Morphology of the Left Atrial Appendage: Introduction of a New Simplified Shape-Based Classification System

BACKGROUND

The left atrial appendage (LAA) is a heart structure with known prothrombogenic and pro-arrhythmogenic properties.

AIM

The aim of this study was to evaluate the specific anatomy of the LAA and to create a simple classification system based on the shape of its body.

METHOD AND RESULTS

This study investigated 200 randomly selected autopsied human hearts (25.0% females, 46.6±19.1 years old). Three (3) types of LAAs were distinguished: the cauliflower type (no bend, limited overall length, compact structure [36.5%]); the chicken wing type (substantial bend in the dominant lobe [37.5%]), and the arrowhead type (no bend, one dominant lobe of substantial length [26.0%]). Additional accessory lobes were present in 55.5% of all LAAs. Significant variations between category types were noted in LAA length (chicken wing: 35.7±9.8 mm, arrowhead: 30.8±10.1 mm, cauliflower: 22.3±9.6 mm [p<0.001]) and in the thickness of pectinate muscles located within the LAA apex (arrowhead: 1.2±0.7 mm; cauliflower: 1.1±0.6 mm; chicken wing: 0.9±0.6 mm [p<0.001]). Left atrial appendage volume and orifice size were not affected by the type of LAA shape. The age of the donor was positively correlated with LAA volume (r=0.29, p=0.005), body length (r=0.26, p=0.012), and area of the orifice (r=0.36, p<0.001). Donors with an oval LAA orifice were significantly older than those with round orifices (50.2±16.6 vs 43.7±20.4 years [p=0.014]) and had significantly heavier hearts (458.2±104.8 vs 409.6±114.1g [p=0.002]).

CONCLUSIONS

This study delivered a new simple classification system of the LAA based on its body shape. An increase in age and heart weight was associated with LAA enlargement and a more oval-shaped orifice. Results of current study may help to estimate the different thrombogenic properties associated with each LAA type and be an assistance during planning and performing interventions on LAA.

Topographical anatomy of the right atrial appendage vestibule and its isthmuses

INTRODUCTION

The right atrial appendage (RAA) vestibule is an area located in the right atrium between the RAA orifice and the right atrioventricular valve annulus and may be a target for invasive transcatheter procedures.

METHODS AND RESULTS

We examined 200 autopsied human hearts. Three isthmuses (an inferior, a middle, and a superior isthmus) were detected. The average length of the vestibule was 67.4 ± 10.1 mm. Crevices and diverticula were observed within the vestibule in 15.3% of specimens. The isthmuses had varying heights: superior: 14.0 ± 3.4 mm, middle: 11.2 ± 3.1 mm, and inferior: 10.1 ± 2.7 mm (p < .001). The superior isthmus had the thickest atrial wall (at midlevel: 16.7 ± 5.6 mm), the middle isthmus had the second thickest wall (13.5 ± 4.2 mm), and the inferior isthmus had the thinnest wall (9.3 ± 3.0 mm; p < .001). This same pattern was observed when analyzing the thickness of the adipose layer (superior isthmus had a thickness of 15.4 ± 5.6 mm, middle: 11.7 ± 4.1 mm and inferior: 7.1 ± 3.1 mm; p < .001). The average myocardial thickness did not vary between isthmuses (superior isthmus: 1.3 ± 0.5 mm, middle isthmus: 1.8 ± 0.8 mm, inferior isthmus: 1.6 ± 0.5 mm; p > .05). Within each isthmus, there were variations in the thickness of the entire atrial wall and of the adipose layer. These were thickest near the valve annulus and thinnest near the RAA orifice (p < .001). The thickness of the myocardial layer followed an inverse trend (p < .001).

CONCLUSIONS

This study was the first to describe the detailed topographical anatomy of the RAA vestibule and that of its adjoining isthmuses. The substantial variability in the structure and dimensions of the RAA isthmuses may play a role in planning interventions within this anatomic region.

