Evaluation of Routine Use of Global Longitudinal Strain for the Early Detection of Subclinical Left Ventricular Dysfunction in Cancer Patients

Background:
Cardiac toxicity from cancer therapy has become a leading cause of morbidity and mortality in survivors, reaching mortality rate as high as 60% in two years. The most commonly used definition is a reduction in left ventricular ejection fraction (LVEF). According to the recent American and European Society of Echocardiography Expert Consensus, global longitudinal strain (GLS) is the optimal parameter for early detection of subclinical LV dysfunction.

Objectives:
To evaluate the frequency of global longitudinal strain (GLS) reduction in cancer patients and its correlation to LVEF reduction and other echocardiography parameters.

Methods:
A retrospective, single-center observational study that included 67 consecutive patients evaluated in the Cardio-oncology clinic from February to September 2016. All patients performed at least two echocardiography exams, including GLS. All exams were performed with the same vendor, technician and interpreting cardiologist. We evaluated the frequency of GLS reduction (once by ≥8% and then by >15% relative reduction), its correlation to LVEF reduction and if there are other predicting echocardiographic parameters.

Results:
Among 67 consecutive patients, 15 patients (22%) had >15% relative reduction in GLS, of which 67% had no concomitant EF reduction. Similarly, 27 patients (40%) had ≥8% relative reduction in GLS, of which 67% had no EF reduction. No other echocardiography parameters (including diastolic parameters, right ventricular function or systolic pulmonary artery pressure) were significant predictors for GLS reduction.

Conclusions:
Early identification of cardiac dysfunction is essential for the prevention of symptomatic heart failure. Our study demonstrates that GLS reduction is frequent among cancer patients and precedes the LVEF reduction and cannot be anticipated by other echocardiography parameters. Using GLS routinely during cancer treatment may lead to an early cardio protective treatment and prevention of irreversible LVEF reduction and heart failure.