Features and outcomes of female and male patients requiring postcardiotomy extracorporeal life support.

OBJECTIVES: Although cardiogenic shock requiring extracorporeal life support after cardiac surgery is associated with high mortality, the impact of sex on outcomes of postcardiotomy extracorporeal life support remains unclear with conflicting results in the literature. We compare patient characteristics, in-hospital outcomes, and overall survival between females and males requiring postcardiotomy extracorporeal life support. METHODS: This retrospective, multicenter (34 centers), observational study included adults requiring postcardiotomy extracorporeal life support between 2000 and 2020. Preoperative, procedural, and extracorporeal life support characteristics, complications, and survival were compared between females and males. Association between sex and in-hospital survival was investigated through mixed Cox proportional hazard models. RESULTS: This analysis included 1823 patients (female: 40.8%; median age: 66.0 years [interquartile range, 56.2-73.0 years]). Females underwent more mitral valve surgery (females: 38.4%, males: 33.1%, P = .019) and tricuspid valve surgery (feamales: 18%, males: 12.4%, P < .001), whereas males underwent more coronary artery surgery (females: 45.9%, males: 52.4%, P = .007). Extracorporeal life support implantation was more common intraoperatively in feamales (females: 64.1%, females: 59.1%) and postoperatively in males (females: 35.9%, males: 40.9%, P = .036). Ventricular unloading (females: 25.1%, males: 36.2%, P < .001) and intra-aortic balloon pumps (females: 25.8%, males: 36.8%, P < .001) were most frequently used in males. Females had more postoperative right ventricular failure (females: 24.1%, males: 19.1%, P = .016) and limb ischemia (females: 12.3%, males: 8.8%, P = .23). In-hospital mortality was 64.9% in females and 61.9% in males (P = .199) with no differences in 5-year survival (females: 20%, 95% CI, 17-23; males: 24%, 95% CI, 21-28; P = .069). Crude hazard ratio for in-hospital mortality in females was 1.12 (95% CI, 0.99-1.27; P = .069) and did not change after adjustments. CONCLUSIONS: This study demonstrates that female and male patients requiring postcardiotomy extracorporeal life support have different preoperative and extracorporeal life support characteristics, as well as complications, without a statistical difference in in-hospital and 5-year survivals.

Predicting late aortic complications after acute type A dissection surgery with volumetric measurements in a Singapore cohort.

Introduction: This study was conducted to evaluate the efficacy of postoperative computed tomography (CT) measurements of aortic lumen volumes in predicting aortic-related complications following acute type A aortic dissection (ATAAD) repair. Methods: We conducted a single-institution retrospective aortic volumetric analysis of patients after ascending aorta replacement performed during 2001-2015. The volumetric measurements of total lumen (total-L), true lumen (TL), false lumen (FL), as well as the TL:FL ratio from the first and second postoperative computer angiograms were obtained. A generalised structural equation model was created to analyse the predictive utility of TL:FL ratio. Results: One hundred and twenty-five patients underwent surgical intervention, of whom 97 patients were eventually discharged and analysed for postoperative complications. A total of 19 patients were included in the final analysis. Patients with late postoperative aortic complications had a significantly higher FL volume and total-L volume on the first (FL volume P = 0.041, total-L volume P = 0.05) and second (FL volume P = 0.01, total-L volume P = 0.007) postoperative scans. The odds of having aortic complications were raised by 1% with a 1 cm3 increase in total-L volume and by 2% with a 1 cm3 increase in FL volume. The TL:FL ratio was significantly lower in patients who developed complications. Conclusion: Postoperative CT volumetric measurements in patients who developed complications are characterised by a significant increase in the FL volume and total-L volume from the first postoperative scans. Patients with disproportionately expanded FL presenting with TL:FL ratios less than 1 were associated with aortic complications. Hence, the TL:FL ratio may be a reliable and useful parameter to monitor postoperative disease progression and to evaluate the risk of late complications in ATAAD patients.

The Relation Between Obesity and Mortality in Postcardiotomy Venoarterial Membrane Oxygenation.

