From Stenting to Preventing Invasive and Long-term Treatment for Coronary Artery Disease in Sweden

Abstract: Coronary artery disease (CAD) is the leading cause of death worldwide. Treatment with coronary interventions, long-term treatment and life style changes can reduce symptoms and improve prognosis. The aim of this thesis was to investigate aspects of invasive treatment for multivessel coronary artery disease, and to investigate adherence to prevention guidelines one year after myocardial infarction. We used the national quality registry SWEDEHEART to collect data on long term treatment one year after myocardial infarction for 51 620 patients < 75 years of age. For 17 236 of the patients, we collected LDL-cholesterol measurements from SWEDEHEART and defined use of lipid lowering drugs from the Prescribed Drug Register. We developed a questionnaire for post-PCI-patients to investigate patients’ understanding of cause and treatment of coronary artery disease. For 23 342 PCI-patients with multivessel coronary artery disease, SWEDEHEART-data was linked to Swedish health data registries to determine one year outcome for patients undergoing incomplete vs. complete revascularization.  Lipid control (LDL-cholesterol < 1.8 mmol/L) was attained by one in four patients one year after myocardial infarction, whereas blood pressure control (< 140 mmHg) was attained by two thirds of patients. Lipid and blood pressure control was lower for women but there was no gender difference in smoking cessation rate: 56 %. Over 90 % of patients were treated with a statin after myocardial infarction but treatment was intensified for only one in five patients with LDL-cholesterol above target.The questionnaire study revealed that non-modifiable factors such as age and heredity were more often seen as cause of coronary artery disease than modifiable life style factors. Only one in five patients perceived CAD as a chronic illness, requiring life style changes.Two thirds of PCI-patients with multivessel disease underwent incomplete revascularisation, and this was associated with a twofold risk for the combination of death, myocardial infarction and repeat revascularization up to one year, compared to patients who underwent complete revascularization.We conclude that  long term treatment after myocardial infarction is suboptimal in relation to guideline recommendations. Assessment of patients’ views on CAD and better health education post PCI may facilitate life style changes. Further studies need to investigate whether complete revascularization will improve outcome for PCI-patients with multivessel disease.