Transesophageal echocardiography in patients with cryptogenic cerebral ischemia.

BACKGROUND: In about one third of all patients with cerebral ischemia, no definite cause can be identified (cryptogenic stroke). In many patients with initially suspected cryptogenic stroke, however, a cardiogenic etiology can eventually be determined. Hence, the aim of this study was to describe the prevalence of abnormal echocardiographic findings in a large number of these patients. METHOD: Patients with cryptogenic cerebral ischemia (ischemic stroke, IS, and transient ischemic attack, TIA) were included. The initial work-up included a neurological examination, EEG, cCT, cMRT, 12-lead ECG, Holter-ECG, Doppler ultrasound of the extracranial arteries, and transthoracic echocardiography. A multiplane transeophageal echocardiography (TEE, including i.v. contrast medium application [Echovist], Valsalva maneuver) was performed in all patients RESULTS: 702 consecutive patients (380 male, 383 IS, 319 TIA, age 18-90 years) were included. In 52.6% of all patients, TEE examination revealed relevant findings. Overall, the most common findings in all patients were: patent foramen ovale (21.7%), previously undiagnosed valvular disease (15.8%), aortic plaques, aortic valve sclerosis, atrial septal aneurysms, regional myocardial dyskinesia, dilated left atrium and atrial septal defects. Older patients (> 55 years, n = 291) and patients with IS had more relevant echocardiographic findings than younger patients or patients with TIA, respectively (p = 0.002, p = 0.003). The prevalence rates of PFO or ASD were higher in younger patients (PFO: 26.8% vs. 18.0%, p = 0.005, ASD: 9.6% vs. 4.9%, p = 0.014). CONCLUSION: A TEE examination in cryptogenic stroke reveals contributing cardiogenic factors in about half of all patients. Younger patients had a higher prevalence of PFO, whereas older patients had more frequently atherosclerotic findings. Therefore, TEE examinations seem indicated in all patients with cryptogenic stroke - irrespective of age - because of specific therapeutic consequences.

Evaluation of longitudinal and radial two-dimensional strain imaging versus Doppler tissue echocardiography in predicting long-term response to cardiac resynchronization therapy.

INTRODUCTION: Cardiac resynchronization therapy (CRT) leads to hemodynamic and clinical improvement in patients with heart failure. This study compares the new technique of 2-dimensional (2D) strain imaging with Doppler tissue imaging (DTI) in the prediction of the long-term response to CRT. METHODS: In all, 38 patients with heart failure (New York Heart Association II-III, QRS > 120 milliseconds, left ventricular ejection fraction < 0.35) received CRT and echocardiographic evaluation with a mean follow-up of 9.4 months. RESULTS: Of the patients, 47.4% were hemodynamic responders to long-term CRT. In the responder group, the maximum delay in the longitudinal and radial 2D strain in the basal segments and the maximum delay in the DTI peak systolic myocardial velocities but not DTI strain decreased. In receiver operating characteristic analysis, the baseline delay of DTI peak velocities predicts improvement after CRT, whereas baseline 2D- and DTI-strain measurements fail to predict a long-term response to CRT. CONCLUSION: Although there is a significant decrease in longitudinal and radial 2D strain-derived delays after CRT, the resulting predictive value is not superior to DTI.

Does contrast echocardiography induce increases in markers of myocardial necrosis, inflammation and oxidative stress suggesting myocardial injury?

BACKGROUND: Contrast echocardiography is a precise tool for the non-invasive assessment of myocardial function and perfusion. Side effects of contrast echocardiography resulting from contrast-agent induced myocardial micro-lesions have been found in animals. The goal of this study is to measure markers of myocardial necrosis, inflammation and oxidative stress in humans to evaluate potential side-effects of contrast echocardiography. METHODS: 20 patients who underwent contrast echocardiography with Optison as the contrast medium were investigated. To evaluate myocardial micro-necrosis, inflammation and oxidative stress, cardiac troponin I (cTnI), tumor necrosis factor-alpha (TNF-alpha), interleukin (IL)-6, -8 and thiobarbituric acid reactive substances (TBARS) were measured at baseline and at 2, 4, 8 and 24 hours after contrast echocardiography. RESULTS: At baseline, 50% of the patients had cTnI and TBARS values outside the reference range. TNF-alpha, IL-6, IL-8 levels were within the reference range. Patients with cTnI above the RR clustered to significantly higher levels of TNF-alpha and IL-6. After contrast echocardiography, no statistically significant increase of cTnI, cytokines and TBARS was found. However, for nearly 50% of the patients, the intra-individual cTnI kinetics crossed the critical difference (threefold of methodical variation) which indicates a marker increase. This was neither predicted by the baseline levels of the cytokines nor the markers of oxidative stress. CONCLUSION: There are no clinically relevant increases in serum markers for micro-necrosis, inflammation and oxidative stress in humans after contrast echocardiography. Future studies have to address whether cTnI increase in some patients represent a subset with increased risk for side effects after contrast echocardiography.

