Thromboembolic resolution assessed by CT pulmonary angiography after treatment for acute pulmonary embolism

The systematic assessment of residual thromboembolic obstruction after treatment for acute pulmonary embolism (PE) has been under-studied. This assessment is of potential clinical importance, should clinically suspected recurrent PE occur, or as tool for risk stratification of cardiopulmonary complications or recurrent venous thromboembolism (VTE). This study aimed to assess the rate of PE resolution and its implications for clinical outcome. In this prospective, multi-center cohort study, 157 patients with acute PE diagnosed by CT pulmonary angiography (CTPA) underwent follow-up CTPA-imaging after six months of anticoagulant treatment. Two expert thoracic radiologists independently assessed the presence of residual thromboembolic obstruction. The degree of obstruction at baseline and follow-up was calculated using the Qanadli obstruction index. All patients were followed-up for 2.5 years. At baseline, the median obstruction index was 27.5 %. After six months of treatment, complete PE resolution had occurred in 84.1 % of the patients (95 % confidence interval (CI): 77.4–89.4 %). The median obstruction index of the 25 patients with residual thrombotic obstruction was 5.0 %. During follow-up, 16 (10.2 %) patients experienced recurrent VTE. The presence of residual thromboembolic obstruction was not associated with recurrent VTE (adjusted hazard ratio: 0.92; 95 % CI: 0.2–4.1). This study indicates that the incidence of residual thrombotic obstruction following treatment for PE is considerably lower than currently anticipated. These findings, combined with the absence of a correlation between residual thrombotic obstruction and recurrent VTE, do not support the routine use of follow-up CTPA-imaging in patients treated for acute PE.

The Cognitive decline in Older Patients with End stage renal disease (COPE) study - rationale and design

BACKGROUND

Older patients with end stage renal disease (ESRD) are at increased risk for cognitive decline, but detailed studies of the magnitude of cognitive decline on dialysis or comprehensive conservative management (CCM) are lacking and the underlying pathophysiological mechanisms have poorly been studied.

OBJECTIVES

To describe the rationale and design of the COPE study. Study objectives are as follows. Firstly, to examine the severity of cognitive impairment in older patients reaching ESRD before dialysis and the rate of decline after dialysis or CCM initiation. Secondly, to study the association of blood biomarkers for microvascular damage and MRI derived measurements of small vessel disease with the rate of cognitive decline. Thirdly, to examine to what extent cardiac function is related to brain structure and perfusion in patients reaching ESRD. Finally, to study the association of cognitive and functional capacity with quality of life in pre-dialysis patients, as well as after dialysis or CCM initiation.

STUDY DESIGN AND METHODS

The COPE study is a prospective, multicenter cohort study in the Netherlands, including prevalent and incident pre-dialysis patients ≥65 years old with eGFR ≤20 ml/min/1.73 m², awaiting either dialysis or CCM initiation. At baseline extensive data is collected including a comprehensive geriatric assessment and laboratory tests. Brain and cardiac MRI for analysis of structural and functional abnormalities are performed at baseline and repeated following therapy change. All other measurements are repeated annually during four years of follow up, including an extra evaluation six months after initiation of dialysis.

CONCLUSIONS

Knowledge of the magnitude of cognitive decline and its underlying pathophysiological mechanism, as well as its impact on functionality and quality of life can eventually help to postulate an algorithm for well balanced decision making in treatment strategies in older patients reaching ESRD.

CLINICAL TRIAL REGISTRATION

The COPE study is registered on www.ccmo.nl (number: NL46389.058.13).

Predicting cardiopulmonary involvement in patients with systemic sclerosis: complementary value of nailfold videocapillaroscopy patterns and disease-specific autoantibodies

Objective

To evaluate the prevalence of anti-extractable nuclear antigen (anti-ENA) antibodies in Dutch SSc patients and the predictive power of the combination of specific anti-ENA antibodies and nailfold videocapillaroscopy (NVC) patterns to improve identification of patients with high risk for cardiopulmonary involvement.

