Peri-Infarct Quantification by Cardiac Magnetic Resonance to Predict Outcomes in Ischemic Cardiomyopathy

Background:

In ischemic cardiomyopathy, cardiac magnetic resonance assessment of the peri-infarct zone, a potential substrate for arrhythmogenesis, may serve as a novel prognosticator and guide the optimal use of implantable cardioverter-defibrillators. We undertook a systematic review and meta-analysis assessing the prognostic value of the peri-infarct zone on late gadolinium enhancement cardiac magnetic resonance in ischemic cardiomyopathy.

Methods:

We searched MEDLINE (Medical Literature Analysis and Retrieval System Online), EMBASE (Medical Literature Analysis and Retrieval System Online), and CENTRAL (Medical Literature Analysis and Retrieval System Online) from inception to January 2019 for prognostic studies relating peri-infarct size with clinical outcomes in ischemic cardiomyopathy. Two authors independently performed study selection and data extraction. Pooled effect estimates were calculated with random effects models, risk of bias and strength of evidence were assessed by the Quality in Prognostic Studies tool and Grading of Recommendations Assessment, Development, and Education, respectively.

Results:

Twenty studies were eligible, representing 14 cohort studies (n=1518) with mean follow-up of 3.6 years and 6 cross-sectional studies (n=189). The extent of the peri-infarct zone was significantly predictive of all-cause mortality (3 studies; n=539; hazard ratio, 1.34/10 g [95% CI, 1.13–1.59]; I 2 =0%; high-quality evidence), appropriate implantable cardioverter-defibrillator therapy (5 studies; n=361; hazard ratio, 1.31/10 g [95% CI, 1.17–1.47]; I 2 =0%; high-quality evidence), and inducibility of ventricular tachycardia on electrophysiological study (5 studies; n=167; OR, 2.63/g [95% CI, 1.39–4.96]; I 2 =14%; low-quality evidence). After adjusting for age and left ventricular ejection fraction, the peri-infarct zone, as a percentage of total infarct size, remained an independent predictor of all-cause mortality (2 studies; n=445; hazard ratio, 1.29/10% [95% CI, 1.15–1.44]; I 2 =0%; high-quality evidence).

Conclusions:

There is limited but consistent evidence that quantification of the peri-infarct zone predicts long-term mortality and appropriate implantable cardioverter-defibrillator therapy in ischemic cardiomyopathy. Future studies should confirm whether late gadolinium enhancement-cardiac magnetic resonance assessment may improve implantable cardioverter-defibrillator treatment decisions.

Clinical Trial Registration:

URL: https://www.crd.york.ac.uk/prospero/ . Unique identifier: CRD42017077337.

P1932Predictors of DAPT use in patients beyond 1 year post myocardial infarction: Insights from the TIGRIS observational study

Background

International guidelines vary in their recommendations for dual antiplatelet therapy (DAPT) use beyond 1 year post-myocardial infarction (MI).

Purpose

To identify predictors of DAPT use in patients ≥1 year post-MI prior to the publication of the DAPT score and the 2017 European Society of Cardiology (ESC) guidelines for DAPT in coronary artery disease.

Methods

TIGRIS (NCT01866904) was a prospective, multi-center (369 centers in 25 countries), observational study of patients 1 to 3 years post-MI between June 2013 and November 2014. We performed a multivariable logistic regression analysis to identify independent predictors of DAPT use at 396 days post-MI (365 + 31 days overrun period to allow intended DAPT discontinuation at 1 year). Patients on oral anticoagulation were excluded.

Results

Of 8464 patients enrolled (mean age 66 years, women 24%, ST-elevation MI 53%), 40% were on DAPT at 396 days post-MI (Figure). In the subset of patients on DAPT at 396 days post-MI, aspirin was combined with clopidogrel in 84%, prasugrel in 12%, and other antiplatelet agents in 4%. DAPT use at 396 days post-MI was independently associated with geographic region, age, PCI for the index MI, and a history of multivessel disease or angina (Table). Several variables included in the DAPT score and ESC guideline recommendations (diabetes, second prior MI, hypertension, peripheral artery disease, heart failure, smoking, and renal insufficiency) were not independent predictors of DAPT use at 396 days.

Independent predictors of DAPT @396 days Variable at enrolment Patients Odds ratio (95% CI) P-value Region: Europe 3813 Reference group 0.01 North America 923 1.65 (0.56, 4.86) Latin America 1084 2.55 (1.19, 5.47) Asia and Australia 2644 3.01 (1.42, 6.36) Age <65 years 3274 1.15 (1.04, 1.28) 0.005 PCI for index MI 6925 2.08 (1.82, 2.38) <0.0001 Multi-vessel disease 5598 1.37 (1.24, 1.52) <0.0001 History of angina 829 1.46 (1.24, 1.71) <0.0001

DAPT use at 396 days post-MI by region

Conclusion

During the study period, DAPT use ≥1 year post-MI was prevalent and appeared to be influenced by regional practices. Further research is needed to determine whether the DAPT score and the 2017 ESC guidelines for dual antiplatelet therapy have changed long-term DAPT use practices.

