Cardiac magnetic resonance relaxometry compared to left ventricular ejection fraction in the identification of anthracycline related cardiac changes: a systematic review and meta-analysis

Background

Anthracyclines are associated with cancer therapeutics related cardiac dysfunction (CTRCD). The identification of CTRCD currently uses a change in left ventricular ejection fraction (LVEF). Myocardial damage associated with anthracyclines include myocardial inflammation and oedema. This can be assessed using cardiac magnetic resonance (CMR) relaxometry techniques; T1 and T2 mapping and extracellular volume (ECV) fraction.

Purpose

In this meta-analysis, we compared the magnitude of the changes in LVEF and CMR relaxometry techniques wihtin a month of anthracycline therapy completion.

Methods

We performed a structured literature review as per the PRISMA guidelines across three databases (EMBASE, MEDLINE, and SCOPUS) for studies evaluating CMR relaxometry parameter at baseline and soon after completion of anthracycline therapy (3–5 months post baseline). CMR parameters pre and post anthracycline-based chemotherapy were abstracted. A random effects model was used to pool mean difference (MD) in LVEF and ECV given standardisation in imaging acquisition techniques. A random effects model was used to pool standardized mean difference (SMD) in LVEF, T1, T2 and ECV after anthracycline to adjust for variations in imaging techniques and comparison between techniques.

Results

A total of 174 patients were included from seven studies. 91% were female with a mean age of 55.6 years. The pooled MD in LVEF and ECV was −3.15% [95% CI −4.99, −1.31] and 1.61% [0.90, 2.32], respectively. The pooled SMD in LVEF, T1, T2 and ECV was −0.61 [−0.96, −0.25] 0.34 [0.04, 0.63], 0.67 [0.12,1.21], 0.6 [0.31, 0.89], respectively (Table 1).

Conclusions

T2 mapping, ECV and LVEF can identify early myocardial changes better than T1 mapping. These changes suggest there is marked oedema in the myocardial injury from anthracycline therapy. Whilst these findings support the role of CMR relaxometry in identifying CTRCD, further studies are required.

Funding Acknowledgement

Type of funding sources: None.

Cardioprotection against cardiac dysfunction from breast cancer chemotherapy: a bayesian and frequentist network meta-analysis of randomised controlled trials

Background

Anthracyclines (ANT) are the cornerstone of multiple chemotherapy regimens but at the risk of potential cardiotoxicity. Previous RCTs have tested the prophylactic effects of multiple cardioprotective agents to prevent ANT-related cardiotoxicity. Unfortunately, attempts to combine RCT findings in previous meta-analyses have been heterogeneous, creating further uncertainty. There remains an unmet need to determine the role of cardio-protective agents in breast cancer.

Purpose

To assess the comparative efficacy of cardioprotective drugs in patients with breast cancer using both Bayesian and frequentist analyses of randomised controlled trials

Methods

We performed a systematic review using four databases (CENTRAL, Cochrane Reviews, MEDLINE, SCOPUS), to find RCTs evaluating cardio protective drugs in breast cancer patients without prior ANT exposure. The population included was anthracycline naïve, and trials were excluded if cardio-protective agents were commenced post anthracycline treatment. The primary outcome was a mean change in LVEF pre and post ANT dosing. Results were pooled with both Bayesian and frequentist approaches using random effects models in R statistical software.

Results

We identified 12 RCTs from 2807 search results (n=1126, Age 51 years, ANT dose 412m/m2, baseline LVEF 62.6%) with comparisons including beta-blockers (BB) (n=9), Angiotensin Converting Enzyme inhibitors (ACEi)/Angiotensin Receptor Blockers (ARB) (n=3), combination BB + AA (n=2), spironolactone (n=1) and statins (n=1). All included trials had either intermediate or high risk of bias, with marked heterogeneity in ANT dosing and LVEF monitoring. Overall, our Bayesian network meta-analysis showed no statistically significant difference in mean LVEF preservation between AA (1.3%, 95% credible interval [−0.20, 2.9]), BB (0.77, [−0.21, 1.8]), AABB (0.84 [−1.1, 2.8]), SPR (0.72, [−2.3, 3.7]) or statin (0.60, [−2.4, 3.6]) when compared against placebo. After ranking for efficacy, ACEi/ARBs achieved the most protection against LVEF decline of 1.3% [95% CI: −0.2, 2.9] although still not significant. Conversely, frequentist analysis showed benefit in using AA (Standardised Mean Difference (SMD) 1.32% [0.32, 2.33]) and BB (SMD 0.76% [0.12, 1.4]).

