Should we look for silent pulmonary embolism in patients with deep venous thrombosis?

BACKGROUND: Asymptomatic or silent pulmonary embolism (S-PE) in patients with deep vein thrombosis has been the focus of numerous publications with the objective of determining the incidence of S-PE and assessing whether its existence has any clinical or therapeutic consequences that outweigh the risks associated with the diagnostic tests performed and the increased healthcare costs. The objectives were to assess the incidence of S-PE using computed tomography angiogram (CTA), to understand the epidemiological factors that might trigger embolism, and to assess whether D-dimer (DD) predicts the existence of S-PE's. METHODS: A prospective and consecutive assessment of 103 hospitalized patients with lower limb DVT in the absence of PE symptoms, using CT scan. DD was quantified before anticoagulation. The risk factors and characteristics of the DVT were studied. A three-year follow-up assessing risk recurrence and clinical outcome was performed. RESULTS: The incidence of S-PE was 66%. In 77% of these cases, the main and lobar pulmonary arteries were affected. Iliac and femoral DVTs most often produced S-PE. ROC curve with a DD value higher than 578 ng/ml provided good sensitivity but low specificity to identify patients with S-PE. Diagnosis entailed higher hospitalization expenses. No significant recurrence rate of thrombotic events was observed in the S-PE group during the follow-up. CONCLUSIONS: The incidence of S-PE in lower-limb DVT is high, but in the absence of symptoms, diagnosis does not appear to be necessary, as there are no short- or long-term clinical or therapeutic consequences.

Efficacy in angiotensin receptor blockade: a comparative review of data with olmesartan.

A range of angiotensin II receptor blockers (ARB) is available, and analyses suggest there are differences between agents in terms of antihypertensive efficacy and 24-hour blood pressure control.This review assesses the data comparing olmesartan with other ARBs in terms of blood pressure reductions, goal achievement, 24-hour control and speed of onset. Olmesartan seems to have a more favourable efficacy profile relative to standard doses of the ARBs used in comparative studies; results consistent with the high degree of blockade of the angiotensin II type 1 receptor for olmesartan.Taken together, there might be differences between ARBs regarding their blood pressure lowering efficacy, and these results may provide further support of the benefits of olmesartan therapy since choice of an effective agent is crucial in antihypertensive therapy.

Renin polymorphisms and haplotypes are associated with blood pressure levels and hypertension risk in postmenopausal women.

BACKGROUND: Renin is a key protein of the renin-angiotensin system involved in the physiological control of blood pressure; the renin gene is therefore a candidate for essential hypertension in humans. We tested the association between polymorphisms and haplotypes of the renin gene and the risk of hypertension and blood pressure levels in two Spanish populations. METHODS: Two population-based studies from different regions of Spain were performed. Study A included 1502 individuals (748 women) 40-70 years old, and Study B included 670 women 45-70 years old. Fourteen polymorphisms of the renin gene were selected based on position, spacing, heterozygosity (> 10% for the minor allele frequency) and previous information, and were assessed by SNPlex. RESULTS: Genotype GG of the rs5707 polymorphism was significantly associated with blood pressure levels (P = 0.005) and with the risk of having hypertension (odds ratio, 6.16; 95% confidence interval, 1.19-31.8) in women 40-70 years old from study A, but not the men. This association was also present in the women of study B (P < 0.001 for blood pressure values; odds ratio, 2.11 and 95% confidence interval, 1.07-4.17 for hypertension). Two haplotypes defined by five selected polymorphisms were associated with increased risk of hypertension in these aged women. CONCLUSION: Polymorphisms of the renin gene were associated with blood pressure levels and risk of hypertension in women over 40 years old. The interaction between the potential functional impact of this genetic background and the estrogen fall could explain the association in women of this age group.

Antihypertensive activity of angiotensin II AT1 receptor antagonists: a systematic review of studies with 24 h ambulatory blood pressure monitoring.

OBJECTIVE: To perform a systematic review of the antihypertensive activity of the angiotensin II AT1 receptor antagonists (ARB). METHODS: Studies in which blood pressure (BP) was measured using ambulatory BP monitoring for at least 24 h were collected from MEDLINE. Data for each treatment group, ARB, placebo or the drug used for its comparison were obtained from the selected studies. Only studies with a minimum of quality criteria were selected. The final study group contained 36 publications, with a total of 47 patient cohorts receiving ARB in monotherapy, 10 with placebo, 10 with amlodipine, and five with enalapril. The reduction in clinical and ambulatory BP during 24 h, day, night and the last 4-h period for each of the drugs analysed were calculated and adjusted by age, sex, number of participants and by the initial BP level. RESULTS: The global antihypertensive activity of ARB differs from that observed with amlodipine in the sense that the magnitude of the reduction in the BP values does not essentially depend on the initial BP values nor on the dose used. When only ARB were considered, the drug used was a determinant for systolic BP reduction, whereas for diastolic BP the influence was on the BP reduction and the duration of the antihypertensive activity. The dose used had a particular influence on the duration of the antihypertensive activity for both systolic and diastolic BP. CONCLUSION: Among the ARB, the influence is on duration more than on the magnitude of BP reduction. Dose, therefore, is an important factor in the duration of antihypertensive activity.

[Factors related to the differences in blood pressure values assessed by auscultatory or oscillometric methods]. / Factores que influyen en la diferencia de medida de presión arterial entre el método auscultatorio y el oscilométrico.

BACKGROUND AND OBJECTIVE: Measurement of blood pressure by using the auscultatory method coupled with mercury sphygmomanometer is rapidly being replaced for monitor using the oscillometric one. Discrepancies between the two methods and the factors related to them were analyzed in a large subset of adults. MATERIAL AND METHOD: Blood pressure values were obtained sequentially in the same arm by using a mercury sphygmomanometer and a Spacelabs monitor devices. The relationship between both kinds of measurements was assessed by the Pearson's correlation coefficients and the concordance by using the Bland and Altman method. Differences between the two methods were calculated and the factors related to the differences were sought by multiple regression models. RESULTS: A total of 1,742 adult subjects were analyzed. Pearson's correlation coefficients were 0.927, 0.922, 0.886, 0.962 for SBP, DBP, MBP and PR, respectively. Oscillometric method overestimate and infraestimate SBP values in the two extreme of SBP values, the lowest SBP the highest the values and vice versa. A similar trend was observed for DBP although the differences were minor. Pulse wave amplitude explains the 24% of the variance observed for SBP and arm circumference the 8% for DBP. CONCLUSIONS: Blood pressure values measured by oscillometric methods are influenced for pulse wave amplitude and by the arm circumference. These need to be taken in account when blood pressure assessment is obtained by using this method.