Occult cardiotoxicity in childhood cancer survivors exposed to anthracycline therapy.

BACKGROUND: More than 50% of >270 000 childhood cancer survivors in the United States have been treated with anthracyclines and are therefore at risk of developing cardiotoxicity. Cardiac magnetic resonance (CMR) has demonstrated utility to detect diffuse interstitial fibrosis and changes in regional myocardial function. We hypothesized that CMR would identify occult cardiotoxicity characterized by structural and functional myocardial abnormalities in a cohort of asymptomatic pediatric cancer survivors with normal global systolic function. METHODS AND RESULTS: Forty-six long-term childhood cancer survivors with a cumulative anthracycline dose ≥200 mg/m(2) and normal systolic function were studied 2.5 to 26.9 years after anthracycline exposure. Subjects underwent transthoracic echocardiography, CMR with routine cine acquisition, tissue characterization, and left ventricular strain analysis using a modified 16-segment model. Extracellular volume was measured in 27 subjects, all of whom were late gadolinium enhancement negative. End-systolic fiber stress was elevated in 45 of 46 subjects. Low average circumferential strain magnitude (εcc) -14.9±1.4; P<0.001, longitudinal strain magnitude (εll) -13.5±1.9; P<0.001, and regional peak circumferential strain were seen in multiple myocardial segments, despite normal global systolic function by transthoracic echocardiography and CMR. The mean T1 values of the myocardium were significantly lower than that of control subjects at 20 minutes (458±69 versus 487±44 milliseconds; P=0.01). Higher mean extracellular volume was observed in female subjects (0.34 versus 0.22; P=0.01). CONCLUSIONS: Asymptomatic postchemotherapy pediatric patients have abnormal myocardial characteristics and strain parameters by CMR despite normal global cardiac function by standard transthoracic echocardiography and CMR measures.

Reduced Z-axis coverage multidetector CT angiography for suspected acute pulmonary embolism could decrease dose and maintain diagnostic accuracy.

Multidetector computed tomographic angiography (MDCTA) is the method of choice for evaluation of suspected acute pulmonary embolism (PE) in most patients because it is accurate and widely available. The use of computed tomography, including MDCTA for PE, has risen dramatically over the last several years with an attendant rise in radiation exposure. Many methods currently employed to reduce radiation dose may affect image quality and potentially affect diagnostic accuracy. Reducing Z-axis coverage would decrease radiation dose without any effect on image quality. This study was performed to assess the effect on the accuracy of MDCTA for suspected acute PE if the Z-axis coverage was reduced to the anatomic range from the top of the aortic arch through the heart. Two hundred ninety-five examinations were performed on a 64-detector-row MDCT and interpreted as positive for PE from July 2005 to February 2008. When the anatomic range of these data sets were retrospectively reduced and reinterpreted for PE, no case was interpreted as negative for PE. The Z-axis coverage was reduced by 37%. In the interest of keeping radiation doses as low as reasonably achievable, further research in this area is warranted.

Sonographically guided percutaneous radio frequency ablation of a renal cell carcinoma in a transplanted kidney.

Radio frequency ablation is an effective treatment for focal renal cell carcinoma (RCC). We report a patient with RCC in a transplanted kidney that was successfully treated with percutaneous sonographically guided radio frequency ablation.