Early aortic growth in acute descending aortic dissection.

OBJECTIVES: Acute aortic dissection leads to the destabilization of the aortic wall, followed by an immediate increase in aortic diameter. It remains unclear how the aortic diameter changes during the dissection's acute and subacute phases. The aim of this study was to evaluate the change in aortic geometry within 30 days after the onset of a descending aortic dissection. METHODS: Patients with acute type B and non-A non-B dissection who had at least 2 computed tomography angiography scans obtained within 30 days after the onset of dissection were evaluated. Exclusion criteria were a thrombosed false lumen, connective tissue disorders and endovascular or open aortic repair performed prior to the second computed tomography angiography. RESULTS: Among 190 patients with acute aortic dissection, 42 patients met our inclusion criteria. Their aortic geometry was analysed according to the computed tomography angiography scans obtained between 0-3 (N = 35), 4-7 (N = 9) and 8-30 (N = 12) days after the dissection onset. The highest aortic diameter growth rate was observed in the first quartile of the thoracic aorta and measured 0.66 (0.06; 1.03), 0.29 (-0.01; 0.41) and 0.06 (-0.13; 0.26) mm/day at 0-3, 4-7 and 8-30 days after the dissection, respectively. Proximal entry location (P = 0.037) and entry located at the arch concavity (P = 0.008) were associated with a higher aortic diameter increase. CONCLUSIONS: Early rapid growth occurs during the first week after the descending aortic dissection-most intensely over the first 3 days, and this is associated with the location of the dissection's entry.

Bicuspid aortic valve repair with external or subcommissural annuloplasty-echocardiographic prospective trial.

BACKGROUND: The incompetent bicuspid aortic valve (BAV) can be repaired using various techniques. This study presents a prospective comparison of external and subcommissural aortic annuloplasty. METHODS: Fifty consecutive patients (38 males, age: 43.9 ± 15.8 years) with BAV insufficiency with or without aortic dilatation underwent valve repair in a single institution. They were prospectively allocated to one of two groups based on the aortic annulus stabilization technique: 25 patients were operated on using the subcommissural annuloplasty (SCA) and 25 using the external complete annuloplasty (EA). Transthoracic echocardiography was performed in all patients before the operation and 1 and 3 years after the operation. Moreover, mortality and morbidity at 7 years were evaluated. RESULTS: In prospective echocardiographic comparison, EA was associated with smaller diameter of the aortic annulus (24.1 ± 2.6 mm vs. 25.8±2.1 mm, p < .05) and lower mean and peak transvalvular gradients (7 ± 4 mmHg vs. 13 ± 4 mmHg, p = .02 and 15.3 ± 9.7 mmHg vs. 20.7 ± 5.6 mmHg, p = .03, respectively). No patients died or required reoperation due to recurrent insufficiency at 6,81 (interquartile range-0,17) years after the operation. The Kaplan-Meier actuarial freedom from aortic regurgitation (AR) grade =2 or gradient > 20 mmHg at 35.1 ± 3.6 months years was 96% (24 out of 25) for patients who had external annuloplasty and amounted to 76% (19 out of 25) for those who had SCA, p = .05). CONCLUSIONS: External annuloplasty performed during repair of the BAV is associated with better hemodynamics at medium-term follow-up compared to SCA.

Intraoperative postinfarct ventricular septal rupture during coronary bypass grafting.

We report a case of a ventricular septal rupture (VSR) which occurred during coronary artery bypass grafting (CABG) operation. The procedure took place 5 days after ST-elevation myocardial infarction of the inferior wall. The VSR repair was not performed at the time of the CABG operation. The intention was to wait until scar formation occurs to facilitate the repair. The patient was supported with venoarterial extracorporeal membranous oxygenation (VA-ECMO) and additional intra-aortic balloon pump (IABP) on intensive care unit. Ten days after CABG the patient underwent a successful VSR repair and 5 days later was weaned from VA-ECMO. He was discharged from hospital 6 weeks after the initial CABG. This case report underlines the importance of VA-ECMO and a multidisciplinary approach with frequent examination of haemodynamic state in the treatment of patients with mechanical complications of myocardial infarction who are not suitable for immediate repair.

