Infective Endocarditis: The role of PET imaging in diagnosis and management.

Positron emission tomography (PET) with 18F-fluorodeoxyglucose (18F-FDG) has recently emerged as an increasingly used alternative and supplementary imaging modality for the diagnosis of infective endocarditis. 18F-FDG PET/CT imaging for IE is given a Class I recommendation (level of evidence B) and is therefore recommended in cases of possible prosthetic valve IE to both detect valvular lesions, as well as confirm the diagnosis of IE. They have also given a class I recommendation (level of evidence B) for brain and whole-body 18F-FDG PET/CT and/or MRI imaging to detect peripheral lesions for patients with either native or prosthetic valve IE. Molecular imaging is playing an increasingly important role in the diagnosis and management of patients with IE. The important role of 18F-FDG PET/CT imaging has been acknowledged by recent guideline updates. These advanced imaging tests are not supplanting the role of echocardiography in the diagnostic pathway for IE. Rather, they are additional tools that are available where the diagnosis is complicated, difficult, or uncertain.

The Canadian Study of Arterial Inflammation in Patients with Diabetes and Recent Vascular Events, Evaluation of Colchicine Effectiveness (CADENCE): protocol for a randomised, double-blind, placebo-controlled trial.

BACKGROUND: Inflammation is a key mediator in the development and progression of the atherosclerotic disease process as well as its resultant complications, like myocardial infarction (MI), stroke and cardiovascular (CV) death, and is emerging as a novel treatment target. Trials involving anti-inflammatory medications have demonstrated outcome benefit in patients with known CV disease. In this regard, colchicine appears to hold great promise. However, there are potential drawbacks to colchicine use, as some studies have identified an increased risk of infection, and a non-significant trend for increased all-cause mortality. Thus, a more thorough understanding of the underlying mechanism of action of colchicine is needed to enable a better patient selection for this novel CV therapy. OBJECTIVE: The primary objective of the Canadian Study of Arterial Inflammation in Patients with Diabetes and Recent Vascular Events, Evaluation of Colchicine Effectiveness (CADENCE) trial is to assess the effect of colchicine on vascular inflammation in the carotid arteries and ascending aorta measured with 18F-fluorodeoxyglucose (FDG) positron emission tomography (PET)/CT in patients with type 2 diabetes mellitus (T2DM) or pre-diabetes who have experienced a recent vascular event (acute coronary syndrome (ACS)/MI, transient ischaemic attack (TIA) or stroke). Secondary objectives include determining colchicine's effect on inflammatory biomarkers (high-sensitivity C reactive protein (hs-CRP) and interleukin-6 (IL-6)). Additionally, we will assess if baseline inflammation imaging or biomarkers are associated with a treatment response to colchicine determined by imaging. Exploratory objectives will look at: (1) the difference in the inflammatory response to colchicine in patients with coronary events compared with patients with cerebral events; (2) the difference in the inflammatory response to colchicine in different vascular beds; (3) the relationship of FDG-PET imaging markers with serum biomarkers and (4) assessment of quality-of-life changes. METHODS AND DESIGN: CADENCE is a multicentre, prospective, randomised, double-blinded, placebo-controlled study to determine the effect of colchicine on arterial inflammation as assessed with imaging and circulatory biomarkers, specifically carotid arteries and aortic FDG uptake as well as hs-CRP and IL-6 among others. Patients with T2DM or pre-diabetes who have recently experienced a CV event (within 30-120 days after an ACS (ie, ST-elevation MI (STEMI) or non-STEMI)) or TIA/stroke with documented large vessel atherosclerotic disease will be randomised to treatment with either colchicine 0.6 mg oral daily or placebo. Participants will undergo baseline clinical evaluation including EQ5D assessment, blood work for inflammatory markers and FDG PET/CT scan of the ascending aorta and left and right carotid arteries. Patients will undergo treatment for 6 months and have repeat clinical evaluation including EQ5D assessment, blood work for inflammatory markers and FDG PET/CT scan at the conclusion of the study. The primary outcome will be the change in the maximum target to background ratio (TBRmax) in the ascending aorta (or carotid arteries) from baseline to follow-up on FDG PET/CT imaging. DISCUSSION: Colchicine is an exciting potential new therapy for CV risk reduction. However, its use is associated with side effects and greater understanding of its underlying mechanism of action is needed. Importantly, the current study will determine whether its anti-inflammatory action is an indirect systemic effect, or a more local plaque action that decreases inflammation. The results will also help identify patients who will benefit most from such therapy. TRIAL REGISTRATION NUMBER: NCT04181996.

