Volume 41 - Issue 2

INTRODUCTION: Chronic total occlusion (CTO) in the right coronary artery (RCA) is common in multivessel coronary artery disease. The impact of bypass grafting in the small target vessel (1.0-1.5 mm) of the RCA-CTO on outcomes is unknown.
METHODS: RCA-CTO was treated with either bypass grafting (RCA-bypass group) or non-bypass grafting (non-RCA-bypass group). The study compared the short- and long-term outcomes of patients who underwent coronary artery bypass grafting with or without the bypass grafting located in the small target vessel of the RCA-CTO.
RESULTS: A total of 426 patients were enrolled in the present study, including 376 patients in the RCA-bypass group and 50 patients in non-RCA-bypass group. The 30-day all-cause death in the RCA-bypass and non-RCA-bypass groups was 2.39% and 2.0% (P=0.999), respectively. The median follow-up time was 73 months. The long-term major adverse cardiac and cerebrovascular events in the RCA-bypass and non-RCA-bypass groups were 6.91% and 18% (P=0.013), respectively. There was a trend toward a higher rate of long-term freedom from major adverse cardiac and cardiovascular events within the RCA-bypass group (log-rank P=0.088).
CONCLUSIONS: The bypass grafting located in the small target vessel of the RCA-CTO did not affect the short-term outcomes, but it was associated with a reduced risk of long-term major adverse cardiac and cardiovascular events in patients who underwent coronary artery bypass grafting.

INTRODUCTION: Functionally univentricular hearts represent nearly 10% of all congenital heart defects, and the Fontan procedure is used in the heterogeneous group of patients who have them. Although early mortality after the Fontan procedure has declined internationally, data from middle-income countries remain scarce.
METHODS: This is a single-center retrospective observational study made through a review of the medical records of all pediatric patients who underwent the Fontan procedure from 2007 to 2020 in a public cardiac surgery referral center in Brazil.
RESULTS: Fontan procedure with an extracardiac conduit was performed in 78 children (52.6% female), predominantly for tricuspid atresia (55.1%), at a mean age of 12.1 ± 3.2 years. Preoperative oxygen saturation averaged 78.6 (± 7.4)%. Thirty-day mortality was 13.0%. Mortality decreased from 22.9% before 2015 to 4.8% after 2015 (P = 0.037), concurrent with yearly increase in surgical volume and a rise in operating-room extubation rates (from 2.9% to 47.6%, P = 0.001). One in five patients presented with malnutrition or low body weight. In the multivariate analysis, we found a hazard ratio of 65.05 (95% confidence interval: 7.923 – 534.1; P = 0.0001) for in-hospital mortality associated with postoperative acute kidney injury.
CONCLUSIONS: Patients underwent the Fontan procedure at a relatively late age. Mortality decreased over time alongside increased surgical volume and operating-room extubation rates. Nutritional status emerged as a potentially modifiable risk factor, whereas postoperative acute kidney injury was a strong independent predictor of in-hospital mortality, underscoring the critical impact of perioperative care.

INTRODUCTION: Median sternotomy can cause postoperative adhesions, raising bleeding and organ damage risks during resternotomies. Computed tomography angiography (CTA) and extended reality (XR) are increasingly used to enhance surgical planning and minimize these risks. This study aims to assess the benefits of integrating XR technology into resternotomy planning
METHODS: This multi-center study, conducted at the Sheba and Wolfson Medical Centers in Israel, evaluated the utility of three-dimensional imaging in surgical resternotomy planning in 24 cases. Pediatric and adult patients selected for resternotomy underwent routine CTA, and those with adequate image quality were used to generate virtual three-dimensional segmentation. The images were evaluated preoperatively.
RESULTS: The findings indicated no significant benefit of XR over CTA in terms of resternotomy anatomical data. However, the accuracy of the XR models varied with medical experience: senior physicians rated the XR as less accurate for adult patients than did residents, but the ratings were high in both groups for pediatric cases. The XR models improved the surgeons' understanding of chest anatomy in pediatrics more than in adult patients, whereas for surgical decision-making, XR was seen as more beneficial in pediatric cases, particularly by senior surgeons. Overall, senior physicians reported that XR influenced their surgical decisions more, suggesting that the utility of XR varies with physician experience and patient age.
CONCLUSION: XR technologies have shown considerable potential in enhancing visualization and contributing to determining surgical strategies. However, the extent of their influence in terms of reducing operative durations and minimizing intraoperative complications requires further investigation.