Methods

A total of 287 patients (79%) from the Leiden SSc-Cohort had data available on NVC-pattern (no SSc-specific, early, active, late) and anti-ENA antibodies. Associations between anti-ENA/NVC combinations with cardiopulmonary parameters were explored using logistic regression.

Results

Prevalence of ACA was 37%, anti-Scl-70 24%, anti-RNP 9%, anti-RNAPIII 5%, anti-fibrillarin 4%, anti-Pm/Scl 3%, anti-Th/To 0.3% and anti-Ku 1.4%. NVC showed a SSc-specific pattern in 88%: 10% early, 42% active and 36% late. The prevalence of different NVC patterns was equally distributed among specific anti-ENA antibodies, except for the absence of early pattern in anti-RNP positive patients. Fifty-one percent had interstitial lung disease (ILD), 59% had decreased diffusion capacity for carbon monoxide and 16% systolic pulmonary artery pressure >35 mmHg (sPAP↑). Regardless of ENA-subtype, NVC-pattern showed a stable association with presence of ILD or sPAP↑. For ILD, the odds ratios (ORs) were 1.3-1.4 ( P < 0.05 for analyses with anti-RNAPIII, anti-RNP). For diffusion capacity for carbon monoxide, the OR was 1.5 ( P < 0.05 for analyses with ACA, anti-Scl-70, anti-RNAPIII, anti-RNP). For sPAP↑, the ORs were 2.2-2.4 ( P < 0.05 for analyses with anti-RNAPIII, anti-RNP).

Conclusion

In Dutch SSc patients, all SSc-specific auto-antibodies were found, with ACA and anti-Scl-70 being the most prevalent. Strikingly, the association between NVC-pattern and heart/lung involvement was independent of specific anti-ENA antibodies, which might indicate microangiopathy is an important cause of organ involvement.

The role of computed tomography in the diagnosis of acute and chronic pulmonary embolism

Pulmonary embolism (PE) is a potentially life threatening condition requiring adequate diagnosis and treatment. Computed tomography pulmonary angiography (CTPA) is excellent for including and excluding PE, therefore CT is the first-choice diagnostic imaging technique in patients suspected of having acute PE. Due to its wide availability and low invasiveness, CTPA tends to be overused. Correct implementation of clinical decision rules in diagnostic workup for PE improves adequate use of CT. Also, CT adds prognostic value by evaluating right ventricular (RV) function. CT-assessed RV dysfunction and to lesser extent central emboli location predicts PE-related mortality in normotensive and hypotensive patients, while PE embolic obstruction index has limited prognostic value. Simple RV/left ventricular (LV) diameter ratio measures >1.0 already predict risk for adverse outcome, whereas ratios <1.0 can safely exclude adverse outcome. Consequently, assessing the RV/LV diameter ratio may help identify patients who are potential candidates for treatment at home instead of treatment in the hospital. A minority of patients develop chronic thromboembolic pulmonary hypertension (CTEPH) following acute PE, which is a life-threatening condition that can be diagnosed by CT. In proximal CTEPH, involving the more central pulmonary arteries, thrombectomy usually results in good outcome in terms of both functional status and long-term survival rate. CT is becoming the imaging method of choice for diagnosing CTEPH as it can identify patients who may benefit from thrombectomy. New CT developments such as distensibility measurements and dual-energy or subtraction techniques may further refine diagnosis and prognosis for improved patient care.

Coronary or thoracic artery calcium score in provoked and unprovoked pulmonary embolism: a case-control study

Essentials Patients with unprovoked pulmonary embolism (PE) are at increased risk of arterial thromboembolism. Coronary and thoracic aorta calcium were evaluated in patients with and without (unprovoked) PE. No association was found between (unprovoked) PE and coronary or aortic calcification. Assessment of both calcium scores on computed tomography pulmonary angiography was highly reproducible.