Acknowledgement/Funding

AstraZeneca AB, Södertälje, Sweden

P317A novel role of SGLT2 inhibitors to increase circulating proangiogenic progenitor cells in patients with type 2 diabetes and cardiovascular disease: A sub-study of the EMPA-HEART CardioLink-6 Trial

Background

SGLT2 inhibitors (SGLT2i) have been demonstrated to reduce major adverse cardiovascular events and mortality in patients with type 2 diabetes (T2D) who are at high risk for cardiovascular disease (CVD). However, the mechanism(s) of the underlying benefit remain unclear. Since regenerative cell exhaustion resulting in impaired vascular homeostasis has been proposed as a key driver of CV events in T2D, we hypothesised that modulation of circulating vascular regenerative cell content by SGLT2i may be a novel basis of cardioprotection.

Purpose

To evaluate the effects of the SGLT2i, empagliflozin (EMPA), vs placebo on circulating vascular regenerative and pro-inflammatory cells in patients with T2D and CVD.

Methods

This was a biomarker sub-study of the EMPA-HEART Cardiolink-6 randomised trial of EMPA (10mg QD) vs placebo in patients with T2D and a history of coronary artery disease (prior myocardial infarction and/or coronary revascularisation). Blood samples (baseline N=48; study end N=26) underwent multiparametric progenitor cell analyses by flow cytometry. Circulating cells were assessed for aldehyde dehydrogenase (ALDH) activity, a self-protective enzyme highly expressed in several proangiogenic progenitor cell lineages, as well as cell surface co-expression of the primitive progenitor (CD34, CD133) or M1/M2 macrophage (CD80, CD163) markers.

Results

Individuals with increased inflammatory burden (ALDHhi granulocytes above the baseline median) were older (61±2 vs 67±2 years), more likely to be current or past smokers (21% vs 42%) and had reduced LV function, assessed by echocardiography. The placebo- and EMPA-assigned groups were equivalent at baseline with respect to the frequency and distribution of proangiogenic progenitor cells (ALDHhiSSClo), monocyte/macrophage (ALDHhiSSCmid) and inflammatory granulocyte (ALDHhiSSChi) precursors. Following 6-months of treatment with EMPA, there was a marked increase in the number of circulating primitive ALDHhiSSClo cells with CD133 (Placebo: −2.8±3.8%, EMPA: +8.6±2.5%, P<0.02) or CD133/CD34 (Placebo: 0.4±4.5%, EMPA: +13.3±3.8%, P<0.05) co-expression. Furthermore, EMPA treatment was associated with an increase in the frequency of circulating anti-inflammatory cells with M2 macrophage polarisation marked by CD163 (Placebo: −0.7±0.8%, EMPA = +3.9±1.3%, P<0.01) expression. Non-significant increases in circulating proangiogenic monocytes, and decreases in the frequency of circulating inflammatory granulocytes were also observed after EMPA treatment (vs placebo).

Conclusion

We provide the first evidence showing that SGLT2i treatment with EMPA alters the balance of key circulating vascular progenitor and inflammatory cells in patients with T2D and CVD. We suggest that SGLT2i may afford cardioprotection through a novel and previously unrecognised capacity to limit regenerative cell exhaustion in T2D.

Acknowledgement/Funding

This trial was supported by an unrestricted investigator-initiated study grant from Boehringer Ingelheim.

P3753Does empagliflozin modulate the autonomic system among patients with type 2 diabetes and coronary artery disease? Insights from the Holter sub-study of the EMPA-Heart CardioLink-6 Randomised Trial

Introduction

The mechanism behind how empagliflozin, a sodium-glucose co-transporter 2 (SGLT2) inhibitor, reduces all-cause and cardiovascular mortality among patients with type 2 diabetes (T2DM) and coronary artery disease (CAD) is unknown. Autonomic tone, as reflected by changes in heart rate variability (HRV), is an established prognosticator in patients with CAD and/or heart failure.

Purpose

To assess if empagliflozin treatment changes HRV in subjects with T2DM and CAD.

Methods

In the double-blind EMPA-Heart trial, 97 subjects with T2DM and CAD were randomised to empagliflozin 10 mg/day or placebo for 6 months and underwent 24-hour Holter monitoring at baseline and 6 months. Using automated algorithms, time and frequency HRV domain measures were obtained (standard deviation of NN intervals (SDNN); SD of the average NN intervals for each 5-minute segment (SDANN); root mean square of successive RR interval differences (rMSSD); % interval differences of successive NN intervals >50 ms (pNN50); ratio of low to high frequency (LF/HF)). Changes of these HRV parameters were calculated over 6 months. Between-group differences in HRV parameters were compared using ANCOVA.

Results

Complete Holter data (baseline and 6-month) were available for 68% (n=66) of the cohort. The average heart rate (HR) at baseline/6 months was 69.5±9.8 bpm/72.8±8.1 bpm and 76±10.4 bpm/76.5±10.6 in the placebo group and empagliflozin group, respectively. Both groups had similar changes in average HR over 6 months. Key Holter data are summarised in the table. SDNN and SDANN were higher in the placebo vs. empagliflozin group at 6 months; no significant difference was noted for all other measures.

