Association of osteoprotegerin with ascending aortic dissection

Background

Thoracic aortic dissections are among the cardiovascular diseases with the highest mortality rates. Their often belated diagnosis and, hence, poor prognosis call for further research of their pathophysiology and possible biomarkers that will aid early diagnosis and increase survival rates. Osteoprotegerin is a known biomarker in cardiovascular disease, but it is yet to be determined whether it participates in aortic disease and thoracic aortic dissection in particular.

Purpose

This clinical study aimed at researching the role of osteoprotegerin in thoracic aortic aneurysm and dissection.

Methods

We compared three groups of patients; 20 patients with ascending aortic aneurysm (AAA), 10 patients with acute ascending aortic dissection (AAD) and 16 patients with normal aortic diameter undergoing cardiac surgery for other indication (control group). Serum samples were obtained from patients before surgery and osteoprotegerin levels were measured using the ELISA method.

Results

One-way analysis of variance revealed a significant association between the examined groups of patients and levels of osteoprotegerin (AAD: 62.72±44.53 pmol/L, AAA: 33.43±8.08 pmol/L, Control: 48.61±29.47 pmol/L, p=0.03). Importantly, after post-hoc analysis osteoprotegerin levels were found to be increased in patients with AAD compared to patients with uncomplicated AAA (62.72±44.53 pmol/L vs 33.43±8.08 pmol/L, p=0.03) (Figure 1), whereas there was no statistically significant difference between patients with AAA and the control group (33.43±8.08 pmol/L vs 48.61±29.47 pmol/L, p=0.34).

Conclusions

These findings suggest that osteoprotegerin may participate in the pathophysiology of aortic dissection but not in mechanisms of aortic dilatation. Therefore, detection of elevated osteoprotegerin levels in patients with diagnosed ascending aortic aneurysms might suggest an increased probability of dissection and, therefore, aid the decision-making process.

Figure 1

Funding Acknowledgement

Type of funding source: None

P4392A systematic review and meta-analysis of the cardiovascular effects of e-cigarette

Background

Electronic cigarette (EC) is marketed as a safe alternative to tobacco smoking, but EC cardiovascular effects remains largely unknown.

Purpose

To systematically review and meta-analyse published literature to investigate the cardiovascular effects and associated risk from EC use.

Methods

We searched PubMed from January 2000 until November 2017 for published studies assessing the cardiovascular effects of EC. For each eligible study we used the mean difference (MD) with 95% confidence intervals (CIs) for SBP, DBP and HR. The pooled MDs for each outcome of interest were calculated by using a fixed effects model. The presence of heterogeneity among studies was evaluated by the I2 statistic.

Results

We report conflicting evidence on the effects of EC on heart rate and blood pressure, which is mainly based on non-randomized clinical studies of moderate quality. In a meta-analysis of 14 studies (n=441 participants), that despite the negative effects of EC on heart rate (pooled MD=2.27, 95% CI: 1.64 to 2.89, p<0.001), diastolic (DBP, pooled MD=2.01mmHg, 95% CI: 0.62 to 3.39, p=0.004) and systolic blood pressure (SBP, pooled MD=2.02mmHg, 95% CI: 0.07 to 3.97, p=0.042), benefits may be observed in terms of blood pressure regulation when switching from tobacco smoking to EC (SBP pooled MD=−7.00, 95% CI: −9.63 to −4.37, p<0.001; DBP pooled MD=−3.65, 95% CI: −5.71 to −1.59, p=0.001). Evidence suggests that EC negatively affects endothelial function, arterial stiffness and the long-term risk for coronary events, but these findings are derived from single study reports and have not been confirmed in additional studies.

Conclusions

We report adverse effects of EC use on heart rate and blood pressure. Unless supported by stronger evidence, EC should not be labelled as cardiovascular safe products. Future studies should delineate whether EC use is less hazardous to cardiovascular health than conventional cigarette smoking.