Myocardial proteomic profile in pulmonary arterial hypertension

Pulmonary arterial hypertension (PAH) is a rare, fatal, and incurable disorder. Although advances in the understanding of the PAH pathobiology have been seen in recent years, molecular processes underlying heart remodelling over the course of PAH are still insufficiently understood. Therefore, the aim of this study was to investigate myocardial proteomic profile of rats at different stages of monocrotaline-induced PAH. Samples of left and right ventricle (LV and RV) free wall collected from 32 Wistar rats were subjected to proteomic analysis using an isobaric tag for relative quantitation method. Hemodynamic parameters indicated development of mild elevation of pulmonary artery pressure in the early PAH group (27.00 ± 4.93 mmHg) and severe elevation in the end-stage PAH group (50.50 ± 11.56 mmHg). In early PAH LV myocardium proteins that may be linked to an increase in inflammatory response, apoptosis, glycolytic process and decrease in myocardial structural proteins were differentially expressed compared to controls. During end-stage PAH an increase in proteins associated with apoptosis, fibrosis and cardiomyocyte Ca2+ currents as well as decrease in myocardial structural proteins were observed in LV. In RV during early PAH, especially proteins associated with myocardial structural components and fatty acid beta-oxidation pathway were upregulated. During end-stage PAH significant changes in RV proteins abundance related to the increased myocardial structural components, intensified fibrosis and glycolytic processes as well as decreased proteins related to cardiomyocyte Ca2+ currents were observed. At both PAH stages changes in RV proteins linked to apoptosis inhibition were observed. In conclusion, we identified changes of the levels of several proteins and thus of the metabolic pathways linked to the early and late remodelling of the left and right ventricle over the course of monocrotaline-induced PAH to delineate potential therapeutic targets for the treatment of this severe disease.

Identification of CD34+/PGDFRα+ Valve Interstitial Cells (VICs) in Human Aortic Valves: Association of Their Abundance, Morphology and Spatial Organization with Early Calcific Remodeling

Aortic valve interstitial cells (VICs) constitute a heterogeneous population involved in the maintenance of unique valvular architecture, ensuring proper hemodynamic function but also engaged in valve degeneration. Recently, cells similar to telocytes/interstitial Cajal-like cells described in various organs were found in heart valves. The aim of this study was to examine the density, distribution, and spatial organization of a VIC subset co-expressing CD34 and PDGFRα in normal aortic valves and to investigate if these cells are associated with the occurrence of early signs of valve calcific remodeling. We examined 28 human aortic valves obtained upon autopsy. General valve morphology and the early signs of degeneration were assessed histochemically. The studied VICs were identified by immunofluorescence (CD34, PDGFRα, vimentin), and their number in standardized parts and layers of the valves was evaluated. In order to show the complex three-dimensional structure of CD34+/PDGFRα+ VICs, whole-mount specimens were imaged by confocal microscopy, and subsequently rendered using the Imaris (Bitplane AG, Zürich, Switzerland) software. CD34+/PDGFRα+ VICs were found in all examined valves, showing significant differences in the number, distribution within valve tissue, spatial organization, and morphology (spherical/oval without projections; numerous short projections; long, branching, occasionally moniliform projections). Such a complex morphology was associated with the younger age of the subjects, and these VICs were more frequent in the spongiosa layer of the valve. Both the number and percentage of CD34+/PDGFRα+ VICs were inversely correlated with the age of the subjects. Valves with histochemical signs of early calcification contained a lower number of CD34+/PDGFRα+ cells. They were less numerous in proximal parts of the cusps, i.e., areas prone to calcification. The results suggest that normal aortic valves contain a subpopulation of CD34+/PDGFRα+ VICs, which might be involved in the maintenance of local microenvironment resisting to pathologic remodeling. Their reduced number in older age could limit the self-regenerative properties of the valve stroma.

Morphometric characteristics of myocardial sleeves of the pulmonary veins

BACKGROUND

The pulmonary veins are covered by a myocardial layer, which is often an electrical substrate for atrial fibrillation. The aim of this study was to study the morphologic characteristics of the myocardial sleeves of pulmonary veins by examining a large group of freshly autopsied human material.

