Search PubMed⌕ Search

Biomedical subjects

P Block

Publications and source records attributed to P Block.

At least 19 recordsLinked to original sources
PubMed2006

Smoking rates and smoking cessation among individuals with multiple sclerosis.

PURPOSE: Adults with physical disabilities tend to smoke at higher rates than smokers in the general population. No study to date, however, has assessed smoking prevalence and cessation among individuals with multiple sclerosis (MS). Such information is critically needed because smoking is more deleterious for individuals with MS than for smokers without MS and increases MS risk. METHOD: Questionnaires were sent to 700 National Multiple Sclerosis Society Rhode Island Chapter members. RESULTS: Based on a 50% response rate, results demonstrated a 15.2% current smoker prevalence rate, which is lower than USA and Rhode Island general adult population averages. Individuals who smoked, however, tended to be heavy smokers, consuming 20 - 30 cigarettes daily, and had been smoking 10 years or longer. Smokers varied in their interest in quitting but seemed confident in their ability to do so. Respondents reported that it was difficult to quit because smoking was pleasurable; smoking was helpful in coping with boredom and with having MS; withdrawal symptoms were unpleasant; and treatment for tobacco dependence was expensive. CONCLUSIONS: Efficacious smoking cessation interventions for smokers with MS should be developed to address a critical health need for a population of highly nicotine-dependent smokers who face numerous obstacles to quitting.

Chi-Square Distribution↗
PubMed2004

Association between leisure time physical activity and markers of chronic inflammation related to coronary heart disease.

BACKGROUND: Some markers of chronic inflammation have been recognized as predictors of cardiovascular risk in apparently healthy subjects and in patients with coronary heart disease (CHD). High sensitivity C-reactive protein (CRP) appears to be the most useful marker in clinical settings. Several studies reported associations between inflammatory markers and other cardiovascular risk factors, such as age, obesity, cholesterol levels, the presence of diabetes mellitus, physical activity, social level and smoking habits. We focussed on the association between C-reactive protein, serum amyloid A (SAA), fibrinogen and leisure time physical activity (LTPA). METHODS: This report deals with the results observed in a sub-sample of the BELSTRESS study. 892 male subjects, free from clinical CHD and major ECG abnormalities, working in the same environment, aged 35-59 years, were selected. A questionnaire was used to estimate the level of leisure time physical activity. Associations between CRP, SAA, fibrinogen and leisure time physical activity were evaluated through univariate and multivariate methods. Subjects taking statins or other lipid lowering medication were excluded from the study. RESULTS: Regular leisure time physical activity is associated with reductions of several cardiovascular risk factors, such as body mass index (BMI), waist hip ratio and the lipid profile. Smokers and low educated subjects had a lower physical activity status. Age adjustment did not alter the means of inflammatory parameters according to the levels of leisure time physical activity. After correction for personal characteristics (BMI, current smoking status, educational level, presence of diabetes and alcohol consumption) no significant relation was found between leisure time physical activity and levels of inflammatory markers. The differences of CRP and fibrinogen according to the level of physical activity, found in bivariate analysis, seem to be explained by linked differences in BMI, or related to current smoking habits. Leisure time physical activity, as reported in this study, is not significantly related to C-reactive protein, serum amyloid A or fibrinogen levels, after correction for other cardiovascular risk factors. CONCLUSION: These data indicate that leisure time physical activity, as reported in our study, is not an independent predictor of C-reactive protein, serum amyloid A or fibrinogen levels. Possible interactions of physical activity and other cardiovascular risk factors might explain the (indirect) relation we found in the bivariate analysis.

Adult↗
PubMed2004

Primary prevention of coronary heart disease in general practice: a cross sectional population study.

The aim of this study was to assess the interventions by general practitioners on cardiovascular risk factors among persons without a history of cardiovascular disease attending for a cardiovascular check-up. All inhabitants of three Belgian towns aged between 45 and 64 years were invited for a cardiovascular check-up and blood test. Of all the attending persons without a history of cardiovascular disease (n = 898), 51% received at least one prescription, diet or health advice: 28% for hyperlipidaemia, 23% for physical activity, 22% for caloric intake, 9% for blood sugar, 5% for blood pressure and 4% for smoking. Interventions on lipoproteins, blood sugar and smoking habits were significantly more often proposed to persons with a medium or high cardiovascular risk compared to those at low cardiovascular risk. For persons at low cardiovascular risk, therapeutic lifestyle changes are often not advised, and isolated risk factors often remain untreated.

