Predictors and Rate of Progression of Aortic Root and Ascending Aorta Dilatation

Thoracic Aortic Aneurysm Growth Rates and Predicting Factors: A Systematic Review and Meta-Analysis

BACKGROUND

Thoracic aortic aneurysm (TAA) is an indolent, potentially fatal disease, which progresses at variable rates that are influenced by pathogenesis and patient characteristics. We conducted a systematic review and meta-analysis to synthesize the current evidence on growth rate (GR) and predictive factors among patients with syndromic and nonsyndromic heritable thoracic aortic disease, bicuspid aortic valve, and sporadic TAA.

METHODS AND RESULTS

Online databases were searched for studies that reported aortic growth on adult patients with asymptomatic TAA. Pooled GRs were calculated for 3 different TAA groups: syndromic heritable thoracic aortic disease, bicuspid aortic valve, and sporadic TAA. The search yielded 6297 studies, of which 85 were included in the systematic review, and 55 in the meta-analysis of growth rate (10 syndromic heritable thoracic aortic disease, 31 bicuspid aortic valve, and 34 sporadic subgroups). Mean observed TAA GR was 0.25 mm/y (95% CI, -0.18 to 0.68) in Turner syndrome, 0.45 mm/y (95% CI, 0.00-0.90) in Marfan syndrome, and 0.81 mm/y (95% CI, -0.46 to 2.08) in Loeys-Dietz syndrome. The mean observed GR in patients with bicuspid aortic valve before aortic valve surgery was 0.37 mm/y (95% CI, 0.29-0.46), compared with 0.18 mm/y (95% CI, 0.14-0.33) in postsurgical studies. Mean observed GR in sporadic ascending TAA was 0.33 mm/y (95% CI, 0.13-0.52) and 2.71 mm/y (95% CI, 0.53-4.88) in descending TAA.

CONCLUSIONS

Considering all pathogeneses, ascending TAAs typically grow at 0.25 to 1 mm/y, and thus annual surveillance is likely too frequent to detect growth in most patients. Studies vary widely in populations, methodology, and outcomes, with few high-quality longitudinal studies and no predictors of aortic GR.

Evolution and outcomes of aortic dilations in giant cell arteritis

OBJECTIVES

To identify factors associated with the progression of giant cell arteritis (GCA)-related or associated aortic dilations.

METHODS

In this retrospective study, 47 GCA patients with aortic dilation were longitudinally analyzed. Each patient underwent ≥2 imaging scans of the aorta during the follow-up. Three progression statuses of aortic dilations were distinguished: fast-progressive (FP) defined by a progression of the aortic diameter ≥5 mm/year or ≥1 cm/2 years, slow progressive (SP) by a progression of the aortic diameter >1 mm during the follow-up, and not progressive (NP) when aortic diameter remained stable.

RESULTS

Among the 47 patients with aortic dilation, the thoracic section was involved in 87 % of patients. Within a total follow-up of 89 [6-272] months, we identified 13 (28 %) patients with FP dilations, and 16 (34 %) and 18 (38 %) patients with SP and NP dilations, respectively. No differences regarding baseline characteristics, cardiovascular risk factors or treatments were observed among the 3 groups. However, FP patients more frequently showed atheromatous disease (p = 0.04), with a more frequent use of statins (p = 0.04) and antiplatelet agents (p = 0.02). Among the 27 (57 %) patients with aortitis, aortic dilation developed on an inflammatory segment in 23 (85 %). Among the FP patients who underwent aortic surgery with available histology (n = 3), all presented active vasculitis.

CONCLUSION

This study suggests that aortic inflammation, as well as atheromatous disease, might participate in the fast progression of aortic dilation in GCA.

Aortic Root Dimension Using Transthoracic Echocardiography: Results from the Copenhagen City Heart Study

Findings regarding the relation between aortic size and risk factors are heterogeneous. This study aimed to generate new insights from a population-based adult cohort on aortic root dimensions and their association with age, anthropometric measures, and cardiac risk factors and evaluate the incidence of acute aortic events. Participants from the fifth examination round of the Copenhagen City Heart study (aged 20 to 98 years) with applicable echocardiograms and no history of aortic disease or valve surgery were included. Aorta diameter was assessed at the annulus, sinus of Valsalva, sinotubular junction, and the tubular part of the ascending aorta. The study population comprised 1,796 men and 2,316 women; mean age: 56.4 ± 17.0 and 56.9 ± 18.1 years, respectively. Men had larger aortic root diameters than women regardless of height indexing (p <0.01). Age, height, weight, systolic and diastolic blood pressure, mean arterial pressure, pulse pressure, hypertension, diabetes, ischemic heart disease, and smoking were positively correlated with aortic sinus diameter in the crude and gender-adjusted analyses. However, after full adjustment, only height, weight, and diastolic blood pressure remained significantly positively correlated with aortic sinus diameter (p <0.001). For systolic blood pressure and pulse pressure, the correlation was inverse (p <0.001). During follow-up (median 5.4 [quartile 1 to quartile 3 4.5 to 6.3] years), the incidence rate of first-time acute aortic events was 13.6 (confidence interval 4.4 to 42.2) per 100,000 person-years. In conclusion, beyond anthropometric measures, age, and gender, diastolic blood pressure was the only cardiac risk factor that was independently correlated with aortic root dimensions. The number of aortic events during follow-up was low.

Imaging of giant cell arteritis - recent advances

Imaging is increasingly being used to guide clinical decision-making in patients with giant cell arteritis (GCA). While ultrasound has been rapidly adopted in fast-track clinics worldwide as an alternative to temporal artery biopsy for the diagnosis of cranial disease, whole-body PET/CT is emerging as a potential gold standard test for establishing large vessel involvement. However, many unanswered questions remain about the optimal approach to imaging in GCA. For example, it is uncertain how best to monitor disease activity, given there is frequent discordance between imaging findings and conventional disease activity measures, and imaging changes typically fail to resolve completely with treatment. This chapter addresses the current body of evidence for the use of imaging modalities in GCA across the spectrum of diagnosis, monitoring disease activity, and long-term surveillance for structural changes of aortic dilatation and aneurysm formation and provides suggestions for future research directions.