Empagliflozin 10 mg/day (n=33) Placebo (n=33) Adjusted difference between Empagliflozin and Placebo (ANCOVA) Baseline, Mean (SD) 6-month, Mean (SD) Baseline, Mean (SD) 6-month, Mean (SD) Mean, (95% CI) P-value SDNN (ms) 100.49 (43.74) 98.05 (38.86) 109.35 (30.02) 125.08 (43.83) −18.55 (−34.28, −2.82) 0.022 SDANN (ms) 86.84 (39.34) 83.76 (35.53) 94.70 (28.52) 118.28 (77.41) −20.24 (−37.27, −3.21) 0.021 rMSSD (ms) 27.00 (11.84) 27.22 (13.48) 28.00 (11.58) 27.17 (9.38) −1.23 (−6.02, 3.55) 0.608 pNN50 (%) 7.81 (7.59) 8.32 (9.51) 8.26 (7.8) 6.93 (5.35) 0.51 (−2.61, 3.62) 0.746 LF/HF ratio 1.63 (0.52) 1.65 (0.51) 1.53 (0.43) 1.83 (0.82) −0.08 (−0.38, 0.22) 0.602

Conclusions

Among subjects with T2DM and CAD, changes in HRV over 6 months were similar in the empagliflozin and placebo arms suggesting that the mortality benefit conferred by empagliflozin is not associated with positive modulation of autonomic tone.

Acknowledgement/Funding

This trial was supported by an unrestricted investigator-initiated study grant from Boehringer Ingelheim.

SGLT2 Inhibition with Empagliflozin Increases Circulating Provascular Progenitor Cells in People with Type 2 Diabetes Mellitus

Hess et al. quantified circulating aldehyde dehydrogenase-expressing (ALDH^hi) cell subsets in people with T2DM given either empagliflozin (EMPA) or placebo. EMPA treatment increased circulating pro-angiogenic CD133⁺ progenitor cells, decreased pro-inflammatory ALDH^hi granulocyte precursors, and increased ALDH^hi monocytes with M2 polarization. EMPA treatment improved T2DM-associated "regenerative cell depletion" contributing to enhanced vascular health.

Association between conversion to in-center nocturnal hemodialysis and right ventricular remodeling

Background

In-center nocturnal hemodialysis (INHD) is associated with favorable left ventricular (LV) remodeling. Although right ventricular (RV) structure and function carry prognostic significance, the impact of dialysis intensification on RV is unknown. Our objectives were to evaluate changes in RV mass index (MI), end-diastolic volume index (EDVI), end-systolic volume index (ESVI) and ejection fraction (EF) after conversion to INHD and their relationship with LV remodeling.

Methods

Of 67 conventional hemodialysis (CHD, 4 h/session, three times/week) patients, 30 continued on CHD and 37 converted to INHD (7-8 h/session, three times/week). Cardiac magnetic resonance imaging was performed at baseline and 1 year using a standardized protocol; an experienced and blinded reader performed RV measurements.

Results

At 1 year there were significant reductions in RVMI {-2.1 g/m2 [95% confidence interval (CI) -3.8 to - 0.4], P = 0.017}, RVEDVI [-9.5 mL/m2 (95% CI - 16.3 to - 2.6), P = 0.008] and RVESVI [-6.2 mL/m2 (95% CI - 10.9 to - 1.6), P = 0.011] in the INHD group; no significant changes were observed in the CHD group. Between-group comparisons showed significantly greater reduction of RVESVI [-7.9 mL/m2 (95% CI - 14.9 to - 0.9), P = 0.03] in the INHD group, a nonsignificant trend toward greater reduction in RVEDVI and no significant difference in RVMI and RVEF changes. There was significant correlation between LV and RV in terms of changes in mass index (MI) (r = 0.46), EDVI (r = 0.73), ESVI (r = 0.7) and EF (r = 0.38) over 1 year (all P < 0.01).

Conclusions

Conversion to INHD was associated with a significant reduction of RVESVI. Temporal changes in RV mass, volume and function paralleled those of LV. Our findings support the need for larger, longer-term studies to confirm favorable RV remodeling and determine its impact on clinical outcomes.

Evaluation of the impact of the GRACE risk score on the management and outcome of patients hospitalised with non-ST elevation acute coronary syndrome in the UK: protocol of the UKGRIS cluster-randomised registry-based trial

INTRODUCTION

For non-ST-segment elevation acute coronary syndrome (NSTEACS) there is a gap between the use of class I guideline recommended therapies and clinical practice. The Global Registry of Acute Coronary Events (GRACE) risk score is recommended in international guidelines for the risk stratification of NSTEACS, but its impact on adherence to guideline-indicated treatments and reducing adverse clinical outcomes is unknown. The objective of the UK GRACE Risk Score Intervention Study (UKGRIS) trial is to assess the effectiveness of the GRACE risk score tool and associated treatment recommendations on the use of guideline-indicated care and clinical outcomes.