METHODS AND RESULTS

The study macroscopically examined a total of 498 pulmonary veins draining the left atrium (120 unpreserved human hearts). In 75.0% of specimens, a classical pulmonary venous pattern was observed. The remainder of specimens either had an additional middle right pulmonary vein (20.0% of cases) or a common left pulmonary vein (5.0% of cases). Among all the veins seen in the classical pulmonary venous drainage type, the left superior pulmonary vein had the longest myocardial sleeves (9.4 ± 4.6 mm; coverage = 60.1 ± 19.4%), followed by the left inferior pulmonary vein (6.6 ± 3.5 mm; coverage = 47.6 ± 18.3%), the right superior pulmonary vein (6.0 ± 2.7 mm; coverage = 50.5 ± 13.9%) and then the right inferior pulmonary vein (5.0 ± 2.8 mm; coverage = 45.6 ± 16.2%; analysis of variance p < .001). In hearts with an additional right pulmonary vein, this vessel had the shortest myocardial sleeves (2.7 ± 1.1 mm; coverage = 36.0 ± 11.6%). In hearts with a common left pulmonary vein, the myocardial sleeves had the longest course for the common vein (13.7 ± 4.4 mm; coverage = 79.7 ± 4.9%).

CONCLUSIONS

Myocardial sleeves of the pulmonary veins were seen in each examined specimen, however, their length varied significantly. In hearts with a classical venous drainage pattern, the left superior pulmonary vein had the longest sleeves. When present, an additional middle right pulmonary vein had the shortest myocardial sleeves, while the left common pulmonary vein had the longest sleeves.

Changes in heart morphometric parameters over the course of a monocrotaline-induced pulmonary arterial hypertension rat model

Background

Aim of this study was to assess changes in cardiac morphometric parameters at different stages of pulmonary arterial hypertension (PAH) using a monocrotaline-induced rat model.

Methods

Four groups were distinguished: I–control, non-PAH (n = 18); II–early PAH (n = 12); III–end-stage PAH (n = 23); and IV–end-stage PAH with myocarditis (n = 7).

Results

Performed over the course of PAH in vivo echocardiography showed significant thickening of the right ventricle free wall (end-diastolic dimension), tricuspid annular plane systolic excursion reduction and decrease in pulmonary artery acceleration time normalized to cycle length. No differences in end-diastolic left ventricle free wall thickness measured in echocardiography was observed between groups. Significant increase of right ventricle and decrease of left ventricle systolic pressure was observed over the development of PAH. Thickening and weight increase (241.2% increase) of the right ventricle free wall and significant dilatation of the right ventricle was observed over the course of PAH (p < 0.001). Reduction in the left ventricle free wall thickness was also observed in end-stage PAH (p < 0.001). Significant trend in the left ventricle free wall weight decrease was observed over the course of PAH (p < 0.001, 24.3% reduction). Calculated right/left ventricle free wall weight ratio gradually increased over PAH stages (p < 0.001). The reduction of left ventricle diameter was observed in rats with end-stage PAH both with and without myocarditis (p < 0.001).

Conclusions

PAH leads to multidimensional changes in morphometric cardiac parameters. Right ventricle morphological and functional failure develop gradually from early stage of PAH, while left ventricle changes develop at the end stages of PAH.

Topography of the oblique vein of the left atrium (vein of Marshall)

BACKGROUND

The oblique vein of the left atrium is of interest for electrophysiologists working in the field of both basic science and clinical practice.

AIMS

We aimed to examine the topographic anatomy of the oblique vein and to assess the vein's location and relationships with surrounding cardiac structures.

METHODS

A total of 200 autopsied adult human hearts were examined.

RESULTS

The oblique vein was observed in 71% of the hearts. Its mean (SD) total length was 30.8 (13.6) mm. In hearts with the oblique vein, a larger distance was observed between the left inferior pulmonary vein (LIPV) and great cardiac vein (mean [SD], 18.6 [5.1] mm vs 16.3 [4.8] mm; P = 0.004), between the left atrial appendage (LAA) and LIPV (mean [SD], 17.8 [6.8] mm vs 15.1 [5.2] mm; P = 0.007), and between the LAA and left superior pulmonary vein (LSPV; mean [SD], 28.5 [7.2] mm vs 21.3 [6.4] mm; P <0.001). Hearts with a classic pattern of left‑sided pulmonary veins were categorized into 4 types based on the length of oblique vein extension. In type I, the vein extended below the level of the LIPV (21.9%); in type II, to the level of the LIPV (47.7%); in type III, to the level of the interpulmonary area (17.2%); and in type IV, to the level of the LSPV (13.3%). In each type, the distance between the oblique vein and LIPV was shorter than that between the oblique vein and LAA Conclusions: The oblique vein had a variable course and differing lengths of extension. The presence of the oblique vein was connected with a greater distance between the left‑sided pulmonary veins and LAA.