SUMMARY

Objective To evaluate the potential association between (unprovoked) pulmonary embolism (PE) and the presence and extent of coronary artery calcium (CAC) and thoracic aorta calcium (TAC). Methods CAC and TAC derived from computed tomography pulmonary angiography of 100 patients with PE were compared to that of 100 patients in whom PE was ruled out. Results Intraobserver and interobserver agreements for both TAC and CAC were excellent (intraclass correlation > 0.95 for both). In patients with PE vs. patients without PE, no significant differences were found in the presence of CAC or TAC (CAC 64% vs. 67%, odds ratio [OR] 1.0, 95% confidence interval [CI] 0.67-1.6; TAC 46% vs. 59%, OR 1.2, 95% CI 0.80-2.1). Mean CAC and TAC scores were significantly lower in patients with PE than in patients without PE (CAC 3.4 vs. 4.9, absolute difference 1.5, 95% CI 0.2-2.8; TAC 1.1 vs. 1.8, absolute difference 0.9, 95% CI 0.2-1.2). No significant differences were found in the presence of CAC or TAC or in mean CAC and TAC scores between patients with unprovoked PE vs. patients with provoked PE, or between patients with unprovoked PE vs. no PE. Conclusion No significant differences were found between the extent of CAC and TAC in patients with unprovoked PE compared to those with provoked PE or without PE. The observed difference in the extend of CAC and TAC between patients with and without PE was dependent on prevalent cardiovascular risk factors.

Biplane versus short-axis measures of the left atrium and ventricle in patients with systolic dysfunction assessed by magnetic resonance

PURPOSE

This study aims to investigate if the time saving biplane method can be an alternative to short-axis measurements for left atrium (LA) and left ventricle (LV) in cardiac magnetic resonance of patients with extensive LV remodeling.

MATERIALS AND METHODS

In 45 patients with coronary artery disease and systolic LV dysfunction [ejection fraction (EF)<50%], LA and LV end-diastolic volume, end-systolic volume, stroke volume, and EF were measured by the biplane area length and by the short-axis volume method.

RESULTS

No statistical differences between the biplane area length and short-axis volume were found for the LA end-systolic or the LV end-diastolic volumes. However, the biplane area length method overestimated LA stroke volume by 7.1±12.3 ml, LA EF by 6.7±8.8% (both P<.001), LV stroke volume by 6.2±12.9 ml (P=.002), and LV EF by 2.6±4.6% (P<.001). The differences in LV measurements were more evident in patients with severely distorted LV. For LA volume parameters, overall consistency between biplane area length and short-axis approach was good [all intraclass correlation coefficient (ICC)≥0.74] and for LV volume parameters, overall consistency between both approaches was excellent (all ICC≥0.93).

CONCLUSION

In patients with LV systolic dysfunction, the short-axis volume is superior to the biplane method and should be the first choice, when accurate determination of LA and LV EF is the main clinical indication for cardiac magnetic resonance.

Therapeutic and diagnostic outcomes of a standardised, comprehensive care pathway for patients with systemic sclerosis

Objectives

To determine the outcomes, including number of medical interventions and initiation of immunosuppressive treatment of a standardised, comprehensive, diagnostic care pathway for patients with systemic sclerosis (SSc). Patient characteristics associated with need for medical interventions and with need for immunosuppressive treatment were determined.

Methods

Data were routinely gathered in connection with a 2-day care pathway combining multidisciplinary care and complete diagnostic work-up of organ involvement in SSc. The number of patients in whom the pathway resulted in medical interventions, and/or initiation of immunosuppressives was recorded. Patient characteristics and diagnostic tests results were compared between patients with and without medical interventions, and patients with and without initiation of immunosuppressives by means of multivariable logistic regression analyses.

