The Role of Ambulatory Blood Pressure Monitoring in Current Clinical Practice.

Hypertension continues to be the leading modifiable risk factor for stroke, kidney disease and cardiovascular disease, and it also plays a key role in a significant proportion of preventable deaths globally. Ambulatory blood pressure monitoring (ABPM) is an underutilised tool that augments the accurate diagnosis of hypertension. Out-of-office blood pressure measurements such as ABPM, permits the diagnosis of white coat hypertension and masked hypertension as well as determining a patient's nocturnal dipping status. These common clinical phenotypes have relevance with regard to clinical outcomes and may impact management. Overall, the diagnosis and management of hypertension presents numerous challenges, requiring the complementary use of multimodal blood pressure monitoring. Familiarity with the use of ABPM is important in the optimal management of patients, particularly as it becomes more accessible with the recent introduction of a Medicare Benefits Schedule item number.

Clinical screening tools for obstructive sleep apnea in a population with atrial fibrillation: a diagnostic accuracy trial.

STUDY OBJECTIVES: Although obstructive sleep apnea (OSA) is a known risk factor for atrial fibrillation (AF), there is a paucity of data around its diagnosis and management in patients with AF. The objectives of this study were to compare the diagnostic accuracy of commonly used OSA screening tools in an AF population, including a level 3 portable sleep study device, and to examine the epidemiology of OSA in a hospital cohort with AF. METHODS: One hundred seven patients with AF recruited from 2 tertiary centers underwent a panel of OSA screening tools and in-laboratory polysomnography in randomized order. RESULTS: Oxygen desaturation index derived from a level 3 portable sleep study device performed best for moderate to severe and severe OSA, with excellent diagnostic accuracy (area under the curve, 0.899; 95% confidence interval, 0.838-0.960 and area under the curve, 0.925; 95% confidence interval, 0.859-0.991, respectively). Sixty-seven patients (62.6%) were newly diagnosed with OSA (31.8% mild, 18.7% moderate, 12.1% severe). CONCLUSIONS: Undiagnosed OSA is highly prevalent in a hospital AF cohort. However, it is characterized by a relative paucity of symptoms, markedly limiting the usefulness of history or screening questionnaires. This is the first study to find that a level 3 home sleep study device shows excellent diagnostic accuracy in patients with AF. This finding may inform AF management guidelines. CLINICAL TRIAL REGISTRATION: Registry: Australian New Zealand Clinical Trials Registry; Name: The validity and reliability of a portable device for the diagnosis of Obstructive Sleep Apnoea in patients with Atrial Fibrillation; URL:https://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?id=371024; Identifier: ACTRN12616001016426.

Electrocardiographic QRS duration is influenced by body mass index and sex.

BACKGROUND: Electrocardiogram (ECG) measured QRS duration has been shown to influence cardiovascular outcomes. However, there is paucity of data on whether ECG QRS duration is influenced by obesity and sex in large populations. METHODS: All ECGs performed by a pathology provider over a 2-year period were included. ECGs with confounding factors and those not in sinus rhythm were excluded from the primary analysis. RESULTS: Of the 76,220 who met the inclusion criteria, 41,685 (55%) were females. The median age of the study cohort was 61 years (interquartile [IQR] range 48-71 years). The median QRS duration was 86 ms (IQR 80-94 ms). The median BMI was 27.6 kg/m2 (IQR 24.2-31.8 kg/m2). When stratified according to the World Health Organization classification of BMI < 18.50 kg/m2, 18.50-24.99 kg/m2, 25.00-29.99 kg/m2, and ≥ 30.00 kg/m2, the median QRS durations were 82 ms (IQR 76-88 ms), 86 ms (IQR 80-92 ms), 88 ms (IQR 80-94 ms) and 88 ms (IQR 82-94 ms), respectively (p < 0.001 for linear trend). Median QRS duration for females was 84 ms (IQR 78-88 ms); for males, it was 92 ms (IQR 86-98 ms), p < 0.001. Compared to males, females had narrower QRS complexes at similar age and similar BMI. In multiple linear regression analysis, BMI correlated positively with QRS duration (standardized beta 0.095, p < 0.001) independent of age, sex, and heart rate. CONCLUSIONS: In this large cohort there was a positive association between increasing BMI and QRS duration. Females had narrower QRS duration than males at similar age and similar BMI.