Morphometric Features of Patent Foramen Ovale as a Risk Factor of Cerebrovascular Accidents: A Systematic Review and Meta-Analysis

INTRODUCTION

It is still disputable whether specific morphometric features of the patent foramen ovale (PFO) may stratify patients by the related probability that a discovered PFO is incidental or stroke related.

OBJECTIVE

We aimed to determine whether certain morphometrical characteristics of PFO are associated with an increased risk of cerebrovascular accidents, using a meta-analytical approach.

METHODS

We performed a systematic review of electronic databases for studies that compared morphometric parameters of PFO assessed by transesophageal echocardiography (TEE) in subjects with cryptogenic cerebrovascular accidents (Group 1) and control (Group 2). Data were extracted and pooled into a meta-analysis.

RESULTS

A total of 895 patients with PFO were reported (Group 1: 493, Group 2: 402). No difference was found in the PFO channel length (Group 1: 10.8 [8.6-12.9] mm vs. Group 2: 10.4 [9.1-11.7] mm), as well as in PFO height measured at rest (Group 1: 2.4 [1.5-3.3] mm vs. Group 2: 1.8 [1.4-2.2] mm). The PFO height measured during a Valsalva maneuver was larger in Group 1 (3.5 [2.8-4.1] mm) than in Group 2 (1.7 [1.2-2.2] mm). Also, the septal excursion distance was found to be larger in Group 1 (6.4 [5.1-7.8] mm) than in Group 2 (3.1 [1.8-4.4] mm). The risk of cerebrovascular accident was higher in patients with PFO and concomitant septal aneurysm (OR 4.00; 95% CI 2.63-6.09; p < 0.001) and with large right-to-left shunt PFO (OR 3.81; 95% CI 2.21-6.55; p < 0.001), no such relationship was found for the presence of a Eustachian valve or Chiari's network (OR 1.90; 95% CI 0.90-4.05; p = 0.094).

CONCLUSIONS

The TEE may help in identifying PFO that are of high risk of cerebrovascular accident. Greater PFO height during a Valsalva maneuver, larger septal excursion distance, concomitant atrial septal aneurysm, and large right-to-left shunt are associated with stroke-related PFOs.

Right Atrioventricular Valve Leaflet Morphology Redefined: Implications for Transcatheter Repair Procedures

OBJECTIVES

The authors aimed to comprehensively detail the right atrioventricular valve functional leaflet anatomies.

BACKGROUND

The rapid development of both surgical and percutaneous repair techniques for tricuspid regurgitation has renewed interest in variations in the morphology of the right atrioventricular valve.

METHODS

The functioning right atrioventricular valves of 40 reanimated human hearts were imaged using Visible Heart methodologies. Hearts were then perfusion-fixed and dissected, uniquely allowing for the comparative assessments of functional versus fixed valve anatomies from the same set of donor hearts.

RESULTS

The right atrioventricular valves have "3-leaflet" configurations in 57.5% and "4-leaflet" configurations in the remaining hearts. For 4-leaflet valves, extra leaflets were commonly observed in the most inferior regions of the annuli. No difference in valve perimeters between 2 valve types were observed (112.2 vs. 117.1 mm; p = 0.14). In 3-leaflet valves, septal, mural, and superior leaflets occupied 32.2 ± 6.5%, 15.9 ± 5.5%, and 25.5 ± 6.2% of the annulus, respectively, whereas in the 4-leaflet arrangements, these values were 27.0 ± 5.8% (septal), 12.0 ± 4.5% (inferior), 13.7 ± 9.4% (mural), and 19.8 ± 6.1% (superior). The muroseptal/inferoseptal commissures were usually located in the cavotricuspid regions, whereas the inferomural and superomural commissures were in the right atrial appendage vestibule area.

CONCLUSIONS

The right atrioventricular valve has 4 functional leaflets in more than 40% of cases. The authors found that the inferomural region is the most variable area of the valve and believe that anatomic variation is an important consideration for planned interventions.

