Impact of Systemic Volume Status on Cardiac Magnetic Resonance T1 Mapping

Abstract

Diffuse myocardial fibrosis is a key pathophysiologic feature in heart failure and can be quantified by cardiac magnetic resonance (CMR) T1 mapping. However, increases in myocardial free water also prolong native T1 times and may impact fibrosis quantification. Thus far, the impact of systemic patient volume status remains unclear. In this study, native T1 time by CMR was investigated in hemodialysis (HD) patients (n = 37) and compared with healthy controls (n = 35). Volume status was quantified by bioimpedance spectroscopy and correlated with CMR T1 time. While no differences between HD patients and controls were present with regard to age (p = 0.180), height (p = 0.535), weight (p = 0.559) and left ventricular (LV) ejection fraction (p = 0.273), cardiac size was significantly larger in HD patients (LV end-diastolic volume 164 ± 53 vs. 132 ± 26 ml, p = 0.002). Fluid overloaded HD patients had significantly longer native T1 times than normovolemic HD patients and healthy controls (1,042 ± 46 vs. 1,005 ± 49 vs. 998 ± 47 ms, p = 0.030). By regression analysis, T1 time was significantly associated with fluid status (r = 0.530, p = 0.009, post-HD fluid status). Our data strongly indicate that native CMR T1 time is significantly influenced by systemic volume status. As fluid overload is common in patients with cardiovascular diseases, this finding is important and requires further study.

Consensus-based technical recommendations for clinical translation of renal T1 and T2 mapping MRI

“…The expert panel recommended that subjects should be scanned in a normal hydration status when clinically appropriate [R 1]. Little is known about the influence of hydration state on T1 or T2 values of the kidney; however, cardiac T1 mapping has shown that fluid overload significantly prolongs native T1 [39]. As fluid overload is also common in patients with renal disease, this can be an important confounder for the interpretation of native T1.…”

Cardiac Imaging in Dialysis Patients

“…Graham-Brown et al 56 concluded that native T1 mapping was a reproducible marker of myocardial fibrosis, independent of volume status, in HD patients in a small single-center cross-sectional study. Conversely, Antlanger et al 57 found that T1 mapping was significantly influenced by volume status, as determined using bioimpedence spectroscopy, when comparing hypovolemic with euvolemic HD patients. These studies highlight the critical need for further studies to determine the effectiveness of native T1 mapping to differentiate myocardial fibrosis and edema in ESKD.…”

Association between ratio for diameters of pulmonary artery to ascending aorta bifurcation in chest CT scan and number of involved vessels in coronary angiography

“…Antlanger et al [ 16 ] reported PA/Ao ratio as a prognostic marker that is related to the severity of disease, and is also associated with some risk factors such as diabetes, atrial fibrillation, right-sided heart failure, Brain natriuretic peptide (BNP), and low Glomerular filtration rate (GFR), especially in women. Nevertheless, in our study, gender was not related to the severity of involvement in the subjects.…”

“…Pulmonary hypertension is related to heart failure with ejection fraction preservation, morbidity, and mortality [ 6 , 7 ], especially in chronic obstructive pulmonary disease (COPD) patients [ 8 , 9 ]. An association has been oberved between pulmonary hypertension and pulmonary artery to ascending aorta diameter in these patients in previously performed studies [ 10 , 11 ], as a prognostic factor in cardiovascular diseases [ 12 , 16 ]. However, the diagnostic role is not considered yet.…”

“…It has shown an increasing trend in many countries including Iran with a raise percentage between 25 and 40 percent [4][5][6][7]. Also, there are multiple risk factors for coronary artery disease [8][9][10][11][12][13][14], which can even increase the severity of coronary artery disease [15][16][17][18][19][20]. Prompt diagnosis and treatment of disease can lead to decrease in mortality and mobidity [21].…”