BACKGROUND: Obesity is an important health problem in cardiac surgery and among patients requiring postcardiotomy venoarterial extracorporeal membrane oxygenation (V-A ECMO). Still, whether these patients are at risk for unfavorable outcomes after postcardiotomy V-A ECMO remains unclear. The current study evaluated the association between body mass index (BMI) and in-hospital outcomes in this setting. METHODS: The Post-cardiotomy Extracorporeal Life Support (PELS-1) study is an international, multicenter study. Patients requiring postcardiotomy V-A ECMO in 36 centers from 16 countries between 2000 and 2020 were included. Patients were divided in 6 BMI categories (underweight, normal weight, overweight, class I, class II, and class III obesity) according to international recommendations. Primary outcome was in-hospital mortality, and secondary outcomes included major adverse events. Mixed logistic regression models were applied to evaluate associations between BMI and mortality. RESULTS: The study cohort included 2046 patients (median age, 65 years; 838 women [41.0%]). In-hospital mortality was 60.3%, without statistically significant differences among BMI classes for in-hospital mortality (P = .225) or major adverse events (P = .126). The crude association between BMI and in-hospital mortality was not statistically significant after adjustment for comorbidities and intraoperative variables (class I: odds ratio [OR], 1.21; 95% CI, 0.88-1.65; class II: OR, 1.45; 95% CI, 0.86-2.45; class III: OR, 1.43; 95% CI, 0.62-3.33), which was confirmed in multiple sensitivity analyses. CONCLUSIONS: BMI is not associated to in-hospital outcomes after adjustment for confounders in patients undergoing postcardiotomy V-A ECMO. Therefore, BMI itself should not be incorporated in the risk stratification for postcardiotomy V-A ECMO.

Aging-induced isoDGR-modified fibronectin activates monocytic and endothelial cells to promote atherosclerosis.

BACKGROUND AND AIMS: Aging is the primary risk factor for cardiovascular disease (CVD), but the mechanisms underlying age-linked atherosclerosis remain unclear. We previously observed that long-lived vascular matrix proteins can acquire 'gain-of-function' isoDGR motifs that might play a role in atherosclerotic pathology. METHODS: IsoDGR-specific mAb were generated and used for ELISA-based measurement of motif levels in plasma samples from patients with coronary artery diseases (CAD) and non-CAD controls. Functional consequences of isoDGR accumulation in age-damaged fibronectin were determined by bioassay for capacity to activate monocytes, macrophages, and endothelial cells (signalling activity, pro-inflammatory cytokine expression, and recruitment/adhesion potential). Mice deficient in the isoDGR repair enzyme PCMT1 were used to assess motif distribution and macrophage localisation in vivo. RESULTS: IsoDGR-modified fibronectin and fibrinogen levels in patient plasma were significantly enhanced in CAD and further associated with smoking status. Functional assays demonstrated that isoDGR-modified fibronectin activated both monocytes and macrophages via integrin receptor 'outside in' signalling, triggering an ERK:AP-1 cascade and expression of pro-inflammatory cytokines MCP-1 and TNFα to drive additional recruitment of circulating leukocytes. IsoDGR-modified fibronectin also induced endothelial cell expression of integrin ß1 to further enhance cellular adhesion and matrix deposition. Analysis of murine aortic tissues confirmed accumulation of isoDGR-modified proteins co-localised with CD68+ macrophages in vivo. CONCLUSIONS: Age-damaged fibronectin features isoDGR motifs that increase binding to integrins on the surface of monocytes, macrophages, and endothelial cells. Subsequent activation of 'outside-in' signalling elicits a range of potent cytokines and chemokines that drive additional leukocyte recruitment to the developing atherosclerotic matrix.

Left heart bypass versus circulatory arrest for open repair of thoracoabdominal aortic pathologies.