High concordance of invasive and echocardiographic mean pressure gradients in patients with a mechanical aortic valve prosthesis.

BACKGROUND AND AIM OF THE STUDY: Conflicting data exist regarding the accuracy of echocardiographic Doppler gradients compared to invasive pressure gradients in the hemodynamic assessment of patients with prosthetic aortic valves. The study aim was to determine the correlation between these measurements for mechanical single- and double-leaflet aortic valve prostheses in vivo. METHODS: Forty-four patients with an aortic valve prosthesis were included in this prospective study. Transthoracic echocardiography was performed immediately before the invasive measurements. Left ventricular pressure measurements were achieved by either atrial transseptal puncture and antegrade, transmitral left ventricular catheterization or--in the case of mitral valve replacement--direct left ventricular puncture. RESULTS: Comparison of echocardiographic and invasive mean pressure gradients of all examined aortic prosthetic valves revealed a Pearson correlation r = 0.59 (p < 0.001). The mean pressure gradient was overestimated by 7.4 mmHg with echocardiography. Classifying patients into clinically relevant categories (mild, moderate, severely increased pressure gradient) resulted in a kappa value of 0.72 and an agreement of 86.4%. There was no relevant difference between single- and double-leaflet valves. CONCLUSION: A high concordance was found between echocardiographic and invasive mean pressure gradients in vivo. Invasive measurements of the prosthetic valve gradients therefore seem to be indicated only in patients with contradictory echocardiographic and clinical findings.

Tissue Doppler echocardiography and biventricular pacing in heart failure: patient selection, procedural guidance, follow-up, quantification of success.

Asynchronous myocardial contraction in heart failure is associated with poor prognosis. Resynchronization can be achieved by biventricular pacing (BVP), which leads to clinical improvement and reverse remodeling. However, there is a substantial subset of patients with wide QRS complexes in the electrocardiogram that does not improve despite BVP. QRS width does not predict benefit of BVP and only correlates weakly with echocardiographically determined myocardial asynchrony. Determination of asynchrony by Tissue Doppler echocardiography seems to be the best predictor for improvement after BVP, although no consensus on the optimal method to assess asynchrony has been achieved yet. Our own preliminary results show the usefulness of Tissue Doppler Imaging and Tissue Synchronization Imaging to document acute and sustained improvement after BVP. To date, all studies evaluating Tissue Doppler in BVP were performed retrospectively and no prospective studies with patient selection for BVP according to echocardiographic criteria of asynchrony were published yet. We believe that these new echocardiographic tools will help to prospectively select patients for BVP, help to guide implantation and to optimize device programming.

Percutaneous closure of interatrial communications in adults - prospective embolism prevention study with two- and three-dimensional echocardiography.

BACKGROUND: Patients with interatrial communications after paradoxical embolic events are at risk for recurrent thromboembolism. We hypothesized that transcatheter closure of the defects would result in long-term prevention of systemic embolism and performed clinical and echocardiographic follow-up. METHODS: We included 161 patients (mean age 46.8 +/- 11 years, 83 females) with patent foramen ovale or atrial septal defect and at least one documented paradoxical systemic thrombembolic event and/or a large atrial shunting. RESULTS: The implantation procedure was successfully performed without major complications in all patients and minor complications in 2.5%. Two and / or three dimensional echocardiography was performed before and after 4 weeks and 12 months using a multiplane transoesophageal probe. After 4 weeks and 6 months two patients had minimal shunting. These residual defects were closed with a second device implantation without shunting after further 4 weeks. During a follow-up of 324.3 patient years (range, 13 to 19 months), recurrent embolic events occurred in only 1 patient (0.6%). CONCLUSION: After primary paradoxical systemic embolism, results of transcatheter occlusion of the interatrial communications are dependent on the closure device system and can prevent further secondary embolic events for up to 1 year after the percutaneous closure. Three dimensional echocardiography provides dynamic features of the defects and the post closure status and may lead to an improved understanding and diagnosis of the interatrial defect.

Treatment of secondary pulmonary hypertension with bosentan and its pharmacokinetic monitoring in ESRD.

Pulmonary hypertension (PH) is a rare disease with a very poor prognosis. Certain pharmacologic approaches, which reduce pulmonary arterial pressure (PAP) and thereby prevent end-stage cardiopulmonary failure, have been used during recent years. Endothelin-1 has been found to be involved in the pathogenesis of PH. The dual endothelin-receptor antagonist, bosentan, was recently approved for the treatment of pulmonary arterial hypertension. The drug is mainly cleared by hepatic elimination. Severe renal dysfunction does not affect the single-dose pharmacokinetics of bosentan to a clinically relevant extent. Whether renal replacement therapy, however, interferes with the pharmacokinetics of bosentan is unknown. The authors report on the use of bosentan (125 mg twice daily) and its pharmacokinetic monitoring in a 19-year-old woman with PH and end-stage renal disease secondary to scleroderma. Treatment was well tolerated without drug-specific adverse effects. After 12 months of treatment, pulmonary arterial pressure had normalized (48 mm Hg before start of treatment, 27 mm Hg at last follow-up). On the basis of analyzing samples from Genius-hemodialysis by a liquid chromatography assay with tandem mass spectrometry detection, the authors determined the bosentan dialysis clearance to be as low as 3.5 mL/min. Bosentan for the treatment of secondary PH seems to be safe as well as effective in end-stage renal disease patients and no adjustment of the bosentan dosing regimen appears necessary.