METHODS AND ANALYSIS

The UKGRIS, a parallel-group cluster randomised registry-based controlled trial, will allocate hospitals in a 1:1 ratio to manage NSTEACS by standard care or according to the GRACE risk score and associated international guidelines. UKGRIS will recruit a minimum of 3000 patients from at least 30 English National Health Service hospitals and collect healthcare data from national electronic health records. The co-primary endpoints are the use of guideline-indicated therapies, and the composite of cardiovascular death, non-fatal myocardial infarction, new onset heart failure hospitalisation or cardiovascular readmission at 12 months. Secondary endpoints include duration of inpatient hospital stay over 12 months, EQ-5D-5L responses and utilities, unscheduled revascularisation and the components of the composite endpoint over 12 months follow-up.

ETHICS AND DISSEMINATION

The study has ethical approval (North East - Tyne & Wear South Research Ethics Committee reference: 14/NE/1180). Findings will be announced at relevant conferences and published in peer-reviewed journals in line with the funder's open access policy.

TRIAL REGISTRATION NUMBER

ISRCTN29731761; Pre-results.

Effect of Empagliflozin on Left Ventricular Mass in Patients With Type 2 Diabetes Mellitus and Coronary Artery Disease: The EMPA-HEART CardioLink-6 Randomized Clinical Trial

BACKGROUND

SGLT2 (sodium-glucose cotransporter 2) inhibitors lower cardiovascular events in type 2 diabetes mellitus but whether they promote direct cardiac effects remains unknown. We sought to determine if empagliflozin causes a decrease in left ventricular (LV) mass in people with type 2 diabetes mellitus and coronary artery disease.

METHODS

Between November 2016 and April 2018, we recruited 97 individuals ≥40 and ≤80 years old with glycated hemoglobin 6.5% to 10.0%, known coronary artery disease, and estimated glomerular filtration rate ≥60mL/min/1.73m². The participants were randomized to empagliflozin (10 mg/day, n=49) or placebo (n=48) for 6 months, in addition to standard of care. The primary outcome was the 6-month change in LV mass indexed to body surface area from baseline as measured by cardiac magnetic resonance imaging. Other measures included 6-month changes in LV end-diastolic and -systolic volumes indexed to body surface area, ejection fraction, 24-hour ambulatory blood pressure, hematocrit, and NT-proBNP (N-terminal pro b-type natriuretic peptide).

RESULTS

Among the 97 participants (90 men [93%], mean [standard deviation] age 62.8 [9.0] years, type 2 diabetes mellitus duration 11.0 [8.2] years, estimated glomerular filtration rate 88.4 [16.9] mL/min/1.73m², LV mass indexed to body surface area 60.7 [11.9] g/m²), 90 had evaluable imaging at follow-up. Mean LV mass indexed to body surface area regression over 6 months was 2.6 g/m² and 0.01 g/m² for those assigned empagliflozin and placebo, respectively (adjusted difference -3.35 g/m²; 95% CI, -5.9 to -0.81g/m², P=0.01). In the empagliflozin-allocated group, there was significant lowering of overall ambulatory systolic blood pressure (adjusted difference -6.8mmHg, 95% CI -11.2 to -2.3mmHg, P=0.003), diastolic blood pressure (adjusted difference -3.2mmHg; 95% CI, -5.8 to -0.6mmHg, P=0.02) and elevation of hematocrit (P=0.0003).

CONCLUSIONS

Among people with type 2 diabetes mellitus and coronary artery disease, SGLT2 inhibition with empagliflozin was associated with significant reduction in LV mass indexed to body surface area after 6 months, which may account in part for the beneficial cardiovascular outcomes observed in the EMPA-REG OUTCOME (BI 10773 [Empagliflozin] Cardiovascular Outcome Event Trial in Type 2 Diabetes Mellitus Patients) trial.

CLINICAL TRIAL REGISTRATION

URL: https://www.clinicaltrials.gov. Unique identifier: NCT02998970.

Prolonged P wave duration is associated with right atrial dimensions, but not atrial arrhythmias, in middle-aged endurance athletes

BACKGROUND

Atrial arrhythmias occur at a higher than expected prevalence amongst endurance athletes. Few studies have examined both atrial structure and arrhythmias in middle-aged endurance athletes. We examined the relationship between P-wave duration, atrial dimensions, and the presence of atrial ectopy in long-standing, middle-aged endurance athletes.

METHODS

Middle-aged athletes with a minimum of 10 years of competitive endurance sport history and no history of structural heart disease or clinical atrial arrhythmias, had 12-lead ECGs to assess P-wave duration, signal-averaged ECGs (SAECG) to assess filtered P-wave duration, a 24 h Holter monitor to assess atrial ectopy, and echocardiography and cardiac magnetic resonance imaging to assess atrial structural characteristics.