BACKGROUND: Most large-volume centres use left heart bypass (LHB) as their preferred organ protection strategy during repair of descending thoracic aortic (DTA) and thoracoabdominal aortic (TAA) pathologies. We investigate the use of hypothermic circulatory arrest (HCA) for similar pathologies and compare the outcomes of both. METHODS: A PubMed, Embase and Scopus search for studies in English on LHB versus HCA for repair of DTA and TAA pathologies published from inception till February 2020 was performed. Our analysis excluded studies without direct comparison of the two organ protection strategies. Clinical endpoints that were studied were 30-day mortality, post-operative stroke, spinal cord deficit, renal failure and respiratory failure. Random effects meta-analyses of the effect of the two strategies across all clinical endpoints were conducted. RESULTS: HCA is non-inferior to LHB across all clinical endpoints. In terms of 30-day mortality (odds ratio (OR) 1.19, 95% confidence interval (CI) 0.31-4.59, P = 0.14, I2 = 49%), stroke (OR 0.41, 95% CI 0.12-1.39, P = 0.97, I2 = 0%), spinal cord deficit (OR 0.56, 95% CI 0.22-1.45, P = 0.78, I2 = 0%), renal failure (OR 1.33, 95% CI 0.37-4.76, P = 0.98, I2 = 0%) and respiratory failure (OR 0.86, 95% CI 0.37-1.97, P = 0.16, I2 = 46%), there was no statistically significant difference between the two cohorts. CONCLUSION: Evidence is limited, but suggests that HCA alone provides adequate organ protection during repair of DTA and TAA pathologies, and has equivalent outcomes when compared to LHB.

Sleep apnoea and cardiovascular outcomes after coronary artery bypass grafting.

OBJECTIVE: Patients with advanced coronary artery disease are referred for coronary artery bypass grafting (CABG) and it remains unknown if sleep apnoea is a risk marker. We evaluated the association between sleep apnoea and major adverse cardiac and cerebrovascular events (MACCE) in patients undergoing non-emergent CABG. METHODS: This was a prospective cohort study conducted between November 2013 and December 2018. Patients from four public hospitals referred to a tertiary cardiac centre for non-emergent CABG were recruited for an overnight sleep study using a wrist-worn Watch-PAT 200 device prior to CABG. RESULTS: Among the 1007 patients who completed the study, sleep apnoea (defined as apnoea-hypopnoea index ≥15 events per hour) was diagnosed in 513 patients (50.9%). Over a mean follow-up period of 2.1 years, 124 patients experienced the four-component MACCE (2-year cumulative incidence estimate, 11.3%). There was a total of 33 cardiac deaths (2.5%), 42 non-fatal myocardial infarctions (3.7%), 50 non-fatal strokes (4.9%) and 36 unplanned revascularisations (3.2%). The crude incidence of MACCE was higher in the sleep apnoea group than the non-sleep apnoea group (2-year estimate, 14.7% vs 7.8%; p=0.002). Sleep apnoea predicted the incidence of MACCE in unadjusted Cox regression analysis (HR 1.69; 95% CI 1.18 to 2.43), and remained statistically significant (adjusted HR 1.57; 95% CI 1.09 to 2.25), after adjustment for age, sex, body mass index, left ventricular ejection fraction, diabetes mellitus, hypertension, chronic kidney disease and excessive daytime sleepiness. CONCLUSION: Sleep apnoea is independently associated with increased MACCE in patients undergoing CABG. TRIAL REGISTRATION NUMBER: NCT02701504.

Mid-term single-center outcomes of BioIntegral compared to Freestyle aortic conduit implantation.

