Abstract P1-03-07: Breast cancer diagnosis is associated with relative left ventricular hypertrophy
Authors: Kirkham A , Xu L , Wang H , Chow K , Pagano JJ , White J , Haykowsky MJ , Dyck JR , Ezekowitz JA , Oudit GY , Mackey JR , Thompson RB , Pituskin E , Paterson I 
Published: May 2019

Background: Cardiac dysfunction is a major concern for patients with breast cancer (BC) receiving adjuvant therapy. Retrospective, cross-sectional echocardiographic data suggests that patients with cancer have reduced myocardial strain prior to cancer therapy exposure. Cardiac magnetic resonance (CMR) is the gold standard imaging modality for cardiac structure and function and can also evaluate myocardial micro-architecture with T1 mapping. We hypothesized that treatment naïve patients with early-stage BC (ESBC) have abnormal myocardial tissue characteristics on CMR.

Methods: Women with newly diagnosed ESBC were prospectively recruited for CMR prior to cancer drug treatment. Those with hypertension, diabetes mellitus or prior cancer treatments were excluded. Age and sex matched healthy controls were identified from a prior prospective study. All participants underwent a non-contrast CMR scan on a 1.5T magnet. Image acquisition included cines for cardiac structure and function as well as T1 mapping using saturation recovery single-shot acquisitions. Global longitudinal strain (GLS) was derived from cine images. Demographics and imaging metrics for healthy controls and patients were compared using two-sample t-test.

Results: 106 patients with ESBC, mean age 51±9, were included along with 55 matched healthy controls. Body mass index and systolic blood pressure were similar between groups, however resting heart rate was elevated in patients compared to controls, 77±11 vs 67±11 /min respectively, p&lt;0.001 (Table 1). On CMR there was no difference in left ventricular volume or ejection fraction however global longitudinal strain was higher in patients compared to controls, -20.9±2.3 vs -19.9±3.7%, p=0.04 (Table 2). Left ventricular mass was higher compared to controls, 52±6 and 47±6 g/m2 respectively, p&lt;0.001. However myocardial T1 was similar between groups, T1=1198±27ms for controls vs 1206±46ms for patients, p=0.42.

Conclusions: The cardiac phenotype of patients with ESBC is characterized by relative left ventricular hypertrophy with normal myocardial tissue. Further understanding of the mechanisms involved may provide insight into the cardiovascular risk associated with BC diagnosis.

Table 1.Demographics Healthy Controls (n=55)Breast Cancer (n=106)P valueAge, years (SD)52(14)51(9)0.49Body mass index, kg/m2 (SD)26(5)27(6)0.38Hypertension, number00NADiabetes Mellitus, number00NAReceptor status, number (%)  NAER/PRNA92(87%) HER2NA74(70%) Triple negativeNA2(2%) Stage, number (%)  NA1NA43(42%) 2NA41(38%) 3NA23(20%) Systolic blood pressure, mmHg (SD)127(15)124(13)0.19Heart rate, /min (SD)67(11)77(11)&lt;0.001SD=standard deviation, NA=not applicable

Table 2.Cardiac Magnetic Resonance Healthy Controls (n=55)Breast Cancer (n=106)P valueLVEF, % (SD)62(4)62(5)0.91Indexed LVEDV, ml/m2 (SD)69(9)72(14)0.18Indexed LV mass, g/m2 (SD)47(6)52(6)&lt;0.001LV mass/LVEDV (SD)0.69(0.08)0.74(0.13)0.002Indexed left atrial volume, ml/m2 (SD)40(9)37(10)0.21Global longitudinal strain, % (SD)-19.9(3.7)-20.9(2.3)0.04Myocardial T1, ms (SD)1198(27)1206(46)0.42SD=standard deviation, LVEF=left ventricular ejection fraction, LVEDV=left ventricular end-diastolic volume, LV=left ventricular

Citation Format: Kirkham A, Xu L, Wang H, Chow K, Pagano JJ, White J, Haykowsky MJ, Dyck JR, Ezekowitz JA, Oudit GY, Mackey JR, Thompson RB, Pituskin E, Paterson I. Breast cancer diagnosis is associated with relative left ventricular hypertrophy [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P1-03-07.