Spontaneous Coronary Artery Dissection: Rediscovering an Old Cause of Myocardial Infarction

Spontaneous coronary artery dissection is an uncommon, but not insignificant cause of acute coronary syndrome that overwhelmingly affects middle-aged women. The pathophysiology of coronary dissection appears to be an outside-in mechanism, where the initiating event is not an intimal tear but rather the formation of an intramural hematoma, which compromises blood flow by reducing the arterial lumen. Considering this mechanism, it is clear to see how intracoronary imaging techniques, such as optical coherence tomography and intravascular ultrasound, are most accurate in the diagnosis. However, they carry a high rate of complications and are therefore generally avoided when the clinical scenario and angiographic appearance both support the diagnosis of spontaneous coronary artery dissection. The natural history of the disease is toward healing of the vessel wall and restoration of blood flow. Therefore, conservative medical management is the preferred approach unless there are high-risk factors such as hemodynamic instability, signs of ischemia and severe proximal or multivessel lesions, in which percutaneous or surgical revascularization should be considered. Perioperative evaluation of these patients must take into account several aspects of this disease. Most of these patients will be receiving single or dual antiplatelet therapy, so one must consider the timing of the event and the surgical hemorrhagic risk when deciding to stop these therapies. Extracoronary vascular disease also must be assessed because it can have an effect on patient monitoring and risk of postoperative complications.

Reporting standards for endovascular aortic repair of aneurysms involving the renal-mesenteric arteries

Endovascular aortic aneurysm repair of complex aortic aneurysms requires incorporation of side branches using specially designed aortic stent grafts with fenestrations, directional branches, or parallel stent grafts. These techniques have been increasingly used and reported in the literature. The purpose of this document is to clarify and to update terminology, classification systems, measurement techniques, and end point definitions that are recommended for reports dealing with endovascular repair of complex abdominal and thoracoabdominal aortic aneurysms involving the renal and mesenteric arteries.

Improving clinical practice guidelines for practicing cardiologists

Cardiac-related clinical practice guidelines have become an integral part of the practice of cardiology. Unfortunately, these guidelines are often long, complex, and difficult for practicing cardiologists to use. Guidelines should be condensed and their format upgraded, so that the key messages are easier to comprehend and can be applied more readily by those involved in patient care. After presenting the historical background and describing the guideline structure, we make several recommendations to make clinical practice guidelines more user-friendly for clinical cardiologists. Our most important recommendations are that the clinical cardiology guidelines should focus exclusively on (1) class I recommendations with established benefits that are supported by randomized clinical trials and (2) class III recommendations for diagnostic or therapeutic approaches in which quality studies show no benefit or possible harm. Class II recommendations are not evidence based but reflect expert opinions related to published clinical studies, with potential for personal bias by members of the guideline committee. Class II recommendations should be published separately as "Expert Consensus Statements" or "Task Force Committee Opinions," so that both majority and minority expert opinions can be presented in a less dogmatic form than the way these recommendations currently appear in clinical practice guidelines.