Influence of preoperative frailty on quality of life after cardiac surgery: A systematic review and meta-analysis.

BACKGROUND: Frailty has emerged as an important prognostic marker of increased mortality after cardiac surgery, but its association with quality of life (QoL) and patient-centered outcomes is not fully understood. We sought to evaluate the association between frailty and such outcomes in older patients undergoing cardiac surgery. METHODS: This systematic review included studies evaluating the effect of preoperative frailty on QoL outcomes after cardiac surgery amongst patients 65 years and older. The primary outcome was patient's perceived change in QoL following cardiac surgery. Secondary outcomes included residing in a long-term care facility for 1 year, readmission in the year following the intervention, and discharge destination. Screening, inclusion, data extraction, and quality assessment were performed independently by two reviewers. Meta-analyses based on the random-effects model were conducted. The evidential quality of findings was assessed with the GRADE profiler. RESULTS: After the identification of 3105 studies, 10 observational studies were included (1580 patients) in the analysis. Two studies reported on the change in QoL following cardiac surgery, which was higher for patients with frailty than for patients without. Preoperative frailty was associated with both hospital readmission (pooled odds ratio [OR] 1.48 [0.80-2.74], low GRADE level) as well as non-home discharge (pooled OR 3.02 [1.57-5.82], moderate GRADE level). CONCLUSION: While evidence in this field is limited by heterogeneity of frailty assessment and non-randomized data, we demonstrated that baseline frailty may possibly be associated with improved QoL, but with increased readmission as well as discharge to a non-home destination following cardiac surgery. These patient-centered outcomes are important factors when considering interventional options for older patients. STUDY REGISTRATION: OSF registries (https://osf.io/vm2p8).

Radiolabeled Thioflavin-T Derivative PET Imaging for the Assessment of Cardiac Amyloidosis.

PURPOSE OF REVIEW: Cardiac amyloidosis (CA) is an often under-recognized cause of heart failure with preserved ejection fraction. The goal of the current paper was to review imaging modalities available for detecting cardiac amyloidosis. We wished to determine what modalities are available for the diagnosis of cardiac amyloidosis and what modalities could be utilized in the future. RECENT FINDINGS: Early and delayed planar imaging of the chest currently plays a central role in the workup and diagnosis of CA. However, novel positron emission tomography (PET) tracers could play a large role in CA imaging in the future. There is an increasing body of literature supporting the use of targeted amyloid-binding PET radiotracers such as 11C-Pittsburgh compound B (11C-PIB), 18F-florbetapir, -flutemetamol, and -florbetaben for the detection of cardiac amyloid. While planar imaging currently plays a large role in the workup of CA, PET imaging could play an increasing important role in the future. The quantitative abilities of novel PET tracers could theoretically allow for the serial monitoring of patients and detection of response to therapy, and the sensitive nature of the tracers could allow for even earlier disease detection. Further work with large randomized controlled trial data is needed in the development and validation of PET tracers for cardiac amyloid and represents an exciting development within the realm of nuclear cardiology.

Examining anti-inflammatory therapies in the prevention of cardiovascular events: protocol for a systematic review and network meta-analysis of randomised controlled trials.

INTRODUCTION: Inflammation is emerging as an important risk factor for atherosclerotic cardiovascular disease and has been a recent target for many novel therapeutic agents. However, comparative evidence regarding efficacy of these anti-inflammatory treatment options is currently lacking. METHODS AND ANALYSIS: This systematic review will include randomised controlled trials evaluating the effect of anti-inflammatory agents on cardiovascular outcomes in patients with known cardiovascular disease. Studies will be retrieved from Medline, Embase, the Cochrane Central Register of Controlled Trials, as well as clinical trial registry websites, Europe PMC and conference abstract handsearching. No publication date or language restrictions will be imposed. Eligible interventions must have some component of anti-inflammatory agent. These include (but are not limited to): non-steroidal anti-inflammatory drugs (NSAIDs), colchicine, prednisone, methotrexate, canakinumab, pexelizumab, anakinra, succinobucol, losmapimod, inclacumab, atreleuton, LP-PLA2 (darapladib) and sPLA2 (varespladib). The primary outcomes will include major adverse cardiac events (MACE), and each individual component of MACE (myocardial infarction, stroke and cardiovascular death). Key secondary outcomes will include unstable angina, heart failure, all-cause mortality, cardiac arrest and revascularisation. Screening, inclusion, data extraction and quality assessment will be performed independently by two reviewers. Network meta-analysis based on the random effects model will be conducted to compare treatment effects both directly and indirectly. The quality of the evidence will be assessed with appropriate tools including the Grading of Recommendations, Assessment, Development and Evaluation profiler or Confidence in Network Meta-Analysis tool. ETHICS AND DISSEMINATION: Ethics approval is not required for this systematic review. The findings will be disseminated through a peer-reviewed journal. PROSPERO REGISTRATION NUMBER: CRD42022303289.

