Congenital heart disease in the adult: what should the adult cardiologist know?

There is an increasing population of adults with congenital heart disease (CHD) due to successful pediatric medical and surgical intervention, and commensurate with this increase is a rise in heart failure, hospital admissions, and hospital costs among adult CHD patients. This group of patients requires careful long-term evaluation and follow-up of the residua and sequelae of their cardiac anomalies that arise in adulthood to prevent late complications. This article addresses congenital heart defects that are encountered in a general adult cardiology practice and reviews clinical, anatomic, and imaging features of each lesion, fundamental management issues, indications for interventions (and often re-interventions), issues related to endocarditis prophylaxis, pregnancy, and appropriateness of referral to a dedicated adult CHD program for long-term care.

Ultrasound findings in Plasmodium falciparum malaria: a pilot study.

OBJECTIVE: To investigate whether hand-carried ultrasound technology may be valuable in the assessment of children with acute malaria. Every year, approximately 800,000 children under the age of 5 yrs die of complications of Plasmodium falciparum malaria infection. The advent of hand-carried ultrasound technology has made diagnostic ultrasonography possible in underresourced settings. DESIGN: We performed a pilot observational study collecting clinical data and performing ultrasound examinations on children diagnosed with P. falciparum malaria infection. The targeted ultrasound examination included measurement of optic nerve sheath diameter, color transcranial Doppler insonation of the cerebral vasculature, cardiac ultrasound, and abdominal ultrasound. SETTING: Pediatric acute care unit of Mulago Hospital in Kampala, Uganda. PATIENTS: Thirty-three hospitalized children between the ages of 6 months and 12 yrs with documented acute P. falciparum infection. INTERVENTION: Targeted bedside ultrasound examination. MEASUREMENTS AND MAIN RESULTS: Increased optic nerve sheath diameter was observed in one third of all patients with malaria and in 100% of the patients diagnosed with cerebral malaria. Although higher-than-normal cerebral blood flow velocities were demonstrated in three (25%) of 12 patients with severe anemia, most patients demonstrated a normal cerebral blood flow velocity, suggesting a blunted response to anemia. We did not find evidence of pulmonary hypertension by cardiac ultrasound, and cardiac function did not seem depressed, even among patients with severe anemia and lactic acidosis. Finally, spleen size as determined by palpation significantly overestimated the true incidence of splenomegaly as measured by ultrasound (48% and 24%, respectively). CONCLUSIONS: A targeted ultrasound examination focusing on optic nerve sheath diameter, color transcranial Doppler, cardiac ultrasound, and spleen size may prove useful for patient classification, risk stratification, research studies, and treatment monitoring in pediatric malaria. More studies should be done.

Derivation of a size-independent variable for scaling of cardiac dimensions in a normal paediatric population.

AIMS: It is general practice to correct cardiac chamber size for body size by the process of scaling or normalization. Normalization is most commonly performed using simple linear or isometric correction; however, there is increasing evidence that this approach may be flawed. Likewise, there is little agreement concerning the appropriate scaling variable (measure of body size) for normalization. Therefore, we aimed to establish the optimal method for correcting the differences in body size in a large population of echocardiographically normal paediatric subjects. METHODS AND RESULTS: We compared the relative ability of standard size variables including height (HT), body weight (BW), body mass index (BMI), and body surface area (BSA), in both isometric and allometric models, to remove the effect of body size in 4109 consecutive echocardiographically normal subjects<18 years of age, using the left atrial dimension (LAD) as a reference standard. Simple linear normalization resulted in significant residual correlations (r=-0.57 to -0.92) of the indexed value with the body size variable, the correlations with weight (WT) and BSA actually increasing. In contrast, correction by the optimal allometric exponent (AE) removed the effects of the indexed variable (residual correlations -0.01 to 0.01), with BW and BSA best removing the effects of all the measures of body size. CONCLUSION: Conventional linear correction for body size is inaccurate in children and paradoxically increases the relationship of the indexed parameter with WT and BSA. Conversely, correction using the optimal AE removes the effect of that variable, with WT best correction for all measures of body size.