Blood Glucose↗
PubMed2000

Manpower in cardiology in Europe. The Cardiology Monospeciality Section of the UEMS.

This is the first systematic survey of cardiology manpower in Europe. Hitherto, there has been no published information on the number of cardiologists in the different European nations and whether it was growing or stable. Important differences in the number of cardiologists and trainees are observed, with the highest figures in Greece, Italy and France (more than 80/10(6)inhabitants) and the lowest in the Scandinavian nations, Austria, Germany and the U.K. (35 or less/10(6)inhabitants). This is partly due to different roles and the activities of the cardiologists in these countries as well as their capacity to undertake various cardiological procedures. Some comparisons with the U.S.A. and projections for the year 2000 are also made.

Cardiology↗
PubMed2000

Impact of second harmonic imaging on the determination of the global and regional left ventricular function by 2D echocardiography: a comparison with MIBI gated SPECT.

AIMS: To evaluate the impact of second harmonic (SH) compared to fundamental mode (FM) imaging on the echocardiographic determination of ejection fraction (EF) and wall motion score index (WMSI), using MIBI gated SPECT as an independent reference. METHODS: Sixty-two consecutive patients underwent an echocardiography study and a MIBI gated SPECT over 24 hours. EF was estimated visually (estimated-E) and was calculated with the Simpson biplane method (Tracing-T), for both FM and SH. WMSI was determined by two independent echo-readers blinded to the nuclear imaging results. The same segmentation and scoring system was used for WMSI determined by MIBI gated SPECT. RESULTS: The percentages of unscored segments because of suboptimal endocardial border detection were 19.5% (FM) and 9.0% (SH). The correlation coefficients (r) between SPECT-EF and echo-EF were: FM (E)=0.705, FM (T)=0.546, SH (E)=0.771, SH (T)=0.743. Agreement between SPECT-EF and echo-EF was acceptable for both imaging modalities (mean of the difference +/- 2 S.D.): -2.8 +/- 18.5 (FM) and -3.5 +/- 16.4 (SH). Correlation coefficients (r) between WMSI calculated by SPECT and by echo were 0.715 (FM) and 0.789 (SH). Agreement between SPECT-WMSI and echo-WMSI was good for all imaging modes but better with SH compared to FM: 0.12 +/- 0.91 (FM), 0.10 +/- 0.77 (SH). The interobserver correlation coefficients (r) for the WMSI were 0.939 (FM) and 0.996 (SH). The agreement between the two observers was better for SH compared to FM. The systematic differences (mean differences) were 0.21 (FM) and -0.01 (SH), and the random differences between both observers (2 S.D.) decreased from 1.55 (FM) to 0.29 (SH). CONCLUSIONS: The use of SH echocardiography decreases the number of unscored segments. This results in an important gain in correlation and agreement for EF determination between echo and SPECT, and in a considerable decline of the interobserver variability for the echo-determined WMSI. WMSI determined by MIBI gated SPECT correlated closely with the SH WMSI, and agreement between both methods was excellent.

Aged↗
PubMed2000

Venous pooling during nitrate-stimulated tilt testing in patients with vasovagal syncope.

AIMS: To investigate the importance of venous pooling and variation in venous tone during nitrate-stimulated tilt testing in patients. METHODS: Ten patients with a history of vasovagal syncope underwent an upright tilt test after an injection of 99mTc-labelled albumin. A gamma camera was positioned at the level of the lower legs. The patients were tilted to 90 degrees for 30 min or until symptoms developed. In those subjects who did not show any symptoms before the end of the 30-min period, isosorbide dinitrate (ISDN) 5 mg was given sublingually and the test was prolonged for a maximum of 15 min. RESULTS: Nine of 10 patients needed nitrate stimulation to develop symptoms, and one patient remained symptom free following ISDN administration. Measurement of radioactivity revealed no significant increase in calf volume after nitrate stimulation (the mean volume increase was 77% before ISDN stimulation and a further 0.9% afterwards). CONCLUSIONS: The higher sensitivity for vasovagal syncope during upright tilt testing after administration of sublingual ISDN is not due to an increase in venous pooling in the lower extremities.

Administration, Sublingual↗
PubMed1999

Intravenous nitrates for pharmacological stimulation during head-up tilt testing in patients with suspected vasovagal syncope and healthy controls.