Diagnostic accuracy of new handheld echocardiography with Doppler and harmonic imaging properties.

BACKGROUND: The first generation of handheld echocardiography devices was evaluated with divergent results because of inherent technical limitations. New handheld devices with continuous/pulsed wave Doppler and tissue harmonic imaging were introduced recently. In this study, comparisons were drawn among standard echocardiography, invasively measured systolic pulmonary artery pressure, and these new devices. OBJECTIVE: We sought to evaluate new handheld echocardiography and its diagnostic accuracy compared with standard echocardiography. METHODS: Two consecutive echocardiographic examinations were performed by experienced and independent examiners using handheld and standard echocardiography. Systolic pulmonary artery pressure was measured by Swan-Ganz catheter. RESULTS: In all, 177 (56.2%) patients had normal cardiac function; 138 (43.8%) had underlying cardiac pathology. Handheld echocardiography had an overall agreement of 94.8% and kappa of 0.89 to detect the main echocardiographic finding. Handheld echocardiography detected valve disease with an agreement of 96.7% and kappa of 0.93; global left ventricular function was assessed correctly in 85.6% of cases. Pericardial effusion was diagnosed with an agreement of 91.2%. Dyssynergy was found by handheld echocardiography with an agreement of 95.4% and kappa value of 0.88. Systolic pulmonary artery pressure measured by handheld echocardiography and Swan-Ganz catheter had a correlation of 0.97. CONCLUSION: This study demonstrates the high diagnostic accuracy of handheld devices with continuous/pulsed wave Doppler and harmonic imaging, and that these devices broaden the diagnostic spectrum while allowing for enhanced mobility in everyday clinical applications.

Apical tissue tracking echocardiography for characterization of regional left ventricular function: comparison with magnetic resonance imaging in patients after myocardial infarction.

OBJECTIVE: The purpose of this study was to characterize the normal pattern of apical tracking and to investigate whether tissue tracking imaging is more useful for evaluation of regional left-ventricular function than noncontrast harmonic echocardiography in patients after myocardial infarction. BACKGROUND: Left ventricular longitudinal shortening plays an important role in cardiac contraction, and can be evaluated online by a new Doppler tissue imaging method. METHODS: We included 40 healthy participants and 40 patients after myocardial infarction. They underwent tissue tracking imaging and noncontrast harmonic imaging by an experienced and an inexperienced observer. Diagnostic accuracy of semiquantitative evaluation of left ventricular function was compared using magnetic resonance imaging as reference method. RESULTS: Velocity-time integrals decreased from basal to apical segments in healthy participants. Tissue tracking imaging has a higher diagnostic sensitivity than noncontrast imaging for the diagnosis of regional wall-motion abnormalities (expert, 78% vs 97%, P <.01; beginner, 63% vs 91%, P <.001), whereas specificity remained unchanged (expert, 99% vs 97%, not significant; beginner, 91% vs 92%, not significant). CONCLUSIONS: Tissue tracking imaging is feasible and evaluates regional systolic myocardial function quantitatively with high diagnostic accuracy compared with magnetic resonance imaging in patients after myocardial infarction, and is more accurate than noncontrast harmonic echocardiography.

Does contrast echocardiography with Optison induce myocardial necrosis in humans?

Myocardial contrast echocardiography is a promising diagnostic tool for detecting microvascular integrity. Multiple experimental laboratories have shown that diagnostic combined microbubble contrast and ultrasound exposure can cause vessel rupture and myocardial damage in laboratory animals. This study investigated the phenomenon of contrast ultrasonically induced myocardial damage in human beings. Twenty consecutive patients (mean age of 60 +/- 12 years, 14 men) underwent contrast echocardiography with intravenous Optison using a mechanical index of at least 1.4 (Vivid Five System (GE, Vingmed Ultrasound, Horton, Norway). Creatine kinase (CK), creatine kinase-isoenzyme MB (CK-MB); CK-MB mass, myoglobin, and troponin I were measured before and 2, 4, 8, and 24 hours after contrast echocardiography. There was no significant correlation concerning the response to contrast echocardiography for any pair of parameters at any time after the intervention. Only in 2 patients were there higher values for troponin I before and after contrast echocardiography without an increase of myoglobin, CK, or CK-MB mass and activity. These values were therefore interpreted as false positive because of renal failure and severe heart failure. The use of contrast echocardiography is without demonstrated risk of myocardial damage even in patients with different cardiologic entities.