RESULTS

Amongst endurance athletes (n = 104; mean age = 54 ± 5 years; 63% male), filtered P-wave duration on SAECG was correlated with P-wave duration on 12-lead ECG (r = 0.36, p, 0.0001), as well as with larger CMR-derived RA areas (r = 0.30, p = 0.01) and volumes (r = 0.24, p < 0.05). There was no correlation between filtered P-wave duration and any LA measures on imaging (p > 0.05). There was no correlation between the incidence of atrial ectopy (premature atrial contractions or atrial tachycardia) and any electrocardiographic or structural measures.

CONCLUSION

Longer filtered P-wave duration was associated with larger RA areas and volumes, without an increase in atrial ectopy.

Growth differentiation factor 15 is decreased by kidney transplantation

BACKGROUND

Growth differentiation factor 15 (GDF15) is markedly increased in end-stage kidney disease and has been related to increased mortality in patients on dialysis. We hypothesized that kidney transplantation would decrease both GDF15 and N-terminal pro-B-type natriuretic peptide (NT-proBNP) and that GDF-15 decrease relates to post-kidney transplantation allograft function.

METHODS

End-stage kidney disease patients on dialysis awaiting a living donor kidney transplantation (n = 39), and those expected to be on the deceased donor waitlist for at least 12 months (n = 43) were enrolled at three transplant centers. Serum GDF15 and NT-proBNP were measured at 0, 3, and 12 months post-kidney transplantation or post-enrollment. Change in serum GDF15 and NT-proBNP concentrations, and their relation to estimated glomerular filtration rate (eGFR) were assessed by non-parametric tests and regression analyses.

RESULTS

Median baseline GDF15 was 4744 pg/ml and 5451 pg/ml for the kidney transplantation and dialysis groups, respectively (p = 0.09). Kidney transplantation resulted in a significant decrease in GDF15 (month 12 median 1631 pg/ml, p < 0.0001 vs. baseline), whereas there was no change for the dialysis group (month 12 median 5658 pg/ml, p = 0.31). Post-kidney transplantation NT-proBNP highly correlated with GDF15 (ρ = 0.64, p < 0.0001). GDF15 inversely correlated with post-transplant eGFR for the kidney transplantation group (ρ = -0.42, p = 0.0081). Month 12 NT-proBNP explained 15.8% and 40.1% of the variance in month 12 GDF15 in the dialysis and kidney transplantation groups, respectively. The relationship of GDF15 with eGFR was no longer significant when NT-proBNP was included in the models.

CONCLUSIONS

Kidney transplantation significantly decreases serum GDF15 concentrations. The post-kidney transplantation association of GDF15 with NT-proBNP is consistent with a gradient of post- kidney transplantation cardiovascular risk.

Assessment of left ventricular function by CMR versus MUGA scans in breast cancer patients receiving trastuzumab: a prospective observational study

Little is known about the comparison of multiple-gated acquisition (MUGA) scanning with cardiovascular magnetic resonance (CMR) for serial monitoring of HER2+ breast cancer patients receiving trastuzumab. The association of cardiac biomarkers with CMR left ventricular (LV) function and volume is also not well studied. Our objectives were to compare CMR and MUGA for left ventricular ejection fraction (LVEF) assessment, and to examine the association between changes in brain natriuretic peptide (NT-BNP) and troponin-I and changes in CMR LV function and volume. This prospective longitudinal two-centre cohort study recruited HER2+ breast cancer patients between January 2010 and December 2013. MUGA, CMR, NT-BNP and troponin-I were performed at baseline, 6, 12, and 18 months after trastuzumab initiation. In total, 41 patients (age 51.7 ± 10.8 years) were enrolled. LVEF comparison between MUGA and CMR demonstrated weak agreement (Lin's correlation coefficient r = 0.46, baseline; r = 0.29, 6 months; r = 0.42, 12 months; r = 0.39, 18 months; all p < 0.05). Bland-Altman plots demonstrated wide LVEF agreement limits (pooled agreement limits 3.0 ± 6.2). Both modalities demonstrated significant LVEF decline at 6 and 12 months from baseline, concomitant with increased LV volumes on CMR. Changes in NT-BNP correlated with changes in LV diastolic volume at 12 and 18 months (p < 0.05), and LV systolic volume at 18 months (p < 0.05). Changes in troponin-I did not correlate with changes in LV function or volume at any timepoint. In conclusion, CMR and MUGA LVEF are not interchangeable, warranting selection and utility of one modality for serial monitoring. CMR is useful due to less radiation exposure and accuracy of LV volume measurements. Changes in NT-BNP correlated with changes in LV volumes.

Underuse of ECG monitoring in oncology patients receiving QT-interval prolonging drugs

OBJECTIVE

We examined use of ECG monitoring in oncology patients prescribed QT-prolonging drugs.

METHODS

Patients ≥66 years diagnosed with cancer between 2005 and 2011 were identified through the Ontario Cancer Registry and linked to multiple population-based administrative databases to ascertain demographics, comorbidities, prescription drug use, systemic therapy and ECG. QT-prolonging drugs were identified as per drug lists developed by the Arizona Center for Education and Research on Therapeutics. Univariable and multivariable analyses were used to examine factors associated with ECG use in patients on first-line systemic therapy.