Nitrates may be used for pharmacological stimulation during tilt testing for the diagnosis of vasovagal syncope. In this study we assessed the diagnostic value of intravenous nitrates during tilt testing in patients with a typical history of vasovagal syncope. Twenty patients and 23 controls were tilted at 700 for a maximum duration of 30 minutes. After a 10-minute baseline supine phase, the test started with a continuous nitrate infusion at 1 microg/kg/min and increased every 5 minutes by 1 microg/kg/min, to a maximum of 6 microg/kg/min at the end of the test. The test was ended if the subjects developed a positive response (syncope or presyncope). Nineteen patients (95%) and 17 (74%) of the controls had a positive response. At test end sensitivity was 95%, but specificity was 26% and accuracy was 58%. Receiver operator characteristics (ROC) analysis revealed a maximum accuracy of 79% at 18 minutes, with a sensitivity of 80% and a specificity of 78%. Intravenous nitrates during tilt testing in patients with typical clinical criteria of vasovagal syncope is highly effective in provoking vasovagal syncope. Based on the ROC analysis, a maximum accuracy of 79% was attained at 18 minutes (at a dose of 4 microg/kg/min), suggesting a good diagnostic performance when tilt duration is limited to this point. A positive result requiring more than 18 minutes of stimulated tilting should be interpreted with caution, due to the accompanying considerable decrease of specificity.

Adult↗
PubMed1998

Contrast enhanced and functional magnetic resonance imaging for the detection of viable myocardium after infarction.

PURPOSE: Viable myocardium after acute myocardial infarction may be characterized by magnetic resonance imaging (MRI) either by demonstration of recovery of wall motion under dobutamine stress or by perfusion patterns after contrast medium administration. This study examines the relation between the two techniques. MATERIALS AND METHODS: Gradient-echo MRI at rest and under low-dose dobutamine stress was performed in 28 patients within the first 2 weeks after acute myocardial infarction. In addition, spin-echo MRI was performed after gadolinium-DOTA administration. Wall motion at rest and under stress was scored to assess the contractile reserve of the infarct regions. Infarct enhancement patterns were classified as subendocardial, transmural, or as a doughnut pattern. RESULT: Subendocardial or absent infarct enhancement was related to functional recovery under stress in 31 of 37 infarct segments. Transmural infarct enhancement was correlated with the absence of functional recovery in 10 of 17 infarct segments (p < 0.002), indicating nonviability. The doughnut pattern was exclusively associated with the absence of viability (five of five). CONCLUSION: Contrast enhancement patterns are related to residual myocardial viability.

Aged↗
PubMed1997

Randomised study of effect of ibopamine on survival in patients with advanced severe heart failure. Second Prospective Randomised Study of Ibopamine on Mortality and Efficacy (PRIME II) Investigators.

BACKGROUND: Drugs that improve symptoms in patients with heart failure must also be assessed for their effects on survival. Ibopamine stimulates DA-1 and DA-2 receptors and causes peripheral and renal vasodilatation; the drug improves symptoms of heart failure. We assessed the effect of ibopamine on survival in patients with advanced heart failure in a multicentre, randomised placebo-controlled study. METHODS: Patients with advanced severe heart failure (New York Heart Association classes III and IV) and evidence of severe left-ventricular disease, who were already receiving optimum treatment for heart failure, were randomly allocated oral ibopamine 100 mg three times daily or placebo. The primary endpoint was all-cause mortality. The study was designed to recruit 2200 patients, and the minimum duration of treatment would be 6 months. We did intention-to-treat and on-treatment analyses; a post-hoc subgroup analysis was also done. FINDINGS: After we had recruited 1906 patients the trial was stopped early, because of an excess of deaths among patients in the ibopamine group. 232 (25%) of 953 patients in the ibopamine group died, compared with 193 (20%) of 953 patients in the placebo group (relative risk 1.26 [95% CI 1.04-1.53], p = 0.017). The average length of follow-up was 347 days in the ibopamine group and 363 days in the placebo group. In multivariate analysis, only the use of antiarrhythmic drugs at baseline was a significant independent predictor of increased fatality in ibopamine-treated patients. INTERPRETATION: Ibopamine seems to increase the risk of death among patients with advanced heart failure who are already receiving optimum therapy, but the reasons for this increase are not clear. Our finding that antiarrhythmic treatment was a significant predictor of increased mortality in ibopamine-treated patients may be important, but exploratory analyses must be interpreted with caution.