BACKGROUND: Full aortic root replacement with biological conduit has limited options. This non-randomized cohort study aims to compare mid-term clinical and hemodynamic results of the BioIntegral (BI) composite biological versus the stentless Freestyle (FS) conduits in patients undergoing full aortic root replacement. METHODS: From February 2013 to July 2017, 265 patients underwent aortic root replacement at a single institution (202 BI, 65 FS). Preoperative, intraoperative and postoperative parameters, complications including stroke, myocardial infarction (MI), endocarditis and reoperation were studied. Hemodynamic performance of both conduits was analyzed by echocardiography. Target endpoints were 30-day mortality, two-year survival, two-year freedom from major adverse valve-related and cardiovascular events. RESULTS: Wider BI conduits were used (BI 27±2 vs. FS 25±2 mm, P<0.0001). The BI group had shorter cardiopulmonary bypass (BI 165±67 vs. FS 200±78 min, P<0.0001) and cross-clamp (BI 102±36 vs. FS 122±40 min, P=0.001) times. Thirty-day mortality was similar in both groups. There were fewer conduit-related reoperations in the BI group (BI 0% vs. FS 3%, P=0.012) but higher postoperative atrial fibrillation (BI 31% vs. FS 17%, P=0.025). No significant differences were observed for stroke (BI 5% vs. FS 10%, P=0.947), MI (BI 3% vs. FS 4%, P=0.583), or infective endocarditis (BI 0% vs. FS 2%, P=0.077). No significant hemodynamic differences were evident on follow-up echocardiography while an improved overall survival trend was seen in the BI group (P=0.062). CONCLUSIONS: FS and BI provide comparable clinical mid-term results and hemodynamic parameters. Simplified implantation technique providing shorter cardiopulmonary bypass and operation times are advantageous for BI.

Coronary artery bypass grafting in patients with low ejection fraction: what are the risk factors?

BACKGROUND: Left ventricular (LV) dysfunction alone is insufficient as an independent predictor of postoperative complications and mortality in coronary artery bypass graft (CABG) surgery. Our objective was to identify additional independent risk factors in patients with low left ventricle ejection fraction (EF) who underwent CABG. METHODS: We retrospectively analyzed CABG results of 346 consecutive patients with low EF (≤30%) in a single institution between 2009 and 2015. The primary study endpoint was 30-day all-cause mortality. The secondary endpoints were the development of major adverse cardiac events (MACE) and renal complications after operation. A subgroup of patients underwent additional analyses of the interaction between extents of viable myocardium and postoperative endpoints. RESULTS: The analysis showed that preoperative hemodynamic instability (AOR=4.57; 95% CI: 1.53-13.7, P=0.007) and serum creatinine >166 µmol/L (AOR=3.46; 95% CI: 1.12-10.7, P=0.031) were independent predictors of 30-day death. Both urgent and emergency operations were predictors for MACE (P=0.038; P=0.005) and renal complications (P=0.004; P=0.007). Pre-existing diabetes mellitus increased the likelihood of renal complications (P=0.020). In the sub-analysis of patients with viable myocardium, the mortality was significantly lower with predicted mortality (P=0.014). CONCLUSIONS: Patients with significant LV dysfunction undergoing isolated CABG have fair short-term survival even with EF less than 30%. Hemodynamic instability prior to operation and preoperative kidney dysfunction are strong predictors of mortality in patients with low EF. Favorable coronary targets, meticulous operative techniques, and optimal surgical timing before hemodynamic deterioration occurs are essential to minimize the risk of revascularization complications and early postoperative mortality.

Plasma Ceramides as Prognostic Biomarkers and Their Arterial and Myocardial Tissue Correlates in Acute Myocardial Infarction.

We identified a plasma signature of 11 C14 to C26 ceramides and 1 C16 dihydroceramide predictive of major adverse cardiovascular events in patients with acute myocardial infarction (AMI). Among patients undergoing coronary artery bypass surgery, those with recent AMI, compared with those without recent AMI, showed a significant increase in 5 of the signature's 12 ceramides in plasma but not simultaneously-biopsied aortic tissue. In contrast, a rat AMI model, compared with sham control, showed a significant increase in myocardial concentrations of all 12 ceramides and up-regulation of 3 ceramide-producing enzymes, suggesting ischemic myocardium as a possible source of this ceramide signature.

Gene expression profile analysis of aortic vascular smooth muscle cells reveals upregulation of cadherin genes in myocardial infarction patients.

