Search PubMed⌕ Search

Biomedical subjects

H Forrest

Publications and source records attributed to H Forrest.

At least 19 recordsLinked to original sources
PubMed1986

Arterio-venous shunting complicating occlusive atherosclerotic peripheral vascular disease.

Three cases of severe occlusive peripheral vascular disease are described in which spontaneous arterio-venous fistulae at the site of atheromatous occlusion have been demonstrated by angiography during the arterial phase. Although none of these patients exhibited specific clinical signs of an arterio-venous fistula, this phenomenon is considered to have been a clinically significant factor in the patients' peripheral ischaemia. In one case both the superficial femoral artery stenosis and the spontaneous shunts were effectively treated by percutaneous angioplasty.

Aged↗
PubMed1984

Pulsed Doppler imaging and spectrum analysis for detection of carotid artery disease.

One hundred carotid arteries in 53 patients suffering from transient cerebral ischaemia or amaurosis fugax have been studied prospectively. Internal carotid arteries were assessed by a six-channel pulsed Doppler imaging system combined with Doppler spectrum analysis and the findings compared with those obtained by X-ray contrast arteriography. Stenosis (greater than 25% diameter reduction) was correctly diagnosed by ultrasonography with a sensitivity of 93% and a specificity of 96%. Occlusion was correctly diagnosed with a sensitivity of 92% and a specificity of 97%. The ability to recognize arterial stenosis and occlusion with this noninvasive system suggests that it has a major part to play in screening patients with suspected carotid artery disease.

Adult↗
PubMed1983

Pressure contour analysis in the assessment of arterial stenosis.

Femoral artery pressure contour can be measured directly by percutaneous needle puncture and may be a useful indicator of proximal vessel stenosis. Pressure waveform in 53 limbs was compared with radiological appearance of the aorto-iliac segment. Forty-one limbs were graded angiographically as normal and 12 as stenosed. Pressure contour was studied at rest and after intra-arterial injection of papaverine. The following parameters were examined: 1. systolic pressure at rest 2. systolic pressure after papaverine 3. per cent reduction of systolic pressure after papaverine 4. pulse pressure at rest 5. pulse pressure after papaverine 6. per cent reduction in pulse pressure after papaverine 7. maximal gradient (dp/dt) at rest 8. maximal gradient after papaverine: p less than 0.001 (Figure 5b) 9. (formula; see text) A significant difference between the angiographic normal and stenotic groups was found in the values of all parameters. p less than 0.001 for 1 to 8 inclusive; p less than 0.05 for 9. Good discrimination between groups was achieved only by 3, 6 and 8. Three produced the best discrimination: systolic pressure reduction after papaverine greater than or equal to 14 per cent indicating stenosis (1 in 12 false negative) and less than 14 per cent indicating no stenosis (no false positive).

Adult↗
PubMed1983

Pulsed Doppler imaging for carotid artery disease.

Ultrasonic imaging using a six-channel pulsed Doppler system combined with Doppler spectral analysis of 65 carotid bifurcations has been studied in a prospective clinical trial. The results were compared with X-ray contrast angiography. An overall sensitivity in excess of 90 per cent was achieved using the ultrasound technique, with a specificity of 89 per cent in the detection of significant stenosis or occlusion of the internal carotid artery. The ability to recognise significant arterial stenosis with a non-invasive system suggests that it has a major part to play in screening patients with suspected carotid artery disease.

Aged↗
PubMed1983

The decision on surgery in renal artery stenosis.

Eighty-six hypertensive patients with arteriographic evidence of renal artery stenosis presented between 1968 and 1979. Thirty-nine subsequently underwent surgery and were followed thereafter for at least one year. In 54 per cent blood pressure was reduced to within one standard deviation of the mean for a normal individual of the same sex and age. A further thirty-one per cent of patients were 'improved', but needed hypotensive drugs to maintain blood pressure within this range. In the remaining 15 per cent of patients the operation did not reduce blood pressure. The purpose of the study was to assess our ability to predict this varies surgical outcome using clinical observations and special tests. The latter included measurement of plasma renin concentration in both peripheral vein and renal vein plasma, catheterization of both ureters and studies of the response of blood pressure to brief infusion of saralasin. No single observation or test, no combination of observations or tests and no discriminant function clearly separated patients in whom surgery would succeed from those in whom it would fail. Renal vein renin ratio was the best test; all patients with a ratio greater than 2.0 underwent successful surgery, but so too did some patients with a lower ratio. We also analysed the factors which had influenced our decision to undertake special investigations in 65 of the 86 patients and, having done these investigations, to recommend surgery in 39. No single factor seemed to have had overriding importance in making these decisions.

Adolescent↗
PubMed1981

Haemodynamic assessment following iliac artery dilatation.

Fourteen patients with symptomatic atheromatous stenoses of common or external iliac arteries underwent percutaneous arterial dilatation. Twelve procedures were considered successful in terms of arteriographic and symptomatic improvement but the application of three haemodynamic indices (pressure index, pulsatility index and the papavarine test) indicated that only 8 patients had gained a significant improvement in blood flow. These results illustrate the need for quantitative measurements in the assessment of this new technique.

Angioplasty, Balloon↗
PubMed1976

Thermography in lower limb arterial disease.

Skin temperature distributions are described which correspond to different levels of arterial obstruction in the lower limbs. These temperature distributions are conveniently observed using thermography. Thermography may be used to measure the change in skin temperature when the limb performs work. These skin temperature changes have been correlated with the impairment of blood flow to the lower limb.

Adult↗