Do Flow and Pulsatility Index within the Accepted Ranges Predict Long-Term Outcomes after Coronary Artery Bypass Grafting?

BACKGROUND: Transit-time flow measurement (TTFM) is the gold standard for intraoperative detection of graft failure. Several reports show that TTFM and distal coronary bed quality (DCBQ) may also be useful for midterm detection of graft failure. Nonetheless, there are no data regarding their predictive role on long-term outcomes. METHODS: Patients with three-vessel disease who underwent isolated coronary artery bypass grafting (CABG) in 2006 and received at least one graft to the left anterior descending artery (LAD) or to the first obtuse marginal (OM1) or posterior descending artery (PDA) were included. Baseline characteristics, mean graft flow, pulsatility index, and subjective impression of DCBQ for each coronary territory were collected. Long-term cardiovascular (CV) and overall survival, operative mortality, and new percutaneous coronary intervention (PCI) were evaluated. RESULTS: A total of 177 patients underwent isolated CABG. The OM1 was grafted in 131 patients, the LAD in 169 patients, and the PDA in 100 patients. Neither DQCB nor TTFM were predictors for new PCI. Independent predictors for overall survival were age, previous acute myocardial infarction (AMI), and DQCB of OM1 (odds ratio [OR] = 2.97; 95% confidence interval [CI]: 1.15-7.71). Age, previous AMI, and DCBQ of OM1 (OR = 2.5; 95% CI: 1.39-4.81) were independent predictors for CV survival. CONCLUSIONS: TTFM on patients with functioning grafts does not predict long-term survival or performance of new PCI. Subjective evaluation of distal coronary bed, especially of the OM1, has a strong impact on long-term outcomes.

Human mesenchymal stromal cells do not promote recurrence of soft tissue sarcomas in mouse xenografts after radiation and surgery.

BACKGROUND: Mesenchymal stromal cells (MSCs) promote wound healing, including after radiotherapy (RT) and surgery. The use of MSCs in regenerative medicine in the context of malignancy, such as to enhance wound healing post-RT/surgery in patients with soft tissue sarcomas (STSs), requires safety validation. The aim of this study was to determine the effects of human MSCs on STS growth in vitro and local recurrence and metastasis in vivo. METHODS: Human primary STS and HT-1080 fibrosarcoma lines were transduced to express luciferase/eGFP (enhanced green fluorescent protein). Sarcoma cells were co-cultured or co-injected with bone marrow-derived MSCs for growth studies. Xenograft tumor models were established with STS lines in NOD/SCID/γcnull mice. To emulate a clinical scenario, subcutaneous tumors were treated with RT/surgery prior to MSC injection into the tumor bed. Local and distant tumor recurrence was studied using histology and bioluminescence imaging. RESULTS: MSCs did not promote STS proliferation upon co-culture in vitro, which was consistent among MSCs from different donors. Co-injection of MSCs with sarcoma cells in mice exhibited no significant tumor-stimulating effect, compared with control mice injected with sarcoma cells alone. MSC administration after RT/surgery had no effect on local recurrence or metastasis of STS. DISCUSSION: These studies are important for the establishment of a safety profile for MSC administration in patients with STS. Our data suggest that MSCs are safe in STS management after standard of care RT/surgery, which can be further investigated in early-phase clinical trials to also determine the efficacy of MSCs in reducing morbidity and to mitigate wound complications in these patients.

Development and characterization of a new inbred transgenic rat strain expressing DsRed monomeric fluorescent protein.

The inbred rat is a suitable model for studying human disease and because of its larger size is more amenable to complex surgical manipulation than the mouse. While the rodent fulfills many of the criteria for transplantation research, an important requirement is the ability to mark and track donors cells and assess organ viability. However, tracking ability is limited by the availability of transgenic (Tg) rats that express suitable luminescent or fluorescent proteins. Red fluorescent protein cloned from Discosoma coral (DsRed) has several advantages over other fluorescent proteins, including in vivo detection in the whole animal and ex vivo visualization in organs as there is no interference with autofluorescence. We generated and characterized a novel inbred Tg Lewis rat strain expressing DsRed monomeric (DsRed mono) fluorescent protein under the control of a ubiquitously expressed ROSA26 promoter. DsRed mono Tg rats ubiquitously expressed the marker gene as detected by RT-PCR but the protein was expressed at varying levels in different organs. Conventional skin grafting experiments showed acceptance of DsRed monomeric Tg rat skin on wild-type rats for more than 30 days. Cardiac transplantation of DsRed monomeric Tg rat hearts into wild-type recipients further showed graft acceptance and long-term organ viability (>6 months). The DsRed monomeric Tg rat provides marked cells and/or organs that can be followed for long periods without immune rejection and therefore is a suitable model to investigate cell tracking and organ transplantation.

