Recovering an endangered frog species through integrative reproductive technologies.

The establishment and management of ex situ breeding and assurance populations around the globe are meant to provide short-term solutions to the formidable loss of amphibian diversity presently occurring. Large multi-scaled facilities, such as zoos and aquariums, can provide the infrastructure to safeguard species and populations. However, often even large, economically viable facilities lack the knowledge to efficiently cater to the plethora of environmentally controlled physiological strategies that amphibians possess. Anurans present a class of amphibians that have often been viewed as easy to maintain ex situ. However, while adult survival may be relatively successful it is rarely accompanied by good reproductive output, health, and fitness. Even more conspicuous is the low survivorship of offspring produced ex situ once they are translocated back into the wild. The mountain yellow-legged frog (R. muscosa) ex situ breeding program EBP is a prime example of the challenges that amphibians EBPs face. Although more research is needed, the R. muscosa program has increased reproductive output and health of its colony by incorporating reproductive technologies and strategic genetic management in conjunction with a greater understanding of the species' natural history, to produce and translocate viable animals each year. This paper highlights the EBPs past decade of research featuring the program's contribution to building empirical, multidisciplinary approaches that boost the robustness of an endangered species, by safeguarding existing genetic diversity and maximizing fitness and survival outcomes.

Economic evaluation of online computerised cognitive-behavioural therapy without support for depression in primary care: randomised trial.

BACKGROUND: Evidence about the cost-effectiveness and cost utility of computerised cognitive-behavioural therapy (CCBT) is still limited. Recently, we compared the clinical effectiveness of unsupported, online CCBT with treatment as usual (TAU) and a combination of CCBT and TAU (CCBT plus TAU) for depression. The study is registered at the Netherlands Trial Register, part of the Dutch Cochrane Centre (ISRCTN47481236). AIMS: To assess the cost-effectiveness of CCBT compared with TAU and CCBT plus TAU. METHOD: Costs, depression severity and quality of life were measured for 12 months. Cost-effectiveness and cost-utility analyses were performed from a societal perspective. Uncertainty was dealt with by bootstrap replications and sensitivity analyses. RESULTS: Costs were lowest for the CCBT group. There are no significant group differences in effectiveness or quality of life. Cost-utility and cost-effectiveness analyses tend to be in favour of CCBT. CONCLUSIONS: On balance, CCBT constitutes the most efficient treatment strategy, although all treatments showed low adherence rates and modest improvements in depression and quality of life.

Right atrial compression in postoperative cardiac patients: detection by transesophageal echocardiography.

Four patients developed hypotension after heart surgery. Hemodynamic measurements revealed elevated right atrial pressure with normal pulmonary capillary wedge pressure. Conventional transthoracic two-dimensional echocardiography was technically suboptimal for detection of pericardial effusion. In each patient transesophageal echocardiography demonstrated significant compression of the right atrium by a localized mass. At reoperation atrial compression by an organized hematoma was found and in each instance successfully drained. Thus, transesophageal echocardiography is superior to transthoracic echocardiography in evaluating critically ill postoperative hypotensive patients and can differentiate isolated right atrial tamponade from other causes of hemodynamic deterioration such as prosthetic valve dysfunction or left ventricular systolic dysfunction, or both.

Cardiac manifestations of acquired immunodeficiency syndrome.

Acquired immunodeficiency syndrome is a serious problem worldwide. Recent advances in the knowledge about human immunodeficiency virus (HIV) replication and the treatment of HIV infection have improved survival in HIV patients. Because of the longer survival in HIV patients, the more manifestations of late-stage HIV infection will be seen, including HIV-related cardiac diseases. The common cardiac manifestations in patients with the acquired immunodeficiency virus are pericardial effusion, myocarditis, dilated cardiomyopathy, endocarditis, pulmonary hypertension, malignant neoplasms, and drug-related cardiotoxicity. This review focuses on these cardiac manifestations in patients with the acquired immunodeficiency syndrome.

Meta-analysis of 143 reported cases of aortic intramural hematoma.