RESULTS

A total of 48 236 patients (median age 74; 49% women) received one or more drugs associated with a risk of QT-interval prolongation but only 27% of patients had an ECG performed. Factors associated with more ECG use on multivariable analysis included recent cancer diagnosis (p for trend <0.001 between 2005 and 2011), use of concurrent QT-prolonging drugs (OR=1.15 per each additional QT-prolonging drug, 95% CI 1.12 to 1.17) and the presence of coronary artery disease (OR 1.31; 95% CI 1.25 to 1.38) and heart failure (OR 1.25; 95% CI 1.17 to 1.35). Use of anticancer (OR 0.74; 95% CI 0.70 to 0.79) and antiemetic (OR 0.93; 95% CI 0.88 to 0.99) QT-prolonging drugs was paradoxically associated with less ECG use.

CONCLUSIONS

Our study highlights common use of QT-prolonging drugs and underuse of ECG in oncology patients. Since ECG is an inexpensive, non-invasive and widely available test, it may be readily incorporated in the monitoring of patients for toxicities in routine clinical practice.

Comparison of outcomes in a population-based cohort of women with metastatic breast cancer receiving anti-HER2 therapy with clinical trial outcomes

1037

Background: Little data exist for comparing cardiac safety and survival outcomes of anti-HER2 therapy with concurrent trastuzumab (T) and pertuzumab (P) or ado-T emtansine (TDM1) in metastatic breast cancer (MBC) patients enrolled in randomized clinical trial (RCT) vs those in the real world. Furthermore, whether older patients have worse outcomes is unknown. Methods: This was a retrospective population-based cohort of all women with MBC treated with concurrent T with P or TDM1 in Ontario (between 2012 and 2017), identified from New Drug Funding Program and linked to Ontario Cancer Registry and other administrative datasets. Outcomes were incident heart failure (HF, defined as hospitalization or emergency room visit for HF) and overall survival (OS). RCT data were obtained from digitizing survival curves as per established methods and compared with cohort OS data using log-rank test. Age based comparison of outcomes was conducted for women ≥ 65 years old vs younger. Results: Our cohort composed of 833 (28% > 64 years old), and 397 (28% > 64 years old) women treated with P and TDM1, respectively, of which 46 and 30 had baseline HF, respectively. 49% and 99.5% of women received T prior to P and TDM1, respectively. Incident HF following P or TDM1 initiation was low (P 26 women, TDM1 8 women; Table). HF events was not more in women ≥ 65 years old compared to women < 65 treated with P (16 vs. 10, p = 0.23). Unadjusted OS was significantly worse than RCT OS (Table; P HR 1.67, 95% CI 1.37-2.03, p < 0.0001; TDM1 HR 2.80, 95% CI 2.27-3.44, p < 0.0001). Older women had worse OS than younger women for P (HR 1.54, 95% CI 1.22-1.96, p = 0.0003), but not for TDM1 (HR 1.08, 95% CI 0.81-1.43, p = 0.62). Conclusions: HF incidence during P or TDM1 therapy in this real world cohort was relatively low. Survival in this cohort was significantly worse compared to RCT, particularly for older women, suggesting importance of evaluating effectiveness in an unselected patient population to facilitate informed decision-making based on real-world risks and survival outcomes.[Table: see text]

Serial Measurements of Left Ventricular Systolic and Diastolic Function by Cardiac Magnetic Resonance Imaging in Patients with Early Stage Breast Cancer on Trastuzumab

Our aim was to evaluate the temporal changes in left ventricular (LV) diastolic filling in relation to other LV parameters using cardiac MRI (CMR) in patients with HER2 positive breast cancer receiving trastuzumab therapy. Fourty-one women with early stage HER2+ breast cancer underwent serial CMR (baseline, 6, 12, and 18 months) after initiation of trastuzumab therapy. A single, blinded observer measured LV parameters on de-identified CMRs in random order. Linear mixed models were used to investigate temporal changes. Compared to baseline, there were significant decreases in systolic function as measured by both left ventricular ejection fraction (LVEF) (p <0.001 at 6 and 12 months) and peak ejection rate corrected for end-diastolic volume (PER/LVEDV) (p = 0.008 at 6 months, p = 0.01 at 12 months). However, these differences were no longer significant at 18 months. In contrast, significant reductions in diastolic function as measured by LV peak filling rate corrected for end-diastolic volume (PFR/LVEDV) were observed at 6 months (p = 0.012), 12 months (p = 0.031), and up to 18 months (p = 0.034). There were no significant temporal changes in the time to peak filling rate corrected for cardiac cycle (TPF/RR). The reduction in PFR/LVEDV at 18 months was no longer significant when corrected for heart rate. In conclusion, there were significant subclinical deleterious effects on both LV systolic and diastolic function among patients receiving trastuzumab. While there was recovery in LV systolic function after therapy cessation at 18 months, reduction in PFR/LVEDV appeared to persist. Thus, diastolic dysfunction may serve as a marker of trastuzumab-induced cardiotoxicity that needs to be confirmed in a larger study.