Application of strain and other echocardiographic parameters in the evaluation of early and long-term clinical outcomes after cardiac surgery revascularization.

BACKGROUND: Coronary artery bypass graft (CABG) surgery is an effective therapeutic strategy for coronary heart disease (CHD). Myocardial longitudinal strain echocardiography with 2D speckle tracking could obtain ventricular function with better accuracy and reliability than the left ventricular ejection fraction. The aim of the study was to assess changes in left ventricular function in patients before and after surgical revascularization for a 24-month period of observation, using echocardiography with speckle tracking strain imaging. We searched for echocardiographic predictors of poor early and long-term outcome after CABG. METHODS: We enrolled 69 patients scheduled for elective coronary bypass grafting. Patients were divided into groups based on pre-operative systolic and diastolic parameters, depending on the GLS value and the E' Lat and E/E' value. The correlation between these parameters and early and long-term outcomes was analyzed. RESULTS: Preoperative EF was preserved in 86, 95% (60) patients. Pre-operative reduced GLS was observed in 73.91% (51) of patients and severely reduced in 31.88% (22). In the first post-operative 6-month period, we observed a significant decrease in the GLS. The GLS was a predictor of early postoperative outcome for intubation time, the inotropes use and length of ICU stay. Diastolic dysfunction was a predictor of the greater inotrope requirements. CONCLUSIONS: Global longitudinal strain and diastolic dysfunction parameters are a good predictors of worse early outcome after CABG.

Modelling of predissection aortic size in acute descending aortic dissection.

OBJECTIVES: Large aortic diameter is considered the most frequent cause of aortic dissection. However, this assumption relies on postdissection imaging of the aorta. We recently showed that acute dissection leads to a 23% increase in the descending aortic diameter. Our aim was to model the diameter of the aorta before the acute descending aortic dissection occurred. METHODS: Between 2003 and 2017, a total of 190 patients developed acute descending aortic dissection. In total, 165 non-Marfan patients were included, whose computed tomography angiography scans were available and taken within 6 h after the occurrence of acute descending aortic dissection [67 (first quartile 58-third quartile 75) years, 69% males]. The maximum postdissection aortic diameter was measured at the level of the mid-descending aorta. Modelling was performed by dividing the postdissection aortic diameter by the factor 1.23. RESULTS: The median modelled predissection descending diameter measured in the mid-descending aorta was 30.5 (27.3-35.4) mm. The median predissection descending diameter was higher in men (P = 0.021) and associated with age (P < 0.001) but not with body surface area. The modelled diameter of the predissected descending aorta revealed that 98.8% (163/165) of patients had an aortic diameter measuring <55 mm and 84.8% (140/165) <40 mm. In other words, 50% of these patients had a non-dilated descending aorta prior to dissection onset. CONCLUSIONS: Modelling indicated that more than 80% of patients who suffered an acute descending aortic dissection had a descending aorta <40 mm before dissection onset. Only 1% of them would have met the guideline criteria (aortic diameter ≥55 mm) for elective descending aortic repair. The role of an excessively large aortic diameter as a predictor of descending aortic dissection might be overrated.

A comparison of aortic root measurements by echocardiography and computed tomography.