Composite end points and competing risks analysis.

Composite end points are common primary outcomes in clinical trials. Their main benefit of utilizing a composite outcome is increasing the number of primary outcome events, meaning fewer participants are required to deliver an adequately powered trial. By combining multiple important end points in the primary outcome rather than having to select only 1, composite end points potentially make clinically meaningful benefits easier to detect and avoid ranking outcomes hierarchically. However, there are a number of important considerations when designing and interpreting clinical trials that utilize composite end points. In this Statistical Primer, issues with composite end points such as competing events, halo effect, risk of bias, time-to-event limitations and the win ratio are discussed in the context of real world clinical trials.

Early anticoagulation after aortic valve replacement with porcine bioprosthesis randomized control trial(ANTIPRO). 3 years follow-up.

BACKGROUND: Most evidence for anticoagulation in aortic bioprosthesis is centered on embolic events, bleeding and re-intervention risk. The effect of anticoagulation on hemodynamics has not been previously assessed. Our hypothesis was that patients with anticoagulation (AC) early after aortic valve replacement (AVR) with porcine bioprosthesis have better hemodynamics at 3 years of follow-up. METHODS: This is a follow-up evaluation of the ANTIPRO trial. All patients undergoing AVR with porcine bioprosthesis were consecutively recruited. The AC group received warfarin+aspirin and the non-AC(control) only aspirin. The primary outcome was mean gradient after 3 years of AVR and change in New York Heart Association (NYHA) class. Secondary outcomes were major and minor bleeding and embolic events. RESULTS: Of 140 participants in the study, 71 were assigned to the AC group and 69 to the control group. Mean age of the overall population was 72.4(SD: 7.1) years. Global euroSCORE was 7.65(SD: 5.73). At 3 years the mean gradient was similar between both groups (19.4(SD: 9.6 mmHg) and 18.6(SD: 8.2 mmHg) in the control and AC group respectively, p = 0.7). No differences in functional class at 3 years were found among groups. No differences were found among groups in the secondary outcomes. CONCLUSIONS: The addition of 3 months of oral anticoagulation to anti-aggregation treatment did not affect bioprosthetic hemodynamics nor functional class at years after AVR.

Warfarin use is associated with higher aortic bioprosthetic 18F-fluoride PET uptake.

BACKGROUND: Prevalence of bioprosthetic valve degeneration (BVD) is rising as the use of bioprosthetic aortic valves increases. Detecting early signs of BVD remains a challenge, with conventional imaging methods often failing to identify early deterioration stages. 18F-fuoride positron emission tomography (PET-CT) is an emerging technique that offers promising prospects to detect subclinical BVD. This study aimed to compare early PET parameters of fluoride uptake with echocardiographic hemodynamic parameters and compare outcomes according to anticoagulation in patients who received bioprosthetic valves. METHODS: This is a sub-study of the ANTIPRO clinical trial, which involved patients undergoing surgical aortic valve replacement (SAVR) with a porcine bioprosthesis and randomized them into anticoagulated and non-anticoagulated groups. Hemodynamic changes were assessed by transthoracic echocardiography (TTE), while 18F-fluoride PET-CT quantified fluoride uptake and divided the patients in two groups: high-uptake and low-uptake. Mean and maximum gradients by TTE at three years were compared between the two uptake groups. Fluoride uptake was also compared between the anticoagulated and control groups. RESULTS: We found no significant differences in transprosthetic gradients between high-uptake(21.4 ± 8.6 mmHg) and low-uptake(17.3 ± 11.2 mmHg.p = 0.244) PET-defined groups in this specific timeframe. Notably, anticoagulated patients exhibited significantly risk of higher fluoride uptake(OR = 4.34;95%CI:1.04-18.21.p = 0.045). CONCLUSIONS: No association was found between fluoride uptake and hemodynamic evaluation. Anticoagulation was associated with higher fluoride uptake. These findings highlight the emerging role of PET-CT in studying bioprosthetic aortic valves and emphasize the need for extended follow-up to evaluate the impact of anticoagulation on valve degeneration.

"A stratified pathway to stent-free reperfusion: Selecting suitable patients in ST-elevation myocardial infarction".

