Tampere Coronary Artery Disease and Sudden Cardiac Arrest Study

Inclusion Criteria: 1. Age \> 18 years 2. A patient who lives in the area of 'Wellbeing Services County of Pirkanmaa' and seeks treatment for coronary artery disease (CAD). 3. CAD is diagnosed with invasive coronary angiogram or computed tomography angiogram (CTA) which is evaluated by cardiologists based on current guidelines for stenosis level evaluation and fractional flow reserve (FFR) results. 4. An invasive coronary angiogram or CTA is done within three (3) months. 5. Good or moderate everyday functional ability Exclusion Criteria: 1. Life expectancy \<1 months. 2. A significant valvular heart disease treated previously (endovascular or surgical) or requires treatment (endovascular or surgical) in the next three (3) months. 3. Previously implanted cardioverter-defibrillators (ICD) or will be implanted in the next three (3) months. 4. An active malignancy (ongoing treatment for a solid tumour, metastatic solid tumour, fast progressing haematological malignancy, or equal malignant disease). 5. A significant neurodegenerative disease (dementia, Mini-Mental State Examination (MMSE) \<23 or equivalenneurodegenerative disease affecting everyday functional ability, like ALS, myositis, prograded MS-disease or Parkinson's disease). 6. Intellectual disability or a significant disability affecting cognitive functions 7. Do-not-resuscitate (DNR) treatment decision Subgroup with blood samples: Blood samples are withdrawn from all study subjects under 76 years of age. Additionally, PaxGene samples are withdrawn from i) all study subjects under 65 years of age and ii) subjects between 65-76 years, if they have detected QRS-time\>110ms in the latest ECG.