Detection of Early Myocardial Dysfunction by Imaging Biomarkers in Cancer Patients Undergoing Photon Beam vs. Proton Beam Radiotherapy: A Prospective Study

1. Background: We sought to determine acute and subacute changes in cardiac function after proton beam (PBT) and photon beam (PhT) radiotherapy (RT) using conventional and two-dimensional speckle tracking echocardiography (2D-STE) in patients with malignant breast and thoracic tumors. 2. Methods: Between March 2016 and March 2017, 70 patients with breast or thoracic cancer were prospectively enrolled and underwent transthoracic echocardiography with comprehensive strain analysis at pretreatment, mid-treatment, end of treatment, and 3 months after RT. 3. Results: PBT was used to treat 44 patients; PhT 26 patients. Mean ± SD age was 55 ± 12 years; most patients (93%) were women. The median (interquartile range) of the mean heart dose was lower in the PBT than the PhT group (47 [27-79] vs. 217 [120-596] cGy, respectively; p < 0.001). Ejection fraction did not change in either group. Only the PhT group had reduced systolic tissue Doppler velocities at 3 months. 2D-STE showed changes in endocardial and epicardial longitudinal, radial, and circumferential early diastolic strain rate (SRe) in patients undergoing PhT (global longitudinal SRe, pretreatment vs. end of treatment (p = 0.04); global circumferential SRe, pretreatment vs. at 3-month follow-up (p = 0.003); global radial SRe, pretreatment vs. at 3-month follow-up (p = 0.02) for endocardial values). Epicardial strain values decreased significantly only in patients treated with PhT. Patients in the PhT group had a significant decrease in epicardial global longitudinal systolic strain rate (GLSRs) (epicardial GLSRs, at baseline vs. at end of treatment [p = 0.009]) and in GCSRe and GRSRe (epicardial GCSRe, at baseline vs. at 3-month follow-up (p = 0.02); epicardial GRSRe, at baseline vs. at 3-month follow-up (p = 0.03)) during treatment and follow-up. No changes on 2D-STE were detected in the PBT group. 4. Conclusions: Patients who underwent PhT but not PBT had reduced tissue Doppler velocities and SRe values during follow-up, suggesting early myocardial relaxation abnormalities. PBT shows promise as a cardiac-sparing RT technology.

Outcomes of Transcatheter Aortic Valve Implantation in Nonagenarians and Octogenarians (Analysis from the National Inpatient Sample Database)

Risks among nonagenarian (age ≥90 years) and octogenarian (age 80 to 89 years) patients who underwent transcatheter aortic valve implantation (TAVI) compared with clinically similar septuagenarian (age 70 to 79 years) patients remain unclear. This study aimed to assess the outcomes of TAVI in nonagenarians and octogenarians compared with septuagenarians. We conducted a retrospective cohort study using the National Inpatient Sample database to identify patients aged ≥70 years hospitalized for TAVI from 2016 to 2020 and to compare outcomes in nonagenarians and octogenarians versus septuagenarians. The primary outcome was in-hospital mortality. Secondary outcomes included procedural complications, length of stay (LOS), and total costs. The trends in in-hospital outcomes were evaluated. Results were adjusted for demographic/clinical factors. The total cohort included 263,325 patients hospitalized for TAVI, of whom 11.9% were nonagenarians, 51.1% octogenarians, and 37.0% septuagenarians. After adjustment, nonagenarians and octogenarians had higher odds of in-hospital mortality (adjusted odds ratio 1.80, 95% confidence interval 1.34 to 2.41 for nonagenarians; adjusted odds ratio 1.65, 95% confidence interval 1.35 to 2.01 for octogenarians), heart block, permanent pacemaker insertion, stroke, major bleeding, blood transfusion, and palliative care consultation than septuagenarians (all p <0.01). LOS was longer and the total costs were higher for nonagenarians and octogenarians (both p <0.01). Over the study period, in-hospital mortality decreased in nonagenarians (ptrend = 0.04), and major bleeding, permanent pacemaker insertion, LOS, and costs decreased in all patients aged ≥70 years (ptrend <0.01). In conclusion, nonagenarians and octogenarians who underwent TAVI have higher rates of mortality and procedure-related complications than clinically similar septuagenarians. Further research is necessary to optimize outcomes in this frail population.

