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N Bett

Publications and source records attributed to N Bett.

17 recordsLinked to original sources
PubMed2005

Distribution of mesorectal lymph nodes in rectal cancer: in vivo MR imaging compared with histopathological examination. Initial observations.

The aim of this work was to determine the distribution of mesorectal lymph nodes using T2-weighted magnetic resonance (MR) imaging compared with histopathological findings in patients with rectal carcinoma. Sixteen patients with rectal carcinoma undergoing primary surgery without pre-operative neoadjuvant treatment were evaluated using 3-mm axial T2-weighted MR imaging. The position of each visible mesorectal node on imaging was localised by measuring its minimum distance from the mesorectal fascia (d(m)), its minimum distance from the rectal wall (d(r)) and its distance from the distal tumour margin (d(v)). Independent assessment of d(m), d(r) and d(v) was made at histopathological examination. Eighty-five mesorectal nodes on in vivo MR imaging were matched to histopathological findings. On imaging, 67/85 mesorectal nodes were found at the level of the tumour and 84/85 were identified at or within 5 cm proximal to the tumour. Only one out of 85 nodes was seen below the inferior tumour margin. The mean difference of d(m) and d(r) obtained on in vivo MR imaging and histopathological examination was 0.7 mm (95% confidence interval, CI, -0.12 to 1.42 mm) and -1.1 mm (95% CI -2.29 to 0.14 mm), respectively. Almost all mesorectal nodes visible on MR imaging were found at the level of tumour or within 5 cm proximal to the tumour. This has implications for the planning of MR imaging and the level of mesorectal transection at surgery.

Adenocarcinoma↗
PubMed1999

Lack of effect of coenzyme Q on left ventricular function in patients with congestive heart failure.

OBJECTIVES: This study evaluated the effects of oral therapy with coenzyme Q on echocardiographic and hemodynamic indexes of left ventricular function and on quality of life in patients with chronic left ventricular dysfunction. BACKGROUND: Coenzyme Q is a coenzyme for oxidative phosphorylation and an antioxidant and free radical scavenger. It has been claimed to improve symptoms, quality of life, left ventricular ejection fraction and prognosis in patients with cardiac failure. METHODS: Thirty patients with ischemic or idiopathic dilated cardiomyopathy and chronic left ventricular dysfunction (ejection fraction 26 +/- 6%) were randomized to a double-blind crossover trial of oral coenzyme Q versus placebo, each for 3 months. Right heart pressures, cardiac output and echocardiographic left ventricular volumes were measured at baseline and after each treatment phase, and quality of life was assessed using the Minnesota "Living With Heart Failure" questionnaire. It was calculated that to demonstrate an increase in left ventricular ejection fraction from 25% to 30% with a standard deviation of 5% using 95% confidence intervals with a power of 80% we would require 17 patients. RESULTS: Twenty-seven completed both treatment phases. There was no significant difference in left ventricular ejection fraction, cardiac volumes or hemodynamic and quality of life indices after treatment with coenzyme Q or placebo, although plasma coenzyme Q levels increased from 903 +/- 345 nmol/l(-1) to 2,029 +/- 856 nmol/l(-1). CONCLUSIONS: In patients with left ventricular dysfunction, treatment for three months with oral coenzyme Q failed to improve resting left ventricular systolic function or quality of life despite an increase in plasma levels of coenzyme Q to more than twice basal values.

Administration, Oral↗
PubMed1995

Directional coronary atherectomy for lesions of the proximal left anterior descending artery: initial clinical results, complications and histopathological findings.