Influence of preoperative frailty on quality of life after cardiac surgery: Protocol for a systematic review and meta-analysis.

BACKGROUND: Frailty has emerged as an important prognostic marker of adverse outcomes after cardiac surgery, but evidence regarding its ability to predict quality of life after cardiac surgery is currently lacking. Whether frail patients derive the same quality of life benefit after cardiac surgery as patients without frailty remains unclear. METHODS: This systematic review will include interventional studies (RCT and others) and observational studies evaluating the effect of preoperative frailty on quality-of-life outcomes after cardiac surgery amongst patients 65 years and older. Studies will be retrieved from major databases including the Cochrane Central Register of Controlled Trials, Embase, and Medline. The primary exposure will be frailty status, independent of the tool used. The primary outcome will be change in quality of life, independent of the tool used. Secondary outcomes will include readmission during the year following the index intervention, discharge to a long-term care facility and living in a long-term care facility at one year. Screening, inclusion, data extraction and quality assessment will be performed independently by two reviewers. Meta-analysis based on the random-effects model will be conducted to compare the outcomes between frail and non-frail patients. The evidential quality of the findings will be assessed with the GRADE profiler. CONCLUSION: The findings of this systematic review will be important to clinicians, patients and health policy-makers regarding the use of preoperative frailty as a screening and assessment tool before cardiac surgery. STUDY REGISTRATION: OSF registries (https://osf.io/vm2p8).

Right heart function deteriorates in breast cancer patients undergoing anthracycline-based chemotherapy.

BACKGROUND: Cardiotoxicity from anthracycline-based chemotherapy is an important cause of early and late morbidity and mortality in breast cancer patients. Left ventricular (LV) function is assessed for patients receiving anthracycline-based chemotherapy to identify cardiotoxicity. However, animal studies suggest that right ventricular (RV) function may be a more sensitive measure to detect LV dysfunction. The purpose of this pilot study was to determine if breast cancer patients undergoing anthracycline-based chemotherapy experience RV dysfunction. METHODS: Forty-nine breast cancer patients undergoing anthracycline-based chemotherapy at the Ottawa Hospital between November 2007 and March 2013 and who had 2 echocardiograms performed at least 3months apart were retrospectively identified. Right atrial area (RAA), right ventricular fractional area change (RV FAC) and RV longitudinal strain of the free wall (RV LSFW) were evaluated according to the American Society of Echocardiography guidelines. RESULTS: The majority (48/49) of patients were females with an average age of 53.4 (95% CI: 50.1-56.7years). From baseline to follow-up study, average LV ejection fraction (LVEF) decreased from 62.22 (95% CI: 59.1-65.4) to 57.4% (95% CI: 54.0-60.9) (P=0.04). During the same time period, the mean RAA increased from 12.1cm(2) (95% CI: 11.1-13.0cm(2)) to 13.8cm(2) (95% CI: 12.7-14.9cm(2)) (P=0.02), mean RV FAC decreased (P=0.01) from 48.3% (95% CI: 44.8-51.74) to 42.1% (95% CI: 38.5-45.6%), and mean RV LSFW worsened from -16.2% (95% CI: -18.1 to -14.4%) to -13.81% (95% CI: -15.1 to -12.5%) (P=0.04). CONCLUSION: This study demonstrates that breast cancer patients receiving anthracycline-based chemotherapy experience adverse effects on both right atrial size and RV function. Further studies are required to determine the impact of these adverse effects on right heart function and whether this represents an earlier marker of cardiotoxicity.