The impact of the large variability of SBP/DBP needs to be taken in to account when hypertension is diagnosed and when considering what represents ‘‘BP control’’ under treatment. Most importantly, we need to learn more about the relationship between BP variability and cardiovascular outcomes plus the effect of specific drug treatments on blood pressure variability. Acute ST-elevation myocardial infarction is caused by occlusion of a coronary artery as a result of coronary atherosclerotic plaque disruption with superimposed luminal thrombus. Many plaque disruptions are initially covered by mural thrombi without causing clinical symptoms. These mural thrombi may organize over time, a process characterized by ingrowth of smooth muscle cells 10-Hydroxycamptothecin and overgrowth of endothelial cells. Organized mural thrombi may entirely be incorporated in the atherosclerotic lesion, whereby the integrity of the vessel wall is restored. These so called healed plaque ruptures are found very frequently in coronary arteries at autopsy. In other patients, atherosclerotic plaque disruption with mural thrombosis leads to a process of repeated or ongoing thrombosis, which ultimately results in an acute coronary syndrome. We recently described the composition and age of aspirated thrombi in a small cohort of STEMI patients treated with primary percutaneous coronary intervention within 6 h of onset of symptoms. We demonstrated that in approximately 50% of these STEMI patients, coronary thrombi were days or even weeks old. The aim of the present study is to establish the histopathological characteristics and age of material aspirated during primary PCI in a much larger consecutive STEMI population, to identify predictors of successful thrombus aspiration and thrombus age, and to confirm the concept that there is a heterogeneous time course of different processes leading to the occlusive thrombotic event. Information about baseline characteristics, procedural characteristics, angiographic characteristics,JQ-EZ-05 and the use of thrombus aspiration devices was obtained from the electronic database. Angiographic characteristics such as distal embolization, pre- and post-procedural TIMI flow, lesion length, and residual stenosis have been prospectively recorded by the operator by visual assessment immediately after the procedure. In this study informed patient consent was not acquired, because thrombus aspiration and the histopathological assessment of aspirated material were part of routine clinical practice. In addition, because of the study being part of routine clinical practice nor a formal waiver under the description of Record-based Research from or approval by the local Medical Ethical Committee were required for this study. In this study we report the histopathological characteristics of material obtained from a large consecutive cohort of STEMI patients treated with thrombus aspiration in adjunct to conventional primary PCI. Aspirated material could histopathologically be confirmed in 74% of the patients. The obtained thrombus material showed lytic or organized changes in 40% of the patients, indicating the thrombus is older than 24 hours in a significant proportion of STEMI patients with onset of symptoms less than 12 hours before. Therefore, the use of a thrombus aspiration device was non-standard clinical practice during the study period and the decision to perform thrombus aspiration was at the discretion of the operator.