BACKGROUND: Directional coronary atherectomy is a percutaneous technique which extends the role of balloon angioplasty to bulky eccentric coronary lesions. AIMS: To report the early experience, clinical results, complications and histopathological findings of directional coronary atherectomy (DCA) in proximal left anterior descending artery (LAD) stenosis. METHODS: Study of 25 lesions in 24 patients on whom directional atherectomy was performed on the proximal LAD artery with the Simpson coronary atherectomy device. RESULTS: Twenty-five procedures were performed on 24 patients with stenosis in the proximal LAD artery. There were 21 males and three females with a mean age of 56.5 years. Sixteen patients presented with stable angina and eight with unstable angina. Eight patients had previous myocardial infarction (MI). Angiographic success was obtained in 24 of 25 lesions (96%). The mean lesion length was 13.1 +/- 3.7 mm and the mean LAD artery diameter was 3.6 +/- 0.5 mm. Minimal luminal diameter improved from 0.9 +/- 0.4 mm to 3.0 +/- 0.5 mm and the percentage diameter stenosis reduced from 75 +/- 12% to 16 +/- 9%. Complications included acute occlusion in one patient, non-Q MI in three patients, local vascular complications in one patient and side-branch loss in one patient. Histology demonstrated fibrous cap of atherosclerotic plaque in 100%, media and internal elastic lamina in 28% and intimal hyperplasia in 100% of restenotic lesions and 27% of native lesions. Restenosis rates in angiographically restudied patients was 27%. The mean minimal luminal diameter at follow-up was 2.3 +/- 0.9 mm and the mean percentage diameter stenosis was 35 +/- 21%. CONCLUSION: From this initial study, we conclude that DCA is an effective and safe procedure for the treatment of large proximal LAD lesions. DCA provides a large luminal diameter and "smoother' angiographic appearance compared to coronary angioplasty. Acute complication rates are low and restenosis rates were comparable with percutaneous transluminal coronary balloon angioplasty.

Adult↗
PubMed1994

Outcome five years after percutaneous transluminal coronary angioplasty or coronary artery bypass grafting for significant narrowing limited to the left anterior descending coronary artery.

Percutaneous transluminal coronary angioplasty (PTCA) and coronary artery bypass grafting (CABG) are both used widely for angina but information about their comparative efficacy is limited. This study compared the outcome of 358 consecutive patients undergoing initial revascularization for significant narrowing of the left anterior descending artery (LAD) by PTCA (n = 254) or CABG (n = 104) from 1987 to 1989. PTCA was successful in 93% but complicated by urgent CABG in 3%. A left internal mammary graft was used in 88% of those having elective CABG. There was 1 perioperative death. Follow-up data were obtained after a median interval of 5.5 years (maximum 7.1). Rates for freedom from death (97% PTCA vs 93% CABG, p = 0.06) were similar, but CABG patients had greater rates for freedom from chest pain recurrence (74% CABG vs 48% PTCA, p < 0.0001), myocardial infarction (98% vs 92%, p = 0.04), and from need for further revascularization (99% vs 67%, p < 0.0001). Both groups achieved similar status, with 81% of PTCA and 90% of CABG patients having angina no worse than functional class I. Quality-of-life index was high for both groups (0.983 +/- 0.034/1.000 vs 0.987 +/- 0.032/1.000, p = 0.3). Both PTCA and CABG result in excellent survival, functional ability, and quality of life, but patients undergoing PTCA require more procedures to achieve this.

Adult↗
PubMed1994

Experience with the Gianturco-Roubin stent for abrupt vessel closure complicating percutaneous transluminal coronary angioplasty.

BACKGROUND: Emergency coronary artery bypass grafting (CABG) has previously been the only option in the treatment of refractory abrupt vessel closure complicating percutaneous transluminal coronary angioplasty (PTCA), and has been associated with high rates of morbidity and mortality. Intracoronary stenting now provides an alternative to emergency CABG. AIM: To assess our initial experience with emergency coronary artery stenting as a new technique. METHODS: Retrospective case study review with clinical and angiographic follow-up. RESULTS: The Gianturco-Roubin (GR) stent was deployed in 13 patients in whom PTCA was complicated by abrupt vessel closure refractory to standard balloon techniques. Indications for PTCA were unstable angina (six), stable angina (six) and acute myocardial infarction (MI) (one). The arteries stented included left anterior descending (LAD) artery lesions (eight) and right coronary artery lesions (five). Two patients required urgent CABG, one due to failed stent deployment and one for inadequate control of vessel dissection. In seven of the stented patients the creatine kinase rose to greater than twice the upper limit or normal. Three patients had subacute thrombotic occlusion at seven to 19 days post stent deployment, managed with intravenous thrombolysis or repeat PTCA. At seven months follow-up, 11 patients were free of angina, two patients had Canadian Heart Association class II angina and there were no deaths. Eleven patients had repeat angiography at mean six months post stent. Five patients had evidence of restenosis managed with repeat PTCA in four and CABG in one. CONCLUSIONS: The GR stent is an effective alternative to urgent CABG in the treatment of refractory abrupt vessel closure complicating PTCA.