Results

During a period of 44 months, 226 patients with SSc were referred to the care pathway. They included 186 (82%) women with mean age of 54 (SD 14.5) years, and median disease duration of 4 years (range 1–11); 73 (32%) of them had diffuse cutaneous SSc. Medical interventions were initiated in 191 (85%) patients, including initiation of immunosuppressive treatment in n=49 (22%). Presence of telangiectasias and higher erythrocyte sedimentation rate were associated with any medical intervention. Of commonly available variables, lower age, higher skin score and absence of anticentromere antibody were associated with initiation of immunosuppressives.

Conclusions

A standardised comprehensive 2-day care pathway for patients with SSc resulted in additional diagnostic or therapeutic interventions in 85% of the patients, regardless of SSc subtype and disease duration. In 22% of the patients, immunosuppressive treatment was initiated.

Coupling between MRI-assessed regional aortic pulse wave velocity and diameters in patients with thoracic aortic aneurysm: a feasibility study

AIMS

Thoracic aortic aneurysm (TAA) is potentially life-threatening and requires close follow-up to prevent aortic dissection. Aortic stiffness and size are considered to be coupled. Regional aortic stiffness in patients with TAA is unknown. We aimed to evaluate coupling between regional pulse wave velocity (PWV), a marker of vascular stiffness, and aortic diameter in TAA patients.

METHODS

In 40 TAA patients (59 ± 13 years, 28 male), regional aortic diameters and regional PWV were assessed by 1.5 T MRI. The incidence of increased diameter and PWV were determined for five aortic segments (S1, ascending aorta; S2, aortic arch; S3, thoracic descending aorta; S4, suprarenal and S5, infrarenal abdominal aorta). In addition, coupling between regional PWV testing and aortic dilatation was evaluated and specificity and sensitivity were assessed.

RESULTS

Aortic diameter was 44 ± 5 mm for the aortic root and 39 ± 5 mm for the ascending aorta. PWV was increased in 36 (19 %) aortic segments. Aortic diameter was increased in 28 (14 %) segments. Specificity of regional PWV testing for the prediction of increased regional diameter was ≥ 84 % in the descending thoracic to abdominal aorta and ≥ 68 % in the ascending aorta and aortic arch.

CONCLUSION

Normal regional PWV is related to absence of increased diameter, with high specificity in the descending thoracic to abdominal aorta and moderate results in the ascending aorta and aortic arch.

Genetically determined prospect to become long-lived is associated with less abdominal fat and in particular less abdominal visceral fat in men

PURPOSE

familial longevity is marked by an exceptionally healthy metabolic profile and low prevalence of cardiometabolic disease observed already at middle age. We aim to investigate whether regional body fat distribution, which has previously shown to be associated with cardiometabolic risk, is different in offspring of long-lived siblings compared with controls.

METHODS

our institutional review board approved the study, and all participants (n = 344, average age in years 65.6) gave written informed consent. Offspring (n = 175) of non-agenarian siblings were included. Their partners (n = 169) were enrolled as controls. For abdominal visceral adipose tissue (VAT) and subcutaneous adipose tissue (SAT) measurements, a single-slice 8.0 mm computed tomography (CT) acquisition was planned at the level of the 5th lumbar vertebra. In addition, participants underwent prospectively electrocardiography-triggered unenhanced volumetric CT of the heart. Abdominal VAT and SAT areas (cm(2)) and epicardial adipose tissue (EAT) volumes (ml) were acquired by semi-automated segmentation techniques. Linear regression analysis was performed adjusting for cardiovascular risk factors.

RESULTS

total abdominal fat areas were smaller in male offspring compared with controls (353.0 versus 382.9 cm(2), P = 0.022). The association between low abdominal VAT areas in male offspring (149.7 versus 167.0 cm(2) in controls, P = 0.043) attenuated after additional adjustment for diabetes (P = 0.078). Differences were not observed for females. EAT volumes were similar between offspring of long-lived siblings and controls.

CONCLUSION

males who have genetically determined prospect to become long-lived have less abdominal fat and in particular less abdominal VAT compared with controls.

Right ventricular cardiomyopathy meeting the arrhythmogenic right ventricular dysplasia revised criteria? Don't forget sarcoidosis!

