PubMed Health⌕ Search

Biomedical subjects

M B Mishra

Publications and source records attributed to M B Mishra.

6 recordsLinked to original sources

A comparison of wall motion analysis and systolic left ventricular long axis function during dobutamine stress echocardiography.

AIMS: To compare long-axis function and wall motion analysis for the detection of significant coronary artery stenoses in patients with single and multivessel disease. METHODS AND RESULTS: We performed dobutamine stress echocardiography in 67 subjects, 14 with normal coronary anatomy, and 53 with significant coronary disease. A blunted increase in mean long-axis shortening of <0.25 cm was the best discriminator for coronary artery disease (sensitivity 85%, specificity 81%). Using this threshold, long axis function gave a sensitivity of 88% and specificity 89% for the detection of coronary artery disease in patients with normal resting wall motion while wall motion abnormality analysis had a sensitivity 73% and specificity 94%. Of 26 patients with a resting wall motion abnormality, 14 (54%) had multivessel disease. Long axis function detected multivessel disease in 12 of these (sensitivity 86%) compared with nine (sensitivity 64%) for wall motion analysis. CONCLUSION: Long axis function provides a promising, quantitative adjunct to wall motion analysis for the detection of coronary ischaemia using dobutamine stress echocardiography in patients with single and multivessel disease and with resting wall motion abnormalities.

Adult↗

Haemodynamic changes during dobutamine stress echocardiography in patients with and without ischaemia.

We studied haemodynamic changes during dobutamine stress echocardiography in 69 patients (mean age 58 years, 6 female, 63 male) referred for investigation of chest pain. We used a standard protocol of 3 min stages using infusion rates of 5, 10, 20, 30 and 40 micrograms/kg/min. Heart rate rose from 74 (13) to 123 (21) beats per min with the major increment occurring during the high dose phase of the study (> 20 micrograms/kg/min). Stroke volume was calculated as the product of left ventricular outflow tract cross-sectional area and the velocity integral of the continuous wave aortic signal. Mean stroke volume increased from 67.5 (22) ml pre-test to 82 (22) ml at 20 micrograms/kg/min dose (P < 0.0001) and 85 (21) ml at 40 micrograms/kg/min (P < 0.00001). Only 15 patients (26%) reached their maximal stroke volume by 10 micrograms/kg/min, 38 patients (65%) reached maximal stroke volume by 20 micrograms/kg/min. Patients with ischaemic responses tended to have a blunted rise in stroke volume from 67 (22) ml to 85 (22) ml at maximum compared with a rise from 69 (23) to 92 (19) ml in those without ischaemic (P = 0.09). In conclusion, the early rise in cardiac output during dobutamine stress was mainly due to a rise in stroke volume and the later due to an increase in heart rate. Individual increases in stroke volume did not adequately differentiate between ischaemic and non-ischaemic results.

Adult↗

Clinical and echocardiographic survey of the Ehlers-Danlos syndrome.

Cardiac abnormalities such as mitral valve prolapse (MVP) are reported to be common features of the Ehlers Danlos syndrome (EDS), and it has been suggested that the majority of patients with type IV EDS will have cardiac involvement and vascular aneurysms. However, the evidence for valve lesions is inconsistent and often based on early clinical studies using mainly M-mode echo. We studied 33 patients (six male, 27 female; median age 35 yr) with EDS (30 type I, II or III, three type IV) and 30 age- and sex-matched controls. The study assessed skin stretch and joint hypermobility using Beighton and Contompasis scores. Echocardiographic examination included standard two-dimensional views from the parasternal and apical windows, and measurement of the aorta at four sites (annulus, sinotubular junction, arch and abdominal aorta). Echocardiographic abnormalities were found in four patients (12.1%) (one atrial septal aneurysm, one tricuspid prolapse, two MVP) and two controls (6.7%). MVP was found in 6.1% of EDS patients and 7% of controls. Seven patients had previously been diagnosed as having MVP; only two were shown to have true MVP using current criteria. None of those with type IV EDS had any echocardiographic abnormality. No patients with EDS had mean aortic dimensions outside the normal range at any of the points tested. Cardiac symptoms were more frequent amongst the patients than controls (atypical chest pain 48%, P = 0.0001; palpitation 39%, P = 0.001; exertional dyspnoea 30%). A wide range of rheumatological complaints were reported (current arthralgia 75%; recent back pain 72%, P = 0.005; recurrent dislocation 72%). Contrary to earlier published observations, we have not found an increased incidence of cardiac abnormalities in EDS. This syndrome may be relatively more benign, from the cardiac point of view, than was previously thought.

Adolescent↗

Extra-articular features of benign joint hypermobility syndrome.

To define the phenotype of patients with benign joint hypermobility syndrome (BJHS), we studied 58 consecutive patients (mean age 37 yr) presenting to a rheumatology clinic and 30 controls. Patients underwent rheumatological and ophthalmic examination, hypermobility scoring, echocardiography, measurement of bone mineral density (BMD), and skin thickness, elasticity and light transmissibility. The median hypermobility score was 5/9 Beighton and 31/56 Contompasis. Eighteen (31%) patients complained of significant arthralgia. Six (10%) patients and two (7%) controls had mitral valve prolapse (MVP) (chi(2) = 0.27, P = NS). Neither MVP nor aortic diameters showed a correlation with hypermobility score. There was no significant reduction in BMD. There was a significant correlation between hypermobility and light transmissibility of the skin (r = 0.71, P < 0.0001 Contompasis; r = 0.47, P < 0.05 Beighton) and skin stretchiness (r = 0.49, P < 0.05 Contompasis; r = 0.39, P < 0.05 Beighton). On ophthalmic examination, 14 (41%) patients had upper eyelid laxity. Thus, patients with BJHS do not have an increased prevalence of significant cardiac, bone, skin or eye abnormalities, helping differentiate BJHS from other more serious hereditary disorders of connective tissue.

Adolescent↗

Stress echocardiography.

Stress echocardiography has a number of advantages over exercise electrocardiography. It has superior sensitivity and specificity as it detects wall motion abnormalities, an earlier and more specific marker for myocardial ischaemia than ST segment depression. It can also localise ischaemia and identify hibernating myocardium. Compared with radionuclide imaging, stress echocardiography has similar accuracy but is cheaper and does not involve exposure to ionising radiation. The disadvantage of stress echocardiograph is that it requires expertise and specialist experience of at least 100 studies. Current research aims at improving objective methods of analysing results. The technique is justifiably being adopted throughout the UK.

Cardiovascular Agents↗