Evaluation of the prognostic significance of myocardial perfusion defects, wall motion abnormalities and late gadolinium enhancement in MRI of asymptomatic diabetics and healthy subjects

• Applicant: Dr. Nikolaos Panagiotopoulos
• Subject Area: Nuclear Medicine, Radiotherapy, Radiobiology
• Term: from 2016 to 2021
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 314797964

According to the WHO the global prevalence of diabetes mellitus is set to increase from 30 million in 1985 to at least 300 million by 2025. Diabetics bear a multifold risk-increase for major adverse cardiac events (MACE). Early risk stratification is necessary to initiate preventive measures. The aim of the proposed research is to validate the prognostic value of cardiovascular magnetic resonance (CMR) concerning MACE in asymptomatic diabetics and non-diabetics. Although related studies have already been conducted, they were all compromised by a selection bias that resulted in cohorts containing mainly symptomatic subjects. From a medical perspective it is the asymptomatic population that promises to benefit the most from an earlier detection and treatment at a still subclinical stage. The main motivation for this work is therefore the potential benefit for patient care that could result from a better understanding and interpretation of pathological CMR findings.To achieve this, we are going to analyse already acquired data of a longitudinal and cross-sectional CMR-study with a population of 300 asymptomatic, diabetic (n=51) and healthy (n=249) volunteers matched to the same prevalence of cardiovascular risk factors. All subjects (64±7 years; 33% female) underwent CMR imaging including cine sequences, myocardial stress and rest first pass perfusion and T1 weighted inversion recovery gradient echo sequences. In the first part of our project we will analyse the CMR data in order to quantitatively assess left ventricular function and volumes, wall motion abnormalities and late gadolinium enhancement. Stress-induced myocardial ischemia will be analysed visually and semi-quantitatively. Based on the American Heart Association 17-segment model, the prevalence of findings will be documented and compared between diabetics and non-diabetics. To determine the prognostic significance of CMR findings, the occurrence of MACE has been and is still being monitored. In order to scrutinize the added value of CMR-findings as a prognostic tool, a comparison with clinically established risk factors derived from medical history, physical examination, blood tests, and electron beam computed tomography-calcium scoring will be conducted for both groups separately. Therefore, we will perform regression analyses to determine the association with these established risk factors. In daily clinical routine, CMR already is an established and vital tool for the assessment of cardiovascular pathologies. This cohort study will confirm whether the results of previous studies on symptomatic diabetics, concerning the high prognostic relevance of CMR findings, can be applied to asymptomatic diabetics. If we are successful in substantiating the added value of CMR findings as a predictive tool for MACE in asymptomatic diabetics and non-diabetics, the significance of CMR as a risk-stratification-tool would be further strengthened.

• DFG Programme: Research Grants