Role of real time 3D echocardiography in evaluating the left ventricle.
Explore the source record for details and available documents.
Echocardiography, Three-Dimensional↗
Biomedical subjects
Mark J Monaghan
Publications and source records attributed to Mark J Monaghan.
Cardiac resynchronization therapy: Part 1--issues before device implantation.
Cardiac resynchronization therapy (CRT) has been used extensively over the last years in the therapeutic management of patients with end-stage heart failure. Data from 4,017 patients have been published in eight large, randomized trials on CRT. Improvement in clinical end points (symptoms, exercise capacity, quality of life) and echocardiographic end points (systolic function, left ventricular size, mitral regurgitation) have been reported after CRT, with a reduction in hospitalizations for decompensated heart failure and an improvement in survival. However, individual results vary, and 20% to 30% of patients do not respond to CRT. At present, the selection criteria include severe heart failure (New York Heart Association functional class III or IV), left ventricular ejection fraction <35%, and wide QRS complex (>120 ms). Assessment of inter- and particularly intraventricular dyssynchrony as provided by echocardiography (predominantly tissue Doppler imaging techniques) may allow improved identification of potential responders to CRT. In this review a summary of the clinical and echocardiographic results of the large, randomized trials is provided, followed by an extensive overview on the currently available echocardiographic techniques for assessment of LV dyssynchrony. In addition, the value of LV scar tissue and venous anatomy for the selection of potential candidates for CRT are discussed.
Cardiac Output, Low↗
Cardiac resynchronization therapy: Part 2--issues during and after device implantation and unresolved questions.
Encouraged by the clinical success of cardiac resynchronization therapy (CRT), the implantation rate has increased exponentially, although several limitations and unresolved issues of CRT have been identified. This review concerns issues that are encountered during implantation of CRT devices, including the role of electroanatomical mapping, whether CRT implantation should be accompanied by simultaneous atrioventricular nodal ablation in patients with atrial fibrillation, procedural complications, and when to consider surgical left ventricular lead positioning. Furthermore, (echocardiographic) CRT optimization and assessment of CRT benefits after implantation are highlighted. Also, controversial issues such as the potential value of CRT in patients with mild heart failure or narrow QRS complex are addressed. Finally, open questions concerning when to combine CRT with implantable cardioverter-defibrillator therapy and the cost-effectiveness of CRT are discussed.
Atrial Fibrillation↗
Tissue harmonic imaging for standard left ventricular measurements: fundamentally flawed?
Tissue harmonic imaging (THI) is a B mode imaging technique that improves echocardiographic image quality by reducing superficial artefact. The modality increases image signal-to-noise ratio at the expense of reduced axial resolution. While the qualitative improvements of harmonic echocardiographic imaging are widely accepted, the degree to which this is translated into improved quantitative measurements and whether THI-derived measurements result in systematic bias continue to be areas of uncertainty. This review examines differences between THI and fundamental imaging-derived measurements from a theoretical, tissue phantom and clinical perspective.
Echocardiography↗
Normal values of left ventricular systolic and diastolic function derived from signal-averaged acoustic quantification waveforms: a multicenter study.
Automated border-detection techniques such as acoustic quantification have proven accurate and useful for quantifying left ventricular (LV) function. We acquired LV acoustic quantification waveforms from the parasternal short-axis window in 140 healthy patients in the age range of 16 to 78 years. Signal-averaged waveforms were analyzed for parameters of systolic and diastolic performance. The average fractional area change was 54 +/- 12%, and there were no significant changes in LV systolic function in the age range studied. There were significant changes in diastolic parameters with aging. The percentage of contribution to total LV filling occurring during atrial filling nearly tripled during the 6 decades studied, from 13% in the youngest cohort to 36% in the eighth decade of life. This study provides normal reference values for systolic and diastolic parameters of LV function determined from signal-averaged acoustic quantification waveforms acquired from the parasternal short-axis view in adult and adolescent patients over a wide age range.
Adolescent↗
Interpretation of plasma brain natriuretic peptide concentrations may require adjustment for patient's age.
BACKGROUND: Brain natriuretic peptide (BNP) is increasingly recognized as a practical, reliable and accurate indicator of left ventricular function and may have an important prognostic role in determining outcome following myocardial infarction and heart failure. METHODS AND RESULTS: We studied a total of 60 patients referred for dobutamine-stress echocardiography to evaluate possible reversible myocardial ischaemia. There was no echocardiographic evidence of structural or functional heart disease in any of the patients included in the study. Blood was sampled for BNP at rest, prior to dobutamine-stress. We found a significant linear correlation between BNP concentrations and patients' age, in the absence of structural or functional heart disease (r(s) = 0.53, 95% CI 0.25-0.73, P<0.0001). CONCLUSION: Our observations suggest the need for consideration of patient's age when interpreting BNP concentrations in the population.
Adult↗