Baseline cardiovascular ECG assessment prior to systemic anti-cancer treatment across breast, lung and gastrointestinal malignancies: a guidelines adherence audit in the real world

Background Cardiotoxicity is a recognised complication of many systemic anti-cancer therapies (SACT). European Society of Cardiology’s Cardio-Oncology 2022 Guidelines recommend cardiovascular risk assessments for all patients starting potentially cardiotoxic SACT, or those with pre-existing cardiovascular risk factors (CVRF). A baseline ECG quickly detects arrhythmias, conduction abnormalities and QT prolongation, making it a key part of initial assessment. Purpose This audit evaluated the proportion of cancer patients in a district general hospital who had a baseline ECG performed within one month of SACT initiation. Secondary objectives were prevalence of pre-existing CVRF and completion of an ECG or involvement of cardio-oncology services after starting SACT. Methods Data were collected for 155 cancer patients who commenced their first cycle of SACT between April 2023 and April 2024. Patients received standard chemotherapy, immunotherapy, hormonal therapy and targeted agents. We evaluated: (1) completion of a baseline ECG within one month before starting SACT; (2) completion of an ECG at any point after starting SACT; (3) presence of pre-existing CVRF including hypertension, arrhythmias, heart failure and ischaemic heart disease and; (4) referral to cardio-oncology services for potential cancer therapy-related cardiac dysfunction (CTRCD). Results The mean age of the 155 cancer patients was 62 ± 13 years, (100 female: 55 male, 64.5%: 35.5%). Cancer types were breast cancer (41.2%), lung cancer (18%), gastro-intestinal cancers (40.6%). Treatment included chemotherapy (86%, with 39% of all patients receiving chemotherapy alone), immunotherapy (19%), targeted drug therapy (34%) and hormonal treatment (32%). Only 35 patients (23%) had a baseline ECG within one month of starting SACT. Of the remaining 120 patients without a documented ECG, 34 (29%) had at least one pre-existing CVRF. Seven patients in total (4.5%) were referred to the cardio-oncology service for suspected CTRCD, four of whom had pre-existing CVRFs. Overall, 96 patients (62%) had an ECG performed at some point after starting SACT, but timing varied widely, with a mean delay of 113 ± 129 days. Review of pre-SACT checklists and chemotherapy documentation revealed that although routine baseline investigations included blood tests and observations, there was no designated prompt for a baseline ECG, highlighting a potential gap in the standard of care. Conclusion Our real-world audit data across three common cancer types demonstrates a clear gap between guideline recommendations and current practice, particularly for patients with pre-existing CVRFs. The absence of a structured prompt for ECGs within pre-SACT documentation likely contributes to low uptake. Incorporating a mandatory ECG prompt into pre-treatment checklists and updating local protocols represents a simple, high-impact intervention to improve early detection of potential cardiotoxicity.