PubMed Health⌕ Search

Biomedical subjects

R P Wilde

Publications and source records attributed to R P Wilde.

8 recordsLinked to original sources
PubMed1993

Limitations of chest radiography in discriminating between aortic dissection and myocardial infarction: implications for thrombolysis.

It has been stated that chest radiographic features of aortic dissection are a contraindication to intravenous thrombolysis in patients with suspected acute myocardial infarction. Excluding aortic dissection could significantly delay such treatment in patients who would benefit from thrombolysis. Initial chest radiographs of 18 patients with acute aortic dissection and 25 patients with acute myocardial infarction were evaluated. The radiographs were studied by two experienced radiologists for signs of aortic dissection. No radiographic signs or combinations of signs accurately distinguished aortic dissection from myocardial infarction. Patients with chest radiographic signs suggesting aortic dissection but with clinical features suggesting myocardial infarction should not be denied the benefits of immediate intravenous thrombolysis.

Aortic Dissection↗
PubMed1990

Aortic valvoplasty: comparison of the techniques and results of transeptal and retrograde methods.

Balloon aortic valvoplasty is used in some patients with aortic valve stenosis who are unsuitable for aortic valve replacement. Complications associated with the retrograde approach can be avoided using an antegrade approach which has been less widely described. Experience of these two methods is reported and aspects of the differences in technique are emphasized. Aortic valvoplasty was attempted in 21 patients with severe aortic valve stenosis (mean gradient 65 mmHg). A significant reduction in gradient was achieved in 20 (mean reduction 59% transeptal group [four patients], 50% retrograde group [16 patients]) with symptomatic improvement in 18 patients which was maintained at follow-up (mean interval of 5.2 months, range 1-17 months) in 8/15 patients. There were only two significant, resolvable early complications and increases in aortic regurgitation were not seen. There were six late deaths but three patients improved sufficiently to undergo successful aortic valve replacement. Aortic valvoplasty provides good palliation of symptoms. In patients who are unsuitable for the retrograde approach the antegrade, transeptal approach is a satisfactory and effective alternative.

Aged↗
PubMed1988

Anomalous origin of the anterior descending coronary artery from a non-dominant right coronary artery.

We present a patient with rheumatic mitral valve disease with anomalous origin of the anterior descending coronary artery. The coronary anatomy was unusual for two reasons; firstly, the anterior descending coronary artery was a branch of a non-dominant right coronary artery, and secondly it passed to the left in the interventricular septum beneath the right ventricular infundibulum. As far as we are aware, this anatomical variation has not been described before and it appears to be of no haemodynamic significance.

Angina Pectoris↗
PubMed1987

Simple anatomical basis for surface electrocardiographic changes during selective coronary arteriography.

The relationship between surface electrocardiographic changes during selective coronary arteriography and coronary artery anatomy was examined in 185 consecutive patients. When both major arteries were patent, two distinct patterns of electrocardiographic changes occurred. Electrocardiogram leads reflecting the areas supplied by the injected vessels showed a change we have termed the 'perfusion response', while electrocardiogram leads reflecting regions not supplied by the injected vessel simultaneously showed a pattern we have termed the 'reciprocal response'. These changes were reproducible on serial injections, and occurred whether or not coronary artery or valvular heart disease was present. A third type of electrocardiographic change--termed a 'biphasic response' and comprising a reciprocal followed by a perfusion response--was observed in leads reflecting a collateral-dependent region of viable myocardium. This response was seen in the inferior surface leads with left coronary artery injection when the right coronary artery was occluded, but not in leads I and aVL with right coronary artery injection when a branch of the left coronary artery was occluded, where chest leads may be needed for its detection. The biphasic response was also seen in the inferior leads with left coronary artery injection in patients in whom this artery was dominant. Thus, the distribution of electrocardiographic changes during arteriography is dependent on native coronary artery anatomy, collateral vessels and myocardial viability. Changes relate to the site of coronary lesions only where vessels are occluded, but may be of practical value when the viability of (and thus suitability for bypass grafting to) a myocardial region is in doubt.

Contrast Media↗
PubMed1986

Dipyridamole combined with exercise for thallium-201 myocardial imaging.

A new stress test for thallium-201 myocardial imaging in which pharmacological coronary vasodilatation with dipyridamole is combined with dynamic exercise is described. In 38 patients with coronary artery disease the sensitivity, total number of defects, degree of redistribution, and visual quality of thallium-201 imaging were greater after dipyridamole with exercise testing than after exercise alone. When the data from these 38 patients were combined with the results of dipyridamole-exercise imaging in 49 patients in whom exercise electrocardiography had been inconclusive then the technique gave a sensitivity for coronary disease of 87% and a specificity of 92%. Dipyridamole also increased the sensitivity of the exercise electrocardiogram, so that no patient with coronary disease had a strictly negative dipyridamole-exercise stress test. Only five of 214 patients who have now undergone this test have had complications requiring reversal of vasodilatation with aminophylline. The combined use of dipyridamole and exercise in this simple technique is a reliable and safe improvement on standard thallium-201 imaging tests.

Adult↗
PubMed1984

The potential of phase and amplitude images in determining the boundary of the left ventricle.

The phase and amplitude images derived from multiple gated blood pool studies of the heart have been used to aid the delineation of the boundary of the left ventricle. The results of left ventricular ejection fraction (LVEF) using this method have been compared with those obtained using edge detection algorithms, dual region of interest techniques, and x-ray contrast ventriculography, in a series of patients with well documented left ventricular wall motion. The results indicate that the sole use of phase and amplitude images does not improve the correlation or accuracy of LVEF estimation in relation to those obtained by x-ray contrast ventriculography, and that the dual region of interest technique is likely to remain the preferred method.

Adult↗