flow in response to stimuli such as pharmacologic agents (e. It is calculated as the ratio of the peak (or mean) diastolic velocity after hyperemic stimulation to the baseline peak (or mean) diastolic velocity and reflects the resistance of the coronary bed, its ability to maintain constant flow when myocardial perfusion pressure changes (autoregulation), and the ability to augment blood flow in response to stress (206). Coronary flow reserve is affected not only by stenosis or compression of the proximal coronary arteries, such as in Kawasaki disease (203,207) or hypertrophic cardiomyopathy (208), but also by abnormalities in the distal coronary microvasculature such as in dilated cardiomyopathy, where decreased coronary flow reserve by Doppler echo has been linked to worse outcome (209,210).