Prevalence of Thiamin Deficiency in Ambulatory Patients with Heart Failure

BACKGROUND

Thiamin is a required coenzyme in energy production reactions that fuel myocardial contraction. Therefore, thiamin deficiency (TD) may aggravate cardiac dysfunction in patients with systolic heart failure (HF).

OBJECTIVE

To determine the prevalence of TD in ambulatory participants with HF as well as the relationships between thiamin status and HF severity, dietary thiamin intake, diuretic use, and circulating neurohormones.

DESIGN

A cross-sectional study comparing the prevalence of TD in ambulatory patients with HF with that of controls. Demographic, anthropometric, nutrition, medication use, and heart function data were collected from direct interviewing, questionnaires, and medical records. Blood samples were obtained to measure levels of neurohormones and assess TD.

PARTICIPANTS/SETTING

Fifty age-matched control participants without HF and 100 outpatients with HF and reduced left ventricular function were recruited from clinics at St Michael's Hospital, University Health Network and Mount Sinai Hospital, Toronto, Ontario, Canada, between September 2009 and February 2011.

MAIN OUTCOME MEASURES

To assess TD, erythrocyte thiamin pyrophosphate (TPP) was measured using high-performance liquid chromatography. TD was defined as TPP<6.07 μg/dL (180 nmol/L).

STATISTICAL ANALYSES PERFORMED

Prevalence rates were analyzed using χ² test. Nonparametric statistics (Jonckheere-Terpstra, Kruskal-Wallis, Spearman's correlation) were used to assess TPP levels in relation to HF severity, medication use and plasma concentrations of F2-isoprostanes, norepinephrine, and N-terminal pro-brain natriuretic peptide (NT-proBNP).

RESULTS

There was no significant difference in the prevalence of TD in outpatients with HF (6%) and controls (6%) (P=0.99). No relationship was found between heart function, thiamin intake, use or dose of diuretics, and TD. A positive relationship was observed between erythrocyte TPP and F2-isoprostane levels (r_s=0.22, P=0.03) but not between erythrocyte TPP and norepinephrine (P=0.45) and NT-proBNP (P=0.58).

CONCLUSION

The prevalence of TD was low in ambulatory HF participants suggesting that, unlike hospitalized patients, ambulatory patients may be at a low risk for TD.

Cardiovascular magnetic resonance left ventricular strain in end-stage renal disease patients after kidney transplantation

BACKGROUND

Cardiovascular disease is a significant cause of morbidity and mortality in patients with end-stage renal disease (ESRD) and kidney transplant (KT) patients. Compared with left ventricular (LV) ejection fraction (LVEF), LV strain has emerged as an important marker of LV function as it is less load dependent. We sought to evaluate changes in LV strain using cardiovascular magnetic resonance imaging (CMR) in ESRD patients who received KT, to determine whether KT may improve LV function.

METHODS

We conducted a prospective multi-centre longitudinal study of 79 ESRD patients (40 on dialysis, 39 underwent KT). CMR was performed at baseline and at 12 months after KT.

RESULTS

Among 79 participants (mean age 55 years; 30% women), KT patients had significant improvement in global circumferential strain (GCS) (p = 0.007) and global radial strain (GRS) (p = 0.003), but a decline in global longitudinal strain (GLS) over 12 months (p = 0.026), while no significant change in any LV strain was observed in the ongoing dialysis group. For KT patients, the improvement in LV strain paralleled improvement in LVEF (57.4 ± 6.4% at baseline, 60.6% ± 6.9% at 12 months; p = 0.001). For entire cohort, over 12 months, change in LVEF was significantly correlated with change in GCS (Spearman's r = - 0.42, p < 0.001), GRS (Spearman's r = 0.64, p < 0.001), and GLS (Spearman's r = - 0.34, p = 0.002). Improvements in GCS and GRS over 12 months were significantly correlated with reductions in LV end-diastolic volume index and LV end-systolic volume index (all p < 0.05), but not with change in blood pressure (all p > 0.10).

CONCLUSIONS

Compared with continuation of dialysis, KT was associated with significant improvements in LV strain metrics of GCS and GRS after 12 months, which did not correlate with blood pressure change. This supports the notion that KT has favorable effects on LV function beyond volume and blood pessure control. Larger studies with longer follow-up are needed to confirm these findings.

Determinants of Left Ventricular Characteristics Assessed by Cardiac Magnetic Resonance Imaging and Cardiovascular Biomarkers Related to Kidney Transplantation

Background:

Cardiac magnetic resonance (CMR) imaging accurately and precisely measures left ventricular (LV) mass and function. Identifying mechanisms by which LV mass change and functional improvement occur in some end-stage kidney disease (ESKD) patients may help to appropriately target kidney transplant (KT) recipients for further investigation and intervention. The concentration of serum adiponectin, a cardiovascular biomarker, increases in cardiac failure, its production being enhanced by B-type natriuretic peptide (BNP), and both serum adiponectin and BNP concentrations decline posttransplantation.