The influence of bariatric surgery on serum levels of irisin and nesfatin-1

Introduction: Bariatric surgery is associated with multiple endocrine and metabolic changes. Irisin and nesfatin-1 have recently been described as regulatory peptides involved in obesity-related insulin resistance. Our aim was to analyze the changes of those two molecules observed in patients after bariatric procedures. Materials and methods: This prospective study involved 40 patients treated for morbid obesity. Irisin and nesfatin-1 were measured before, 6 months and 1 year after surgical intervention. We also gathered demographic data, information concerning comorbidities, factors related to the surgery and outcomes of bariatric treatment. Results: Twenty-seven patients completed the study (15 females). The mean age of the group was 43.5 ± 10.4 years. Six (22.2%) patients were submitted to Laparoscopic Sleeve Gastrectomy and 21 (77.8%) patients were submitted to Laparoscopic Roux-en-Y Gastric Bypass. The participants in our study achieved significant weight loss. The irisin level remained stable in the whole study group during all three measurements included in our study protocol (p = .71). Our study group presented a reduction of the nesfatin-1 level 6 months after bariatric surgery and a slight further decrease after one-year observation, although these changes were also not significant (p = .17). Conclusions: We did not find any significant correlation between changes of irisin or nesfatin-1 level and bariatric surgery, as an aid in the regulation of glucose metabolism.

Topographic characteristics of the left atrial medial isthmus

BACKGROUND

The purpose of this study was to provide detailed topography of the left atrial medial isthmus (situated between the right inferior pulmonary vein ostium and the medial part of the mitral annulus).

METHODS

Two hundred human hearts (Caucasian, 22.5% females, 48.7 ± 4.9 years old) were investigated.

RESULTS

The mean length of the medial isthmus was 42.4 ± 8.6 mm. Additionally, the medial isthmus line was divided by the oval fossa into three sections with equal mean lengths (upper: 14.2 ± 7.2 vs middle: 14.1 ± 6.1 vs lower: 14.9 ± 4.6 mm; P > .05). The left upper section of the atrial wall was thinner than the lower section (2.5 ± 1.1 vs 3.4 ± 1.6 mm; P < .0001). This study noted three separate spatial arrangements of the isthmus line. Type I (54.5%) had an oval fossa located outside the isthmus line; type II (32.5%) had an oval fossa crossed by the isthmus line, and type III (13.0%) had an oval fossa rim located tangentially to the isthmus line. In 68.5% of the examined specimens, the isthmus area had a smooth surface. Conversely, the remaining 31.5% had additional structures within its borders such as diverticula, recesses, and tissue bridges.

CONCLUSION

This study is the first to describe the morphometric and topographical features of the left atrial medial isthmus. Interventions within the medial isthmus line should be performed cautiously, especially when they are transected by the oval fossa (32.5%). Careful navigation of the area is also recommended due to the possibility of existent additional structures. The latter could lead to catheter entrapment during ablation procedures.

Variations and morphometric features of the vermiform appendix: A systematic review and meta-analysis of 114,080 subjects with clinical implications

Determining the true and indisputable data regarding the vermiform appendix (VA) morphology is of a great clinical interest. The aim of this study was to provide the best evidence-based anatomical overview of the variations in location and size of VA using a systematic and meta-analytical approach. A systematic review with meta-analysis was performed of studies reporting variants of the location and morphometric data regarding the VA. The MEDLINE/PubMed, ScienceDirect, EMBASE, BIOSIS, SciELO, and Web of Science databases were thoroughly searched throughout June 2018. The reported locations of the body of the VA were re-classified into a new, standardized classification system divided into nine categories. The AQUA tool was used to assess the quality of included studies. The research was conducted following PRISMA guidelines and registered at PROPSERO database. Our meta-analysis included 242 studies (n = 114,080). Overall, the VA was most commonly found in the retrocecal location (32.1%, 95%CI: 29.2-35.1), followed by the pelvic (28.5%, 95%CI: 26.7-30.4) and ileal (14.5%, 95%CI: 11.8-17.7) locations. Subjects without known appendiceal pathologies had significantly smaller VA outer diameters (5.84 mm, 95%CI: 5.68-5.99) than patients diagnosed with acute appendicitis (10.64 mm, 95%CI: 10.14-11.15). The overall pooled mean length of the VA was 80.29 mm (95%CI: 76.68-83.89). Significant differences were found in size of the VA between imaging modalities. The results obtained from this evidence-based anatomy study will improve the clinical understanding of the VA anatomy, which in turn will have major implications for clinical practice. Clin. Anat. 32:85-98, 2019. © 2019 Wiley Periodicals, Inc.