Cardiac Masses Discovered by Echocardiogram; What to Do Next?

Cardiac tumors are rare conditions, typically diagnosed on autopsy, but with the advancement of imaging techniques they are now encountered more frequently in clinical practice. Echocardiography is often the initial method of investigation for cardiac masses and provides a quick and valuable springboard for their characterization. While some cardiac masses can be readily identified by echocardiography alone, several require incorporation of multiple data points to reach diagnostic certainty. Herein, we will provide an overview of the main clinical, diagnostic, and therapeutic characteristics of cardiac masses within the framework of their location.

Sodium-Glucose Cotransporter-2 Inhibitors in Heart Failure With Mildly Reduced or Preserved Ejection Fraction: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

BACKGROUND

Sodium-glucose cotransporter-2 inhibitors (SGLT2i) reduce the risk of heart failure (HF) hospitalizations and cardiovascular mortality among patients with HF and left ventricular ejection fraction (LVEF) ≤40%. There is emerging evidence of the benefits of SGLT2i in HF patients with a higher LVEF (>40%). We aimed to evaluate the benefits of SGLT2i in different subgroups of patients with HF and LVEF >40%.

METHODS

We searched PubMed, EMBASE, clinicaltrials.gov, Cochrane, and Google Scholar for randomized controlled trials (RCTs) comparing outcomes of SGLT2i vs placebo in patients with HF and LVEF >40%. The hazard ratios (HRs) and 95% confidence intervals (CIs) in each study were used for the meta-analysis. The primary composite outcome (PCO) was HF hospitalization or cardiovascular mortality. Secondary outcomes included HF hospitalization, cardiovascular mortality, and all-cause mortality.

RESULTS

Six RCTs with 15,989 patients were included (median follow-up = 27.3 months, 40.8% females). In patients with HF and LVEF >40%, SGLT2i were associated with significantly lower PCO compared to placebo (HR 0.80; 95% CI 0.74-0.86; P < 0.001). This was consistent across 10 of 13 subgroups examined, including LVEF. SGLT2i also reduced HF hospitalization but not cardiovascular or all-cause mortality. Patients <65 years old, from racial minorities, or from Asia receiving SGLT2i did not demonstrate a significant reduction in PCO.

CONCLUSIONS

SGLT2i significantly reduce the combined risk of HF hospitalization or cardiovascular mortality among patients with HF and LVEF >40%. However, younger patients, racial minorities, and patients from Asia did not demonstrate such a reduction. Further research is necessary to identify the reasons for such disparities.

Cardiotoxicities of Novel Therapies in Hematological Malignancies: Monoclonal Antibodies and Enzyme Inhibitors

Monoclonal antibodies (mAB) selectively target leukemia surface antigens and work by either blocking cell surface receptors or triggering the target cell's destruction. Similarly, enzyme inhibitors bind to complex molecular platforms and induce downstream mechanisms that trigger cell death. These are used in a variety of hematologic malignancies. Yet, they also elicit severe immune-mediated reactions as biological agents that require careful monitoring. Cardiovascular effects include cardiomyopathy, ventricular dysfunction, cardiac arrest, and acute coronary syndrome. While there have been scattered reviews of mAB and enzyme inhibitors, a consolidated resource regarding their cardiovascular risk profile is lacking. We provide general recommendations for initial screening and serial monitoring based on the literature.

