Igor I. Tulevski

ECG determinants in adult patients with chronic right ventricular pressure overload caused by congenital heart disease: relation with plasma neurohormones and MRI parameters

Objective: To examine retrospectively the changes in ECG parameters over time and their correlation with other quantitative right ventricular (RV) function parameters in patients with chronic RV pressure overload caused by congenital heart disease. Methods: 48 patients with chronic RV pressure overload caused by the following congenital heart diseases were studied: nine with congenitally corrected transposition of the great arteries (TGA), 12 with surgically corrected TGA, and 27 with a subpulmonary pressure overloaded RV. QRS duration and dispersion were measured manually from standard ECG recorded twice within five years. RV end diastolic volume (EDV) and RV mass were determined by magnetic resonance imaging. Brain natriuretic peptide (BNP) plasma concentrations were measured. Results: QRS duration and QRS dispersion increased in all patient groups during the follow up period. QRS duration increased significantly in the congenitally corrected TGA (p = 0.04) and the subpulmonary pressure overloaded RV groups (p = 0.01). QRS dispersion increased significantly in patients with surgically corrected TGA (p = 0.03) and in the subpulmonary pressure overloaded RV group (p = 0.02). A significant correlation was found between QRS duration and RVEDV (r = 0.71, p < 0.0001). RV mass was significantly correlated with QRS duration in patients with tetralogy of Fallot (r = 0.67, p = 0.01). Mean (SD) plasma brain natriuretic peptide concentrations (6.6 (5.4) pmol/l) were increased compared with normal reference values but no correlation was found with ECG parameters or RV systolic pressure. No malignant arrhythmia or sudden death occurred. Conclusions: ECG parameters worsened gradually in asymptomatic or minimally symptomatic patients with chronic RV pressure overload, regardless of the nature of their congenital heart disease. In all patients, a significant positive correlation was found between QRS duration and RVEDV. In patients with tetralogy of Fallot there was also a correlation between QRS duration and RV mass.

Quantitative assessment of the pressure and volume overloaded right ventricle: imaging is a real challenge

Physicians are facing an increasing number of patients with right ventricular (RV) overload due to congenital heart disease. Adult patients with congenital heart disease are emerging as a new and continuously growing population. Improvements in medical care, surgical techniques, and closer follow-up have dramatically improved life expectancy in this group of patients. However, in a substantial part of these patients, the RV is or has been subjected to chronic pressure and/or volume overload (Figure 1). The long-term prognosis of these patients is unknown and mainly dependent on factors such as RV (dys)function, the occurrence of RV failure [1], and rhythm disorders [2–4]. There is much controversy regarding the long term outcome of RV function under these circumstances [4–6]. Some patients are asymptomatic [3, 7, 8], while others are in need of frequent medical care [9]. Accordingly, their life expectancy is highly variable and expressed over a wide range [7, 10– 13]. Because assessment of RV function is a difficult task, current evaluation of these patients is mainly based on qualitative parameters [14]. The lack of quantitative determinants for RV function hampers physicians to estimate the appropriate time for surgical or medical intervention in order to prevent irreversible RV failure. Management of these patients would be improved by establishing accurate noninvasive quantitative RV function determinants and to relate them to the already existing qualitative RV function determinants. The combined information could thus be implemented in daily clinical practice. This paper will review the imaging modalities for RV function determination in congenital heart disease.

Right ventricular function in congenital cardiac disease: noninvasive quantitative parameters for clinical follow-up

Right ventricular function is of great importance in patients with both acute and chronic ventricular overload. The early detection of right ventricular dysfunction may have an impact on therapeutic decision making, helping to prevent or further delay functional deterioration of the right ventricle. In patients with right ventricular overload due to congenital cardiac diseases, dobutamine stress testing combined with magnetic resonance imaging, electrocardiographic changes, and monitoring of concentrations of plasma brain natriuretic peptide are very suitable parameters for the early detection of ventricular dysfunction, and should therefore be used in the follow-up of these patients. It is apparent that no single measurement of anatomy or function can ever adequately describe the form or performance of the right ventricle. Rather, we should be looking more towards an integrated approach of different parameters for right ventricular function. The quantitative parameters described in this study can serve this purpose. The strong correlation found between these non-invasive and independent parameters encourages their clinical implementation.

Vascular rings and pulmonary arterial sling: from respiratory collapse to surgical cure, with emphasis on judicious imaging in the hi-tech era

