Background Data from the International Registry of Acute Aortic Dissection indicate that the guideline criterion of 5.5 cm for ascending aortic intervention misses many dissections occurring at smaller dimensions. Furthermore, studies of natural behavior have generally treated the aortic root and the ascending aorta as 1 unit despite embryological, anatomical, and functional differences. This study aims to disentangle the natural histories of the aforementioned aortic segments, allowing natural behavior to define specific intervention criteria for root and ascending segments of the aorta. Methods and Results Diameters of the aortic root and mid‐ascending segment were measured separately. Long‐term complications (dissection, rupture, and death) were analyzed retrospectively for 1162 patients with ascending thoracic aortic aneurysm. Cox regression analysis suggested that aortic root dilatation ( P =0.017) is more significant in predicting adverse events than mid‐ascending aortic dilatation ( P =0.087). Short stature posed as a serious risk factor. The dedicated risk curves for the aortic root and the mid‐ascending aorta revealed hinge points at 5.0 and 5.25 cm, respectively. Conclusions The natural histories of the aortic root and mid‐ascending aorta are uniquely different. Dilation of the aortic root imparts a significant higher risk of adverse events. A diameter shift for intervention to 5.0 cm for the aortic root and to 5.25 cm for the mid‐ascending aorta should be considered at expert centers.

Heart failure can be treated with devices that mechanically support the circulation. The improvement of these devices would benefit many patients, especially those refractory to maximal pharmacological treatment and ineligible for heart transplantation. This study examined whether the shape memory alloy (SMA) fibers, which are fibers that contract when electric current flows through them and relax passively when that flow is interrupted, can be wrapped around the failing heart and assist in its pumping action. A band of SMA fibers was wrapped around a silicon cylindrical chamber which simulated a dilated heart and its pumping action was tested in a circulatory mockup. This rudimentary device was innovatively controlled by pulse width modulation. The band was made of only six fibers but yet produced the considerable pressure of 20 mm Hg and a stroke volume of 11.8 ml with modest energy demands. A SMA device could assist a severely failing heart, but there are limiting factors to overcome before designing highly effective devices.

Pericoronary adipose tissue (PCAT) is a source of microRNAs (miRs) that act as messengers for intercellular communication. We investigated whether the PCAT surrounding significant coronary atherosclerotic lesions shows specific miR expression patterns compared with PCAT surrounding plaque-free segments. We included 49 patients with 3-vessel coronary artery disease (CAD) and 19 patients with severe valvular disease but no CAD, who underwent elective cardiac surgery. The PCAT was harvested from two sites: adjacent to a significant atherosclerotic coronary lesion and from plaque-free segments. miR-133a, miR-21, miR-26b, miR-9, and miR-143 levels in PCAT cells were quantified by real-time reverse transcription polymerase chain reaction (data expressed as arbitrary units). Expression of miR-133, miR-21, and miR-26b in adipose tissue at a site without atherosclerotic lesion was much lower in patients with CAD than in those without CAD (0.82 ± 1.37 vs 1.86 ± 0.52, P < .001, 0.45 ± 1.3 vs 1.51 ± 1.11, P < .001, 0.3 ± 1.25 vs 1.2 ± 0.73, P = .02, respectively). In addition, miR-133, miR-21, and miR-143 in CAD patients showed significantly greater expression in PCAT from atherosclerotic lesion compared with plaque-free segments (1.32 ± 0.96 vs 0.82 ± 0.37 (P = .011), 0.91 ± 1.7 vs 0.3 ± 1.25 (P = .012), 1.2 ± 1.59 vs 0.43 ± 0.54 (P < .001), respectively). Our findings open new perspectives for the role of PCAT in the pathophysiology of atherosclerosis and should be further investigated.

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