A 53-year-old woman was referred for ventricular fibrillation with resuscitation. A CT-angiography showed signs of a right ventricular enlargement without obvious cause. A cardiac MRI demonstrated a dilated and hypokinetic right ventricle with extensive late gadolinium enhancement. Arrhythmogenic right ventricular dysplasia (ARVD) was suspected according to the "revised ARVD task force criteria". An endomyocardial biopsy was inconclusive. The patient developed purulent pericarditis after epicardial ablation therapy and died of toxic shock syndrome. The post-mortem pathologic examination demonstrated sarcoidosis involving the heart, lungs, and thyroid gland.

Visceral adipose tissue is associated with microstructural brain tissue damage

OBJECTIVE

Obesity has been associated with microstructural brain tissue damage. Different fat compartments demonstrate different metabolic and endocrine behaviors. The aim was to investigate the individual associations between abdominal visceral adipose tissue (VAT) and subcutaneous adipose tissue (SAT) and microstructural integrity in the brain.

METHODS

This study comprised 243 subjects aged 65.4 ± 6.7 years. The associations between abdominal VAT and SAT, assessed by CT, and magnetization transfer imaging markers of brain microstructure for gray and white matter were analyzed and adjusted for confounding factors.

RESULTS

VAT was associated with normalized MTR peak height in gray (β -0.216) and white matter (β -0.240) (both P < 0.01) after adjustment for confounding factors. After adjustment for sex, age, and descent, SAT was associated with normalized MTR peak height in gray and white matter, but not after additional correction for BMI, hypertension, current smoking, statin use, and type 2 diabetes (respectively, β -0.055 and β 0.035, both P > 0.05). Stepwise linear regression analysis showed that only VAT was associated with normalized MTR peak height in gray and white matter (both P < 0.001).

CONCLUSIONS

Our data indicate that increased abdominal VAT rather than SAT is associated with microstructural brain tissue damage in elderly individuals.

Characterization and improved quantification of left ventricular inflow using streamline visualization with 4DFlow MRI in healthy controls and patients after atrioventricular septal defect correction

PURPOSE

To evaluate trans-left atrioventricular valve (LAVV) blood flow and optimize left ventricular inflow quantification in healthy controls and patients after atrioventricular septal defect (AVSD) correction.

MATERIALS AND METHODS

Twenty-five patients after AVSD correction and 25 controls underwent 4DFlow MRI. Using streamline visualization in four- and two-chamber views, inflow direction at early and late filling was defined at the annulus level and at the peak inflow velocity (PIV) level. Trans-LAVV flow volume and velocity were assessed from a static 2D-multiplanar-reformat (MPR), a 4D-MPR tracking LAVV annulus and a 4D-MPR tracking the PIV-level, angulated perpendicular to the inflow.

RESULTS

In patients, on average 9° more laterally directed inflow was found at the PIV-level compared to controls. In controls, 4DFlow velocity mapping with LAVV annulus tracking resulted in lower absolute error with aortic flow (3 (1-8) mL) than with static 2D-MPR (7 (4-16) mL, P = 0.001). In patients, 4D-MPR tracking the PIV-level, resulted in lower absolute error with aortic flow (2 (1-4) mL) than with 4D-MPR LAVV annulus tracking (6 (2-10) mL, P = 0.003).

CONCLUSION

Streamline visualization of 4DFlow MRI data revealed dynamic trans-LAVV inflow and more lateral flow after AVSD correction. Streamline visualization improved trans-LAVV flow quantification as the positioning and angulation of the measurement plane was optimized, allowing an accurate assessment of left ventricular inflow.

Right ventricular function and thrombus load in patients with pulmonary embolism and diagnostic delay

INTRODUCTION

It has been reported that the time between symptom onset and objective diagnosis of pulmonary embolism (PE) does not affect patients' prognosis with regard to re-thrombosis and mortality risk. However, this observation is contra-intuitive and poorly understood. We further elaborated on this paradox by evaluating thrombus load and right ventricular function in patients with and without diagnostic delay.