t Vascularr rings, and pulmonary arterial slings, are relatively rare vascular anomalies, but are importantt lesions to recognize, since if left untreated, patients may experience life-threatening respiratoryy compromise and near death episodes. Surgical therapy, however, is almost alwayss curative. As most infants and children initially present with respiratory symptoms, theyy are frequently referred to and managed by pulmonologists and otorinolaryngologists beforee being presented to a surgical team. A high index of suspicion is necessary to direct thee diagnostic work-up, which may rapidly reveal the correct diagnosis, and allow for timely surgicall repair. Inn the current era, an increasing number of diagnostic procedures are performed preoperatively, oftenn yielding repetitive or overlapping information. Nonetheless, the hi-tech escalade of new imageryy has not provided better results, and is substantially more expensive. Thiss article reviews the history of surgical correction of rings and slings, the standard surgical approaches,, the results, and the long-term outcomes. Emphasis is given on a suggested algorithm forr diagnostic work-up. If followed, this may avoid the frequent unnecessary delay, along with superfluouss investigations in achieving a correct diagnosis, and lead more rapidly to successful surgicall treatment. Vascularr rings and slings Historicall Background Althoughh the earliest description of tracheal or esophageal compression by a vascular structure wass first given in 1737 by Hommel , over two centuries elapsed before the first surgical correctionn of a complete vascular ring was performed, by Robert Gross in 1945 -. In his landmarkk article, he described the technique for repair of double aortic arch through a left anteriorr thoracotomy. He described two other cases, another double aortic arch, and a complete ringg formed by a right aortic arch with retroesophageal left subclavian artery and left-sided arteriall ligament -. Gross subsequently performed the first successful operations for partial vascularr rings, namely an aberrant right subclavian artery causing dysphagia lusoria in 1946, followedd by suspension of the brachiocephalic artery to the sternum in 1948 Williss Potts was the first to describe, in 1954, a successful operation for pulmonary arterial sling,, performed at Childrens Memorial Hospital in Chicago This was achieved through a rightt thoracotomy, with division and reimplantation of the left pulmonary artery anterior to thee trachea. The first successful combined repair of pulmonary arterial sling and complete tracheall rings with a pericardia! patch using cardiopulmonary bypass was also performed at Childrenss Memorial Hospital, by Farouk Idriss in 1982 Since then, surgical approaches and techniquess have varied little, and the minor controversies in treating the syndromes of vascular compressionn lie more among diagnostic preferences and surgical timing. Symptomss and Diagnostic Work-up AA combination of respiratory symptoms is often the presenting mode for vascular rings. They includee stridor, a seal-bark cough, asthma, recurrent pneumonia, respiratory distress, cyanosis, andd apnea. Complete vascular rings present at a younger age and more severely. They are moree commonly associated with the seal-bark cough, which is a typical early finding in patientss with double aortic arch Apnea is prominent in patients with compression from the brachiocephalicc artery, and in those with complete tracheal rings. Patients with compression producedd by the brachiocephalic artery often have a characteristic posture, with opisthotonos andd hyperextension of the head Dysphagia and choking episodes occur in older children subsequentt to intake of solid food, or inadvertent swallowing of miscellaneous objects . Feedingg difficulties in general may lead to failure to thrive with concomitant stunting of weight Unfortunately,, the diagnostic work-up is frequently uncoordinated, and many examinations

Detection of Legionella pneumophila Serogroup 1 Antigen in Bronchoalveolar Lavage Fluid by an Immunochromatographic Assay

Recently, an immunochromatographic assay for rapid qualitative detection of Legionella pneumophila serogroup 1 antigen in urine specimens has become available (NOW Legionella urinary antigen test; Binax, Portland, Maine). We have previously shown that this test is of clinical value in providing a rapid diagnosis of Legionnaires disease, especially in patients with severe community-acquired pneumonia (CAP) in an outbreak setting (5). There are no reports on the applicability of the test to specimens other than urine. Here we report results from a 32-year-old human immunodeficiency virus (HIV)-infected man hospitalized with CAP of the right upper lobe. Bronchoalveolar lavage (BAL) was performed on the third day of admission because the patient did not respond to empirical therapy with amoxicillin. Gram staining of the BAL fluid revealed no apparent bacterial pathogens. Ziehl-Neelsen staining showed no acid-fast bacteria. Giemsa and toluidine blue stainings were negative for fungi. A urine specimen obtained on the fifth day of admission tested positive with the NOW Legionella urinary antigen test. At that time, culture of the BAL fluid yielded penicillin-resistant Streptococcus pneumoniae and β-lactamase-producing Haemophilus influenzae. Buffered charcoal yeast extract (BCYE) agar plates had been incubated for less than 48 h and did not show growth of Legionella spp. Subsequently, the pellet and supernatant of the stored BAL fluid were tested with the NOW Legionella urinary antigen test, and both gave a positive result. To rule out cross-reactivity, suspensions of the S. pneumoniae and H. influenzae isolates of the patient were tested. Both suspensions tested negative. The following day, an indirect immunofluorescent antibody (IFA) test for L. pneumophila (MONOFLUO Legionella pneumophila IFA test kit; Bio-Rad, Munich, Germany) was performed with the pellet of the BAL fluid and small colonies growing at that time on the BCYE agar plates. Both preparations showed brightly fluorescent rods. The strain did not grow on BCYE in the absence of cysteine and was identified as L. pneumophila serogroup 1 by serogrouping techniques (Dryspot Legionella latex test; Oxoid, Hampshire, United Kingdom). Antibacterial therapy was switched to levofloxacin and cefotaxime. The patient was discharged from the hospital in good condition after 14 days. n nA preliminary evaluation of specificity of this application of the NOW Legionella urinary antigen test was conducted with BAL fluids from five pneumonia patients. L. pneumophila serogroup 1 antigen was not detected in pellets or supernatants of centrifuged BAL fluids, while culture yielded no Legionella spp. Conventional microbiological methods did reveal other microorganisms: e.g., H. influenzae, Serratia marcescens, Pseudomonas aeruginosa, Corynebacterium spp., coagulase-negative staphylococci, Candida spp., and Pneumocystis carinii. n nThe NOW Legionella urinary antigen test detected L. pneumophila serogroup 1 antigen in BAL fluid from an HIV-infected patient with culture-proven Legionnaires disease. Application of the test to specimens other than urine might prove useful for rapid diagnosis of Legionnaires disease. This may be especially true for anuric patients. End-stage renal disease is identified as risk factor for legionellosis, and acute renal failure is a known complication of Legionnaires disease (1-3). The test might also prove useful for patients with extrapulmonary manifestations of L. pneumophila serogroup 1 infection—e.g., pericarditis, which often presents without overt pneumonia (4). While our observation seems promising, additional clinical observations are needed to evaluate the sensitivity and specificity of the test with specimens other than urine.