OBJECTIVE: This study aimed to investigate whether hsa_circ_0076767 exacerbates mitochondrial injury during myocardial ischemia/reperfusion injury (MI/RI) by targeting miR-140-3p and directly inhibiting the hypoxia-inducible factor (HIF)-1α/β-catenin pathway.
METHODS: MI/RI and hypoxia/reoxygenation (H/R) cell models were established. Reverse transcription-quantitative polymerase chain reaction (RT-qPCR) was performed to determine hsa_circ_0076767 expression in both the MI/RI models and to detect the subcellular localization of hsa_circ_0076767 and its responsiveness to ribonuclease R in HL-1 cells. A loss-of-function assay was performed to examine the function of hsa_circ_0076767 in cardiomyocyte mitochondrial and cardiac tissue injury following MI/RI. Hematoxylin-eosin staining and terminal deoxynucleotidyl transferase dUTP nick end labeling staining were used to assess myocardial tissue injury and apoptosis of myocardial tissues in mice, respectively. hsa_circ_0076767 was assayed for cell viability using Cell Counting Kit-8, for apoptosis using flow cytometry, for mitochondrial membrane potential using JC-1, and for cellular adenosine triphosphate content using commercial kits. RT-qPCR and protein blotting were performed to detect gene expression. Dual-luciferase, ribonucleic acid pull-down, and fluorescence in situ hybridization co-localization assays were used to validate the interaction between hsa_circ_0076767 and miR-140-3p. Finally, the regulatory relationship between hsa_circ_0076767 and the HIF-1α/β-catenin pathway was verified.
RESULTS: hsa_circ_0076767 was upregulated in myocardial tissues of MI/RI mice and H/R HL-1 cells. Silencing hsa_circ_007676767 ameliorated myocardial tissue injury, apoptosis, and mitochondrial damage in cardiomyocytes. hsa_circ_0076767 targets miR-140-3p. Moreover, hsa_circ_0076767 promoted mitochondrial injury by inhibiting the HIF-1α/β-catenin pathway.
CONCLUSION: hsa_circ_0076767 targets miR-140-3p and directly inhibits the HIF-1α/β-catenin pathway, exacerbating mitochondrial damage in cardiomyocytes during MI/RI.

INTRODUCTION: Despite the prevalence of cardiac fibrosis, there are currently no effective treatments to reverse it. A major obstacle is the lack of reliable in vitro models. An increase in angiotensin II and collagen occurs in cardiac fibrosis. Therefore, we hypothesized that the combination of angiotensin II with ascorbic acid and dextran sulfate could induce fibrosis in neonatal rat cardiac fibroblasts (nrCFs) and be used as an in vitro model of cardiac fibrosis.
METHODS: nrCFs were treated with angiotensin II, ascorbic acid, and dextran sulfate. Key features of cardiac fibrosis were evaluated using Alizarin Red, Picrosirius Red, Masson's trichrome staining, quantitative reverse transcription polymerase chain reaction, and immunocytochemistry and scratch assay.
RESULTS: Although dextran sulfate increased the expression of alpha-smooth muscle actin (α-SMA), it did not increase collagen deposition and cell migration. Therefore, it seems that the combination of 500 nM angiotensin II with 100 μM ascorbic acid would be effective in induction of cardiac fibrosis in vitro, which increased (1) the expression of collagen, α-SMA, and vimentin at protein level, (2) the expression of collagen type I alpha 1 chain, collagen type III alpha 1 chain, matrix metalloproteinase 2, and transforming growth factor-beta 1 at ribonucleic acid level, and (3) cell proliferation and migration.
CONCLUSION: In this study, 72 hour-treatment of nrCFs with 500 nM angiotensin II and 100 μM ascorbic acid was effective in the creation of an in vitro model of cardiac fibrosis. It is hoped that this model will be useful for screening antifibrotic treatments.