Conclusion

Bayesian analysis demonstrated no difference in LVEF with cardio-protective agents. In contrast, frequentist analysis showed that AA and BB may provide significant cardio-protection. The quality of RCT data to date is limited by a high risk of bias and significant heterogeneity between RCA reporting. Larger trials with clear population definition are required to determine whether any drug class provides benefit in this setting.

Funding Acknowledgement

Type of funding sources: None.

Coronary perforation incidence and temporal trends (COPIT): systematic review and meta-analysis

Background

Despite advancements in Percutaneous Coronary Intervention (PCI) technology and techniques, iatrogenic coronary artery perforation (CAP) remains a dreaded potential complication within the cardiac catheterisation laboratory. Data detailing the incidence of coronary perforation during PCI has previously been obtained from relatively small datasets. A swell of large data published in recent times provides invaluable information regarding PCI related CAP.

Purpose

COPIT is a systematic review and meta-analysis targeted at detailing the incidence, outcomes, etiology and treatment modalities of PCI related CAP including evaluation of temporal trends since the inception of PCI to contemporary practice. Additionally, COPIT provides hypothesis generating data regarding predictors of CAP during PCI.

Methods

A prospective systematic review and meta-analysis using MEDLINE and EMBASE via the OVID interface (PROSPERO ID: CRD42020207881) was performed according to the PRISMA guidelines. Identified relevant studies were used in a pre-specified sensitivity analysis to detail incidence, outcomes, etiology, treatment modalities and risk factors of PCI complicated by CAP. Studies limited to PCI in high risk populations only such as CTO-PCI or rotational atherectomy only were excluded.

Results

67 studies met eligibility criteria detailing 5,568,191 PCIs over a 38-year period (1982–2020). The pooled incidence of CAP was 0.39% (95% CI: 0.34–0.45%) with no change in incidence over that time. Approximately 1 in 5 perforations led to cardiac tamponade (21.1%). Ellis 3 perforations are increasing in frequency and account for 43% of all perforations. Mortality due to perforation occurs in 7.5% of all CAP (95% CI 6.7% - 8.4%) but has declined over the studied period. Meta-regression suggested that female gender, hypertension, chronic kidney disease and previous coronary bypass grafting were all associated with higher incidence of CAP. Coronary perforation was most frequently caused by distal wire exit (37%) followed by balloon dilation catheters (28%). Covered stents were used to treat 25% of perforations, with emergency cardiac surgery needed in 17%.

Conclusion

Coronary perforations occurs in approximately 1 in 250 all-comer PCI procedures. A tendency towards increase in coronary perforations is likely reflective of contemporary trends towards high pressure post-dilatation with 1:1 vessel sizing as well as an ageing population with increasingly complex, calcific coronary disease. However, reduction in CAP related mortality suggests earlier recognition and effective treatment with transcatheter techniques.

Funding Acknowledgement

Type of funding sources: None.