Adult↗
PubMed1997

Clinical one-year outcomes after stenting in acute myocardial infarction.

We retrospectively review our results of 96 stent placements in 64 patients identified from our data base who received stents acutely and within 48 hr of acute myocardial infarction. The average age was 60 years; 77% were male. The average length of stay was 6.75 days. Three patients needed coronary artery bypass grafting (CABG) before discharge: 2 for stent occlusion and 1 for papillary muscle rupture. Need for CABG, further percutaneous transluminal coronary angioplasty (PTCA), myocardial infarction, and death defined outcome. Mean patient follow-up was 10.3 (+/-5.3) months. Seventy-two percent of patients were free of outcome events at 1 year, 17% needed CABG, and 11% required further PTCA. There were 2 myocardial infarctions and 1 death. Presence of left bundle branch block on admission electrocardiogram and angina in hospital after stent placement predicted worse outcome (P < 0.01).

Adult↗
PubMed1997

Sublingual nitrates during head-up tilt testing for the diagnosis of vasovagal syncope.

Pharmacologic stimulation during head-up tilt test (HUT) is used to increase the diagnostic yield of the test to detect vasovagal syncope. Reported lack of specificity of stimulation with intravenous isoproterenol has made a pharmacologic alternative desirable. Because nitrates are known to cause syncope of a vasovagal origin, we administered sublingual nitrates after classic tilt test in 32 patients with a history of typical vasovagal syncope and 20 healthy volunteers to assess the sensitivity, specificity, and accuracy of this new HUT technique. During the classic HUT four (13%) patients had syncope; after administration of sublingual nitrates, this number increased to 28 (87%). In the control group no subject had syncope during classic HUT, whereas during nitrate administration six (30%) had syncope. Sublingual nitrate stimulated HUT revealed a maximum accuracy of 83% at a cutoff point of 11 minutes, giving a sensitivity of 81% and specificity of 85%. Sublingual nitrate administration increased the accuracy of HUT in diagnosing vasovagal syncope in patients with a history of typical vasovagal syncope.

Administration, Sublingual↗
PubMed1997

Dipyridamole-induced angina pectoris during sestamibi stress test in patients with significant coronary artery disease: clinical, angiographic, and nuclear determinants.

Intravenous dipyridamole induces angina pectoris (AP) in some patients with significant coronary artery disease (CAD). The aim of this prospective study was to identify the angiographic, nuclear, and clinical determinants. The authors examined 50 patients consecutively with significant CAD on coronary angiography. All antiischemic medications were stopped twenty-four hours (nitrates only 6 hours) before injection of dipyridamole (0.84 mg/kg). ECGs were taken before, during, and after this injection. The regional myocardial activity of Tc-99m-Sestamibi at rest and after dipyridamole injection was measured with single-photon emission computed tomography (SPECT). During dipyridamole injection 20 patients had AP, of whom 15 had ST segment depression on ECG (P < 0.001). The only significant difference on coronary angiography between patients with dipyridamole-induced AP and those without AP was the presence of collaterals (P < 0.05). In patients with AP and collaterals, ECG and SPECT changes were always noted in the collateralized territory. Subgroup analysis showed that patients without previous myocardial infarction (MI, n = 17, P < 0.05) or nontransmural MI (n = 17, P < 0.05) had a good correlation between collaterals and AP, whereas patients with a history of transmural MI (n = 16) did not. No further significant variables could be found as a predictor of AP after dipyridamole injection. These findings suggest that AP during dipyridamole stress test is due to ischemia, which is not related to the severity of CAD. Ischemia is probably due to coronary steal to the collateralized territory in patients without transmural MI. Dipyridamole-induced angina pectoris is predictive for collaterals and may indicate viability in patients with MI.

Angina Pectoris↗
PubMed1996

Prediction of functional outcome after myocardial infarction using BMIPP and sestamibi scintigraphy.