Aortic intramural hematoma (IMH) is a clinical condition that has still not been completely defined. We conducted a meta-analysis of reported cases and analyzed the demographic profiles, imaging modalities, pathologic sites, and treatment strategies in relation to outcome in 143 patients with IMH. We performed an English language search of Medline for manuscripts with the keywords "aortic diseases," "aorta AND hematoma," and "intramural hematoma." Data from 143 reported cases were extracted. IMH of the aorta has a reported incidence of 5% to 20% among patients with acute aortic syndromes and a mortality rate of 21%. Most patients were men (61%) and median age was 68 years (range 15 to 88). Hypertension was a predisposing factor in 53% of the patients. Most patients had chest and/or back pain (80%). Transesophageal echocardiography, computer tomographic scan, or magnetic resonance imaging may be effectively used to diagnose this condition. There is no difference in the overall mortality rates in Stanford type A versus type B patients. Patients with Stanford type A IMH who underwent surgery, compared with those who underwent medical management, had a significantly better prognosis (14% vs 36% mortality, respectively, p < 0.02). Patients in Stanford group A who received medical treatment had a higher mortality rate than those in group B who received medical treatment (36% vs 14% mortality respectively, p < 0.02). In type B patients, medical and surgical outcomes were similar.

Incidence of bleeding complications associated with abciximab use in conjunction with thrombolytic therapy in patients requiring percutaneous transluminal coronary angioplasty.

The use of abciximab after full-dose failed thrombolytics within 15 hours of acute myocardial infarction significantly increases the risk of major bleeding complications.

Utility of transesophageal echocardiography in the conservative management of prosthetic valve endocarditis.

Prosthetic valve endocarditis is a formidable complication following cardiac valve replacement. Surgical intervention has resulted in a significant reduction in mortality when certain complications prevail. We report two such cases of prosthetic valve endocarditis in which the use of transesophageal echocardiography permitted close surveillance during medical therapy and thus avoided the need for surgical intervention. Therefore, with the improved ability to monitor disease progression with transesophageal echocardiography, nonsurgical management of prosthetic valve endocarditis remains an option.

Coronary vasospasm secondary to labetalol in a patient with aortic dissection.

A 66-year-old hypertensive woman presented with epigastric and scapular pain on the basis of type 3 aortic dissection. Appropriate therapy with a combined alpha-adrenergic and beta-adrenergic antagonist agent prevented further ongoing dissection and amelioration of symptoms. On day 5, an episode of coronary vasospasm occurred presumably due to beta-blockade with unopposed alpha-adrenergic activity.

The utility of transesophageal echocardiography in the management of renal cell carcinoma with intracardiac extension.

The accurate assessment of the distal extent of vena caval invasion of renal cell carcinoma into the hepatic veins, inferior vena cava, and right atrium is critical before surgical resection. We present two cases of renal carcinoma with vena caval extension in which preoperative transesophageal echocardiography accurately assessed tumor extent and guided surgical therapy. The role of transesophageal echocardiography in comparison to other diagnostic modalities is discussed.

Flow patterns in dilated cardiomyopathy: a pulsed-wave and color flow Doppler study.

In 48 patients with dilated cardiomyopathy, pulsed-wave and color Doppler examination were performed. In addition, 14 normal patients served as control subjects. Peak inflow velocity at the level of the mitral valve, middle left ventricle, and apex and outflow velocity at the level of the apex, middle left ventricle, and subaortic area were measured. In normal patients there was brisk propagation of inflow velocity to the apex. Patients with dilated cardiomyopathy demonstrated delayed propagation and prolongation of the duration of inflow compared with control subjects (p less than 0.04). Continuous apical flow was visualized in 25% of dilated cardiomyopathies and in no normal patients. Apical velocities were significantly increased in cardiomyopathies with significant mitral regurgitation. Outflow velocities were decreased in dilated cardiomyopathy. In patients with dilated cardiomyopathy and apical dyskinesis, flow directed toward the base was measured in the middle left ventricle during isovolumic relaxation secondary to dyskinetic rebound. Patterns of abnormal flow in dilated cardiomyopathies are readily apparent by color M-mode and two-dimensional color Doppler.

Transesophageal echocardiographic evaluation of a transthoracic echocardiographic pitfall: a diaphragmatic hernia mimicking a left atrial mass.

Diaphragmatic hernia may mimic a left atrial mass when imaged by transthoracic echocardiography. In this case study we emphasize the value of transesophageal echocardiography in clarifying the cause of this apparent atrial mass.