Myocardial infarction (MI) induced by acute coronary arterial occlusion is usually secondary to atherosclerotic plaque rupture. Dysregulated response of vascular smooth muscle cells (VSMCs) in atherosclerotic plaques may promote plaque rupture. Cadherins (CDHs) form adherens junctions and are known stabilizers of atherosclerotic plaques. To date, the expression patterns of cadherin have not been well investigated in MI aortic VSMCs. We aimed to investigate the expression of cadherin genes in the aortic wall of patients with and without MI. Laser capture microdissected VSMCs were obtained from aortic tissue samples of patients undergoing coronary artery bypass graft surgery. Integrative bioinformatic analysis of the microarray profiles of the VSMCs revealed that MI is discriminated at the whole transcriptome level by hundreds of differentially expressed genes, including genes involved in cell adhesion, of which the cadherin superfamily genes were among the top structural category. Eleven significantly deregulated candidates of the cadherin superfamily were chosen and formed a new classifier that collectively discriminated MI vs. non-MI with ~95% accuracy. Significance validation was performed with an independent cohort by quantitative RT-quantitative PCR, confirming overexpression of CDH2, CDH12, PCDH17, and PCDH18 in MI VSMCs. The dysregulation of these cadherin superfamily genes might be related to an MI-induced remote effect on aortic wall VSMCs and to imbalances in signaling pathways and myocardial repair mechanisms. Although pathophysiological significance of our findings requires functional studies, mRNA upregulation of the identified cadherin superfamily members in VSMCs might be associated with the progression of atherosclerosis and angiogenesis activation in MI.

Distinctive molecular signature and activated signaling pathways in aortic smooth muscle cells of patients with myocardial infarction.

BACKGROUND AND AIMS: We aim to identify significant transcriptome alterations of vascular smooth muscle cells (VSMCs) in the aortic wall of myocardial infarction (MI) patients. Providing a robust transcriptomic signature, we aim to highlight the most likely aberrant pathway(s) in MI VSMCs. METHODS AND RESULTS: Laser-captured microdissection (LCM) was used to obtain VSMCs from aortic wall tissues harvested during coronary artery bypass surgery. Microarray gene analysis was applied to analyse VSMCs from 17 MI and 19 non-MI patients. Prediction Analysis of Microarray (PAM) identified 370 genes that significantly discriminated MI and non-MI samples and were enriched in genes responsible for muscle development, differentiation and phenotype regulation. Incorporation of gene ontology (GO) led to the identification of a 21-gene VSMCs-associated classifier that discriminated between MI and non-MI patients with 92% accuracy. The mass spectrometry-based iTRAQ analysis of the MI and non-MI samples revealed 94 proteins significantly differentiating these tissues. Ingenuity Pathway Analysis (IPA) of 370 genes revealed top pathways associated with hypoxia signaling in the cardiovascular system. Enrichment analysis of these proteins suggested an activation of the superoxide radical degradation pathway. An integrated transcriptome-proteome pathway analysis revealed that superoxide radical degradation pathway remained the most implicated pathway. The intersection of the top candidate molecules from the transcriptome and proteome highlighted superoxide dismutase (SOD1) overexpression. CONCLUSIONS: We provided a novel 21-gene VSMCs-associated MI classifier in reference to significant VSMCs transcriptome alterations that, in combination with proteomics data, suggests the activation of superoxide radical degradation pathway in VSMCs of MI patients.

Coronary and arch hybrid surgery in a patient with infrarenal aortic occlusion.

A 65-year-old gentleman with claudication underwent contrast-enhanced computed tomography. The scan showed occlusion of the infrarenal abdominal aorta and a 6.0 × 3.7 cm saccular zone-3 arch aneurysm. The left ventricular ejection fraction was 35% and a coronary angiogram revealed triple-vessel disease. In view of the patient's high risk with EuroSCORE II 20.34%, coronary artery surgery was combined with hybrid type I arch aneurysm repair. An endovascular stent was delivered in an antegrade manner. Open heart surgery and a hybrid type I arch intervention can be performed simultaneously through a midline sternotomy approach.

Aortic Wall Extracellular Matrix Proteins Correlate with Syntax Score in Patients Undergoing Coronary Artery Bypass Surgery.