OBJECTIVES: The aim of the study is to evaluate an optimal way to assess the dimensions of the aortic root and each of the sinuses of Valsalva and examine how a single measurement in 1 plane (echocardiography or 2-dimensional computed tomography) can underestimate the maximum dimension of the aortic root. METHODS: Computed tomography and transthoracic echocardiography images of the aortic root and ascending aorta of 112 patients were analyzed. The minimum and maximum aortic root dimensions, the root perimeter, and the total area of all 3 sinuses of Valsalva were measured on a plane perpendicular to the long axis of the aorta using 3-dimensional multiplanar reconstruction. Moreover, the maximum root dimension was compared with the measurements obtained from the echocardiography and 2-dimensional computed tomography angiography measurements. RESULTS: The difference in the measurements of the minimum and maximum root dimension was 5.4 ± 3.2 mm (range, 0-21 mm, P < .0001) and was significantly larger in patients with bicuspid aortic valves compared with those with tricuspid valves (6.3 ± 4 mm, range, 0-21 mm vs 4.9 ± 2.6 mm, range, 0-15 mm, P = .036). The maximum root dimension measured in 3-dimensional multiplanar reconstruction (49.1 ± 9.0 mm) differed significantly from the root dimension measured in transthoracic echocardiography in the parasternal long-axis view (44.8 ± 8.4 mm) and 2-dimensional computed tomography (axial plane: 45.5 ± 9.0 mm, coronal plane: 46.1 ± 8.8 mm, sagittal plane: 45.1 ± 8.9 mm) (P < .001). CONCLUSIONS: The difference in the measurements of the minimum and maximum aortic root dimensions is significant and may exceed 20 mm, especially in patients with bicuspid aortic valves. Therefore, aortic root dimensions can be significantly underestimated with the measurement (echocardiography, computed tomography angiography) performed in only 1 plane.

In Vitro Evaluation of Aortic Stent Graft Deployment Accuracy in the Distal Landing Zone.

OBJECTIVES: Thoracic endovascular aortic repair technology focuses on accurately deploying the stent graft in the proximal landing zone in the proximal to distal direction. The aim of this in vitro study was to evaluate the accuracy of stent graft deployment in the distal landing zone. METHODS: It was hypothesised that a reverse implantation mechanism (in a distal to proximal deployment direction, when the operator starts to open the endoprosthesis from distal to proximal), might enhance landing accuracy in the distal LZ. The aim was to investigate this hypothesis by implanting stent grafts into the 3D printed aortas with the currently available deployment mechanism. Based on two human patients' computed tomography angiography scans, two aortas were 3D printed at 1:1 scale: "straight" and "crooked" aortas with distal aortic tortuosity of 1.006 and 1.078, respectively. They were used in order to test three endoprostheses (E-vita THORACIC 3G, Relay Plus, Valiant Captivia) 10 times by implanting them in three ways: proximal landing in the aneurysm, proximal landing in another stent graft, reverse implantation (via simulated antegrade access). The aim was to land just above the target vessel's upper edge. The distance to the target vessel and wedge apposition were assessed under a direct view using caliper. RESULTS: The distance to the target vessel was 3 mm (IQR 0; 8) if the stent graft landed proximally in aneurysm, 2 mm (IQR 0; 5) if it landed proximally in another stent graft, and 0 mm (IQR 0; 0) when reverse implantation was applied. The distance to the target vessel measuring 5 mm or occurred in 45%, 30%, and 0%, respectively. Overall the median wedge apposition after stent graft implantation was 0 mm (IQR 0; 0) in the "straight" versus 18 mm (IQR 15; 20) in the "crooked" aorta (p < .001). CONCLUSIONS: Reverse stent graft deployment is associated with more accurate landing in the distal landing zone. Distal aortic tortuosity constitutes an important impediment to covering the distal LZ's entire circumference with a stent graft.

Wall stress correlates with intimal entry tear localization in Type A aortic dissection.

OBJECTIVES: The risk of aortic dissection should be assessed based not only on the aortic diameter, but also on other biomechanical parameters that have an impact on the stress in the aortic wall. This study evaluates very rare clinical scenarios of patients with both pre- and post-dissection computed tomography (CT) images and evaluates whether an increased wall stress correlates with the localization of an intimal entry tear in Type A aortic dissection. METHODS: CT-angiography images of 4 patients performed shortly prior to and after developing Type A aortic dissection were evaluated. The stress distribution in the pre-dissection aortas was evaluated using the finite elements method. Then, the areas of high stress in the pre-dissection aortas were compared to the localization of the intimal entry tears in the dissected vessels. RESULTS: In all the patients, the pre-dissection areas of high wall stress correlated with the location of the intimal tears. The highest stress was not observed in the most dilated segments of the aorta but was predominantly found in the areas of an abrupt change in the geometry of the aorta. CONCLUSIONS: Wall stress can indicate the areas susceptible to the formation of an intimal tear and subsequent aortic dissection. Stress analysis may be a valuable tool to predict the risk of aortic dissection in patients with aortic dilatation.

