Segmental peri-coronary epicardial adipose tissue volume and coronary plaque characteristics.

AIMS: Epicardial adipose tissue (EAT) has been proposed to modulate underlying coronary plaque features. The study aimed to determine the relation between segmental EAT (sEAT) volume, assessed by cardiac magnetic resonance (CMR), and underlying coronary plaque characteristics, as estimated by multidetector computed tomography (CT) (MDCT). METHODS AND RESULTS: The study included 32 male patients with stable angina pectoris and 11 age-matched healthy controls. For each CAD patient, sEAT volume around 8 coronary segments (3 in left anterior descending artery, 3 in right coronary artery, and 2 in left circumflex artery) was quantified by CMR. By MDCT, plaques in each coronary segment were characterized in terms of plaque volume, type, CT attenuation, and severity of luminal stenosis. Serum levels of adipokines were measured. Total EAT volume was significantly higher in CAD patients than in control group. Serum resistin showed significant correlation with EAT volume (r = 0.69, P < 0.001). Analysis of 256 coronary segments showed larger sEAT volume with increasing luminal stenosis of the corresponding segment (mild: 8.2 cm(3); moderate: 11 cm(3); severe: 11.8 cm(3), P < 0.001). sEAT volume was larger in segments with mixed than those with calcified or non-calcified plaques (12.1 vs. 10.2 vs. 9.5 cm(3), respectively, P = 0.015). sEAT volume was larger in segments with low CT attenuation non-calcified plaques compared with non-calcified plaques with CT attenuation >30 HU (10.5 vs. 8.2 mm(3), P < 0.001). CONCLUSION: Peri-coronary epicardial adipose tissue volume is significantly associated with the extent and severity of coronary atherosclerosis and may be a determinant of plaque vulnerability.

Restrictive right ventricular performance assessed by cardiac magnetic resonance after balloon valvuloplasty of critical pulmonary valve stenosis.

BACKGROUND: Little data are published about right ventricular diastolic performance in patients with critical pulmonary valve stenosis after balloon pulmonary valvuloplasty thus far. METHODS: A total of 44 patients with isolated critical pulmonary valve stenosis who had undergone balloon valvuloplasty with haemodynamic recordings were enrolled to the study; 33 patients who came for follow-up underwent further imaging by echocardiography after 6 months and their right ventricular functional parameters were compared with 33 control patients of the same age and sex. Out of 33 patients, 21 underwent cardiac MRI with late gadolinium enhancement to assess the presence of right ventricular fibrosis. RESULTS: The right ventricular systolic pressure (p<0.0001) and right ventricular outflow tract gradient (p<0.0001) decreased acutely (p<0.0001) after balloon valvuloplasty. During follow-up, M-mode left ventricular end diastolic dimension (p<0.001) and end systolic dimension increased (p<0.001), whereas right ventricular end diastolic dimension decreased (p<0.001). Compared with controls, patients (n=33) had significantly reduced tricuspid annular Ea and higher E/Ea (p<0.001). Right ventricular systolic dysfunction was also suggested by reduced tricuspid annular systolic velocity (p<0.001). Late gadolinium enhancement was demonstrated in 13 out of 21 patients with restrictive physiology, which involves the anterior right ventricular outflow tract, anterior wall, and inferior wall. The right ventricular late gadolinium enhancement score correlated positively with age (r=0.7, p<0.001) and right ventricular mass index (r=0.52, p<0.001). CONCLUSION: The persistence of right ventricular diastolic dysfunction after relief of chronic pressure overload of critical pulmonary valve stenosis suggests that a factor - other than increase in afterload - is involved in this physiology. Fibrosis is the most likely factor responsible for persistence of restrictive physiology as documented by late gadolinium enhancement.

Antegrade flow in Anomalous Left Coronary Artery from Pulmonary Artery: Clinical implications.

Anomalous origin of the left main coronary artery from the pulmonary artery (ALCAPA) is a rare congenital anomaly that usually presents in childhood. It results in left ventricular (LV) ischemia with resulting LV dysfunction. This ischemia results from retrograde flow into the pulmonary artery which can act as a coronary steal. We here report antegrade flow detected in ALCAPA caused by severe pulmonary hypertension. Anatomic correction of ALCAPA is the preferred surgical option and should be performed as early as possible.

Radiation in medicine: Origins, risks and aspirations.

The use of radiation in medicine is now pervasive and routine. From their crude beginnings 100 years ago, diagnostic radiology, nuclear medicine and radiation therapy have all evolved into advanced techniques, and are regarded as essential tools across all branches and specialties of medicine. The inherent properties of ionizing radiation provide many benefits, but can also cause potential harm. Its use within medical practice thus involves an informed judgment regarding the risk/benefit ratio. This judgment requires not only medical knowledge, but also an understanding of radiation itself. This work provides a global perspective on radiation risks, exposure and mitigation strategies.

Lessons from patient-specific 3D models of the cardiac chambers after the Mustard operation.

The recent ability to create detailed 3D models of the atrial and ventricular chambers using CT, MRI and rapid prototyping offers unique opportunities to study the size and shape of the different cardiac chambers both before and following operation for complex cardiac anomalies. We here describe the techniques for creating detailed 3D models of the heart and demonstrate the utility of these techniques in a patient studied after the Mustard operation. This can give important insights into the changes in size and shape of the different chambers and the patterns of blood flow from the pulmonary and systemic veins to the 'appropriate' ventricle. This information in turn could be extremely helpful in understanding and optimizing the overall hemodynamic function after the Mustard operation.

Integrated morphologic and functional assessment of the aortic root after different tissue valve root replacement procedures.

OBJECTIVES: This study was undertaken to explore aspects of the hemodynamic function of different biologic tissue aortic valve root replacements. We set out to image and display the spatiotemporal distributions of axially directed blood velocity through the aortic root. METHODS: The flow velocities through a plane transecting the aortic root were measured by 2-dimensional cine phase-contrast magnetic resonance velocity mapping in 44 subjects: 29 patients who had undergone aortic root replacement approximately 10 years previously (13 autografts, 10 stentless xenografts, and 6 homografts) and 15 healthy control subjects. With cine as well as velocity images, aortic sinus dimensions, effective orifice area, and several velocity parameters were measured. Color-coded plots of velocity relative to the sinus cross sections and velocity-time plots were used to compare spatiotemporal distributions of velocity. RESULTS: Peak flow velocity was similar between the autografts (102 ± 28.0 cm/s) and control valves (119 ± 20.0 cm/s) but was higher in xenografts (167 ± 36.0 cm/s) and homografts (206 ± 91.0 cm/s). These measurements showed an inverse relationship with the effective orifice area (7.27 ± 0.20, 4.24 ± 0.81, 3.37 ± 0.32, and 3.28 ± 0.87 cm(2), respectively). Autograft peak flow velocity showed no significant difference from control valve peak flow velocity, despite larger root dimensions (P < .001). The graphic displays provided further spatiotemporal information. CONCLUSIONS: Peak velocities and spatiotemporal flow patterns depend on the type of valve substitute. In the parameters measured, autograft replacements differed least from normal aortic valves.