Michael G. Fradley

Prognostic Utility of Novel Biomarkers of Cardiovascular Stress The Framingham Heart Study

Background— Biomarkers for predicting cardiovascular events in community-based populations have not consistently added information to standard risk factors. A limitation of many previously studied biomarkers is their lack of cardiovascular specificity. Methods and Results— To determine the prognostic value of 3 novel biomarkers induced by cardiovascular stress, we measured soluble ST2, growth differentiation factor-15, and high-sensitivity troponin I in 3428 participants (mean age, 59 years; 53% women) in the Framingham Heart Study. We performed multivariable-adjusted proportional hazards models to assess the individual and combined ability of the biomarkers to predict adverse outcomes. We also constructed a “multimarker” score composed of the 3 biomarkers in addition to B-type natriuretic peptide and high-sensitivity C-reactive protein. During a mean follow-up of 11.3 years, there were 488 deaths, 336 major cardiovascular events, 162 heart failure events, and 142 coronary events. In multivariable-adjusted models, the 3 new biomarkers were associated with each end point (P<0.001) except coronary events. Individuals with multimarker scores in the highest quartile had a 3-fold risk of death (adjusted hazard ratio, 3.2; 95% confidence interval, 2.2–4.7; P<0.001), 6-fold risk of heart failure (6.2; 95% confidence interval, 2.6–14.8; P<0.001), and 2-fold risk of cardiovascular events (1.9; 95% confidence interval, 1.3–2.7; P=0.001). Addition of the multimarker score to clinical variables led to significant increases in the c statistic (P=0.005 or lower) and net reclassification improvement (P=0.001 or lower). Conclusion— Multiple biomarkers of cardiovascular stress are detectable in ambulatory individuals and add prognostic value to standard risk factors for predicting death, overall cardiovascular events, and heart failure.

Distribution and Clinical Correlates of the Interleukin Receptor Family Member Soluble ST2 in the Framingham Heart Study

BACKGROUND Soluble ST2 (sST2) is a cardiac biomarker whose concentration rises in response to myocardial strain. Increased sST2 concentrations may predict adverse outcomes in patients with heart failure and myocardial infarction. Because sST2 was largely undetectable with first-generation assays in ambulatory individuals, there are few data regarding its distribution and correlates in community-based populations. METHODS We measured sST2 using a highly sensitive ELISA in 3450 Framingham Heart Study participants who attended a routine examination. We used multivariable linear regression models to identify covariates associated with sST2 in the general sample. We obtained a reference sample (n = 1136) by excluding individuals with prevalent coronary disease, heart failure, atrial fibrillation, diabetes, hypertension, obesity, valvular disease, left ventricular systolic dysfunction, and pulmonary and renal dysfunction. We used empiric and quantile regression techniques to estimate the 2.5th, 50th, 97.5th, and 99th quantiles. RESULTS In the general sample (mean age 59 years, 55% women), systolic blood pressure (P = 0.006), antihypertensive medication use (P = 0.03), and diabetes (P < 0.001) were associated with sST2 concentrations. In the reference sample (mean age 55, 59% women), male sex (P < 0.0001) and older age (P = 0.004) were predictive of higher sST2 concentrations. Quantile and empirical methods were used to define the reference intervals. Using the empirical approach, upper 99% percentile values in different age groups ranged from 46.6 to 64.4 μg/L in men and 36.7 to 53.0 μg/L in women. CONCLUSIONS In a well-characterized, community-based cohort, values for sST2 differ between men and women, increase with age, and are associated with diabetes and hypertension.

Relation between soluble ST2, growth differentiation factor-15, and high-sensitivity troponin I and incident atrial fibrillation

BACKGROUND We investigated whether circulating concentrations of soluble ST2, growth differentiation factor-15 (GDF-15), and high-sensitivity troponin I (hsTnI) are associated with incident atrial fibrillation (AF) and whether these biomarkers improve current risk prediction models including AF risk factors, B-type natriuretic peptide (BNP), and C-reactive protein (CRP). METHODS We studied the relation between soluble ST2, GDF-15, and hsTnI and development of AF in Framingham Heart Study participants without prevalent AF. We used Cox proportional hazard regression analysis to examine the relation of incident AF during a 10-year follow-up period with each biomarker. We adjusted for standard AF clinical risk factors, BNP, and CRP. RESULTS The mean age of the 3,217 participants was 59 ± 10 years, and 54% were women. During a 10-year follow-up, 242 participants developed AF. In age- and sex-adjusted models, GDF-15 and hsTnI were associated with risk of incident AF; however, after including the AF risk factors and BNP and CRP, only hsTnI was significantly associated with AF (hazard ratio per 1 SD of loge hsTnI, 1.12, 95% CI 1.00-1.26, P = .045). The c statistic of the base model including AF risk factors, BNP, and CRP was 0.803 (95% CI 0.777-0.830) and did not improve by adding individual or all 3 biomarkers. None of the discrimination and reclassification statistics were significant compared with the base model. CONCLUSION In a community-based cohort, circulating hsTnI concentrations were associated with incident AF. None of the novel biomarkers evaluated improved AF risk discrimination or reclassification beyond standard clinical AF risk factors and biomarkers.

Cardio-Oncology Training: A Proposal From the International Cardioncology Society and Canadian Cardiac Oncology Network for a New Multidisciplinary Specialty

There is an increasing awareness and clinical interest in cardiac safety during cancer therapy as well as in optimally addressing cardiac issues in cancer survivors. Although there is an emerging expertise in this area, known as cardio-oncology, there is a lack of organization in the essential components of contemporary training. This proposal, an international consensus statement organized by the International Cardioncology Society and the Canadian Cardiac Oncology Network, attempts to marshal the important ongoing efforts for training the next generation of cardio-oncologists. The necessary elements are outlined, including the expectations for exposure necessary to develop adequate training. There should also be a commitment to local, regional, and international education and research in cardio-oncology as a requirement for advancement in the field.

