Helen Rimington

Long axis excursion in aortic stenosis

OBJECTIVES To examine long axis excursion in patients with all grades of aortic stenosis and preserved transverse systolic function, and to compare long axis excursion in symptomatic with that in asymptomatic severe aortic stenosis. DESIGN Prospective comparative study. SETTING Regional cardiothoracic centre. PATIENTS 78 patients with all grades of aortic stenosis and normal fractional shortening and ejection fraction were studied. There were two comparison groups, 10 age matched normal subjects and 14 patients with aortic stenosis and fractional shortening <u200926%. METHODS Aortic valve function and left ventricular mass were assessed echocardiographically. M mode measurements of long axis excursion at the septal and lateral sides of the mitral annulus were taken. RESULTS There were significant differences between the groups in long axis excursion at both the septal (pu2009<u20090.0001) and lateral sides of the mitral annulus (pu2009=u20090.002 by analysis of variance). Long axis excursion was independently related to both left ventricular mass index (pu2009=u20090.001) and the grade of aortic stenosis (pu2009=u20090.002). Comparing patients with severe aortic stenosis with and without symptoms, there were significant differences in effective orifice area (pu2009=u20090.02 ) and long axis excursion at the lateral side of the mitral annulus (pu2009=u20090.04), but not in fractional shortening, ejection fraction, or peak or mean pressure difference. CONCLUSION In patients with aortic stenosis, long axis excursion is reduced even in the presence of normal fractional shortening or ejection fraction. It is lower in patients with symptomatic compared with asymptomatic severe aortic stenosis and may be of use in predicting the onset of symptoms.

BSE procedure guidelines for the clinical application of stress echocardiography, recommendations for performance and interpretation of stress echocardiography: A report of the British Society of Echocardiography Policy Committee

The British Society of Echocardiography (BSE) procedure guidelines for the clinical application of stress echocardiography, recommendations for performance and interpretation of stress echocardiography are presented here.nnThe objective of guidelines is to enhance appropriateness of practice, improve quality of care, lead to better patient outcomes, and help authorities to decide on the approval of diagnostic or therapeutic procedures. For patients with coronary artery disease (CAD), one of the greatest challenges of our heath care system, a variety of diagnostic procedures is available at varying financial burdens. In order to improve cost effectiveness precise guidelines are needed to advise physicians.1nnStress echocardiography has become a valuable method for cardiovascular stress testing. It plays a crucial role in the initial detection of coronary artery disease, in determining prognosis and in therapeutic decision making.2,3 These recommendations refer to the use of stress echocardiography to assess myocardial ischaemia or viability in patients with coronary artery disease. Evaluation of valvar heart disease or cardiomyopathies is not included but the BSE will provide separate guidelines for these indications in the future.nnStress echocardiography is part of a diagnostic process, which often includes several diagnostic modalities, some of them complementary (for example, stress ECG), others competitive (for example, myocardial scintigraphy or magnetic resonance imaging (MRI)). This is reflected in this document, which outlines the indications and contraindications for stress echocardiography, the recommended methodology, and the clinical use of this technique. This document is intended to supplement other guidelines for cardiovascular stress testing, including the recently published guidelines for myocardial scintigraphy.4,5nnGuidelines have to reflect the specific situation of the local health system and have to be updated to reflect the technical developments of the procedure and the developments of competing procedures. In particular there has been an increasing use of new imaging …

Prediction of symptom-onset in aortic stenosis: a comparison of pressure drop/flow slope and haemodynamic measures at rest☆