BACKGROUND: The DANAMI-3 DEFER study demonstrated that deferring stent implantation in ST-elevation myocardial infarction (STEMI) is safe, although not superior to immediate stenting. It is possible that an individualized revascularization strategy in STEMI, achieved through appropriate patient selection, could be feasible and effective. METHODS: This prospective, non-randomized study included 198 patients with STEMI who underwent primary percutaneous coronary intervention (PCI) between October 2019 and November 2021. Patients were assigned to either the deferred stenting (DS) group (n = 19) or the control group (C) undergoing immediate stenting (n = 179) based on a multimodal approach integrating coronary angiography, intravascular imaging, physiological assessments, and clinical judgment. The primary endpoints included all-cause mortality and major adverse cardiac and cerebrovascular events (MACCE). RESULTS: The DS group showed a significantly lower rate of stent implantation (10.5 % vs. 97.7 %, p < 0.001) and a higher use of thrombus aspiration (89.5 % vs. 30.7 %, p < 0.001) and glycoprotein IIb/IIIa inhibitors (31.6 % vs. 6.7 %, p < 0.001) compared to the C group. No significant differences were observed between the groups in terms of all-cause mortality (5.3 % vs. 8.9 %, p = 0.59) or MACCE (10.5 % vs. 8.4 %, p = 0.71). CONCLUSIONS: This study demonstrates the feasibility of implementing individualized reperfusion strategies in STEMI within a real-world clinical setting. The findings, while limited by the study design, generate valuable hypotheses that warrant further investigation to refine patient selection criteria and optimize outcomes.

Conflicts of interest in clinical practice: lessons learned from cardiovascular medicine.

Cardiovascular diseases represent a major burden worldwide, and clinical trials are critical to define treatment improvements. Since various conflicts of interest (COIs) may influence trials at multiple levels, cardiovascular research represents a paradigmatic example to analyze their effects and manage them effectively to re-establish the centrality of evidence-based medicine.Despite the manifest role of industry, COIs may differently affect both sponsored and non-sponsored studies in many ways. COIs influence may start from the research question, data collection and adjudication, up to result reporting, including the spin phenomenon. Outcomes and endpoints (especially composite) choice and definitions also represent potential sources for COIs interference. Since large randomized controlled trials significantly influence international guidelines, thus impacting also clinical practice, their critical assessment for COIs is mandatory. Despite specific protocols aimed to mitigate COI influence, even scientific societies and guideline panels may not be totally free from COIs, negatively affecting their accountability and trustworthiness.Shared rules, awareness of COI mechanisms and transparency with external data access may help promoting evidence-based research and mitigate COIs impact. Managing COIs effectively should preserve public trust in the cardiovascular profession without compromising the positive relationships between investigators and industry.

The ISCHEMIA trial revisited: setting the record straight on the benefits of coronary bypass surgery and the misinterpretation of a landmark trial.

OBJECTIVES: The ISCHEMIA trial is a landmark study that has been the subject of heated debate within the cardiovascular community. In this analysis of the ISCHEMIA trial, we aim to set the record straight on the benefits of coronary artery bypass grafting (CABG) and the misinterpretation of this landmark trial. We sought to clarify and reorient this misinterpretation. METHODS: We herein analyse the ISCHEMIA trial in detail and describe how its misinterpretation has led to an erroneous guideline recommendation downgrading for prognosis-altering surgical therapy in these at-risk patients. RESULTS: The interim ISCHEMIA trial findings align with previous evidence where CABG reduces the long-term risks of myocardial infarction and mortality in advanced coronary artery disease. The trial outcomes of a significantly lower rate of cardiovascular mortality and a higher rate of non-cardiovascular mortality with the invasive strategy are explained according to landmark evidence. CONCLUSIONS: The ISCHEMIA trial findings are aligned with previous evidence and should not be used to downgrade recommendations in recent guidelines for the indisputable benefits of CABG.

Coronary surgery provides better survival than drug-eluting stent: A pooled meta-analysis of Kaplan- Meier-derived individual patient data.

