Cyclooxygenase-1, not cyclooxygenase-2, is responsible for physiological production of prostacyclin in the cardiovascular system

Prostacyclin is an antithrombotic hormone produced by the endothelium, whose production is dependent on cyclooxygenase (COX) enzymes of which two isoforms exist. It is widely believed that COX-2 drives prostacyclin production and that this explains the cardiovascular toxicity associated with COX-2 inhibition, yet the evidence for this relies on indirect evidence from urinary metabolites. Here we have used a range of experimental approaches to explore which isoform drives the production of prostacyclin in vitro and in vivo. Our data show unequivocally that under physiological conditions it is COX-1 and not COX-2 that drives prostacyclin production in the cardiovascular system, and that urinary metabolites do not reflect prostacyclin production in the systemic circulation. With the idea that COX-2 in endothelium drives prostacyclin production in healthy individuals removed, we must seek new answers to why COX-2 inhibitors increase the risk of cardiovascular events to move forward with drug discovery and to enable more informed prescribing advice.     

The virtual dental home: implications for policy and strategy

Widely recognized problems with the U.S. health care system, including rapidly increasing costs and disparities in access and outcomes also exist in oral health. If oral health systems are to meet the "Triple Aim" of improving the experience of care, improving the health of populations, and reducing per capita costs of health care, new and innovative strategies will be needed including new regulatory, delivery, and financing systems. The virtual dental home is one such system.     

Primary percutaneous coronary intervention in acute myocardial infarction

Primary percutaneous coronary intervention (PCI) has emerged as the preferred therapy for acute ST-segment elevation myocardial infarction (STEMI), as multiple randomized clinical trials and pooled analyses have shown improved clinical outcomes compared with medical reperfusion. Unfortunately, medical centers with 24-hour PCI capability are concentrated in urban areas, relegating many patients in the United States to inferior medical reperfusion. Ongoing substantial research efforts are directed at optimizing mechanical reperfusion, including refinements in adjuvant medical therapy and the use of drug-eluting stents in the catheterization laboratory. Research efforts are also focusing on the implementation of streamlined transfer systems from community centers to tertiary care centers, akin to systems used in the trauma model. Furthermore, experience with the performance of primary PCI at community centers without onsite surgical backup is growing. This article summarizes data regarding the current state, challenges, and future directions of primary PCI for STEMI, emphasizing adherence to current American College of Cardiology/American Heart Association guidelines.     

An apical left ventricular aneurysm rupture presenting as left breast mass 11 years after surgical repair

Left ventricular (LV) pseudoaneurysm is a rare entity and, consequently, there is limited knowledge of the condition’s natural history. The most frequent mode of presentation for LV pseudoaneurysm is heart failure with chest pain. However, the variable presentation of this condition requires a high index of suspicion for diagnosis.We report the case of a 75-year-old woman who had suffered an acute myocardial infarction 23 years previously, which resulted in a calcified LV apical aneurysm. Three weeks prior to being referred to our hospital, she was noted by her general practitioner to have a left-sided breast mass although mammography was negative. One week later, she attended the accident and emergency department; she was haemodynamically unstable but was resuscitated successfully. Contrast enhanced computed tomography showed a large haematoma located in the left chest wall communicating with the left ventricle. She underwent emergency cardiac surgical repair. On arrival at the intensive care unit following surgery, her haemodynamic status was unstable, and she deteriorated rapidly and died.With this report, we aim to raise the level of awareness for an apical LV pulsatile mass that could anatomically expand and present as a breast mass or tumour. An early diagnosis and timely surgical intervention is essential in order to achieve better outcomes and avoid detrimental complications.     

Antithrombotic therapy during percutaneous coronary intervention

Ischemic complications of percutaneous coronary intervention occur commonly and are among the major limitations of the procedure. Both platelets and thrombin play an essential role in the response to the arterial injury that follows coronary intervention and in the pathophysiology of the ischemic complications of the procedure. Aspirin and heparin are essential treatments for the patient undergoing coronary intervention. Novel thrombin and platelet inhibitors are being developed that may be useful for improving both acute and long-term clinical outcomes of percutaneous coronary intervention.