A New Era for Cardio-Oncology

As the fight against cancer advances, so too does the understanding that safeguarding heart health is a crucial piece of the puzzle – ushering in the rise of cardio-oncology as an essential medical discipline.

The first cardio-oncology program was established in the United States 25 years ago, and in 2015 the American College of Cardiology (ACC) debuted a Cardio-Oncology Intensive Session at its annual conference. Today the ACC, the American Heart Association, and the European Society of Cardiology (ESC) have dedicated working groups focused on cardio-oncology, while the International Cardio-Oncology Society (IC-OS) boasts 1,100 members from more than 30 countries.

“Tremendous effort has been made in advancing the field of cardio-oncology, which has seen rapid growth here in the U.S. and abroad,” reports Diego Sadler, MD, Section Head of Cardio-Oncology at Cleveland Clinic in Florida. “We’ve learned a lot about how to prevent, detect and treat cancer treatment related cardiovascular disease, but there is still so much more we don’t know and even more that we need to do to improve patient outcomes worldwide.”

A bidirectional relationship

Dr. Sadler notes that cardio-oncology today is much more than just treating toxicities. “There is a commonality between cancer and cardiovascular disease, including common risk factors and a bidirectionality between these two worldwide leading causes of mortality,” he says.

According to the National Cancer Institute, the number of U.S. cancer survivors is projected to reach 26 million by 2040. Studies indicate that patients with cancer face a 2- to 6-times higher risk of cardiovascular disease mortality compared to the general population.

“Likewise, there is growing evidence that patients with cardiovascular disease, such as heart failure and coronary artery disease, have cancer more frequently than the general population,” explains Dr. Sadler. “We need to better understand this relationship.”

New leadership role

Dr. Sadler has been on the frontline of efforts to advance the young discipline at the intersection of cardiology and oncology/hematology. In addition to serving on the IC-OS’s Education & Training Advisory Committee since 2020, he was inducted in April as chair of the American College of Cardiology’s Cardio-Oncology Section Leadership Council, a position he’ll hold for the next three years.

"I’m excited to collaborate with such outstanding groups to expand access to cardio-oncology care, foster a dedicated platform for scientific advancement, advocacy, and education, and strengthen partnerships with state chapters while forging new global collaborations," Dr. Sadler says of his new role.

He believes the next five years will see major progress, including the ongoing efforts to establish cardio-oncology as a certified medical subspecialty with the American Board of Medical Specialties. “To reach this bar, we must show cardio-oncology serves a unique medical need, has a distinct body of scientific knowledge, and contributes to patient care in a way that existing specialties do not,” he says.

Establishing quality metrics

One of the initiatives essential to the future of cardio-oncology, notes Dr. Sadler, is defining and measuring quality metrics within the field to improve patient outcomes and reduce variations in clinical practice. He is part of an international team of specialists from the IC-OS and ACC Cardio-Oncology Section Leadership Council who joined forces to propose a roadmap for establishing quality metrics specific to cardio-oncology.

Published earlier this year in the JACC: CardioOncology, the document acts as a guide for future progress. It draws on both the Institute of Medicine (IOM) framework for evaluating healthcare quality and the Donabedian model. The IOM identifies six domains critical to health care quality: safety, timeliness, effectiveness, efficiency, equity, and patient-centeredness. While the Donabedian model designates quality metrics as either structural, process or outcome focused.

"The subspecialty of heart failure serves as a strong example of how performance and quality metrics can drive improvements in patient outcomes," says Dr. Sadler. "By systematically analyzing cardio-oncology quality metrics, we aim to refine clinical guidelines and ultimately enhance patient care."

Expanding clinical guidelines

Currently, three professional societies have issued guidelines supporting clinicians in managing cancer therapy-related cardiovascular toxicity (CTR-CVT). In 2016, the American Society of Clinical Oncology (ASCO) published the Clinical Practice Guideline on the Prevention and Monitoring of Cardiac Dysfunction in Survivors of Adult Cancers, which includes 25 individual recommendations.

This was followed by cardio-oncology guidelines from the European Society of Cardiology in 2022 that included 272 recommendations on risk prediction, management, and surveillance strategies for patients with cancer treated with potential cardiotoxic therapy. And this year the Heart Failure Society of America issued a scientific statement on heart failure care among patients with active cancer diagnoses and cancer survivors.

“Despite the progress being made, these guidelines are most often based on expert opinion and data from nonrandomized clinical trials,” states Dr. Sadler. “There is a tremendous need for further research to inform recommendations in cardiotoxicity risk assessment and management.”

Global registry pilot phase

Dr. Sadler points to the important role the Global Cardio-Oncology Registry (G-COR) will have in helping establish the incidence of CTR-CVT, identify risk factors, and lead to the development of validated risk score models to guide treatment decisions in different geographic locations throughout the world.

The G-COR is a multinational, multicenter prospective observational cohort registry launched in March 2023. The registry has enrolled 700 breast cancer patients across 19 U.S. academic and community hospitals during its pilot phase.

“Cleveland Clinic Weston Hospital was the lead enrollment site for the breast cancer pilot and enrolled 120 patients,” says Dr. Sadler. He serves as principal investigator of the G-COR and is based at Weston Hospital, which was recently recertified as a Gold Center of Excellence by the IC-OS (2025-2028). It is the only center in South Florida and one of just three in the state to achieve this distinction.

Last year, Dr. Sadler and a team of researchers reported on the demographic and exercise habits of an early cohort of 264 breast cancer patients enrolled in the registry during their initial cardio-oncology consultation. The team identified demographic differences that exist in the cohort by hospital type, race, ethnicity, as well as timing for consultation. Their findings were shared via poster presentation at the ACC’s 2024 Annual Scientific Session & Expo.

“Long-term follow up of registry participants will help us better understand demographic, clinical and socioeconomic variables that impact access and outcomes in cardio-oncology care,” explains Dr. Sadler. “Our goal is to improve care pathways that maximize overall survival and quality of life for our patients.”

Once fully activated, the G-COR will include 119 medical centers from 21 countries across five continents. These sites will enroll approximately 5,000 patients worldwide within three distinct patient populations: individuals with breast cancer, hematological malignancies, and those treated with check point inhibitors immunotherapy.

"The research supported by this registry has the potential to shape cardio-oncology treatment strategies that could benefit countless patients," observes Dr. Sadler.