MATERIALS AND METHODS

We performed a post hoc analysis of a previously published observational prospective outcome study in 113 consecutive PE patients. Qanadli-score and RV/LV ratio were scored in all patients, as was the duration from symptom onset to clinical presentation and diagnosis. Diagnostic delay was defined as a period of more than 7 days between symptom onset and clinical presentation. Further endpoints were mortality and hospital readmission in a 6-week follow-up period.

RESULTS

Twenty patients with and 93 patients without delay were studied, who had comparable baseline characteristics and co-morbidities. In linear analyses, Qanadli-score (R² of 0.021; P = 0.130) and RV/LV ratio (R² < 0.001; P = 0.991) were not associated with diagnostic delay. Likewise, longer delay was not predictive of 6-week mortality (odds ratio, 0.65; 95% CI, 0.08-5.57) or hospital readmission (odds ratio, 0.75; 95% CI, 0.15-3.65).

CONCLUSION

In our patient cohort, diagnostic delay was not associated with higher thrombus load or right ventricular dysfunction. This provides a possible explanation for the lack of prognostic relevance of diagnostic delay.

Hestia criteria can safely select patients with pulmonary embolism for outpatient treatment irrespective of right ventricular function

BACKGROUND

There has been debate over how patients with pulmonary embolism (PE) can be safely selected for outpatient treatment.

OBJECTIVES

To compare the Hestia criteria with the European Society of Cardiology (ESC) criteria for selecting low-risk patients with PE for outpatient treatment.

METHODS

From 2008 to 2010, 496 patients with acute, symptomatic PE were screened and 275 treated at home and 221 treated in the hospital according to the Hestia Study protocol. The Hestia criteria were used to select patients for outpatient treatment. Right and left ventricular (RV and LV) diameters were measured on computed tomography images. RV dysfunction was defined as an RV/LV ratio > 1.0. Patients were classified according to the ESC criteria into low, intermediate and high-risk groups, based on blood pressure and RV dysfunction. During 3 months follow-up adverse events were scored.

RESULTS

Adverse events occurred in 22 patients (4.5%) treated in the hospital vs. none of the patients treated at home (P < 0.001). Sensitivity and negative predictive value for adverse outcome were 100% for the Hestia criteria and 96% and 99% for the ESC criteria, respectively. Of the patients treated at home according to the Hestia criteria, 35% were normotensive but had RV dysfunction and were classified as intermediate risk according to the ESC criteria. No adverse events happened in these patients treated at home.

CONCLUSIONS

Clinical criteria, such as the Hestia criteria, could be helpful in selecting patients, including those with RV dysfunction who have a low risk of adverse clinical outcome and could be candidates for outpatient treatment.

MRI-assessed regional pulse wave velocity for predicting absence of regional aorta luminal growth in marfan syndrome

BACKGROUND

In patients with Marfan syndrome (MFS), increased aortic wall stiffening may lead to progressive aortic dilatation. Aortic Pulse Wave Velocity (PWV), a marker of wall stiffness can be assessed regionally, using in-plane multi-directional velocity-encoded MRI. This study examined the diagnostic accuracy of regional PWV for prediction of regional aortic luminal growth during 2-year follow-up in MFS patients.

METHODS

In twenty-one MFS patients (mean age 36 ± 15 years, 11 male) regional PWV and aortic luminal areas were assessed by 1.5 T MRI. At 2-year follow-up, the incidence of luminal growth, defined as mean luminal diameter increase >2mm was determined for five aortic segments (S1, ascending aorta; S2, aortic arch; S3, thoracic descending aorta, S4, supra-renal and S5, infra-renal abdominal aorta). Regional PWV at baseline was considered increased when exceeding age-related normal PWV (healthy volunteers (n=26; mean age 30 ± 10 years, 15 male)) by two standard-errors. Sensitivity and specificity of regional PWV-testing for prediction of regional luminal growth were determined.

