Biomechanical properties and histomorphometric features of aortic tissue in patients with or without bicuspid aortic valve.

BACKGROUND: We sought to investigate and compare biomechanical properties and histomorphometric findings of thoracic ascending aorta aneurysm (TAA) tissue from patients with bicuspid aortic valve (BAV) and tricuspid aortic valve (TAV) in order to clarify mechanisms underlying differences in the clinical course. METHODS: Circumferential sections of TAA tissue in patients with BAV (BAV-TAA) and TAV (TAV-TAA) were obtained during surgery and used for biomechanical tests and histomorphometrical analysis. RESULTS: In BAV-TAA, we observed biomechanical higher peak stress and lower Young modulus values compared with TAV-TAA wall. The right lateral longitudinal region seemed to be the most fragile zone of the TAA wall. Mechanical stress-induced rupture of BAV-TAA tissue was sudden and uniform in all aortic wall layers, whereas a gradual and progressive aortic wall breakage was described in TAV-TAA. Histomorphometric analysis revealed higher amount of collagen but not elastin in BAV-TAA tunica media. CONCLUSIONS: The higher deformability of BAV-TAA tissue supports the hypothesis that increased wall shear stress doesn't explain the increased risk of sudden onset of rupture and dissection; other mechanisms, likely related to alteration of specific genetic pathways and epigenetic signals, could be investigated to explain differences in aortic dissection and rupture in BAV patients.

The effect of preoperative respiratory physiotherapy and motor exercise in patients undergoing elective cardiac surgery: short-term results.

INTRODUCTION: Loss of physical activity and pulmonary dysfunction with its associated complications represent two of the most important causes of morbidity and mortality following cardiac surgery. Few studies have investigated the effects of preoperative interventions targeted at improving cardiorespiratory and musculoskeletal function in the postoperative period. AIM: To evaluate whether a physiotherapy program based on respiratory training with or without musculoskeletal mobilization, started preoperatively, may provide a significant improvement in pulmonary and musculoskeletal recovery postoperatively in patients undergoing elective cardiac surgery. MATERIAL AND METHODS: Patients with similar baseline and preoperative characteristics were randomly assigned to a preoperative respiratory physiotherapy protocol (group A), a preoperative respiratory and motor physiotherapy protocol (group B), or no preoperative specific physiotherapy protocol but only a simplified perioperative standard physiotherapy protocol (control group or group C). Group A consisted of 19 patients, group B of 20, group C of 20. Data on 6-minute walking test, peak expiratory flow, and from blood gas analysis were retrospectively analyzed. RESULTS: As compared with group C, a statistically significant improvement was observed in the two preoperatively treated groups A and B in terms of longer pre- and postoperative distance traveled at the 6-minute walking test, better pre- and postoperative peak expiratory flow value, and better PaO2 and SaO2 values in postoperative blood gas measurements (p < 0.05, for all comparisons). A statistically significant reduction of the postoperative length of in-hospital stay was also observed in group B. CONCLUSIONS: As compared with the control group, substantially better clinical results for respiratory and musculoskeletal function were found in the groups preoperatively treated with physiotherapeutic protocols immediately before as well as after cardiac surgery.

Clinical outcome and hemodynamic performance of St. Jude Trifecta aortic prosthesis: short-term follow-up and risk factors analysis.

