Uptake of echocardiography amongst different risk groups for patients treated with cardiotoxic chemotherapy

Funding Acknowledgements

Type of funding sources: None.

Background

Cardiovascular complications of cancer therapy are increasingly becoming a significant medical issue. Hence, the role of cardiovascular imaging in the assessment of baseline cardiovascular risk is becoming increasingly important. Current guidelines recommend a baseline transthoracic echocardiogram (TTE) prior to commencement of cardiotoxic chemotherapy (CC) but the uptake is presently inconsistent.

Purpose

Our study aimed to determine the uptake of a baseline TTE in a cohort of patients with solid organ malignancies (SOM) prior to commencing their treatment and to examine the patterns of uptake based on the risk of development of cardiotoxicity.

Methods

Patients with a SOM admitted to our institution between 2014-18 were examined. Demographic data, clinical comorbidities, cancer type, and chemotherapeutic regimens used were obtained from the patient’s electronic medical record. Included patients were divided into those receiving one of the 8 CC classes identified in the Cardio-Oncology Study Group and International Cardio-Oncology Society (COSG/ICOS) 2020 position statement1, and those who did not (control group). Those receiving CC were further stratified into risk groups according to the proformas proposed by the COSG/ICOS, while patients receiving immunotherapy for whom a proforma was not available, were considered a separate group. The uptake patterns of TTE in each group determined.

Results

Of 800 patients reviewed, 712 patients were included, and categorised into groups as shown in figure 1. Patients treated with CC had low uptake of a baseline TTE, and there was no difference compared to controls (14.4% vs 13.9%, p = 0.9). They were however more likely to have received a TTE during the course of treatment (32.3% vs 23.2%, p = 0.009). Figure 2 shows the rates of baseline TTE stratified by risk group. Compared to patients not on CC, only very high risk patients had a higher rate of baseline TTE (p < 0.001), while low risk patients had lower rates (p = 0.005). Compared to those not on CC, there was no difference in the rate of baseline TTE amongst immunotherapy patients, medium risk and high risk patients.

Conclusion

The uptake of baseline TTE in accordance with guidelines amongst patients receiving CC was very low. Based on the risk stratification proformas proposed by the COSG/ICOS, only very high risk patients were having a baseline TTE more frequently than those not treated with CC. The risk of future cardiotoxicity amongst low, medium and high risk patients, and those receiving immunotherapy, appears to be underappreciated, as these patients were not screened by TTE prior to commencing therapy. Increasing awareness of the agents that cause cardiotoxicity, and the establishment of formal protocols for these patients, may increase compliance with recommendations for TTE prior to commencing CC. Abstract Figure. Distribution of patients by risk group  Abstract Figure. Percentage of patients with baseline TTE

Left atrial reservoir strain is reduced in patients with myocardial infarction with non-obstructive coronary arteries

Background

Myocardial infarction with non-obstructive coronary arteries (MINOCA) represents a management conundrum given the poorly understood pathogenic mechanisms. In recent years, novel echocardiographic measures such as deformation/strain analysis have enabled early identification of left atrial (LA) remodelling and dysfunction which take place prior to structural alterations. LA dysfunction is an important biomarker of cardiovascular disease and an independent predictor of atrial arrhythmias which may play a fundamental role in the pathogenesis of MINOCA.

Purpose

The goal of our study was to evaluate and characterise LA function by speckle tracking strain echocardiography in patients with MINOCA.

Methods

Patients admitted to our institution with acute myocardial infarction were assessed and those diagnosed with MINOCA who underwent transthoracic echocardiogram (TTE) within 48-hours of their coronary angiogram were included. Diagnosis of MINOCA was based on the 2017 ESC working group position paper on myocardial infarction with non-obstructive coronary arteries. Two-dimensional speckle tracking strain analysis of the LA and left ventricle (LV) was performed offline using vendor independent software (TomTec Arena). Clinical and echocardiographic measures were compared to healthy controls identified from our echocardiography database. We excluded patients with history of atrial fibrillation, heart failure and LV dysfunction (LVEF <50%).

Results

The cohort consisted of 82 patients; 41 patients with MINOCA were compared to 41 age and sex matched controls (61% male, mean age 51±12.8 years). At baseline, patients with MINOCA had a higher prevalence of modifiable vascular risk factors including smoking, hypertension and diabetes (p<0.001 for all). Of the echocardiographic parameters, no differences in left ventricular (LV) parameters including LV global longitudinal strain (p=0.463), indexed LV mass (p=0.084) and the E/e' (p=0.391) was appreciated. Though there was no difference in LA volumes or volumetric parameters of LA function (LAEF; p=0.328), patients with MINOCA had a lower LA reservoir strain (29.7±8.5% vs 33.2±6.5%; p=0.04; 95% CI 0.32–5.33).

Conclusion

Patients with MINOCA demonstrated lower LASr despite normal LV and LA volumes. This suggests that LA dysfunction may play a role in the pathogenesis of MINOCA. Further studies are required to evaluate the significance of our findings.

Funding Acknowledgement

Type of funding sources: None.