Inaccurate aortic stent graft deployment in the distal landing zone: incidence, reasons and consequences.

OBJECTIVES: The aim of this study was to investigate the accuracy of stent graft deployment in the distal landing zone (LZ) during thoracic endovascular aortic repair (TEVAR). Currently, TEVAR focuses on accurate stent graft deployment in the proximal LZ. Data on landing in the distal LZ are lacking. METHODS: Of 195 TEVAR patients (2005-16) with a non-dissected aortic pathology, 59 [median age 73 years (first quartile 68; third quartile 77), 20 women] patients had a distal LZ shorter than 40 mm. In all, the aim was to deploy the stent graft just above the target vessel (coeliac trunk, mesenteric superior or renal artery). Patients were divided into the accurate landing (n = 10) and inaccurate landing (IAL, n = 49) groups according to the distance to the target vessel ≤ 5 mm or > 5 mm after TEVAR, target vessel coverage and the need for a second stent graft in the distal LZ. We assessed the distal LZ, stent graft distance to the target vessel, apposition, migration and endoleak Ib on computed tomography. Median follow-up period was 23 months (5; 48). RESULTS: Distal LZ anatomy did not differ between groups. Overall stent graft distance to the target vessel was 10.0 mm (6.5 mm; 16.0 mm). Three patients required a second stent graft in the distal LZ, and in 3 others, the target vessel was accidentally covered. In patients of the accurate landing group primary endoleak Ib occurred less frequently than those in the IAL group (0% vs 33%; P = 0.049). Three (30%) accurate landing and 19 (39%) IAL patients (P = 0.73) presented with substantial stent graft wedge apposition. CONCLUSIONS: Accurate stent graft implantation in the distal LZ with the currently available deployment mechanism is often challenging. An inaccurate landing is associated with a higher incidence of endoleak Ib.

Fate of the dissected aortic arch after ascending replacement in type A aortic dissection†.

OBJECTIVES: To evaluate the fate of a dissected aortic arch after limited surgical repair of type A aortic dissection. METHODS: Of the 271 patients operated for acute type A dissection between 2001 and 2015, 86 (age 57 ± 13 years, 74% men) with predischarge computed tomographic (CT) scans had a residual dissection in the arch. Aortic diameters, lengths, ellipticity and communications between lumina were assessed using predischarge and follow-up CT scans. The median CT scan follow-up was 31 months (first quartile 15, third quartile 52). RESULTS: The largest increase in the total aortic diameter at follow-up was 20 mm distal to the left subclavian artery (median +4.0 mm; first quartile +1.5, third quartile +9.2 mm; P = 0.004), with an average growth rate of 1.5 mm/year (first quartile 0.6, third quartile 3.9 mm). The true lumen diameter was unchanged at follow-up. At least 1 communication between the true and the false lumina was observed in 80% of patients on the predischarge CT scan, and 70% had communications at the distal aorta-graft anastomosis. Accelerated increase in the diameter of the dissected aorta was associated with the number of communications between the lumina, communication at the distal anastomosis and false lumen perfusion (all, P < 0.001). CONCLUSIONS: Dissection of the residual aortic arch leads to aortic growth that may result in an aneurysm requiring treatment. The number of communications between the lumina, communication at the distal anastomosis and false lumen perfusion are associated with the accelerated aortic growth. Endovascular repair may be difficult due to the small true lumen and the presence of many communications between the lumina.

Role of vascular endothelial growth factor in inducing production of angiopoetin-1 - in vivo study in Fisher rats.