UNLABELLED: We determined the predictive value of combined beta-methyl iodophenyl pentadecanoic acid (BMIPP) and sestamibi scintigraphy for the functional outcome after myocardial infarction and compared the value of this approach with dobutamine echocardiography. METHODS: Rest BMIPP, rest sestamibi and low-dose dobutamine echocardiographic studies were obtained in 18 patients 4 to 10 days after infarction (mean 6.7 +/- 2.0 days). Six months later, a rest echocardiographic study was performed to assess functional outcome. RESULTS: Wall motion improved in 27/33 segments (82%) which showed mismatching but not in 19/21 segments (90%) with matched defects (p < 0.001). The accuracy of combined BMIPP and sestamibi SPECT in predicting segmental functional outcome was higher (85%) than that of sestamibi uptake alone (77%). Wall motion improved in 16/20 segments (80%) showing contractile reserve and not in 21/34 segments (63%) with the negative dobutamine test, giving an accuracy of 69% for dobutamine echocardiography. Combination of the two techniques resulted in higher positive (94%) and negative predictive values (94%). CONCLUSION: Mismatching of BMIPP and sestamibi uptake is predictive for long-term functional recovery after acute myocardial infarction. In contrast, segments with matched defects contain only scar tissue. Combined BMIPP and sestamibi scintigraphy offers increased accuracy compared to dobutamine echocardiography.

Coronary Angiography↗
PubMed1996

Clinical nuclear cardiology: flow tracers and free fatty acid analogs to detect viable myocardium after infarction.

Among the available invasive and noninvasive modalities, nuclear cardiology techniques utilizing single photon emission computerized tomography (SPECT) have achieved a preeminent position for the assessment of myocardial viability. This arises from the rather unique potential of scintigraphic methods to assess myocardial perfusion, cell membrane integrity, and metabolic activity. The purpose of this article is to review the relative merits and limitations of myocardial flow tracers (thallium and sestamibi) and metabolic tracers (fatty acid analogs) to identify residual myocardial viability in patients with coronary artery disease and left ventricular dysfunction.

Cell Survival↗
PubMed1995

European postmarketing surveillance of ramipril in hypertension. 1. Feasibility and study cohort.

A prospective observational cohort study of the angiotensin inhibitor, ramipril, was undertaken in four countries within the European Community-Netherlands, United Kingdom, Germany and Belgium. A total of 10,377 consecutive patients with essential hypertension were recruited to the study with the aim of follow-up for one year. Overall 37% of doctors who agreed to participate in the study actually enrolled at least one patient. One third of the doctors who enrolled patients in the study entered two thirds of patients studied. Some 15% of participating males and 27% of females were aged over 70 years. Newly diagnosed hypertensives comprised 22% of the study cohort, the proportion being highest in UK and Netherlands, whereas 53% were established hypertensives of two or more years' duration, the proportion being highest in Germany and Belgium. There were substantial differences among the participating countries in the concurrent treatment these patients were receiving for hypertension, with two or more co-therapies being most frequent in Germany and Belgium. There were also substantial differences in co-therapies for concurrent diseases among the participating countries, reflecting both standard therapeutic practices in local areas and differences in marketing of drugs in the different countries. This report describes the initial findings of this multinational study and emphasises the need to consider several major potentially confounding variables in the analysis of the outcome events both in this study and in other collaborative observational international monitoring schemes for adverse drug reactions.

Aged↗
PubMed1995

Patient compliance and therapeutic coverage: comparison of amlodipine and slow release nifedipine in the treatment of hypertension. The Belgian Collaborative Study Group.

To study patient compliance in hypertensive outpatients amlodipine (5 mg once daily) and slow release nifedipine (20 mg twice daily) were compared in an open, crossover study in general practices. Four methods of assessment for patient compliance (pill count, taking compliance, days with correct dosing, timing compliance) were used in both study arms. For the latter three assessment a special device, the medication event monitoring system, was used to record the time and date of each opening and closure of the container. The compliance of the 320 hypertensive patients with once-daily amlodipine was markedly superior to twice-daily slow release nifedipine. Therapeutic coverage was also significantly better for amlodipine in the hypertensive patients. Amlodipine was better tolerated than nifedipine slow release. Patient compliance and therapeutic coverage with the calcium antagonist amlodipine given once daily was superior to slow release nifedipine b.d. in hypertensive outpatients recruited in general practice.

Amlodipine↗
PubMed1994

Magnetic resonance imaging of the heart in a case of hepatocellular carcinoma extending into the right atrium.

Hepatocellular carcinoma is the most common primary malignant liver tumor occurring in more than 1 million cases a year all over the world. Vascular invasion is known to occur in 30% of patients at initial presentation [1]. An extension of the tumor into the right atrium is well described in the literature [2], with surgical resection as the only procedure available. But the diagnosis is often difficult before death. We report a case in which magnetic resonance imaging of liver and heart shows the extension of this tumor into the right atrium.

Aged↗