Racial and Ethnic Disparities in the Use and Outcomes of Transcatheter Mitral Valve Replacement: Analysis From the National Inpatient Sample Database

Background Racial and ethnic disparities in outcomes exist following many cardiac procedures. Transcatheter mitral valve replacement (TMVR) has grown as an alternative to mitral valve surgery for patients at high surgical risk. The outcomes of TMVR by race and ethnicity are unknown. We aimed to evaluate racial and ethnic disparities in the outcomes of TMVR. Methods and Results We analyzed the National Inpatient Sample database from 2016 to 2020 to identify hospitalizations for TMVR. Racial and ethnic disparities in TMVR outcomes were determined using logistic regression models. Between 2016 and 2020, 5005 hospitalizations for TMVR were identified, composed of 3840 (76.7%) White race, 505 (10.1%) Black race, 315 (6.3%) Hispanic ethnicity, and 345 (6.9%) from other races (Asian, Pacific Islander, American Indian or Alaska Native, Other). Compared with other racial and ethnic groups, Black patients were significantly younger and more likely to be women (both P<0.01). There were no significant differences between White, Black, and Hispanic patients in in-hospital mortality (5.2% versus 5.0% versus <3.5%; P=0.89) and procedural complications, including heart block (P=0.91), permanent pacemaker (P=0.49), prosthetic valve dysfunction (P=0.45), stroke (P=0.37), acute kidney injury (P=0.32), major bleeding (P=0.23), and blood transfusion (P=0.92), even after adjustment for baseline characteristics. Adjusted vascular complications were higher in Black compared with White patients (P=0.03). Trend analysis revealed a significant increase in TMVR in all racial and ethnic groups from 2016 to 2020 (P_trend<0.05). Conclusions Between 2016 and 2020, Black and Hispanic patients undergoing TMVR had similar in-hospital outcomes compared with White patients, except for higher vascular complications in Black patients. Further comparative studies of TMVR in clinically similar White patients and other racial and ethnic groups are warranted to confirm our findings.

Cardiotoxicities of Novel Therapies in Hematologic Malignancies: Chimeric Antigen Receptor T-Cell Therapy and Bispecific T-Cell Engager Therapy

The field of malignant hematology is transforming with novel immunotherapeutic approaches. Unfortunately, quality of life, treatment efficacy, and life expectancy are negatively affected by cardiotoxic side effects of treatment. To date, the exact mechanism and incidence of cardiotoxicity associated with these therapies is unclear. These events are believed to be triggered or occur concurrently with cytokine release syndrome. Furthermore, there are no formal guidelines to provide evaluation, treatment, and surveillance. We aim to synthesize available literature with updates on the cardiotoxic effects of novel therapies used in malignant hematologic disorders, with a focus on chimeric antigen receptor T-cell therapy and bispecific T-cell engager therapy, along with a proposed algorithm that may guide pretreatment evaluation, monitoring during treatment, and post-treatment surveillance.

Treatment of Highly Angulated Lesions Using SuperCross Microcatheter

Unusually angulated coronary anatomy can decrease the success rate of coronary interventions by hindering successful wiring and equipment delivery. Additionally, due to the technical challenges involved, there is increased risk for complications such as perforations, dissections, stent loss, and equipment entrapment. In this case series, we illustrate the advantages of using angulated microcatheters to facilitate successful treatment of such patients in various clinical scenarios.

Mavacamten Treatment for Hypertrophic Cardiomyopathy: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

BACKGROUND

Hypertrophic cardiomyopathy (HCM) is the most common heritable cardiomyopathy, yet pharmacological therapy has been unchanged for decades until the recent introduction of mavacamten, a first-in-class cardiac myosin inhibitor. We assessed the efficacy and safety of mavacamten in HCM.

METHODS

To date, only 3 randomized controlled trials (RCTs) compared the outcomes of mavacamten versus placebo for HCM. We used a fixed effects model to calculate risk ratios (RRs) with 95% confidence intervals (CIs). The primary composite endpoint (PCE) was defined as either ≥1.5 mL/kg/min increase in peak oxygen consumption (pVO2) with ≥1 New York Heart Association functional class (NYHA-FC) improvement or ≥3.0 mL/kg/min increase in pVO2 without worsening of NYHA-FC. Secondary outcomes included ≥1 NYHA-FC improvement, septal reduction therapy (SRT) or guideline eligible for SRT, ≥1 serious adverse event (SAE), ≥1 treatment emergency adverse event (TEAE), atrial fibrillation (AF), and nonsustained ventricular tachycardia (NSVT).