OBJECTIVES: We explored the current evidence on coronary disease treatment comparing the survival of 2 therapeutic strategies: coronary artery bypass grafting (CABG) and percutaneous coronary intervention (PCI) with drug-eluting stent (DES). METHODS: PubMed, Embase, and Google Scholar were searched for randomized clinical trials comparing CABG versus PCI with DES. The end point was overall mortality. Two statistical approaches were used: the generic inverse variance method, which was used to pool the incident rate ratios, and the pooled meta-analysis of Kaplan-Meier-derived individual patient data. RESULTS: Eight randomized clinical trials comparing 4975 patients undergoing CABG and 4992 patients undergoing PCI were included in our meta-analysis. Generic inverse variance method showed a statistically significant survival benefit of the CABG group (incident rate ratio, 1.21; 95% confidence interval, 1.09-1.35; P < .01). The Kaplan-Meier estimates of survival at 1, 5, and 10 years of the CABG group were 97.1%, 90.3%, and 80.3%, respectively. The Kaplan-Meier estimates of survival at 1, 5, and 10 years of the PCI group were 97.0%, 87.7%, and 76.4%, respectively. The log-rank analysis confirmed a statistically significant benefit in term of overall mortality of the CABG group (hazard ratio, 1.24; 95% confidence interval, 1.11-1.38; P = .0001). CONCLUSIONS: The present meta-analysis suggests that CABG provides a consistent survival benefit over PCI with DES.

Perspectives in Training and Professional Practice of Cardiac Surgery in Latin America.

INTRODUCTION: There is a lack of information about cardiac surgery training and professional practice in Latin American (LATAM) countries. This study is the first comparative analysis of cardiac surgical training and professional practice across LATAM and provides the fundamentals for future academic projects of the Latin American Association of Cardiac and Endovascular Surgery (LACES). METHODS: International survey-based comparative analysis of the training and professional practice of cardiac surgeons across LATAM. Trainees (residents/fellows) and staf (graduated) surgeons from LATAM countries were included. RESULTS: A total of 289 respondents (staf surgeons N=221 [76.5%]; residents/fellows N=68 [23.5%]) from 18 different countries participated in the survey. Most surgeons (N=92 [45.3%]) reported being unsatisfied with their salaries. Most respondents (N=181 [62.6%]) stated that it was difficult to obtain a leadership position, and 149 (73.8%) stated that it was difficult to find a job after completing training. Only half of the trainee respondents (N=32 [47.1%]) reported that their program had all resident spots occupied. Only 22.1% (N=15) of residents/fellows were satisfied with their training programs. The majority (N=205 [70.9%]) of respondents would choose cardiac surgery as their specialty again. Most surgeons (N=129 [63.9%]) and residents/fellows (N=52 [76.5%]) indicated that the establishment of a LATAM cardiac surgery board examination would be beneficial. CONCLUSION: Modernization and standardization of training, as well as greater access to opportunities, may be required in LATAM to increase professional satisfaction of cardiac surgeons and to reduce disparities in the specialty. Such changes may enhance the regional response to the dynamic challenges in the feld.

Early anticoagulation after aortic valve replacement with porcine bioprosthesis randomized control trial (ANTIPRO).

OBJECTIVES: Most evidence for anticoagulation (AC) in aortic bioprosthesis is centred on embolic events, bleeding and reintervention risk. The effect of AC on haemodynamics has not been previously assessed. Our hypothesis was that patients with early AC after aortic valve replacement (AVR) with porcine bioprosthesis have better haemodynamics at 1 year of follow-up. METHODS: Prospective, randomized, open-label trial conducted at 2 cardiac surgery centres. All patients undergoing AVR with porcine bioprosthesis were consecutively recruited. The anticoagulated group received warfarin + aspirin and the non-anticoagulated (control) only aspirin. The primary outcome was mean gradient after 1 year of AVR and change in New York Heart Association class. Secondary outcomes were major and minor bleeding, embolic events and prosthetic leak. RESULTS: Of 140 participants in the study, 71 were assigned to the anticoagulated group and 69 to the control group. The mean age of the overall population was 72.4 (SD: 7.1) years. Global EuroSCORE was 7.65 (SD: 5.73). At 1 year, the mean gradient was similar between both groups [18.6 (SD: 1.1 mmHg) and 18.1 (SD: 1.0 mmHg) in the control and anticoagulated groups, respectively, P = 0.701]. No differences in functional class at 3 months or 1 year were found among groups. No differences were found among groups in the secondary outcomes. CONCLUSIONS: The addition of 3 months of oral AC to anti-aggregation treatment was not detected to affect bioprosthetic haemodynamics nor functional class at 1 year after AVR. Likewise, AC does not lead to the higher incidence of complications.

Non-Governmental Organizations Delivering Global Cardiac Surgical Care: A Quantitative Impact Assessment.