RESULTS

Regional PWV at baseline was increased in 17 out of 102 segments (17%). Significant luminal growth at follow-up was reported in 14 segments (14%). The specificity of regional PWV-testing was ≥ 78% for all aortic segments, sensitivity was ≤ 33%.

CONCLUSIONS

Regional PWV was significantly increased in MFS patients as compared to healthy volunteers within similar age range, in all aortic segments except the ascending aorta. Furthermore, regional PWV-assessment has moderate to high specificity for predicting absence of regional aortic luminal growth for all aortic segments in MFS patients.

Evaluation of sampling density on the accuracy of aortic pulse wave velocity from velocity-encoded MRI in patients with Marfan syndrome

PURPOSE

To evaluate the effect of spatial (ie, number of sampling locations along the aorta) and temporal sampling density on aortic pulse wave velocity (PWV) assessment from velocity-encoded MRI in patients with Marfan syndrome (MFS).

MATERIALS AND METHODS

Twenty-three MFS patients (12 men, mean age 36 ± 14 years) were included. Three PWV-methods were evaluated: 1) reference PWV(i.p.) from in-plane velocity-encoded MRI with dense temporal and spatial sampling; 2) conventional PWV(t.p.) from through-plane velocity-encoded MRI with dense temporal but sparse spatial sampling at three aortic locations; 3) EPI-accelerated PWV(t.p.) with sparse temporal but improved spatial sampling at five aortic locations with acceleration by echo-planar imaging (EPI).

RESULTS

Despite inferior temporal resolution, EPI-accelerated PWV(t.p.) showed stronger correlation (r = 0.92 vs. r = 0.65, P = 0.03) with reference PWV(i.p.) in the total aorta, with less error (8% vs. 16%) and variation (11% vs. 27%) as compared to conventional PWV(t.p.) . In the aortic arch, correlation was comparable for both EPI-accelerated and conventional PWV(t.p.) with reference PWV(i.p.) (r = 0.66 vs. r = 0.67, P = 0.46), albeit 92% scan-time reduction by EPI-acceleration.

CONCLUSION

Improving spatial sampling density by adding two acquisition planes along the aorta results in more accurate PWV assessment, even when temporal resolution decreases. For regional PWV assessment in the aortic arch, EPI-accelerated and conventional PWV assessment are comparably accurate. Scan-time reduction makes EPI-accelerated PWV assessment the preferred method of choice.

Recovery of right and left ventricular function after acute pulmonary embolism

AIM

To evaluate recovery of cardiac function after acute pulmonary embolism (PE).

MATERIALS AND METHODS

Routine breath-held computed tomography (CT)-pulmonary angiography was performed in patients with suspected PE to confirm or exclude the diagnosis of PE at initial presentation. Electrocardiogram (ECG)-triggered cardiac CT was performed to assess biventricular function. After 6 months, cardiac magnetic resonance imaging (MRI) was performed. In total, 15 consecutive patients with PE and 10 without were studied. A significant change in ventricular volume was defined as a >15% change in end-diastolic or -systolic volumes (EDV, ESV), and significant ventricular function improvement as a >5% increase in ejection fraction (EF) as based on reported cut-off values.

RESULTS

Right and left ventricular (RV and LV) EDV and ESV changed non-significantly (<1.3%) in the patients without PE, indicating good comparability of those values measured by CT and MRI. PE patients with baseline normal RV function (RVEF ≥ 47%) revealed a >5% improvement in the RVEF (+5.4 ± 3.1%) due to a decrease in the RVESV. Patients with baseline abnormal RV function showed a >5% improvement in the RVEF (+14 ± 15%) due to decreases in both the RVESV and RVEDV. Furthermore, the LVEDV increased in this latter patient group.

CONCLUSIONS

The present study demonstrated an improvement in RV function in the majority of patients with PE, independent of baseline RV function. The degree of RV and LV recovery was dependent on the severity of baseline RV dysfunction.