BACKGROUND: We retrospectively analysed the short-term outcome of the third-generation St. Jude Trifecta aortic prosthesis. METHODS: Between December 2014 and December 2017, 177 patients (mean age 75.1±6.8 years, 95 males, 82 females) underwent aortic valve replacement with a St. Jude Trifecta aortic prosthesis and were followed up to 27±9 months. Preoperatively 92 patients (52.0%) were in NYHA class III-IV, EuroSCORE II was 3.2%±2.1%. RESULTS: Trifecta sizes implanted were 19 mm (n=46) (26%), 21 mm (n=69) (39%), 23 mm (n=46) (26%), 25 mm (n=16) (9%). Concomitant coronary artery bypass grafting was performed in 60 patients (34.0%). Operative mortality was 3.4% (1.7% for isolated aortic valve replacement versus 6.7% for combined aortic valve replacement and coronary artery bypass grafting) (P=0.084). The only independent predictor of mortality was the need for the mechanical ventilation greater than 24 hours (P=0.037); recently occurring myocardial infarction was risk factor for mortality at the univariate analysis only (P=0.013). Three-year survival was 84%±6%, freedom from cardiac death 98%±1%, freedom from prosthetic endocarditis 97%±1%. No thromboembolisms or structural valve degeneration were observed. Patient-prosthesis mismatch (PPM) was absent in 126 patients (71.2%), mild-to-moderate in 32 (18.1%), moderate in 19 (10.7%), severe in no any patient. Follow-up echocardiography showed an average mean and peak trans-aortic valve gradients reduction more than 70% in comparison with preoperative value (P<0.0001), and a significant regression of left ventricular hypertrophy (P<0.0001). Moderate PPM did not negatively affect survival. Concomitant severe coronary artery disease was found as an independent predictor of reduced survival (72%±12% versus 86%±6%) (P=0.015). CONCLUSIONS: Trifecta aortic prosthesis seems to provide very favourable clinical outcome and hemodynamic performance. At three years, survival was negatively affected by severe coronary artery disease detected at the time of operation. During short-term follow-up, no early structural valve degeneration was been observed. Due to low incidence of PPM and low peak and mean trans-prosthetic aortic valve gradients, third generation Trifecta aortic prosthesis should be considered as one of the best options in the setting of the aortic valve replacement surgery. However, a long-term follow-up is mandatory to confirm the early promising data.

Early structural degeneration of Mitroflow aortic valve: another issue in addition to the mismatch?

We reported two cases of early structural valve degeneration (SVD) with Mitroflow prosthesis in aortic position in patients above the age of 65 years. Microscopic aspects have been analysed to investigate the intrinsic mechanism of SVD. New techniques to improve the structure and the preservation of this prosthesis are needed in order to reduce potential dangerous early complications.

Coronary endarterectomy: an old tool for patients currently operated on with coronary artery bypass grafting. Long-term results, risk factor analysis.

AIM: Coronary endarterectomy (CE) may provide a useful adjunctive technique to coronary artery bypass grafting (CABG) in patients with diffuse coronary artery disease. Nevertheless, the incidence of complications still remains high, long-term results remain unclear, and no risk factors for late mortality have been completely described yet. MATERIAL AND METHODS: We retrospectively reviewed 90 consecutive patients (67 ±8.2 years) undergoing isolated CABG in association with CE between 2006 and 2013. Mean follow-up was 75.1 ±36.2 months (median: 84 months) and it was 100% complete (6755/6755 patient-months). RESULTS: Operative mortality was 4.4%, the incidence of perioperative myocardial infarction was 11%. Ten-year survival was 83.3 ±4.1%, freedom from cardiac death 92.7 ±2.9%, and freedom from major adverse cardiac and cerebrovascular events 58.2 ±10.2%. Independent predictors of late mortality were age older than 70 years at time of the surgery (p = 0.018) and chronic obstructive pulmonary disease (p = 0.036). Ten-year freedom from cardiac death was better after CE on the left descending coronary artery (LAD) (93.2 ±3.3%) in comparison to CE not on the LAD (74.6 ±10.2%), although this difference did not reach statistical significance (p = 0.102). CONCLUSIONS: Although the incidence of perioperative myocardial infarction continues to be not negligible, in the presence of diffusely diseased coronary artery vessels CE associated with CABG appears to be a feasible adjunctive surgical tool, conferring satisfactory early and long-term outcomes. Coronary endarterectomy on the LAD confers a high probability of freedom from late cardiac death. Patients older than 70 years and those affected by a primary respiratory disease represent a new challenge on which to focus attention due to the increased risk of late death.

Radiologic and Intraoperative Finding of Intimal Tear in Type A Intramural Hematoma of the Aorta.

Aortic intramural hematoma (IMH) is described as "dissection without intimal tear" due to rhexis of vasa vasorum, which results in bleeding within the tunica media in the absence of intimal disruption or blood flow communication. The aim of our study is to validate perioperative evidence of intimal entry tear in IMH patients and to suggest that this entity may represent a part of a disease and not a separate disease.