Superior vena caval thrombosis detected by transesophageal echocardiography.

Three patients with clinical suspicion of bacterial endocarditis, induced by either pacemaker or indwelling catheter, underwent transesophageal echocardiography. High short-axis cuts through the great vessels, however, revealed the presence of superior vena caval thrombus in all three patients. Transesophageal echocardiography is more sensitive in establishing the diagnosis of superior vena caval thrombus than surface echocardiography. Comparison of transesophageal echocardiography with other diagnostic modalities is needed in assessing its overall sensitivity and specificity.

Patent foramen ovale: a nonfunctional embryological remnant or a potential cause of significant pathology?

A patent foramen ovale (PFO) is an embryological remnant found in 27% of adults. It is a potential right-to-left intracardiac shunt. Shunting may be the result of reversal in the interatrial pressure gradient or abnormal streaming of blood in the right atrium. The pathologic consequences of right-to-left shunting include hypoxemia and paradoxical embolism. PFO may exacerbate preexisting hypoxemia or be its primary cause. Paradoxical embolism through a PFO is well documented. Its role in cryptogenic stroke remains controversial. A PFO may be detected by both invasive and noninvasive techniques. Contrast transesophageal echocardiography with provocative maneuvers is the diagnostic method of choice allowing visualization of the shunt. Patients with cryptogenic stroke should be screened for a PFO. If detected, noninvasive studies for deep vein thrombosis are recommended. Treatment must be tailored to the presentation. Surgical or transcatheter closure is recommended for hypoxemia. Prevention of venous embolism (air or thrombus) with or without closure of the PFO is recommended for paradoxical embolism.

Long-term follow-up of mitral paraprosthetic regurgitation by transesophageal echocardiography.

Paravalvular regurgitation (PVR) is an uncommon complication of mitral valve replacement (MVR). Although severe PVR is almost always repaired immediately when recognized during surgery, there are little data available on the management of patients with mild and moderate PVR. This study includes eight patients with mild (n = 6) and moderate (n = 2) PVR identified by transesophageal echocardiography at the time of MVR who were treated conservatively. Clinical and echocardiographic follow-up was obtained at a mean of 16.3 months. Two of six patients with mild PVR at the time of MVR and two of two patients with moderate PVR at the time of MVR deteriorated clinically and echocardiographically over time. We suggest that moderate PVR should be corrected at the time of valve-replacement surgery, if this can be performed without high operative risk. Mild PVR should probably also be repaired, if this can be performed at low risk, because some will progress. Patients left with mild PVR after surgery, or patients in whom PVR is recognized only after surgery, should be followed up carefully with serial clinical and echocardiographic examinations.

Transesophageal echocardiography in the diagnosis of the persistent left superior vena cava.

Three patients with suspected persistent left superior vena cava (PLSVC) diagnosed by transthoracic echocardiography underwent single-plane transesophageal echocardiography. In all three patients transverse cuts through right atrium and coronary sinus demonstrated the presence of PLSVC. Agitated contrast injection into the left antecubital vein opacified PLSVC and coronary sinus in all cases. Transesophageal echocardiography is superior to transthoracic echo in the diagnosis of PLSVC and associated cardiac anomalies.

Cardiac sarcoidosis masquerading as a metastatic tumor: the role of transthoracic and transesophageal echocardiography.

We present an unusual case of biopsy-proven myocardial sarcoidosis in which the transthoracic and transesophageal echocardiographic findings suggested metastatic tumor involvement of the myocardium and pericardium. The pathologic, clinical, and echocardiographic features of cardiac sarcoidosis are reviewed, with emphasis on the role of echocardiography.

A novel approach to calculation of mean mitral valve gradient by Doppler echocardiography.