Cor triatriatum: the utility of cardiovascular imaging.

A 44-year-old man with no known cardiac history presented with worsening dyspnea on minimal exertion. During follow-up, computed tomography angiography and echocardiography confirmed the incidental finding of cor triatriatum. As improvements in spatial and temporal resolution continue, cardiac computed tomography may become better suited to the dynamic imaging of anatomical defects in the heart, including, but not limited to, coronary artery disease.

Percutaneous transcatheter closure of patent foramen ovale in patients with paradoxical embolism.

BACKGROUND: Percutaneous transcatheter closure of patent foramen ovale (PFO) is used as an alternative to surgery or long-term anticoagulation for the treatment of patients with paradoxical embolism and PFO. METHODS AND RESULTS: We report the immediate and long-term clinical and echocardiographic outcome of 110 consecutive patients (58 males, mean age 47+/-14 years) who underwent transcatheter closure of PFO because of paradoxical embolism between 1995 and 2001. Procedural success, defined as successful deployment of the device and effective occlusion (no, or trivial, shunt after device placement), was achieved in all (100%) patients. There was no in-hospital mortality, 1 device migration requiring surgical intervention (0.9%), and 1 episode of cardiac tamponade (0.9%) requiring pericardiocentesis. A progressive increment in full occlusion was observed (44%, 51%, 66%, and 71% at 1 day, 6 months, and 1 and 2 years, respectively, after device placement). At a mean follow-up of 2.3 years, 2 patients experienced recurrent neurological events (1 fatal stroke and 1 transient ischemic attack), representing an annual risk of recurrence of 0.9%. In addition, 4 (3.6%) of the patients required reintervention for device malalignment or significant shunt. Kaplan-Meier analysis showed a freedom from recurrent embolic events and reintervention of 96% and 90% at 1 and 5 years, respectively. CONCLUSIONS: Transcatheter closure of PFO is a safe and effective therapy for patients with paradoxical embolism and PFO. It is associated with a high success rate, low incidence of hospital complications, and low frequency of recurrent systemic embolic events.

Effect of three-dimensional valve shape on the hemodynamics of aortic stenosis: three-dimensional echocardiographic stereolithography and patient studies.

OBJECTIVES: This study tested the hypothesis that the impact of a stenotic aortic valve depends not only on the cross-sectional area of its limiting orifice but also on three-dimensional (3D) valve geometry. BACKGROUND: Valve shape can potentially affect the hemodynamic impact of aortic stenosis by altering the ratio of effective to anatomic orifice area (the coefficient of orifice contraction [Cc]). For a given flow rate and anatomic area, a lower Cc increases velocity and pressure gradient. This effect has been recognized in mitral stenosis but assumed to be absent in aortic stenosis (constant Cc of 1 in the Gorlin equation). METHODS: In order to study this effect with actual valve shapes in patients, 3D echocardiography was used to reconstruct a typical spectrum of stenotic aortic valve geometrics from doming to flat. Three different shapes were reproduced as actual models by stereolithography (computerized laser polymerization) with orifice areas of 0.5, 0.75, and 1.0 cm(2) (total of nine valves) and studied with physiologic flows. To determine whether valve shape actually influences hemodynamics in the clinical setting, we also related Cc (= continuity/planimeter areas) to stenotic aortic valve shape in 35 patients with high-quality echocardiograms. RESULTS: In the patient-derived 3D models, Cc varied prominently with valve shape, and was largest for long, tapered domes that allow more gradual flow convergence compared with more steeply converging flat valves (0.85 to 0.90 vs. 0.71 to 0.76). These variations translated into differences of up to 40% in pressure drop for the same anatomic area and flow rate, with corresponding variations in Gorlin (effective) area relative to anatomic values. In patients, Cc was significantly lower for flat versus doming bicuspid valves (0.73 +/- 0.14 vs. 0.94 +/- 0.14, p < 0.0001) with 40 +/- 5% higher gradients (p < 0.0001). CONCLUSIONS: Three-dimensional valve shape is an important determinant of pressure loss in patients with aortic stenosis, with smaller effective areas and higher pressure gradients for flatter valves. This effect can translate into clinically important differences between planimeter and effective valve areas (continuity or Gorlin). Therefore, valve shape provides additional information beyond the planimeter orifice area in determining the impact of valvular aortic stenosis on patient hemodynamics.