In low- and middle-income countries (LMICs), 93% of the population lacks safe, timely, and affordable access to cardiac surgical care when needed. As countries slowly build or expand local, independent cardiac centers, non-governmental organizations (NGOs) partially bridge the gap in cardiac surgical care delivery in LMICs. However, little is known about the current scope of cardiac NGOs. Here, we perform an analysis of active NGOs involved with the delivery of cardiac surgical services in LMICs or for patients from LMICs. Cardiac surgery NGOs were identified from medical literature, established NGO databases, and Google Scholar searches. The search was performed between December 2019 and May 2020. NGOs whose websites were not updated or described missions or projects taking place no later than 2015 were considered inactive. Eighty-six NGOs are actively providing cardiac surgery services in LMICs or treating patients from LMICs. Five NGOs performed adult cardiac surgery only, 56 performed pediatric cardiac surgery only, and 25 performed both adult and pediatric cardiac surgery. NGOs originated from 23 different countries and were operational in a total of 111 countries, 96 of them being LMICs. Fifty-three NGOs reported data on annual surgical volume, of which half performed less than 50 operations per year. NGOs effectively address the burden of cardiac surgical disease in LMICs and contribute to local capacity-building. Increased, more detailed, and standardized reporting of the impact and outcomes of NGOs is necessary to better understand annual cardiac surgical volume and to support local centers working towards independent services.

Joint Recommendations From The Latin American Association of Cardiac and Endovascular Surgery (LACES) and The Cardiovascular Anesthesia Committee of The Latin American Confederation of Anesthesia Societies (CLASA) on the Timing for Cardiac Surgery After COVID-19 Infection.

INTRODUCTION: Since the coronavirus disease 2019 (COVID-19) pandemic, cardiac surgeries in patients with previous infection by COVID-19 were suspended or postponed, which led to surgeries performed in patients with an advanced stage of their disease and an increase in the waiting list. There is a heterogeneous attitude in Latin America on the optimal timing to cardiac surgery in patients with previous COVID-19 infection due to scarce data on its outcome. Two Latin American associations joined to establish common suggestions on the optimal timing of surgery in patients with previous COVID-19 infection. METHODS: Data collection was performed using a pre-established form, which included year of publication, objective, type of study (prospective/retrospective, descriptive/analytical), number of patients, year of study, waiting time between infection and surgery, type of surgery, morbidity, mortality, and conclusions regarding the association between mortality and morbidity. Final recommendations were approved by the board of directors of Latin American Association of Cardiac and Endovascular Surgery (LACES) and Latin American Confederation of Anesthesia Societies (CLASA). RESULTS: Of the initial 1,016 articles, 11 comprised the final selection. Only six of them included patients who underwent cardiac surgery. According to the analyzed literature, optimal timing for cardiac surgery needs to consider the following aspects: deferable surgery, symptomatic COVID-19 infection, completeness of COVID-19 vaccination. CONCLUSION: These recommendations derive from the analysis of the scarce literature published at present on outcomes after cardiac surgery in patients with previous COVID-19 infection. These are to be taken as a dynamic recommendation in which Latin American reality was taken into consideration.

Mesenchymal stromal cells mediate a switch to alternatively activated monocytes/macrophages after acute myocardial infarction.

Given the established anti-inflammatory properties of mesenchymal stromal cells (MSCs), we investigated their effect on inflammatory cell infiltration of ischemic cardiac tissue and cardiac function. We employed two types of MSCs, human bone marrow-derived (BM) MSCs and human umbilical cord perivascular cells in an experimental acute myocardial infarction (MI) model with the immune-deficient NOD/SCID gamma null mouse. Cells were infused 48 h after induction of MI and mice assessed 24 h later (72 h after MI) for bone marrow (BM), circulating and cardiac tissue-infiltrating monocytes/macrophages. We showed that in the presence of either MSC type, overall macrophage/monocyte levels were reduced, including pro-inflammatory M1-type macrophages, while the proportion of alternatively activated M2-type macrophages was significantly increased in the circulation and heart but not the BM. Moreover, we found decreased expression of IL-1ß and IL-6, increased IL-10 expression and fewer apoptotic cardiomyocytes without changes in angiogenesis in the infarct area. Fractional shortening was enhanced 2 weeks after cell infusion but was similar to medium controls 16 weeks after MI. In vitro studies showed that BM MSCs increased the frequency of alternatively activated monocytes/macrophages, in part by MSC-mediated secretion of IL-10. Our data suggest a new mechanism for MSC-mediated enhancement of cardiac function, possibly via an IL-10 mediated switch from infiltration of pro-inflammatory to anti-inflammatory macrophages at the infarct site. Additional studies are warranted confirming the role of IL-10 and augmenting the anti-inflammatory effects of MSCs in cardiac regeneration.