Cardiovascular Complications of Targeted Therapies for Chronic Myeloid Leukemia

Opinion statementThe development of tyrosine kinase inhibitors (TKIs) dramatically changed the treatment landscape for many different cancers including chronic myeloid leukemia (CML). With the introduction of imatinib, the first TKI developed and approved to effectively treat CML, patient survival has increased dramatically and, in some cases, this fatal cancer can be managed as a chronic disease. Since the approval of imatinib in 2002, four additional TKIs have been developed to treat this disease including the second-generation TKIs nilotinib, dasatinib, and bosutinib and the third-generation TKI ponatinib. Despite their significant impact on the progression of CML, there is increasing recognition of cardiovascular toxicities which can limit their long-term use and impact patient morbidity and mortality. The majority of the cardiotoxicities are associated with the second- and third-generation TKIs, the most concerning of which are vascular events including myocardial infarction, stroke and peripheral arterial disease. In addition, QT prolongation, pleural effusions, and both systemic and pulmonary hypertension are also observed. It is essential for both cardiologists and oncologists to possess knowledge of these issues in order to develop appropriate monitoring and risk mitigation strategies to prevent these toxicities and avoid premature cessation of the drug.

Anti-VEGF-Induced Hypertension: a Review of Pathophysiology and Treatment Options

Opinion statementAbnormal intracellular signaling has been implicated in the development of many different types of cancer. Therapies targeting these abnormal pathways have revolutionized the treatment of many malignancies leading to significantly improved outcomes and survival. Despite these advances, cardiovascular toxicity is a frequently reported complication. Angiogenesis is the physiologic process of new blood vessel development and can be dysregulated in some forms of cancer. VEGF inhibitors are the pharmaceutical agents targeting this pathway; however hypertension is a commonly observed toxicity which can have significant adverse consequences including premature cessation of therapy if adequate blood pressure control cannot be achieved. This review will provide a comprehensive discussion about hypertension due to VEGF inhibition, focusing on pathophysiology, frequently used agents, and available treatment options for VEGF-induced hypertension.

Arrhythmias and Other Electrophysiology Issues in Cancer Patients Receiving Chemotherapy or Radiation

Enhanced understanding of cancer biology has significantly increased treatment options and dramatically improved outcomes for patients with malignancies. Despite these advances, many therapies have cardiovascular toxicities which can affect morbidity and mortality independent of the oncologic prognosis. Arrhythmias and other electrophysiology issues are increasingly identified as common complications of cancer therapy. Atrial fibrillation and other supraventricular arrhythmias are frequently observed in cancer patients receiving chemotherapy, often due to their effects on intracellular signaling pathways. Similarly, many oncologic pharmaceuticals can lead to QT prolongation and possible ventricular arrhythmias including torsades do pointes. Management of these arrhythmias can be challenging as typical treatment strategies may not be feasible in cancer patients. Finally, a proportion of individuals with cancer will present with an implantable cardiac device (pacemaker or defibrillator) which poses unique challenges should radiation be necessary in the region of the device. Given the frequency of electrophysiology complications in cancer patients, it is essential for cardio-oncologists to possess knowledge of these issues in order to provide optimal care.

QT Prolongation and Oncology Drug Development

Many pharmaceutical agents interact with cardiac ion channels resulting in abnormal ventricular repolarization and prolongation of the QT interval. In rare circumstances, this has resulted in the development of the potentially life-threatening arrhythmia, torsades de pointes. It is recognized, however, that accurate measurement of the QT interval is challenging, and it is a poor predictor for the development of this arrhythmia. Nevertheless, QT interval monitoring is an essential part of pharmaceutical development, and significant increases in the QT interval may prevent a drug from gaining approval.

Bortezomib-Induced Complete Heart Block and Myocardial Scar: The Potential Role of Cardiac Biomarkers in Monitoring Cardiotoxicity.

Bortezomib is a proteasome inhibitor used to treat multiple myeloma and mantle cell lymphoma. Traditionally, bortezomib was thought to have little cardiovascular toxicity; however, there is increasing evidence that bortezomib can lead to cardiac complications including left ventricular dysfunction and atrioventricular block. We present the case of a 66-year-old man with multiple myeloma and persistent asymptomatic elevations of cardiac biomarkers who developed complete heart block and evidence of myocardial scar after his eighth cycle of bortezomib, requiring permanent pacemaker placement. In addition to discussing the cardiovascular complications of bortezomib therapy, we propose a potential role for biomarkers in the prediction and monitoring of bortezomib cardiotoxicity.

Rupture of the Posteromedial Papillary Muscle Leading to Partial Flail of the Anterior Mitral Leaflet

An 86-year-old woman with a history of hypertension presented with acute onset of chest pain and evidence of shock (hypotension and tachycardia). For the preceding 2 weeks, she had been experiencing intermittent nausea and vomiting; proton pump inhibitors did not improve her symptoms. The ECG showed ST elevations in the inferior leads and ST depressions in leads V1 and V2, with reciprocal ST depressions in leads I and aVL, suggesting an acute inferoposterior infarction (Figure 1). Physical examination also revealed a new 2/6 holosystolic murmur at the apex and significant bilateral rales. She was taken emergently to the cardiac catheterization laboratory, where 100% thrombotic occlusion of the middle right coronary artery was revealed (Figure 2A). A left ventriculogram revealed severe (4+) mitral regurgitation with a normal-sized left …