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Abstract-White coat hypertension (WCH) is common in referred hypertensive patients. Ambulatory blood pressure monitoring (ABPM) is not free from the white coat syndrome. We examined the use of the elevation of the first and last measurements of ABPM for diagnosis of WCH in a hypertensive population that had been referred to a hospital-based hypertension unit. hite coat hypertension is a common finding in hypertensive populations and in the population at large. The incidence has variably been recorded between 12% and 50%, depending on definitions. 1 The importance of the condition lies in the relatively benign cardiovascular risk with which it is associated compared with established hypertension. 2 The phenomenon of white coat hypertension may reflect an abnormally vigorous sympathetic response to the environment of the measurement, 3 especially the presence of the measuring nurse or physician. 4 Ambulatory blood pressure (BP) is the most frequent mechanism used in measuring the presence of the white coat effect. The standard definition of white coat hypertension is an elevation of clinic pressure with a normal daytime ambulatory profile. 5 However, our experience has been that the initial few measurements on the ambulatory monitor, and, indeed, the final measurement, which reflect the patient's attention to attaching and removal of the monitoring device, respectively, are frequently abnormal also. A typical ambulatory monitor recording from such a patient is shown in Figure 1. This study has been undertaken, therefore, to establish the clinical usefulness of the first and last measurement of ambulatory monitoring in the diagnosis of white coat hypertension. MethodsThe patient population used in this study was a cohort of 1350 patients, drawn from a total database population of 2425 patients, who attended the "shared care" hypertension management program in our institution for assessment of their hypertension. The patient exclusion protocol is depicted in Figure 2. All patients were classified as hypertensive if the referral physician-recorded clinic BP was Ն140 mm Hg systolic or 90 mm Hg diastolic. 6 None of the patients were on vasoactive medications at the time of monitoring, and subjects were excluded if antihypertensive drugs had been taken within 2 weeks of the study.Upon arrival for ambulatory monitoring, the patient had clinic BP measurement performed by the attending nurse in the BP unit. BP was measured in the nondominant arm after 5 minutes of quiet sitting; the BP measurement was taken in accordance with the recommendations of the British Hypertension Society. 7 Only patients in whom both this clinic BP and the original referral BP were above normal were included in the analysis. ECG was performed with the use of a standard 12 lead placement within 1 week of attendance at the BP unit, and left ventricular voltage criteria for ventricular mass

Objective: To assess submillimetre coronary computed tomographic angiography (CTA) in comparison with invasive quantitative coronary angiography as the gold standard and to examine the effect of significant coronary artery calcification (CAC), which is known to impede lumen visualisation, on the accuracy of the examination. Methods: After invasive coronary angiography, 58 patients underwent coronary imaging with a GE Lightspeed 16 computed tomography (CT) system. CAC was quantified after an ECG triggered acquisition with a low tube current. Coronary CTA was performed with retrospective ECG gating and a 16 6 0.63 mm collimation and was reconstructed with an effective 65-250 ms temporal resolution. All 13 major coronary artery segments were evaluated for the presence of > 50% stenosis, and compared with the gold standard. Results: One patient moved and could not be evaluated. All segments (except occluded segments) were evaluated for 57 patients. Overall the accuracy of coronary CTA for detection of > 50% stenosis was: sensitivity 83%, specificity 97%, positive predictive value 80%, and negative predictive value 97%. The number of diseased coronary arteries was correctly diagnosed in 34 of 38 (89%) patients overall. Altogether 21 of 57 (37%) patients had a CAC score > 400, which was predefined as representing significant CAC. Excluding these patients from the analysis improved the accuracy of coronary CTA to a sensitivity of 89%, specificity 98%, positive predictive value 79%, and negative predictive value 99%. Conclusions: Non-invasive coronary angiography with submillimetre CT is reliable and accurate. It appears that a subgroup of patients may be selected based on CAC score in whom the investigation has even higher accuracy. Coronary CTA has reached the stage where it should be considered for a clinical role. Further research is required to define this role.T he emergence of ECG gated multislice computed tomography (CT) has stimulated great interest among cardiologists. This is primarily because this new technology may provide a clinically useful method for performing non-invasive coronary angiography. Four slice CT has been extensively evaluated in this context and is lacking in both reliability of image quality and accuracy of results. [1][2][3][4][5] However, these studies have identified certain patient related factors that appear to affect the provision of a clear image of the contrast enhanced coronary artery lumen. Specifically, high heart rates induce motion artefact and excessive coronary artery calcification (CAC) impedes accurate lumen visualisation and may produce blooming artefacts. 6 Recently four slice CT has been superseded by 16 slice CT. For cardiac applications this technology provides not only a submillimetre collimation but also improved temporal resolution. Preliminary studies have been performed with this type of technology.7-9 Although the results of these studies have been favourably received, improvements are still needed before clinical use. 10

Background:The issue as to whether white coat hypertension is a pathologically significant entity, with associated target organ changes, or that the condition carries the same risk for target organ involvement as normotension, is undecided. Previous studies which have shown pathological correlates between white coat hypertension and target organ damage have not controlled for the most obvious confounder, mean 24 h blood pressure (BP). Methods and results: In this study we retrospectively identified 33 age and sex-matched pairs, one group with normal BP, the other with white coat hypertension. The white coat hypertensive group showed significantly greater left ventricular mass indexed for body surface area than normal controls (99.0 g/m 2 vs 78.3 g/m 2 , P Ͻ

The authors assessed motion artifact of the thoracic aorta in 25 patients who underwent multi-detector row computed tomography (CT) with retrospective electrocardiographic (ECG) gating. CT reconstructions centered at four phases of diastole were compared for five different levels of the thoracic aorta. A significant positive correlation was observed between heart rate and motion artifact (r = 0.72, P <.001). The optimal reconstruction phase varied between patients, and this was directly related to heart rate. For patients with a heart rate of 70 beats per minute, the reconstruction phase centered at 75% of the R-R interval had the significantly least motion artifact (P =.004). Conversely, the optimal reconstruction phase for patients with heart rates above 70 beats per minute was centered at 50% of the R-R interval (P =.09).

The mean costs of admission and LOS for patients with non-specific chest pain are significant. Extrapolating findings, annual national cost is estimated at approximately €71 million for this cohort, with 73,000 bed days consumed nationally. Delays from admission to tests and low percentage of weekend discharges prolong LOS.

Background: Chronic constitutional hypotension has been described in a proportion of the population, and has a symptom complex ascribed to it. The true prevalence of low blood pressure in the normal population has not been defined. Aim of study: This study was undertaken to determine the prevalence of low blood pressure states, as measured using ambulatory blood pressure monitoring, in a general population cohort, and to determine the association between low blood pressure and clinical and demographic variables. Patient population: The population enrolled were a cohort of mainly urban dwelling Irish subjects, either employees or spouses of employees of a major national bank. Methods: Subjects had an ambulatory blood pressure monitor fitted between 09.00 and 12.00 and wore the monitor for 24 hours. The subjects also filled out a detailed lifestyle questionnaire, and kept an activity

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