RESULTS

Three RCTs (n=422, mean follow-up 24 weeks) were included. Compared to placebo, mavacamten achieved higher rates of PCE (RR 1.92; 95% CI 1.28-2.88; p=0.002) and ≥1 NYHA-FC improvement (RR 2.10; 95% CI 1.66-2.67; p<0.00001) and lower rates of SRT or guideline eligible for SRT (RR 0.29; 95% CI 0.22-0.39; p<0.00001). There were no differences between both groups in ≥1 SAE, AF, and NSVT, however mavacamten had higher rates of ≥1 TEAE.

CONCLUSIONS

In patients with HCM, mavacamten helps improve pVO2 and NYHA-FC and reduces SRT but may be associated with TEAE. Further research is warranted to evaluate the efficacy, safety, and long-term outcomes of mavacamten.

Impact of digoxin utilization on clinical outcomes following left ventricular assist device implantation

INTRODUCTION

We aimed to assess the impact of digoxin use following left ventricular assist device (LVAD) implantation on clinical outcomes.

METHODS

Patients implanted with continuous flow LVADs at a single academic medical center and survived to initial hospital discharge were included in the analysis (n = 346). Clinical events were captured at a maximum of 2 years of follow up. Digoxin use was defined as 30-day continuous use post-LVAD. Negative binomial regression and Kaplan-Meier method were used to assess the association between digoxin use and clinical outcomes.

RESULTS

Mean age of the cohort was 56 years (±13) and 23% (79/346) were female sex. Digoxin was used in 144 patients (41.6%) for a median of 268 days (IQR 154, 616). Digoxin use was associated with a significant reduction in cumulative incidence of gastrointestinal bleeding (GIB) (15% vs 26%, p = 0.004). After adjusting for age, hypertension, post-operative hemoglobin, RDW, potassium, and GFR, and use of angiotensin receptor/neprilysin inhibitor, there remained a significant 47% reduction in GIB incidence in patients treated with digoxin. There was no significant difference in cumulative incidence in right ventricular failure (RVF) between the two groups. There was no difference in overall 2-year survival between groups.

CONCLUSIONS

Digoxin use was associated with reduction in GIB events, but not in RVF or mortality. Further studies are needed to confirm these findings and to investigate optimal timing and patient population.

Prognostic Value of Myocardial Extracellular Volume Fraction and T2-mapping in Heart Transplant Patients

OBJECTIVES

The purpose of this study was to examine prognostic value of T1- and T2-mapping techniques in heart transplant patients.

BACKGROUND

Myocardial characterization using T2 mapping (evaluation of edema/inflammation) and pre- and post-gadolinium contrast T1 mapping (calculation of extracellular volume fraction [ECV] for assessment of interstitial expansion/fibrosis) are emerging modalities that have been investigated in various cardiomyopathies.

METHODS

A total of 99 heart transplant patients underwent the magnetic resonance imaging (MRI) scans including T1- (n = 90) and T2-mapping (n = 79) techniques. Relevant clinical characteristics, MRI parameters including late gadolinium enhancement (LGE), and invasive hemodynamics were collected. Median clinical follow-up duration after the baseline scan was 2.4 to 3.5 years. Clinical outcomes include cardiac events (cardiac death, myocardial infarction, coronary revascularization, and heart failure hospitalization), noncardiac death and noncardiac hospitalization.

RESULTS

Overall, the global native T1, postcontrast T1, ECV, and T2 were 1,030 ± 56 ms, 458 ± 84 ms, 27 ± 4% and 50 ± 4 ms, respectively. Top-tercile-range ECV (ECV >29%) independently predicted adverse clinical outcomes compared with bottom-tercile-range ECV (ECV <25%) (hazard ratio [HR]: 2.87; 95% confidence interval [CI]: 1.07 to 7.68; p = 0.04) in a multivariable model with left ventricular end-systolic volume and LGE. Higher T2 (T2 ≥50.2 ms) independently predicted adverse clinical outcomes (HR: 3.01; 95% CI: 1.39 to 6.54; p = 0.005) after adjustment for left ventricular ejection fraction, left ventricular end-systolic volume, and LGE. Additionally, higher T2 (T2 ≥50.2 ms) also independently predicted cardiac events (HR: 4.92; CI: 1.60 to 15.14; p = 0.005) in a multivariable model with left ventricular ejection fraction.

