Defining motility in the Staphylococci

The ability of bacteria to move is critical for their survival in diverse environments and multiple ways have evolved to achieve this. Two forms of motility have recently been described for Staphylococcus aureus, an organism previously considered to be non-motile. One form is called spreading, which is a type of sliding motility and the second form involves comet formation, which has many observable characteristics associated with gliding motility. Darting motility has also been observed in Staphylococcus epidermidis. This review describes how motility is defined and how we distinguish between passive and active motility. We discuss the characteristics of the various forms of Staphylococci motility, the molecular mechanisms involved and the potential future research directions

ACC/AHA 2006 Guidelines for the Management of Patients With Valvular Heart Disease. A Report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines (Writing Committee to Revise the 1998 Guidelines for the Management of Patients With Valvular Heart Disease)

"The ACC and the AHA have long been involved in the joint development of practice guidelines designed to assist healthcare providers in the management of selected cardiovascular disorders or the selection of certain cardiovascular procedures. The determination of the disorders or procedures to develop guidelines for is based on several factors, including importance to healthcare providers and whether there are sufficient data from which to derive accepted guidelines. One important category of cardiac disorders that affect a large number of patients who require diagnostic procedures and decisions regarding long-term management is valvular heart disease. During the past 2 decades, major advances have occurred in diagnostic techniques, the understanding of natural history, and interventional cardiology and surgical procedures for patients with valvular heart disease. These advances have resulted in enhanced diagnosis, more scientific selection of patients for surgery or catheter-based intervention versus medical management, and increased survival of patients with these disorders. The information base from which to make clinical management decisions has greatly expanded in recent years, yet in many situations, management issues remain controversial or uncertain. Unlike many other forms of cardiovascular disease, there is a scarcity of large-scale multicenter trials addressing the diagnosis and treatment of patients with valvular disease from which to derive definitive conclusions, and the information available in the literature represents primarily the experiences reported by single institutions in relatively small numbers of patients.

ACC/AHA/ASNC Guidelines for the Clinical Use of Cardiac Radionuclide Imaging—Executive Summary: A Report of the American College of Cardiology/American HeartAssociation Task Force on Practice Guidelines (ACC/AHA/ASNC Committee to Revise the 1995 Guidelines for the Clinical Use of Cardiac Radionuclide Imaging)

The American College of Cardiology (ACC)/American Heart Association (AHA) Task Force on Practice Guidelines regularly reviews existing guidelines to determine when an update or full revision is needed. Guidelines for the Clinical Use of Cardiac Radionuclide Imaging were originally published in 1986 and updated in 1995. Important new developments have continued to occur since 1995, particularly in the areas of acute and chronic ischemic syndromes and heart failure. The Task Force therefore believed the topic should be revisited de novo and invited the American Society for Nuclear Cardiology (ASNC) to cosponsor the undertaking, which represents a joint effort of the 3 organizations

Management of Mitral Regurgitation in a Patient Contemplating Pregnancy

Management of rheumatic mitral regurgitation in a woman contemplating pregnancy presents unique challenges for the clinician. When tasked with taking care of this type of patient, attention needs to be paid to the patient’s functional status to determine if symptoms are present. In addition to this clinical assessment, transthoracic echocardiography is also critical. It provides insight into the etiology of the mitral regurgitation, assesses for the presence of concomitant mitral stenosis or other valvular abnormalities, characterizes the severity of mitral regurgitation through an integrative approach and identifies high risk findings including progressive left ventricular (LV) dilation and LV dysfunction. Surgical intervention is recommended for symptomatic patients and in asymptomatic patients with evidence of progressive LV dilation and a LV ejection fraction of less than 60%. While the presence of pulmonary hypertension and atrial fibrillation have been shown to be risk factors in degenerative mitral regurgitation, the same has not been demonstrated in rheumatic mitral valve disease. While mitral regurgitation may be reasonably well tolerated during pregnancy, symptomatic patients are at higher risk for adverse maternal and fetal outcomes, and therefore, it is recommended that mitral valve surgery be performed prior to pregnancy. Once the decision has been made to proceed to surgery, mitral repair, performed at a Heart Valve Center of Excellence is recommended if possible due to improved outcomes. Mitral valve repair is possible in >80% cases of rheumatic mitral regurgitation. If repair is not possible, replacement with either a bioprosthetic or mechanical valve are reasonable options. There are advantages and disadvantages to each approach and the choice of prosthesis should be a shared decision between the patient and her treatment team