T1 Mapping in HIV Patients With High and Low CD4+ Cell Counts
HIV-infection is associated with an increased risk for cardiovascular disease. Especially patients with low CD4+ counts have a higher incidence of structural heart disease. Myocardial T1 relaxation time, as well as T1-derived extracellular volume fraction are relatively new methods for non-invasive myocardial tissue characterization, including diffuse myocardial fibrosis.
In our study HIV-patients with high and low CD4+ counts are examined on a 3T MRI scanner (Ingenia 3T, Philips Medical, Best, Netherlands). Scanning protocol includes common SSFP sequences, STIR imaging and LGE [Late gadolinium enhancement]. All HIV patients are treated in the HIV outpatient clinic of the hospital's Internal Medicine department and have an unremarkable history of cardiac disease. Patients are recruited from all over Germany. In order to obtain reference values, a subgroup of healthy, age-matched controls is included in this study.
Aim of this study is to show differences in T1- and ECV-values in the investigated subgroups. In addition, we also want to create cut-off values for healthy and affected myocardium in asymptomatic HIV-infected patients. This study could show whether myocardial T1 mapping is a potential screening parameter for beginning heart disease as part of an HIV-infection, and whether an application in routine diagnostic is reasonable.
|Study Design:||Observational Model: Case Control
Time Perspective: Prospective
|Official Title:||Myocardial T1-mapping and T1-derived Extracellular Volume Fraction (ECV) in HIV-infection Patients With Chronic High and Low CD4+ Counts and in a Healthy Control Group|
- Native T1 Relaxation Times [ Time Frame: Measurement will be performed within 2 weeks after MRI scan ] [ Designated as safety issue: No ]T1 relaxation times will be directly obtained form the T1 maps through ROI analysis. T1 maps will be analyzed using a segmental approach. T1 relaxation times are given in [ms].
- Extracellular volume fraction (ECV) [ Time Frame: Measurement will be performed within 2 weeks after MRI scan ] [ Designated as safety issue: No ]
Hematocrit corrected ECV will be calculated using pre- and post-contrast T1 values for myocardium and blood pool using following formula:
ECV= (1⁄T1 "myocardium post contrast"-1⁄T1 "myocadium pre contrast")/(1⁄T1 "blood post contrast"-1⁄ T1 "blood pre contrast") x (1-hematocrit).
ECV is given in percentage.
- Cardiac function and aortic distensibility [ Time Frame: Measurement will be performed within 2 weeks after MRI scan ] [ Designated as safety issue: No ]
Cardiac function (left ventricular endsystolic volume (LV-ESV), left ventricular enddiastolic volume (LV-EDV), and left ventricular ejection fraction (LV-EF)) will be determined offline using a dedicated software (ViewForum, Philips Healthcare, Best, The Netherlands). LV-ESV and LV-EDV will be quantified manually by tracing the endocardial borders. LV-EF is given in percentage. LV-ESV and LV-EDV are given in [ml].
Aortic Distensibility will be calculated as:
Distensibility(10^-3 mmHg^-1 )=(Amax−Amin)/Amin x (Sys−Dias),where Amax and Amin represent the maximal and minimal cross-sectional area of the aorta on cine CMR images, and Sys and Dias represent the systolic and diastolic blood pressures (in millimetres of mercury), respectively.
|Study Start Date:||July 2013|
|Estimated Study Completion Date:||December 2014|
|Estimated Primary Completion Date:||December 2014 (Final data collection date for primary outcome measure)|
HIV patients with high CD4+ cell counts
HIV Infection, Chronic high CD4+ cell counts (>500 /μl), No known cardiac disease
HIV patients with low CD4+ cell counts
HIV Infection, Chronic low CD4+ cell counts (<200 /μl), No known cardiac disease
No known cardiac disease.
|Contact: Julian A Luetkens, MDemail@example.com|
|Contact: Claas P Naehle, MDfirstname.lastname@example.org|
|University of Bonn, Dept. of Radiology||Recruiting|
|Bonn, NRW, Germany, 53127|
|Contact: Claas P Naehle, MD email@example.com|
|Contact: Julian A Luetkens, MD firstname.lastname@example.org|
|Principal Investigator: Claas P Naehle, MD|
|Principal Investigator:||Claas P Naehle, MD||University of Bonn, Dept. of Radiology, Sigmund-Freud-Str. 25, 53127 Bonn, Germany|