Evaluation of Local Tissue Reaction After the Application of a 3D Printed Novel Holdfast Device for Left Atrial Appendage Exclusion

The left atrial appendage (LAA) is a small, finger-like extension of the left atrium and its exclusion is used as a treatment strategy to prevent ischemic stroke. Existing holdfast devices may damage the tissue, are unisized and not adjustable. A novel holdfast device for LAA exclusion devoid of these shortcomings was designed and 3D-printed using the Selective Laser Sintering (SLS) technology with polyamide powder and tested it on animal model. We selected the SLS 3D printing technology due to its wid14e availability and low production costs which could provide on-site 3D printing for specific patient. The purpose of this study was to evaluate the biocompatibility of the reported holdfast device and compare the histological results obtained for local tissue reactions to those obtained for an established grafting material. Thirty swine subdivided into two groups were examined. The LAA exclusion device was implanted and was either coated with a polyester vascular implant or not coated at all and the histological response to the device’s presence was evaluated which is a standard approach to test the device biocompatibility. In all cases, complete occlusion was seen without any pathological findings during the incubation time. In both groups, the surface of the atrium under a holdfast device was smooth and shiny and had no clots. The foreign body reaction of the LAA holdfast device made of polyamide powder was insignificantly lower compared to the polyester graft. Thus, it fulfils the parameters of biocompatibility at the highest degree, and makes it suitable material for the manufacturing of LAA holdfast devices.

Fixative properties of honey solutions as a formaldehyde substitute in cardiac tissue preservation

OBJECTIVES

To evaluate the properties of natural sweetener solutions in whole organ preservation and assess their influence on the dimension, weight and shape of cardiac tissue samples in stated time intervals, up to a one-year period of observation.

BACKGROUND

Tissue fixation is essential for biological sample examination. Many negative toxic effects of formaldehyde-based fixatives have forced us to seek alternatives for formaldehyde based solutions. It has been demonstrated that natural sweeteners can preserve small tissue samples well and that these solutions can be used in histopathological processes. However, their ability to preserve whole human organs are unknown.

METHODS

A total of 30 swine hearts were investigated. Three study groups (n = 10 in each case) were formed and classified on the type of fixative: (1) 10% formaldehyde phosphate-buffered solution (FPBS), (2) 10% alcohol-based honey solution (ABHS), (3) 10% water-based honey solution (WBHS). Samples were measured before fixation and in the following time points: 24 hours, 72 hours, 168 hours, 3 months, 6 months and 12 months.

RESULTS

The WBHS failed to preserve heart samples and decomposition of tissues was observed one week after fixation. In half of the studied parameters, the ABHS had similar modifying tendencies as compared to FPBS. e overall condition of preserved tissue, weight, left ventricular wall thickness, right ventricular wall thickness and the diameter of the papillary muscle differed considerably.

CONCLUSIONS

The ABHS may be used as an alternative fixative for macroscopic studies of cardiac tissue, whereas the WBHS is not suited for tissue preservation.

Morphological variations of the interatrial septum in ovine heart

Smooth septum interatrial septum, patent foramen ovale (PFO) channel and atrial septal pouches (SPs) are commonly described variants in humans. Recent discoveries on the clinical significance of left-sided SP may encourage the creation of new strategies and devices for the management of SPs. However, these strategies may first be tested in the ovine model before implementation in humans. Unfortunately, little is known about the presence of SPs in ovine. In this study a total of 60 ovine (Ovis aries) hearts were examined. The interatrial septum morphology was assessed and the PFO channel and SPs were measured. The most commonly occurring variant were PFO channels (25.0%) with channel lengths of 5.4±2.3 mm. Smooth septums were observed in 18.3% of hearts. In the remaining cases, septums had a left septal ridge (15.0%), left SP (11.7%), left septal bridge (10.0%), right SP (10.0%), or had both a right SP and left septal ridge (10.0%). No double SPs were observed. The mean right SP depth was 3.4 ± 1.2 mm, and its mean ostium width and height were 7.9±1.8 mm and 2.8±1.0, respectively. For the left SP, the mean depth was 6.0±1.7mm, the ostium width was 7.9±2.4mm, and the ostium height was 4.1±1.6mm (range: 2.3-6.4mm). In conclusion the interatrial septum of ovine hearts exhibit morphologies that are more similar to humans than they are to swine, which should be taken into account during experimental studies. The presence of a left SP in sheep hearts make ovine models a promising alternative to the human heart for developing left-sided SP management devices and techniques.