The aim of the study was to investigate how an intramuscular injection of plasmids with genes coding various pro-angiogenic factors: angiopoetin-1 (ANGPT1), vascular endothelial growth factor (VEGF165) and hepatic growth factor (HGF), influences the production of ANGPT1. 40 Healthy Fisher rats received i.m. injections containing plasmids encoding pro-angiogenic genes in thigh muscles. They were divided into four equal groups. The first group received the plANGPT1 plasmid and the second group- the pIRES/ANGPT1/VEGF165 bicistronic plasmid. The pIRES/VEGF165/HGF bicistronic plasmid was administered to the third group and an empty plasmid (control group) to the fourth group. The animals were euthanized after 12 weeks. In each group, the number of vessels stained with the anti-ANGPT1 antibody was assessed under an optical microscope. The anti-ANGPT1 antibodies stained the vessels in all the groups. There were on average 14.1 ±2.3 vessels in the the plANGPT1 group, 32.5 ±10.5 in the pl/RESANGPT1/VEGF group and 30.8 ±13.3 in the plRES/HGV/VEGF group. There were on average 7.3 ±2.3 stained vessels (p < 0.0001) in the control group . The VEGF plays a role in the induction of the production of ANGPT1. The administration of plasmids only encoding ANGPT1 does not induce its production.

The Formation of Blood Vessel After the Administration of the Plasmid Encoding Ang-1 Gene in Fischer Rats.

BACKGROUND: Chronic limb ischemia is a serious clinical problem. Patients who do not qualify for standard treatment may benefit from novel gene therapies. OBJECTIVES: This study evaluated angiogenesis following intramuscular injections of angiogenic plasmid Ang-1 in Fisher rats. MATERIAL AND METHODS: Twenty rats had plasmids injected intramuscularly in their hind limbs. The study group consisted of 10 animals which received the Ang-1 plasmid, while the control group consisted of 10 rats that received an empty plasmid. All the animals were euthanized after 12 weeks and tissue samples from the hind limb thigh muscles and internal organs were harvested for histological and immunohistochemical examinations. To assess the angiogenesis the number of vessels in the hind limb muscles visualized by the SMA and FVIII markers was counted for each animal in five separate microscopic fields. RESULTS: There were no pathological lesions or any signs of neoplastic angiogenesis in any of the 20 rats. The number of vessels visualized by the FVIII marker in the study group was two times higher than in the control group (median: 12, range: 7-25 vs. median: 6, range: 2-15; p < 0.0001). The median estimated that the number of vessels visualized by the SMA marker is 63% higher in the study group compared to the control group (median: 6.5, range: 1-12 vs. median: 4, range: 0-10; p = 0.0008). CONCLUSIONS: Intramuscular injections of Ang-1 plasmids induced angiogenesis in the rat hind limb muscles.

Computed tomography angiography of aorta subjected to external wrapping.

BACKGROUND: External wrapping is a surgical technique used in patients with dilated ascending aorta. To date, there is no available data describing the radiographic features of the aorta subjected to external wrapping using a straight corrugated Dacron vascular prosthesis. The aim of this study was to find distinctive radiographic features of an externally constricted aorta. METHODS: Preoperative and early postoperative (7th postoperative day) CT angiography images of ten patients who underwent wrapping procedures were assessed and compared. The images were analyzed in order to find characteristic features of CT angiography images of the ascending aorta subjected to external wrapping. RESULTS: The CT-angiography images showed that the aortic wall deformed significantly (the wall plicated) after the wrapping procedure in one patient, whose aortic diameter was decreased by 47 %. The remaining nine patients did not have significant aortic wall deformations. All patients presented with a periaortic mass. This was a collection of blood clots and pericardial fluid that filled the empty space in the pericardium following a decrease in the diameter of the ascending aorta. A very thin (<1 mm) crescent-shaped uncontrasted layer was noticed between the aorta and the periaortic area in all patients. This, in turn, was an empty space between the aorta and the corrugated vascular prosthesis. CONCLUSIONS: The CT-angiography images of the aorta subjected to external wrapping may have unique features that are not observed after other operations on the ascending aorta. The knowledge about the details of this surgical procedure helps to correctly assess these images.

Single center experience with wrapping of the dilated ascending aorta.

