The Breisgau Pheno Heart Study

Coronary heart disease and its acute complication, myocardial infarction (MI), represent the leading causes of death in Europe and the United States. Although novel treatment strategies have helped to improve survival in patients with MI, a large proportion of patients develops heart failure and is at risk of life-threatening arrhythmias. Complications arising after MI constitute a severe burden not only for the patients themselves, but also for health care systems worldwide.

The likelihood of these complications depends on the area of myocardial tissue lost and the process of myocardial repair and scar tissue formation after MI ('remodeling') which are modified by the local and systemic immune response after MI. The immune response is critical after myocardial infarction. In particular, sustained overactive and prolonged inflammatory reactions lead to accentuated myocardial damage and dysfunction. Important mediators of the inflammatory reaction after MI are monocytes, T-cells, B-cells and hematopoietic stem and progenitor cells. Following MI, myeloid cells derived from the hematopoietic system drive a sharp increase in systemic leukocyte levels that correlates closely with mortality. T- and B-cells in particular act in response to specific antigens. Most of the data regarding the inflammatory response after MI, however, are derived from animal models. The immunological phenotypes after MI and their association with clinical outcome in humans are insufficiently characterized.

Aims: The aim of this project is to provide establish clinically and immunologically well-characterized cohort of patients after MI This will aid in identifying novel prognostic cellular and humoral biomarkers that may be used to identify patients at a high inflammatory and immune risk and to guide clinical management. Furthermore, these mediators, in the future, may be targeted by novel antigen-specific immunomodulatory approaches.

Patients with myocardial infarction (STEMI and NSTEMI) will be recruited after PCI within 24h and receive a structured follow-up. Clinical read-outs include a detailed and standardized patient history, clinical examination, standard blood work, coronary angiography, ECG, echocardiography and for subgroups, MRI. Patients will present for study visits at 6 weeks, 3 months and 12 months after the initial event. Blood will be sampled at the inclusion and during follow-up visits. Peripheral blood mononuclear cells and plasma will be stored at the Cardiovascular BioBank (CVBB) and FREEZE, both institutions at the University Hospital in Freiburg. Major adverse cardiac events (myocardial infarction, stroke, hospitalization for heart failure, cardiovascular death) will be recorded using telephone interviews and standardized queries to the local authorities. Several laboratory read-outs are planned including flow cytometry, mass cytometry, single cell RNA sequencing, T cell and B cell receptor sequencing and bulk-RNA-sequencing. In an initial approach we aim to recruit 400 patients with MI, of which we expect ≈40 to develop ischemic cardiomyopathy. Differences in immunological profiles between patients that develop MI and a propensity-matched control group will then be analyzed and correlated with clinical outcome data.