Estimates of lifetime attributable risk of cancer after a single radiation exposure from 64-slice computed tomographic coronary angiography.

AIMS: To estimate the life attributable risk (LAR) of cancer incidence over a wide range of dose radiation exposure and a large spectrum of possible diagnostic computed tomographic coronary angiography (CTCA) scenarios. METHODS: This study included 561 consecutive patients who underwent a successful prospective ECG-gating CTCA protocol (low-dose group) 64-slice CTCA and 188 patients who underwent retrospective ECG-gating CTCA with ECG-triggered dose modulation CTCA (high-dose group). LAR was computed, given the organ equivalent dose, for all cancers in both sexes. LAR was tabulated for each decile of dose-length product by 10-year age classes, separately for each sex. RESULTS: Estimates of LAR of any cancer for an exposure at age < or =40 year were lower in males than in females for any given quantile. At age >/ or =50 years, LAR was similar between sexes only at the lowest exposure doses, whereas at higher dosage, it was, in general, higher for women. At the median age of this case series (62 years) and for a radiation exposure ranging from 1.33 to 3.81 mSv, LAR was 1 in 4329 (or 23.1 per 10(5) persons exposed) and 1 in 4629 (or 21.6 per 10(5) persons) in men and women, respectively. For an exposure ranging from 10.34 to 18.97 mSv at the same median age, the LAR of cancer incidence was 1 in 1336 (or 74.8 per 10(5) persons) in men and doubled (1 in 614 or 162.8 per 10(5) persons) in women. CONCLUSIONS: This study provided an estimate of the LAR of cancer in middle-aged patients of both sexes after a single diagnostic CTCA, providing an easy-to-read table.

Relation between coronary atherosclerotic plaques and traditional risk factors in people with no history of cardiovascular disease undergoing multi-detector computed coronary angiography.

AIMS: To prospectively investigate the prevalence of coronary artery plaques (CAP) as detected by computed tomography-based angiography in a large number of consecutive individuals with no history of coronary artery disease (CAD) or acute coronary syndrome; to evaluate whether traditional risk factors are related to prevalence of CAP and to the expected 10-year risk of first major or fatal cardiovascular event (CVE). DESIGN: Prospective, single-centre, cross-sectional study. SETTING: The division of Cardiology at Fondazione Cardiocentro Ticino Lugano, Switzerland. METHODS: We prospectively included 920 consecutive individuals with no history of CAD who underwent computed tomography coronary angiography (CTCA). Risk estimation of fatal and non-fatal CVE was assessed using Global Assessment Risk (GAR) and Systematic Coronary Risk Evaluation (SCORE), respectively. Logistic regression was used to assess the association of risk factors with the prevalence of CAP. RESULTS: CAP was found in 459 (49.9%) individuals. Older age, higher body mass index, male gender, diabetes, hypertension and dyslipidaemia all increased the likelihood of the CAP burden at univariable analysis (p<0.001). At the multivariable analysis older age, male gender, hypertension and diabetes independently increased the likelihood of CAP burden (p<0.001). An increase in likelihood of CAP was observed in the presence of one, two and three or more risk factors and with an increasing value of GAR and SCORE. Notably, about 18% of subjects with CAP did not report any traditional risk factors and among individuals without CAPs, 12% had three or more risk factors. CONCLUSIONS: A direct relation between the prevalence of CAP, number of risk factors and the related 10-year risk of CVE was found. 18% of subjects without risk factors had CAP. In these individuals CTCA may help in further optimising the risk reduction strategies on an individual basis.

Assessment of right ventricular function by strain rate imaging in chronic obstructive pulmonary disease.

The purpose of the current study was to compare right ventricular (RV) myocardial wall velocities (tissue Doppler imaging) and strain rate imaging (SRI) parameters with conventional echocardiographic indices evaluating RV function in chronic obstructive pulmonary disease (COPD) patients. In total, 39 patients with COPD and 22 healthy subjects were included in the current study. Seventeen patients had pulmonary artery pressure <35 mmHg (group I) and 22 patients had pulmonary artery pressure >35 mmHg (group II). Tissue Doppler imaging, strain and strain rate (SR) values were obtained from RV free wall (FW) and interventricular septum. Respiratory function tests were performed (forced expiratory volume in one second/vital capacity (FEV(1)/VC) and carbon monoxide diffusion lung capacity per unit of alveolar volume (D(L,CO)/V(A))). Strain/SR values were reduced in all segments of group II patients compared with group I patients and controls with lowest values at basal FW site. A significant relationship was shown between peak systolic SR at basal FW site and radionuclide RV ejection fraction. A significant relationship was shown between peak systolic SR at basal FW site and D(L,CO)/V(A) and FEV(1)/VC. In conclusion, in chronic obstructive pulmonary disease patients, strain rate imaging parameters can determine right ventricular dysfunction that is complementary to conventional echocardiographic indices and is correlated with pulmonary hypertension and respiratory function tests.

Assessment of severity of mechanical prosthetic mitral regurgitation by transoesophageal echocardiography.

OBJECTIVE: To evaluate the ability of colour Doppler transoesophageal echocardiography (TOE) to assess quantitatively prosthetic mitral valve insufficiency. METHODS: 47 patients were studied with multiplane TOE and cardiac catheterisation. Proximal jet diameter was measured as the largest diameter of the vena contracta. Regurgitant area was measured by planimetry of the largest turbulent jet during systole. Flow convergence zone was considered to be present when a localised area of increased systolic velocities was apparent on the left ventricular side of the valve prosthesis. Pulmonary vein flow velocity was measured at peak systole and diastole. RESULTS: Mean (SD) proximal jet diameter was 0.63 (0.16) cm, with good correlation with angiographic grades (r = 0.83). Mean (SD) maximum colour jet area was 7.9 (2.5) cm2 (r = 0.69) with worse correlation if a single imaging plane was used for measurements (r = 0.62). The ratio of systolic to diastolic peak pulmonary flow velocity averaged 0.7 (1.3) cm (r = -0.66) with better correlation (r = -0.71) if patients with atrial fibrillation were excluded. Mean (SD) regurgitant flow rate was 168 (135) ml/s and regurgitant orifice area was 0.56 (0.43) cm2, with good correlation with angiography (r = 0.77 and r = 0.78, respectively). CONCLUSIONS: TOE correctly identified angiographically severe prosthetic mitral regurgitation, mainly by the assessment of the flow convergence region and the proximal diameter of the regurgitant jet.