BACKGROUND: External wrapping is a surgical technique performed in patients with a dilated ascending aorta. The aim of this study is to present the mid-term results of wrapping of the dilated ascending aorta. METHODS: 34 patients (mean age: 64.4 ± 10.8 years, 21 males) with a dilated ascending aorta were operated on at a single cardiac surgery center using a wrapping technique. The aortas were wrapped with 32-36 mm straight Dacron vascular prostheses. The aortic wall was not excised in any of the patients. Wrapping was performed concomitant to other cardiac surgery procedures in 30 patients (88 %), which involved surgery on the aortic valve in 28 patients (82 %). RESULTS: The mean follow-up time was 19.5 ± 8.3 months (median: 18 months, range: 12-36 months). None of the patients died or had aortic complications during the hospital stay and the follow-up period. A rethoracotomy had to be performed due to excessive postoperative bleeding in two patients. One patient was diagnosed with a transient ischemic attack on the 4th postoperative day, while another had respiratory failure requiring prolonged intubation. No redilatation of the ascending aorta or dislocation of the wrap was noticed in any of the patients. CONCLUSIONS: According to our study, external wrapping of the ascending aorta has good short-term results and may be regarded as a safe surgical option for patients with a moderately dilated ascending aorta.

Biomechanical analysis of wrapping of the moderately dilated ascending aorta.

BACKGROUND: External wrapping is a surgical method performed to prevent the dilatation of the aorta and to decrease the risk of its dissection and rupture. However, it is also believed to cause degeneration of the aortic wall. A biomechanical analysis was thus performed to assess the stress of the aortic wall subjected to external wrapping. METHODS: A stress analysis using the finite elements method was carried out on three models: a non-dilated aorta, a moderately dilated aorta and a wrapped aorta. The models were subjected to a pulsatile flow (120/80 mmHg) and a systolic aortic annulus motion of 11 mm. RESULTS: The finite elements analysis showed that the stress exerted on the outer surface of the ascending aorta in the wrapping model (0.05-0.8 MPa) was similar to that observed in the normal aorta (0.03-0.7 MPa) and was lower than in the model of a moderately dilated aorta (0.06-1.4 MPa). The stress on the inner surface of the ascending aorta ranged from 0.2 MPa to 0.4 MPa in the model of the normal aorta, from 0.3 to 1.3 MPa in the model of the dilated aorta and from 0.05 MPa to 0.4 MPa in the wrapping model. CONCLUSIONS: The results of this study suggest that the aortic wall is subjected to similar stress following a wrapping procedure to the one present in the normal aorta.

First beating-heart valve-sparing aortic root repair: a "corset" technique.

We present our preliminary experience with beating-heart aortic root remodeling using an external "corset," which we performed in 2 patients with aortic insufficiency and aortic root dilatation. Standard extracorporeal circulation (ECC) was used. After a meticulous dissection of the aortic root and ascending aorta, the bespoke vascular prosthesis was placed around the vessel to decrease its diameter and restore aortic valve function. Postoperative angiographic computed tomography (CT) showed a significant decrease in the diameter of the wrapped aorta. Echocardiography performed 12 months after the operation showed normal aortic valve function with trivial regurgitation and stable aortic diameter in both patients.

A meta analysis and systematic review of wrapping of the ascending aorta.

BACKGROUND: One of the methods of dealing with a dilated ascending aorta is to decrease its diameter using external wrapping. This exovascular procedure is regarded by many surgeons as controversial. The aim of the study was to evaluate the safety and efficacy of external wrapping of the ascending aorta. METHODS: A metaanalysis and systematic review of studies reporting mid-term and long-term results of wrapping of the ascending aorta were performed. The postoperative hospital mortality, aortic-related mortality, significant redilatation rate, and need for aortic reoperation were analyzed. RESULTS: 17 manuscripts were included in the final analysis and postoperative data of 722 patients were studied. The mean age of patients was 58 years and mean follow-up was 62 months. Hospital mortality was 1.5% (11 deaths). During the follow-up late aortic related mortality was noted in two patients (0.3%), there were 12 (1.7%) cases of significant redilatation of the ascending aorta, and 13 (1.8%) patients had to have their ascending aorta reoperated. All of the aortic complications were noted in patients who either did not have their external wrapping sutured to the aorta or who underwent concomitant aortoplasty. CONCLUSIONS: The results of the metaanalysis suggest that external aortic wrapping may be considered as a safe operative technique. In patients with a moderately dilated aorta it offers good mid-term and long-term outcome compared to replacement of the ascending aorta.