System cost minimisation in hybrid energy storage systems connected to microgrids: A comparative approach

Electricity is the most critical facility for humans. All traditional energy supplies are rapidly depleting. As a result, the energy resources are moved from traditional to non-conventional. In this research, mixture of two energy tools, namely wind and solar energy are used. Using a Hybrid Energy Storage System (HESS), continuous power can be provided. Electricity can be produced at a cost that is affordable. The integration of solar and wind in a hybrid system cause an increase in the system’s stability, which is the key benefit of this research. The system’s power transmission efficiency and reliability can be greatly enhanced by integrating these two intermittent sources. When one of the energy source is unavailable or inadequate to meet load demands, the other energy source will supply the power. The major contribution in this research is that, the proposed bidirectional single-inductor multiple-port (BSIMP) converter significantly lowers the component count, smaller circuit size and lower cost, allowing HESS to be integrated into DC microgrid. Minimum number of components are used for the same number of ESs in HESS in the proposed BSIMP converter. The hybridization of battery and supercapacitor (SC) for storage purpose is more cost effective, as compared to the battery energy storage system, thus improving the battery stress and hence used for large scale grid energy storage. SC’s are accepted as backup and found very useful in delivering high power, not possible with batteries. The use of SC in addition to batteries can be one solution for achieving the low life cycle economy. The Single Objective Adaptive Firefly Algorithm (SOAFA) is introduced for optimising the Proportional-Integral (PI) controller parameters. The system cost is reduced by about 32%, with the constraints on wind turbine swept area, PV area, total battery and SC capacity with the proposed optimisation algorithm.

The role of cardio-protective agents in breast cancer patients to prevent anthracycline induced cardiotoxicity: a systematic review and network meta-analysis

Background

Anthracycline (ANT)-based chemotherapy for breast malignancies have significantly improved cancer outcomes. However, the cardiotoxicity induced by ANTs in the breast cancer population has increased major adverse cardiac events. While randomised controlled trials (RCTs) have explored different primary preventative agents to confer cardio-protection pre chemotherapy, comparisons between agents has been limited. It is unclear which drug is the most efficacious in preserving Left Ventricular Ejection Fraction (LVEF) amongst this population.

Purpose

To perform a network meta-analysis of RCTs comparing the impact on LVEF of various prophylactic cardio-protective agents, when prescribed to breast cancer patients prior to ANT-based chemotherapy.

Methods

Two independent authors performed a literature search as per the PRISMA guidelines using four databases (CENTRAL, Cochrane Reviews, MEDLINE, SCOPUS), to find RCTS evaluating cardio protective agents. The trial population was limited to patients with breast cancer without prior ANT exposure. Trials were only included if the cardio-protective agents were commenced prior to ANT dosing. The assessed outcome was a mean change in LVEF pre and post ANT dosing, compared to placebo prevention. Extracted data included age, ANT dose, and LVEF pre and post chemotherapy. The Cochrane Risk of Bias tool was used to appraise included RCTs.

Results

From 2807 search results, we identified twelve RCTs which evaluated 1126 patients. Seven studies assessed beta-blockers alone and two assessed combination ACE inhibitors and beta blockers. Individual studies assessing ACE inhibitors, spironolactone or rosuvastatin alone were also included. All patients were female with an average age of 50.5 and average ANT dose of 412 mg/m2. Our network meta-analysis showed beta-blockers showed significant protection with higher LVEF than placebo by 2.38% [0.52, 4.25]. ACE inhibitors showed a similar magnitude of LVEF preservation 2.59% [−0.20, 5.38] but not statistically significant due to wider CI because of lower sample size (n=250). Spironolactone showed a statistically significant preservation in LVEF by 12.80% [3.44, 22.16], however this was based on a single study (n=83), with marked measurement bias and deviations from intended intervention. All included trials had an intermediate or high risk of bias, with marked heterogeneity in ANT dosing and LVEF monitoring.

Conclusion

Beta-blockers minimise LVEF decline when administered prior to anthracycline chemotherapy, compared against alternate agents. Data may be underpowered to demonstrate the benefit of ACE inhibitor and combination beta blocker/ACE inhibitor prescription. The quality of RCT data to date is limited by a high risk of bias and significant heterogeneity between RCA reporting. This analysis is likely to inform clinical practice, and allow clinicians to prescribe primary cardio-protection in patients at high risk of cardiotoxicity.

Funding Acknowledgement

Type of funding source: None