Elevated resting heart rate is a marker of subclinical left ventricular dysfunction in hodgkin lymphoma survivors

BACKGROUND: Thoracic irradiation is one of the cornerstones of Hodgkin lymphoma (HL) treatment, which contributes to high rates of long-term survivorship, but begets a life-long increased risk of heart disease including heart failure. At the cardio-oncology (CO) clinic, persistent sinus tachycardia or elevated resting heart rate (RHR) is frequently observed in these patients. The aim of this study was to evaluate the relation between RHR and left ventricular (LV) dysfunction. METHODS: In 75 HL survivors visiting our CO-clinic echocardiographic evaluation of LV systolic and diastolic function including global longitudinal strain (GLS) was performed to assess subclinical LV dysfunction. RESULTS: Median age of HL diagnosis was 24 [25th-75th percentile: [19], [29]] years with a 17 [12], [25] year interval to CO-clinic visit and 31 patients (41%) were male. Average RHR was 78 ± 14 bpm and 40% of patients (N = 30) had an elevated RHR defined as ≥ 80 bpm. While there was no difference in LV ejection fraction (55.6 ± 4.3 vs. 54.8 ± 6.6; p = 0.543), patients with elevated RHR had abnormal GLS (-15.9% vs. −18.3%, p = 0.045) and higher prevalence of diastolic dysfunction (73.3% vs. 46.7%; p = 0.022). GLS, E/e’ ratio and presence of diastolic dysfunction were independently associated with RHR when correcting for age, sex and mantle field irradiation. A significant improvement was observed of the RHR-association model with solely extracardiac confounders when LV-function parameters were added to the model (F-statistic = 6.36, p = 0.003). CONCLUSIONS: This study indicates RHR as a possible marker for subclinical LV-dysfunction in HL survivors.