INTRODUCTION: Despite advancements in technique and the increasing number of coronary artery bypass grafting (CABG) procedures, new-onset postoperative atrial fibrillation (POAF) is one of the most common complications following CABG and remains a major concern. The exact mechanism is unclear, but impaired diastolic function may predispose patients to POAF. Thus, this study aims to evaluate preoperative diastolic dysfunction (DD) and associated factors as predictors of new-onset POAF.
METHODS: This retrospective cohort study involved patients undergoing CABG surgery who met the inclusion criteria between January 2018 to August 2022. DD was measured through preoperative transthoracic echocardiogram, while new-onset POAF was assessed through continuous electrocardiogram.
RESULTS: A total of 191 patients who met the inclusion criteria were enrolled in this study. Data-analysis revealed no significant difference in DD between patients with and without POAF (P = 0.72). Multivariate analysis demonstrated left main coronary artery disease (LMCAD) (odds ratio [OR] = 2.51; 95% confidence interval [CI] [1.12 – 5.59]; P = 0.02), in-stent restenosis (ISR) ≥ 70% (OR = 6.34; 95% CI [1.68 – 23.92]; P < 0.01), reduced ejection fraction ≤ 50% (OR = 2.18; 95% CI [0.94 – 5.06]; P = 0.07), and electrolyte imbalance (OR = 2.14; 95% CI [2.91 – 24.75]; P < 0.01) as the independent predictors of new-onset POAF.
CONCLUSION: DD was not identified as a predictor of new-onset POAF in patients undergoing CABG. The independent predictors identified in this study included male sex, comorbid LMCAD and ISR ≥ 70%, reduced left ventricular ejection fraction ≤ 50%, and postoperative electrolyte imbalance.

This review discusses the morphological characteristics of the human great saphenous vein (SV) harvested for coronary artery bypass grafting (CABG). It focuses on the vein's luminal intima, which was examined using laser confocal microscopy (LCM), transmission electron microscopy (TEM), and scanning electron microscopy (SEM). Summarised findings are: (1) LCM observations revealed that the vessel-like profiles, formed by the intima of the peripheral parts of SV luminal folds, may create a false impression that these are vasa vasorum vessels terminating at the vein lumen. (2) The SV luminal intima displays openings ranging from about 5 μm to 20 μm. Among these, larger openings (> 10 µm) are recognized as openings of small tributary branches rather than vasa vasorum vessels donating to SV lumen. It is suggested that these vessel openings are involved in the retrograde blood flow into the SV graft wall after CABG. In contrast, openings < 10 µm, or even those < 5 µm, did not show obvious vascular characteristics, suggesting these structures might have another physiological function. (3) In addition to the abovementioned openings, narrow, elongated intimal openings approximately 3 μm by 30 μm in size can be seen at the SEM level; these likely represent the entrances to the small folds detected by TEM in the inner media of the SV. Communication between the SV lumen and the vein vasa vasorum seems crucial for the anti-ischaemic protection of the vein as coronary graft. This issue, including the role of intimal openings, may require further investigation.

The saphenous vein is the most commonly used conduit in patients undergoing coronary artery bypass surgery. Graft patency is improved using the no-touch technique where the vein is harvested with minimal trauma, avoiding high pressure distension and maintaining normal vessel architecture. Various cells that are damaged when using conventional harvesting are preserved using the no-touch technique and are a source of nitric oxide. The no-touch technique is becoming accepted more widely as is the role of nitric oxide in improved saphenous vein graft patency. However, there are conflicting views regarding the tissue sources of nitric oxide.

Hybrid coronary revascularization combines minimally invasive surgical coronary artery bypass grafting with percutaneous coronary intervention. This case report describes a 72-year-old male with multivessel coronary artery disease treated using a hybrid approach: robot-assisted bilateral internal mammary artery grafting followed by percutaneous coronary intervention. This method leverages the strengths of both modalities, offering tailored treatment for specific coronary lesions. The patient's postoperative course was uneventful, and follow-up demonstrated excellent outcomes.

Cardiac hemangiomas are benign neoplasms of extremely rare occurrence and, in most cases, asymptomatic, commonly detected incidentally during examinations performed for other clinical indications. To confirm the diagnosis and prevent potential complications, surgical excision followed by histopathological analysis is recommended. In this case report, we describe a left ventricular hemangioma incidentally identified during an echocardiographic examination.