AIMS: The SYNTAX score correlate with major cardiovascular events post-revascularization, although the histopathological basis is unclear. We aim to evaluate the association between syntax score and extracellular matrix histological characteristics of aortic punch tissue obtained during coronary artery bypass surgery (CABG). This analysis compares coronary artery bypass surgery patients with High and Low syntax score which were followed up for one year period. METHODS AND RESULTS: Patients with High (score ≥ 33, (n=77)) and Low Syntax Scores (score ≤ 22, (n=71)) undergoing elective CABG were recruited prospectively. Baseline clinical characteristics and surgical risks were well matched. At 1 year, EMACCE (Sum of cardiovascular death, stroke, congestive cardiac failure, and limb, gut and myocardial ischemia) was significantly elevated in the High syntax group (P=0.022). Mass spectrometry (MS)-based quantitative iTRAQ proteomic results validated on independent cohort by immunohistochemistry (IHC) revealed that the High syntax group had significantly upraised Collagen I (P<0.0001) and Elastin (P<0.0001) content in ascending aortic wall. CONCLUSION: This study shows that aortic extracellular matrix (ECM) differ between High and Low syntax groups with up-regulation of Collagen I and Elastin level in High Syntax Score group. This identifies aortic punches collected during CABG as another biomarker source related with atherosclerosis severity and possible clinical outcome.

Differential MicroRNA Expression Profile in Myxomatous Mitral Valve Prolapse and Fibroelastic Deficiency Valves.

Myxomatous mitral valve prolapse (MMVP) and fibroelastic deficiency (FED) are two common variants of degenerative mitral valve disease (DMVD), which is a leading cause of mitral regurgitation worldwide. While pathohistological studies have revealed differences in extracellular matrix content in MMVP and FED, the molecular mechanisms underlying these two disease entities remain to be elucidated. By using surgically removed valvular specimens from MMVP and FED patients that were categorized on the basis of echocardiographic, clinical and operative findings, a cluster of microRNAs that expressed differentially were identified. The expressions of has-miR-500, -3174, -17, -1193, -646, -1273e, -4298, -203, -505, and -939 showed significant differences between MMVP and FED after applying Bonferroni correction (p < 0.002174). The possible involvement of microRNAs in the pathogenesis of DMVD were further suggested by the presences of in silico predicted target sites on a number of genes reported to be involved in extracellular matrix homeostasis and marker genes for cellular composition of mitral valves, including decorin (DCN), aggrecan (ACAN), fibromodulin (FMOD), α actin 2 (ACTA2), extracellular matrix protein 2 (ECM2), desmin (DES), endothelial cell specific molecule 1 (ESM1), and platelet/ endothelial cell adhesion molecule 1 (PECAM1), as well as inverse correlations of selected microRNA and mRNA expression in MMVP and FED groups. Our results provide evidence that distinct molecular mechanisms underlie MMVP and FED. Moreover, the microRNAs identified may be targets for the future development of diagnostic biomarkers and therapeutics.

Comparison of different surgical techniques in 112 consecutive patients with aortic root operations: when should the valve be spared?