The Doppler-derived mean mitral valve gradient (DeltaP(M)) based on the simplified Bernoulli equation requires computerized integration of the Doppler signal and evaluation by a technician with the use of special equipment. We have noted empirically that the DeltaP(M) can be derived by the equation DeltaP(M) = (P(P) - P(T)) / 3 + P(T). Peak (P(P)) and trough (P(T)) pressures are derived from the simplified Bernoulli equation (P = 4V(2)). This equation can be used by the experienced observer to calculate the mean mitral valve gradient without specialized equipment. The purpose of this study is to validate the above empirically derived equation in patients with mitral stenosis. We retrospectively reviewed 41 consecutive studies done at our institution from October 1, 1997, through September 30, 1998, in which mean mitral valve gradient was assessed. Each study was reviewed and the DeltaP(M), P(P), and P(T) were measured for 3 beats by using the software package on an HP Sonos 2500. DeltaP(M) was also calculated with our formula. A linear regression model was used to compare the results of the measured versus the calculated DeltaP(M). The following sub-categories were also evaluated: transthoracic studies (TTE), transesophageal studies (TEE), native valve gradients (NV), prosthetic valve gradients (PV), sinus rhythm (SR), and atrial fibrillation (AF). The results of the regression analysis of the entire population of mean versus calculated DeltaP(M) are n = 41, r = 0.99, P <.001, and standard error of the estimate (SEE) = 0.67. The regression results for the subgroups are as follows: TTE: n = 30, r = 0.99, P <.001, SEE = 0.51; TEE: n = 11, r = 0.99, P <.001, SEE = 59; NV: n = 26, r = 0.99, P <.001, SEE = 0.59; PV: n = 15, r = 0.98, P <.001, SEE = 0.84; SR: n = 23, r = 0.99, P <.001, SEE = 0.58; and AF: n = 18, r = 0.98, P <.001, SEE = 0.82. In conclusion, the simple formula that we have derived is an accurate method for calculation of mean mitral valve gradient, and it is accurate over multiple subgroups. Furthermore, the formula allows visual verification of mean mitral gradient without specialized software.

Mycotic aneurysm of the descending thoracic aorta: the role of transesophageal echocardiography.

Mycotic aneurysms of the aorta are prone to rupture. Thus rapid and accurate diagnosis is essential so that surgical repair can be undertaken. We report a case of mycotic aortic aneurysm caused by mitral valve endocarditis. The aneurysm situated at the junction of the thoracoabdominal aorta was readily detected by transesophageal echocardiography. Computed tomography and aortography were complementary to transesophageal echocardiography in establishing the diagnosis. The patient underwent successful repair and acute inflammation of the aneurysm was present at histologic examination.

Significant mitral regurgitation is protective against left atrial spontaneous echo contrast and thrombus as assessed by transesophageal echocardiography.

This retrospective study examines whether a relationship exists between the severity of mitral regurgitation (MR) and the presence of left atrial spontaneous echo contrast and/or thrombus (SEC/THR) as assessed by transesophageal echocardiography in 427 consecutive patients. Clinical data were evaluated in 316 of these patients. Nine percent of patients with MR < or = 2+ versus < 1% of those with MR > or = 3+ had SEC/THR (p < 0.03). Atrial fibrillation, left ventricular dysfunction, mitral stenosis, and mitral valve prosthesis were demonstrated to be independent positive predictors of left atrial SEC/THR, whereas MR > or = 3+ was an independent negative predictor of SEC/THR. SEC/THR was less common in patients with MR > or = 3+ than in patients with MR < or = 2+ for any given number of independent positive predictors of SEC/THR. This relationship did not hold true in patients with a mechanical mitral prosthetic valve. Clinical data revealed a trend towards a lower prevalence of stroke or transient ischemic attacks in patients with MR > or = 3+. Stroke and transient ischemic attacks were significantly more common in patients with SEC/THR (p < 0.001). We suggest that significant MR may be protective against the formation of left atrial SEC/THR.

Evaluation of hemolysis in patients with prosthetic heart valves.

The primary mechanism and most common cause of hemolytic disease in patients with prosthetic heart valves are mechanical trauma to red blood cells and paraprosthetic valvular regurgitation, respectively. Presenting features in patients with this condition include anemia, congestive heart failure, fatigue, jaundice, dark urine, and a regurgitant murmur. Various laboratory studies can be utilized to diagnose hemolytic anemia and to assess the severity of hemolysis. Transthoracic echocardiography, transesophageal echocardiography, and Doppler studies including color Doppler are useful imaging methods to assess valve function. Treatment is usually medical (oral iron); however, in patients with paravalvular regurgitation, surgery is often required to correct the anemia.