Angioplasty, Balloon, Coronary↗
PubMed1993

Impact of a national educational campaign to reduce patient delay in possible heart attack.

In 1989 the National Heart Foundation (NHF) of Australia's Heart Week campaign was directed towards encouraging those with symptoms of possible myocardial infarction (MI) to seek help as promptly as possible. To evaluate its effect, three surveys were conducted of patients admitted to 22 coronary care units (CCUs). Two (335 and 221 patients) preceded and one (253 patients) followed the public education campaign. During the third survey a subset of patients were asked why they delayed, how long they thought one should wait before seeking help, whether they were aware of the media campaign and whether this had influenced their behaviour. Overall, only 42% of 809 patients sought help within one hour (median delay 1.2 hours). The median time of arrival and the proportion of patients arriving within one, two and four hours was not altered after this campaign. Those who admitted to having been aware of the campaign sought help no more promptly. The Heart Week campaign could not be shown to have produced any clinically important change in patient delay. Future campaigns will need to be modified in the light of this experience.

Female↗
PubMed1988

Familial restrictive cardiomyopathy.

The cases of a father and daughter with idiopathic restrictive cardiomyopathy are described. In contrast to other forms of cardiomyopathy, this type is rarely familial.

Adult↗
PubMed1986

Hemodynamic properties of bucindolol, a beta-adrenoreceptor blocking drug with vasodilator activity.

Bucindolol is a new nonselective beta-adrenergic blocking agent with direct vasodilator, partial agonist and alpha-adrenergic blocking properties. Its hemodynamic effects were evaluated in 13 healthy young men. In an open study, the effects of increasing single oral doses (50 to 200 mg) were examined. Two hours after each dose there was little effect at rest, but the responses of heart rate and systolic blood pressure to cycle exercise (50 to 150 W) were significantly reduced. There was no greater effect with larger doses. The second phase was a 3-way double-blind study comparing the effects of placebo with 50 and 200 mg of bucindolol. Left ventricular (LV) ejection phase indexes derived from digitized M-mode echocardiograms (% fractional shortening, mean and peak velocity of circumferential fiber shortening, stroke volume) increased more than 10% 2 and 4 hours after bucindolol was administered, whereas systemic vascular resistance and the ratio preejection period/LV ejection time decreased to the same extent. Although there was little effect on measurements at rest, the response to cycle exercise of heart rate and systolic blood pressure were significantly attenuated. These results show that the effects of bucindolol on LV systolic function are related at least in part to reduction of afterload, but do not indicate whether the drug has an additional direct inotropic effect.

Adrenergic beta-Antagonists↗
PubMed1986

Peripartum cardiomyopathy: echocardiographic features in five cases.

Five cases of peripartum cardiomyopathy are presented. All patients were aged less than 35 years, and four were multiparous. Two cases followed twin deliveries. Pulmonary embolism was diagnosed in four patients. Electrocardiograms showed left ventricular hypertrophy or left bundle branch block. On echocardiography, left ventricular minor axis dimensions were increased (diastolic, 67 +/- 7 mm; systolic, 59 +/- 7 mm) and mean fractional shortening was reduced (13% +/- 5%). All patients had hypokinesis or akinesis of the left ventricular segments and two had right ventricular dilatation. Gallium scanning performed in three patients was negative. Viral serologic testing was negative in all cases. All patients died within 5 years, three within 5 months. Survival duration was closely correlated with left ventricular fractional shortening. Autopsy in three patients confirmed the diagnosis of a dilated cardiomyopathy.

Adult↗
PubMed1980

Minoxidil and labetalol: very effective antihypertensive combination.

Minoxidil is an extremely potent hypotensive drug. Good control of refractory hypertension can be achieved without major side effects by using small to moderate doses in combination with other drugs. In particular, minoxidil and labetalol are effective when they are used with frusemide.

Adult↗