BACKGROUND AND AIM OF THE STUDY: The benefit of valve-sparing aortic root replacement compared to conventional aortic root replacement surgery remains unclear. METHODS: Between February 2009 and November 2010, a total of 112 patients underwent aortic root surgery at the Department of Cardiovascular and Thoracic Surgery, Heinrich-Heine-University, Dusseldorf, Germany. The valve-sparing technique was used when leaflets were grossly normal. In cases where the valve could not be saved, a prosthetic or biological substitute was used for the aortic root, according to existing guidelines. The patients were allocated to three groups: (i) valve-sparing aortic root replacement group using the David technique (VSR-David; n = 47); (ii) valve-replacing aortic root surgery with a prosthetic conduit using the Bentall-Kuchucus technique (VRR-Prosthetic; n = 31); and (iii) valve-replacing aortic root surgery with a biological stentless valve with the full root technique (VRR-Bio; n = 34). RESULTS: Intraoperative data revealed that, in the VSR-David group, the cardiopulmonary bypass and cross-clamp times were significantly longer (207 +/- 68 min and 140 +/- 38 min respectively; both p = 0.001). The VRR-Prosthetic patients were at highest risk (mean EuroSCORE 15.9%) compared to the VSR-David and VRR-Bio groups (10.8% and 10.4%, respectively). Postoperative analysis showed that patients in the VRR-Bio group had the lowest number of perioperative heart failures (p = 0.004). The perioperative 30-day mortality was significantly higher in the VRR-Prosthetic group (22.6%; p = 0.004). Transaortic flow velocities were significantly lower in the VSR-David group, followed by the VRR-Bio group and VRR-Prosthetic group (1.66 +/- 0.54, 1.98 +/- 0.45, and 2.29 +/- 0.39 m/s, respectively; p = 0.012). The univariate and multivariate analyses of perioperative risk factors showed that only open distal anastomosis was strongly associated with negative results, but not the valve-sparing technique. CONCLUSION: Aortic valve-sparing root replacement must be considered as an excellent alternative for young patients requiring aortic root replacement when a biological valve is clinically indicated. For patients aged >65 years, or with a decreased life expectancy, the full root technique with a stentless valve should be used, given its technical simplicity and excellent postoperative results.

Resolution of ascending aortic dissection in a Stanford type A patient.

We observed an unusual natural course of a Stanford type A aortic dissection. The patient presented to the emergency department with an acute aortic dissection involving an ascending aorta and left-sided hemiparesis. The patient declined surgery and was managed conservatively. A follow-up scan after 1 month revealed that the patient had a complete spontaneous resolution of the dissection in the ascending aorta. Such a development is very rare and unexpected in patients with Stanford type A aortic dissection.

Characteristics of aortic wall extracellular matrix in patients with acute myocardial infarction: tissue microarray detection of collagen I, collagen III and elastin levels.

OBJECTIVES: Extracellular matrix (ECM) remodelling of the vessel wall is hypothesized to be an important step in atherosclerosis. Changes of the ECM are associated with the gradual progression of an atherosclerotic lesion from a lipid streak to complicated unstable plaque, leading to a complete vessel occlusion and eventually myocardial infarction (MI). Understanding of this process is critical in the treatment and prevention of ischaemic heart disease (IHD). METHODS: We investigated the histopathological characteristics of aortic wall ECM in IHD patients. Collagen I, collagen III and elastin were assessed immunohistochemically in patients with acute MI and those with stable angina, using aortic punch tissues obtained from coronary artery bypass graft surgery. Fluorescence tissue images were analysed using the tissue microarray technique. RESULTS: The results showed that collagen III expression was found to be significantly lower in the acute MI group (P < 0.001). As a result of this change, the patients with MI also revealed a significant reduction in the collagen III/collagen I ratio. The elastin/collagen III ratio was significantly higher in the MI group (P < 0.001). CONCLUSIONS: Our study provided evidence of a decrease in collagen III content in patients with MI, which could possibly explain the mechanism of plaque vulnerability and weakening of the plaque cap. A reduction in collagen III content, particularly away from the atherosclerotic lesions, might be explained by the systemic vascular changes in patients with MI, and inflammation and immune responses could be potential causes of these systemic transformations. The biochemical mechanisms and factors regulating collagen III production might be potential markers to predict possible cardiovascular events.

Consequences of incomplete repair of acute type A aortic dissection.

During emergency repair of acute Stanford type A aortic dissections, surgical compromises in the form of incomplete arch replacement are made due to the unstable condition of the patient and safety issues of the performing team. We report a case of delayed reoperation after previous incomplete surgery for acute type A aortic dissection in a young patient with Marfan's syndrome. He presented again with repetitive chest pain five years after initial surgical treatment. Extensive aneurysmal dilatation of the aorta and remaining dissection led to the decision to replace the ascending aorta and the aortic arch. After a good progress during the first days after surgery, the patient died due to a ruptured thoraco-abdominal aneurysm on the fifth postoperative day. Extensive surgical reconstruction including aortic arch replacement should be considered in patients with Marfan's syndrome who present with aortic dissections type A to avoid unnecessary reoperations and their complications.