Anesthetic management for transurethral resection of the bladder in a 74-year-old man with uncorrected tetralogy of Fallot.

We report a case of general anesthesia for transurethral resection of the bladder in a 74-year-old male patient with uncorrected tetralogy of Fallot. This case illustrates the pertinent pathophysiology of the complex cardiac lesion related to tetralogy of Fallot as well as the feasibility and issues with regard to the anesthetic management.

Can a teaching intervention reduce interobserver variability in LVEF assessment: a quality control exercise in the echocardiography lab.

OBJECTIVES: This study sought to determine whether a formalized teaching intervention could reduce the interobserver variability (IOV) in visual estimation of left ventricular ejection fraction (LVEF) within a group of sonographers and physicians with a spectrum of experience. BACKGROUND: Precise and reliable echocardiographic assessment of LVEF is necessary for clinical decision-making and minimizing duplicative testing. Skill in the visual estimation of LVEF varies depending on experience and is critical for corroborating EF quantification. IOV may also lead to inconsistency if multiple readers are assessing the EF on serial exams. METHODS: Fourteen cases of 2-dimensional echocardiograms were shown to 25 participants who estimated the EF based on a complete assessment of LV wall motion including parasternal, short-axis, apical, and subcostal views. The cases represented a spectrum of EF range, image quality, and clinical context. Following the initial interpretations, participants underwent a teaching intervention involving tutorial review of reference cases and group discussion of each case with determination of the EF guided by quantitative measure (biplane Simpson method). Three months after the teaching intervention, 14 new cases were shown to the 25 participants following the same methodology. RESULTS: IOV was quantified before and after the teaching intervention with the use of a 3-factor, nested analysis of variance. The factors were: observer, patient, and pre- and post-intervention (time). The analysis of variance showed that the intervention reduced the IOV for the 25 readers between the pre- and post-intervention assessments (F = 2.8, p = 0.007). The IOV decreased from ± 14% EF prior to intervention to ± 8.4% EF following intervention (a 40% reduction in IOV). CONCLUSIONS: In a large echocardiography laboratory with a wide range of training levels and experience, a simple, formalized teaching intervention can successfully diminish IOV of LVEF assessment. This intervention provides not only discrete quality measures, but also serves as a practical tool to document and improve quality of reporting, potentially reducing clinical inefficiencies and repeat testing.

Three-dimensional echocardiographic assessment of acquired left ventricular to right atrial shunt (Gerbode defect).

A 60-year-old man was readmitted 1 year after bioprosthetic aortic valve replacement for recurrent endocarditis. Transthoracic 2-dimensional color Doppler revealed a novel finding of a left-to-right shunt from the left ventricular outflow tract to the right atrium immediately superior to the septal leaflet of the tricuspid valve consistent with an acquired Gerbode defect. Real-time 3-dimensional echocardiography was used to accurately delineate the course of the shunt. To avoid overestimating right ventricular systolic pressure by mistaking such a shunt for an eccentric jet of tricuspid regurgitation, it is important to accurately differentiate the two. Real-time 3-dimensional echocardiography now provides rapid, detailed 3-dimensional appreciation of the origin and course of such shunts with easy facility of orienting views to the flows of interest by cropping. Such information can help design optimal surgical or catheter-based therapy.