To compare the pressure drop/flow slope with peak and mean pressure drop, effective orifice area and aortic valve resistance for the prediction of symptom-onset we performed resting and dobutamine stress echocardiography in 49 asymptomatic patients with aortic stenosis (peak aortic velocity>2.5 m/s). The end-point was progression to symptoms requiring surgery and patients were followed for a mean 21.2 (5.2) months. A total of 23 (47%) patients progressed to symptoms requiring aortic valve replacement and 26 remained asymptomatic. There was no significant difference in age, gender, fractional shortening or the presence or absence of coronary artery disease between these groups. There were differences in peak aortic velocity (P<0.0001), peak and mean pressure drop (P<0.0001), effective orifice area (P=0.03), aortic valve resistance (P=0.001) and pressure drop/flow slope (P<0.0001). On Cox regression analysis, the pressure drop/flow slope (P<0.0001), peak aortic velocity (P=0.005) and peak pressure gradient (P=0.02) were independent predictors. Mean event-free survival at 2 years for peak velocity >4.0 m/s was 17% and for pressure drop/flow slope >0.10 mmHg/ms(-1) was 20%. Of 13 patients reporting symptoms during dobutamine stress, 10 (77%) developed spontaneous symptoms during follow-up compared with 13 of 36 (36%) with no symptoms (P=0.11). The pressure drop/flow slope is a better independent predictor of symptom onset than resistance, mean pressure difference and effective orifice area, but is similar to peak velocity.

The relation between transaortic pressure difference and flow during dobutamine stress echocardiography in patients with aortic stenosis

OBJECTIVE To investigate the relation between transaortic pressure difference and flow in patients with aortic stenosis. METHODS 50 asymptomatic patients with all grades of aortic stenosis were studied using dobutamine stress echocardiography. Individual plots of mean pressure drop against flow were drawn. Comparisons were made between grades of aortic stenosis as defined by the continuity equation. RESULTS A significant linear relation between pressure difference and flow was found in 34 patients (68%). There was a significant curvilinear relation in four (8%), while no significant regression line could be fitted in 12 (24%). In the 34 patients with linear fits, the slopes (mean (SD)) were 0.08 (0.07) in mild, 0.10 (0.04) in moderate, and 0.22 (0.16) in severe aortic stenosis (pu2009=u20090.0055). CONCLUSIONS Transaortic pressure difference can be related directly to flow in many patients with all grades of aortic stenosis. However, there are individual differences in slope and intercept suggesting that resistance calculated at rest may not always be representative. Raw pressure drop/flow plots may be an alternative method of describing valve function.

288 Elevated brain natriuretic peptide is associated with abnormal tissue Doppler characteristics in patients with aortic stenosis

Brain natriuretic peptide (BNP) is expected to be related to left atrial pressure, which can also be estimated using tissue Doppler echocardiography. Aims: To assess the relationship between BNP level and measures el systolic and diastolic function on Tissue Doppler Imaging (Tdi) in patients with aortic stenosis. Methods: We studied 50 patients with asymptomalic moderate to severe aortic slenosis (EOA 100pgml) gave an AUC of 08 for the septal systolic velocity and 0.7 lor the E/E ratio. An E,,E ratio > 10 gave a sensitivity of 76% and specificity 30% for a high BNP while a ratio > 15 gave a sensitivity 67% and specificity 87%. A systolic velocily 15 reliably predict a high BNP level.

A study to examine the interaction between EchoGen and sevoflurane

SummaryThe aims of this study were to investigate possible interactions between EchoGen, a transpulmonary contrast agent in development that vaporizes after injection, and sevoflurane, and to determine the safety of the co-administration of sevoflurane and EchoGen. A phase I, double-blind, randomized, placebo-controlled, three-way crossover study was done in 12 healthy male volunteers receiving: EchoGen alone, sevoflurane+ EchoGen or sevoflurane+saline placebo. Safety was assessed using physiological and haematological monitoring and by documenting adverse events. The mean degree of echocardiography image enhancement was significantly higher for EchoGen alone (78.2) than when combined with sevoflurane (61.2) P=0.036. Both were significantly better than saline placebo (P<0.0001). The mean minimum alveolar concentration of sevoflurane was 2.5% with EchoGen and 2.3% with saline (NS). There were no marked differences in the distribution of reported adverse events between the sevoflurane/EchoGen and sevoflurane/ saline treatments. Results of other safety analyses, including vital signs, laboratory evaluations and physical examinations, were unremarkable. It is concluded that EchoGen with or without administration of sevoflurane significantly enhances echocardiographic image quality compared with saline placebo. However, image quality is significantly better with EchoGen in the absence of sevoflurane. EchoGen does not interfere with the anaesthetic action of sevoflurane. No new safety concerns were identified for either EchoGen or sevoflurane, alone or in combination.