Objective:

We tested the hypothesis that kidney transplantation alters LV characteristics that relate to serum adiponectin concentrations.

Design:

Prospective and observational cohort study.

Setting:

The study was performed at 3 adult kidney transplant and dialysis centers in Ontario, Canada.

Patients:

A total of 82 KT candidate subjects were recruited (39 to the KT group and 43 to the dialysis group). Predialysis patients were excluded.

Measurements:

Subjects underwent CMR with a 1.5-tesla whole-body magnetic resonance scanner using a phased-array cardiac coil and retrospective vectorographic gating. LV mass, LV ejection fraction (LVEF), LV end-systolic volume (LVESV), and LV end-diastolic volume (LVEDV) were measured by CMR pre-KT and again 12 months post-KT (N = 39), or 12 months later if still receiving dialysis (N = 43). LV mass, LVESV, and LVEDV were indexed for height (m^2.7) to calculate left ventricular mass index (LVMI), left ventricular end-systolic volume index (LVESVI), and left ventricular end-diastolic volume index (LVEDVI), respectively. Serum total adiponectin and N-terminal proBNP (NT-proBNP) concentrations were measured at baseline, 3 months, and 12 months.

Methods:

We performed a prospective 1:1 observational study comparing KT candidates with ESKD either receiving a living donor organ (KT group) or waiting for a deceased donor organ (dialysis group).

Results:

Left ventricular mass index change was −1.98 ± 5.5 and −0.36 ± 5.7 g/m^2.7 for KT versus dialysis subjects (P = .44). Left ventricular mass change was associated with systolic blood pressure (SBP) (P = .0008) and average LV mass (P = .0001). Left ventricular ejection fraction did not improve (2.9 ± 6.6 vs 0.7 ± 4.9 %, P = .09), while LVESVI and LVEDVI decreased more post-KT than with continued dialysis (−3.36 ± 5.6 vs −0.22 ± 4.4 mL/m^2.7, P < .01 and −4.9 ± 8.5 vs −0.3 ± 9.2 mL/m^2.7, P = .02). Both adiponectin (−7.1 ± 11.3 vs −0.11 ± 7.9 µg/mL, P < .0001) and NT-proBNP (−3811 ± 8130 vs 1665 ± 20013 pg/mL, P < .0001) declined post-KT. Post-KT adiponectin correlated with NT-proBNP (P = .001), but not estimated glomerular filtration rate (eGFR) (P = .13). Change in adiponectin did not correlate with change in LVEF in the KT group (Spearman ρ = 0.16, P = .31) or dialysis group (Spearman ρ = 0.19, P = .21).

Limitations:

Few biomarkers of cardiac function were measured to fully contextualize their role during changing kidney function. Limited intrapatient biomarker sampling and CMR measurements precluded constructing dose-response curves of biomarkers to LV mass and function. The CMR timing in relation to dialysis was not standardized.

Conclusions:

The LVESVI and LVEDVI but not LVMI or LVEF improve post-KT. LVMI and LVEF change is independent of renal function and adiponectin. As adiponectin correlates with NT-proBNP post-KT, improved renal function through KT restores the normal heart-endocrine axis.

Early diastolic strain rate measurements by cardiac MRI in breast cancer patients treated with trastuzumab: a longitudinal study

We evaluated temporal changes in early diastolic strain rates by cardiovascular magnetic resonance (CMR) as an early detector of trastuzumab-induced ventricular dysfunction. We conducted a prospective, multi-centre, longitudinal observational study of 41 trastuzumab-treated breast cancer women who underwent serial CMR (baseline, 6, 12, and 18 months). Two blinded readers independently measured left ventricular ejection fraction (LVEF), peak systolic strain parameters (global longitudinal strain [GLS] and global circumferential strain [GCS]), and early diastolic strain rate parameters (global longitudinal diastolic strain rate [GLSR-E], global circumferential diastolic strain rate [GCSR-E], and global radial diastolic strain rate [GRSR-E]), by feature tracking (FT-CMR) using CMR42. There was a significant decline in peak systolic strain GLS and GCS at 6 months (p = 0.024 and p < 0.001, respectively) and 12 months (p = 0.002 and p < 0.001, respectively), followed by recovery at 18 months, which paralleled decline in LVEF at 6 months (p = 0.034) and 12 months (p = 0.012). Conversely, early diastolic strain rates GLSR-E and GCSR-E did not significantly change over 18 months (p > 0.10), while GRSR-E was marginally significant at 12 months (p = 0.021). There was no significant correlation between changes at 6 months in LVEF and GLSR-E or GRSR-E (p > 0.10), and a marginally significant weak correlation between LVEF and GCSR-E (p = 0.046). Among trastuzumab-treated patients without overt cardiotoxicity, there was no consistent temporal change in FT-CMR-derived diastolic strain rate parameters up to 18 months, in contrast to decline in systolic strain and LVEF. Systolic strains by FT-CMR are likely more useful than diastolic strain rates for monitoring subclinical trastuzumab-related myocardial dysfunction.ClinicalTrials.gov identifier NCT01022086.