Jenny Louise Bacon

Dual-Energy CT for Imaging of Pulmonary Hypertension: Challenges and Opportunities

Computed tomography (CT) is routinely used in the evaluation of patients with pulmonary hypertension (PH) to assess vascular anatomy and parenchymal morphology. The introduction of dual-energy CT (DECT) enables additional qualitative and quantitative insights into pulmonary hemodynamics and the extent and variability of parenchymal enhancement. Lung perfusion assessed at pulmonary blood volume imaging correlates well with findings at scintigraphy, and pulmonary blood volume defects seen in pulmonary embolism studies infer occlusive disease with increased risk of right heart dysfunction. Similarly, perfusion inhomogeneities seen in patients with PH closely reflect mosaic lung changes and may be useful for severity assessment and prognostication. The use of DECT may increase detection of peripheral thromboembolic disease, which is of particular prognostic importance in patients with chronic thromboembolic PH with microvascular involvement. Other DECT applications for imaging of PH include low-kilovoltage images with greater inherent iodine conspicuity and iodine-selective color-coded maps of vascular perfusion (both of which can improve visualization of vascular enhancement), virtual nonenhanced imaging (which better depicts vascular calcification), and, potentially, ventricular perfusion maps (to assess myocardial ischemia). In addition, quantitative assessment of central vascular and parenchymal enhancement can be used to evaluate pulmonary hemodynamics in patients with PH. The current status and potential advantages and limitations of DECT for imaging of PH are reviewed, and current evidence is supplemented with data from a tertiary referral center for PH.

Measuring the acute cardiovascular effects of shisha smoking: a cross-sectional study

Objectives To investigate the acute cardiovascular effects of smoking shisha. Design A cross-sectional study was carried out in six shisha cafes. Participants smoked shisha for a period between 45 min (minimum) and 90 min (maximum). The same brand of tobacco and coal was used. Setting London, UK. Participants Participants were those who had ordered a shisha to smoke and consented to have their blood pressure, heart rate and carbon monoxide levels measured. Excluded subjects were those who had smoked shisha in the previous 24 h, who smoke cigarettes or who suffered from cardiorespiratory problems. Main outcome measures Blood pressure was measured using a sphygmomanometer. Pulse was measured by palpation of the radial artery. Carbon monoxide levels were obtained via a carbon monoxide monitor. These indices were measured before the participants began to smoke shisha and after they finished or when the maximum 90 min time period was reached. Results Mean arterial blood pressure increased from 96 mmHg to 108 mmHg (p < 0.001). Heart rate increased from 77 to 91 bpm (p < 0.001). Carbon monoxide increased from an average of 3 to 35 ppm (p < 0.001). A correlation analysis showed no relationship between carbon monoxide and the other indices measured. Conclusion The acute heart rate, blood pressure and carbon monoxide levels were seen to rise significantly after smoking shisha. The weak correlation between carbon monoxide levels and the other variables suggests that carbon monoxide levels had not contributed to their significant increase.

Indications and interventional options for non-resectable tracheal stenosis

Non-specific presentation and normal examination findings in early disease often result in tracheal obstruction being overlooked as a diagnosis until patients present acutely. Once diagnosed, surgical options should be considered, but often patient co-morbidity necessitates other interventional options. Non-resectable tracheal stenosis can be successfully managed by interventional bronchoscopy, with therapeutic options including airway dilatation, local tissue destruction and airway stenting. There are common aspects to the management of tracheal obstruction, tracheomalacia and tracheal fistulae. This paper reviews the pathogenesis, presentation, investigation and management of tracheal disease, with a focus on tracheal obstruction and the role of endotracheal intervention in management.

The Pathophysiology, Presentation and Diagnostic Investigation of Pulmonary Hypertension

The definition of pulmonary hypertension (PH) is an elevated resting mean pulmonary artery pressure (mPAP) of greater than or equal to 25 mmHg, determined by right heart catheterisation [1]. It is a progressive and ultimately fatal disease without appropriate management. Many different diseases can be associated with this elevation in mPAP and therefore PH is a diverse clinical entity.

Current Treatment Strategies, Guidelines and New Therapies

Historically, primary pulmonary hypertension (as it was then termed) has been considered a rapidly progressive, fatal condition with no effective therapies with an average life expectancy of less than 3 years at diagnosis [1]. It has been labelled as a “desperate disease” and upon diagnosis one enters “the kingdom of the near-dead” [2].