Stephen J. Leslie

Management of chronic heart failure due to systolic left ventricular dysfunction by cardiologist and non-cardiologist physicians.

There are now a number of guidelines outlining the diagnosis and management of patients with chronic heart failure (CHF). The extent to which these guidelines are used and the effects on patient outcomes are not well known. The aim of this study was to examine the implementation of a heart failure guideline among cardiologist and non‐cardiologist physicians in a university hospital setting. Case record data were examined from 400 patients with a primary diagnosis of CHF. Management of these patients was assessed using a systolic heart failure guideline (Scottish Intercollegiate Guideline Network, number 35) as a benchmark. Hospital admission data were examined contemporaneously over a 17‐month period to assess associations between adherence to drug therapies and number of admissions. Overall, there was poor adherence to the guideline, with relatively high use of angiotensin‐converting enzyme (ACE) inhibitors/angiotensin II receptor blockers (ARBs) (80%), low use of beta‐blockers (32%) and digoxin (36%), and very low use of spironolactone (13%). Cardiologists used more beta‐blockers (37 vs. 21%, P=0.003) and digoxin in sinus rhythm (18 vs. 5%, P<0.001) than non‐cardiologists. Hospital admission rate was individually associated with increasing age, NYHA status, beta‐blocker, diuretic and spironolactone prescription (all P<0.001). At multivariable analysis, only age, NYHA status and increased diuretic prescription were associated with more frequent admission (P<0.001, R2=0.15). Despite carefully designed guidelines, the implementation of evidence‐based therapies for CHF remains inadequate, even in a university hospital environment. This may reflect a lack of organisational developments to facilitate the increasingly complex management of patients with CHF.

Validation of laser Doppler flowmetry coupled with intra-dermal injection for investigating effects of vasoactive agents on the skin microcirculation in man

ObjectiveTo determine the reproducibility of laser Doppler flowmetry coupled with intra-dermal saline delivery.MethodsDelivery of saline was judged visually by two operators (n=100), using a graduated syringe (Becton-Dickinson), by expelling saline onto a weighing boat. Volume was assessed by weight. Skin blood flow following intra-dermal injection of saline was assessed in 18 healthy volunteers; 10 attended twice to assess between-day reproducibility, and 8 attended once to assess between-site reproducibility. Results are expressed as mean value±SEM and 95% confidence interval for mean differences.ResultsThere was no difference between operators in mean injection weight, both weights being 10.3±0.1xa0mg (mean difference 0.08, 95% confidence interval, CI −0.23 to 0.39xa0mg; n=100, P=0.9). Intra-dermal saline caused a nine-fold increase in blood flow (0.03±0.003 to 0.27±0.02 perfusion units, PU; n=18, P<0.001). This response had a rapid onset, with the maximal effect seen at 4xa0min and a duration of greater than 30xa0min. There was no difference in the magnitude of the response between the dominant and non-dominant arms, AUC was 2.9±0.4 and 2.9±0.4, respectively (mean difference −0.05, 95% CI −0.8 to 0.73 PU; n=18, P=0.93). However, there was a trend towards differences between study visits 1 and 2: AUC was 3.2±0.6 and 2.0±0.5, respectively (mean difference 1.2, 95% CI −0.03 to 2.43 PU; n=10, P=0.7). There was no difference in the magnitude of responses between different sites on the forearm (n=64, P=0.6).ConclusionsThese studies demonstrate that the technique of laser Doppler flowmetry coupled with intra-dermal injection is a safe, well-tolerated technique with good reproducibility. A trend towards reduced between-day reproducibility emphasizes the importance of vehicle control sites when investigating the effects of vasoactive compounds. This technique provides a reliable method for the intra-dermal delivery of drugs, despite the direct effect of injection of saline on blood flow.

No adverse hemodynamic interaction between sildenafil and red wine

Our objective was to investigate the hemodynamic interaction between sildenafil and red wine. Sildenafil citrate (Viagra), a phosphodiesterase type 5 inhibitor, is an effective treatment for male erectile dysfunction that potentiates nitric oxide–mediated vasodilation. Alcohol is a commonly used recreational substance with complex vascular effects, which may, in part, be mediated by nitric oxide. Thus there is potential for an adverse hemodynamic interaction.

Harmonic imaging improves estimation of left ventricular mass

Objectives: To assess the effect of tissue harmonic imaging (THI) on assessment of left ventricular mass index (LVMI) measurements by M-mode trans-thoracic echocardiography, when compared with magnetic resonance imaging (MRI). Methods: 20 hypertensive male subjects were studied. LVMI was measured in all subjects by both gradient-echo MRI (Lscelsint Prestige 1.9 T) and by transthoracic echocardiography (ATL HDI 5000). M-mode echocardiography recordings were taken for each patient, two with fundamental imaging (FI) and two using THI in a randomised order and the images unlabelled. Recordings were analysed off-line, by a blinded observer. LVMI by MRI was calculated using Simpsons rule on serial short axis slices of 8 mm thickness. Data are expressed as mean ± SD. Results: There was a difference in LVMI measurements between FI and THI (LVMI) (79 ± 20 vs. 93 ± 25 g2; p < 0.001). A lower mean difference was obtained by THI, compared to FI, when compared with MRI (2 ± 15 vs. −32 ± 22 g2; p < 0.001) suggesting that FI underestimates LVMI. Inter-observer variability was similar between THI and FI (4.5 ± 15 vs. 6.4 ± 15 g2; p = 0.46). Conclusion: In hypertensive males, M-mode echo derived from FI underestimated LVMI. These results imply that widely accepted reference ranges for LVMI using FI are not applicable when THI is used.