CONCLUSIONS

MRI-derived myocardial ECV and T2 mapping in heart transplant patients were independently associated with cardiac and noncardiac outcomes. Our findings highlight the need for larger prospective studies.

Different models for evaluation of growth traits and Kleiber ratio in an experimental flock of Iranian fat-tailed Afshari sheep

Records for Afshari sheep were retrieved from data collected between 2000 and 2005 at the Zanjan University experimental flock, at Zanjan, Iran. (Co)variance components and corresponding genetic parameters for birth weight (BW), weaning weight (WW), 6-month weight (W6), average daily gain from birth to weaning (ADGa), from birth to 6 months (ADGb), from weaning to 6 months (ADGc), Kleiber ratio at weaning (WWKR) and Kleiber ratio at 6 months of age (W6KR) were estimated using univariate and bivariate analyses by the DFREML procedure. The Kleiber ratio, defined as growth rate/metabolic weight, has been suggested to be a useful indicator of growth efficiency and an indirect selection criterion for feed conversion. Estimates of direct heritability (h(2)) were 0.23, 0.27, 0.11, 0.22, 0.07, 0.01, 0.13 and 0.06 for BW, WW, W6, ADGa, ADGb, ADGc, WWKR and W6KR, respectively. Maternal genetic effects represented a relatively large proportion of the total phenotypic variance for BW (m(2) = 0.22), whereas maternal permanent environmental effects were significant for W6 (c(2) = 0.15), ADGb (c(2) = 0.16), ADGc (c(2) = 0.14) and W6KR (c(2) = 0.16). Results of bivariate analyses indicated the variable genetic correlations between traits. The largest positive genetic relationships were between adjacent measurements. The moderate estimates of h(2) for early growth traits indicate that in Afshari sheep faster genetic improvement through selection is possible for these traits. In order to increase the efficiency of feed conversion, use of Kleiber ratio in selection programmes was recommended.

Kinetics studies on the lignan class of natural compounds that inhibits alpha-chymotrypsin

The mechanism of inhibition of the alpha-chymotrypsin enzyme by two lignans of the fused bistetrahydrofuran series, epiexcelsin (1) and 5'-demethoxyepiexcelsin (2), which were isolated from the Commiphora mukul Engl., was investigated. Lineweaver-Burk and Dixon plots and their secondary replots showed that these compounds were noncompetitive inhibitors of the enzyme. K(i) values for 1 and 2 were found to be 22.29 +/- 0.015 and 336.30 +/- 0.053 microM, respectively.

An investigation of the kinetic and anti-angiogenic properties of plant glycoside inhibitors of thymidine phosphorylase

We investigated the potential of symplocomoside (1) and symponoside (2), glycosides isolated from the bark of Symplocos racemosa to inhibit thymidine phosphorylase (TP) activity and associated angiogenesis. Compound 1 was a reversible, noncompetitive inhibitor of deoxythymidine binding to TP (IC(50) = 65.45 +/- 5.08 microM; K(i) = 62.83 +/- 2.10 microM) and 2 was a reversible, uncompetitive inhibitor (IC(50) = 94.17 +/- 4.05 microM; K(i) = 101.95 +/- 1.65 microM). Molecular modeling analysis indicated that both compounds bound at the active site of the enzyme but not solely to amino acid residues involved in catalysis. Both compounds were active in in vitro angiogenic assays inhibiting endothelial cell migration and invasion in Matrigel, but did not inhibit growth factor-induced proliferation and were not cytotoxic. Compound 1 may have potential as an anti-angiogenic and anti-tumor agent.

New salirepin derivatives from Symplocos racemosa

The phytochemical investigation of the n-butanol soluble fraction of the bark of stem of Symplocos racemosa Roxb. yielded two new phenolic glycosides of salirepin series, symplocuronic acid (1) and sympocemoside (2), while salirepin (3) was isolated for the first time from this plant. The structures of the new compounds were identified by 1D and 2D NMR techniques along with other spectral evidences and by comparison with the published data of closely related compounds.