Impact of Aortic Valve Replacement on Outcome of Symptomatic Patients with Severe Aortic Stenosis with Low Gradient and Preserved Left Ventricular Ejection Fraction
Alper Ozkan, Rory Hachamovitch, Samir R. Kapadia, E. Murat Tuzcu, and Thomas H. Marwick
Circulation. Originally published June 27, 2013. doi: 10.1161/CIRCULATIONAHA.112.001094

Impact of cardiac magnetic resonance imaging on human lymphocyte DNA integrity.

Impact of cardiac magnetic resonance imaging on human lymphocyte DNA integrity.


Magnetic resonance (MR) imaging is widely used for diagnostic imaging in medicine as it is considered a safe alternative to ionizing radiation-based techniques. Recent reports on potential genotoxic effects of strong and fast switching electromagnetic gradients such as used in cardiac MR (CMR) have raised safety concerns. The aim of this study was to analyse DNA double-strand breaks (DSBs) in human blood lymphocytes before and after CMR examination.


In 20 prospectively enrolled patients, peripheral venous blood was drawn before and after 1.5 T CMR scanning. After density gradient cell separation of blood samples, DNA DSBs in lymphocytes were quantified using immunofluorescence microscopy and flow cytometric analysis. Wilcoxon signed-rank testing was used for statistical analysis. Immunofluorescence microscopic and flow cytometric analysis revealed a significant increase in median numbers of DNA DSBs in lymphocytes induced by routine 1.5 T CMR examination.


The present findings indicate that CMR should be used with caution and that similar restrictions may apply as for X-ray-based and nuclear imaging techniques in order to avoid unnecessary damage of DNA integrity with potential carcinogenic effect.

The United States Registry for Fibromuscular Dysplasia: results in the first 447 patients.

The United States Registry for Fibromuscular Dysplasia: results in the first 447 patients.

Circulation. 2012 Jun 26;125(25):3182-90. doi: 10.1161/CIRCULATIONAHA.112.091223. Epub 2012 May 21.

The United States Registry for Fibromuscular Dysplasia: results in the first 447 patients.


Mount Sinai School of Medicine, One Gustave L. Levy Place, Box 1033, New York, NY 10029, USA.



Fibromuscular dysplasia (FMD), a noninflammatory disease of medium-size arteries, may lead to stenosis, occlusion, dissection, and/or aneurysm. There has been little progress in understanding the epidemiology, pathogenesis, and outcomes since its first description in 1938.


Clinical features, presenting symptoms, and vascular events are reviewed for the first 447 patients enrolled in a national FMD registry from 9 US sites. Vascular beds were imaged selectively based on clinical presentation and local practice. The majority of patients were female (91%) with a mean age at diagnosis of 51.9 (SD 13.4 years; range, 5-83 years). Hypertension, headache, and pulsatile tinnitus were the most common presenting symptoms of the disease. Self-reported family history of stroke (53.5%), aneurysm (23.5%), and sudden death (19.8%) were common, but FMD in first- or second-degree relatives was reported only in 7.3%. FMD was identified in the renal artery in 294 patients, extracranial carotid arteries in 251 patients, and vertebral arteries in 82 patients. A past or presenting history of vascular events were common: 19.2% of patients had a transient ischemic attack or stroke, 19.7% had experienced arterial dissection(s), and 17% of patients had an aneurysm(s). The most frequent indications for therapy were hypertension, aneurysm, and dissection.


In this registry, FMD occurred primarily in middle-aged women, although it presents across the lifespan. Cerebrovascular FMD occurred as frequently as renal FMD. Although a significant proportion of FMD patients may present with a serious vascular event, many present with nonspecific symptoms and a subsequent delay in diagnosis.