Temporal changes in the pattern of invasive angiography use and its outcome in suspected coronary artery disease: implications for patient management and healthcare resources utilization

INTRODUCTION

Invasive coronary angiography (CAG), the 'gold standard' in coronary artery disease (CAD) diagnosis, requires hospitalization, is not risk-free, and engages considerable healthcare resources.

AIM

To assess recent (throught out 10 years) evolution of 'significant' (≥ 50% stenosis(es)) CAD prevalence in subjects undergoing CAG for CAD diagnosis in a high-volume tertiary referral center.

MATERIAL AND METHODS

Anonymized medical records were compared for the last vs. the first 2-years of the decade (June 2007 to May 2018). Referrals for suspected CAD were 2067 of 4522 hospitalizations (45.7%) and 1755 of 5196 (33.8%) respectively (p < 0.001).

RESULTS

The median patient age (64 vs. 68 years) and the prevalence of heart failure (24.1% vs. 42.2%) increased significantly (p < 0.001). The CAG atherosclerotic lesions, for all stenosis categories (< 50%; ≥ 50%; ≥ 70%; occlusion(s)), were significantly more prevalent in men. The proportion of subjects with any atherosclerosis on CAG increased (80.7% vs. 77.6%, p = 0.015). However, in the absence of any gross change in, for instance, the fraction of women (40.4% vs. 41.8%), the proportion of CAGs with significant CAD (lesion(s) ≥ 50%) decreased from 55.2% in 2007/2008 to below 1 in every 2 angiograms (48.9%) in 2017/2018 (p < 0.001). This unexpected finding occurred consistently across nearly all CAG referral categories.

CONCLUSIONS

Despite more advanced age and a higher proportion of subjects with 'any' coronary atherosclerosis on CAG, the likelihood of a 'negative' angiogram (lesion(s) < 50%; no further evaluation/intervention) has increased significantly over the last decade. The exact nature of this phenomenon requires further investigation, particularly as a reverse trend would be expected with the growing role (and current high penetration) of contemporary non-invasive diagnostic tools to rule out significant CAD.

Coexistence and management of abdominal aortic aneurysm and coronary artery disease

BACKGROUND

Abdominal aortic aneurysm (AAA) and coronary atherosclerosis share common risk factors. In this study, a single-center management experience of patients with a coexistence of AAA and coronary artery disease (CAD) is presented.

METHODS

271 consecutive patients who underwent elective AAA repair were reviewed. Coronary imaging in 118 patients was considered suitable for exploration of AAA coexistence with CAD.

RESULTS

Significant coronary stenosis (> 70%) were found in 65.3% of patients. History of cardiac revascularization was present in 26.3% of patients, myocardial infarction (MI) in 31.4%, and 39.8% had both. In a subgroup analysis, prior history of percutaneous coronary intervention (PCI) (OR = 6.9, 95% CI 2.6-18.2, p < 0.001) and patients' age (OR = 1.1, 95% CI 1.0-1.2, p = 0.007) were independent predictors of significant coronary stenosis. Only 52.0% (40/77) of patients with significant coronary stenosis underwent immediate coronary revascularization prior to aneurysm repair: PCI in 32 cases (4 drug-eluting stents and 27 bare metal stents), coronary artery bypass graft in 8 cases. Patients undergoing revascularization prior to surgery had longer mean time from coronary imaging to AAA repair (123.6 vs. 58.1 days, p < 0.001). Patients undergoing coronary artery evaluation prior to AAA repair had shorter median hospitalization (7 [2-70] vs. 7 [3-181] days, p = 0.007) and intensive care unit stay (1 [0-9] vs. 1 [0-70] days, p = 0.014) and also had a lower rate of major adverse cardiovascular events or multiple organ failure (0% vs. 3.9%, p = 0.035). A total of 11.0% of patients had coronary artery aneurysms.

CONCLUSIONS

Patients with AAA might benefit from an early coronary artery evaluation strategy.