The effect of hypertension on aortic pulse wave velocity in type-1 diabetes mellitus patients: assessment with MRI

To investigate in type-1 diabetes mellitus (DM1) patients the role of hypertension and of DM1 itself on aortic stiffness by using magnetic resonance imaging (MRI). Consecutive patients from the diabetes and hypertension outpatient clinic and healthy volunteers were included in our study. Subjects were divided into four groups: 32 healthy volunteers (mean age: 54.5 ± 6.8 years), 20 DM1 patients (mean age: 48.3 ± 5.9 years), 31 hypertensive patients (mean age: 59.9 ± 7.2 years) and 28 patients with both DM1 and hypertension (mean age: 50.1 ± 6.2 years). Aortic stiffness was measured by means of pulse wave velocity (PWV) using velocity-encoded MRI. Analysis of variance (ANOVA), uni- and multivariable regression models and the Bonferroni-test for multiple testing, were used for statistical analyses. Mean aortic PWV was 5.7 ± 1.2 m/s in healthy volunteers, 5.9 ± 1.2 m/s in DM1 patients without hypertension, 7.3 ± 1.2 m/s in hypertensive patients and 7.3 ± 1.3 m/s in patients with both DM1 and hypertension. Compared to healthy control subjects, aortic PWV was significantly higher in patients with hypertension (P < 0.001) and in patients with both DM1 and hypertension (P < 0.001), whereas aortic PWV was not increased in patients having DM1 alone. Furthermore, aortic PWV was significantly higher in DM1 patients with hypertension than in patients with DM1 alone (P = 0.002). These findings remained after adjustment for confounding factors. Hypertension has a predominant contributive effect on aortic stiffness in DM1 patients whereas the direct diabetic effect on aortic stiffness is small.

Quantitative assessment of left ventricular function in humans at 7 T

The purpose of this study was to determine the ability of 7 T cardiac magnetic resonance imaging (MRI) to quantitatively assess left ventricular volumes, mass, and function from cine short-axis series and left ventricular diastolic filling from velocity-encoded MRI in 10 healthy volunteers. As comparative "gold standard," the corresponding measures obtained at 1.5 T were taken. Left ventricular volumes, function, and mass were obtained by manual image segmentation. Trans-mitral flow graphs were obtained from 2D one-directional through-plane velocity-encoded MRI planned at the mitral valve in end-systole. Imaging at 7 T MRI was successful in 80% of the examinations. Assessment of left ventricular volumes, function, and mass at 7 T showed good agreement with 1.5 T (no significant differences between variables describing volumes, function, and mass with intraclass correlation coefficients ranging from 0.77 to 0.96). Trans-mitral stroke volume and the ratio between early and atrial peak filling rate showed strong agreement at both field strengths (no significant differences between stroke volumes and filling ratios with intraclass correlation coefficients 0.92 for stroke volumes and 0.77 for peak filling ratios). In conclusion, this study shows that assessing left ventricular volumes, function, and flow is feasible at 7 T MRI and that standardized MRI protocols provide similar quantitative results when compared with 1.5 T MRI.

Cerebral perfusion and aortic stiffness are independent predictors of white matter brain atrophy in type 1 diabetic patients assessed with magnetic resonance imaging

OBJECTIVE

To identify vascular mechanisms of brain atrophy in type 1 diabetes mellitus (DM) patients by investigating the relationship between brain volumes and cerebral perfusion and aortic stiffness using magnetic resonance imaging (MRI).

RESEARCH DESIGN AND METHODS

Approval from the local institutional review board was obtained, and patients gave informed consent. Fifty-one type 1 DM patients (30 men; mean age 44 ± 11 years; mean DM duration 23 ± 12 years) and 34 age- and sex-matched healthy control subjects were prospectively enrolled. Exclusion criteria comprised hypertension, stroke, aortic disease, and standard MRI contraindications. White matter (WM) and gray matter (GM) brain volumes, total cerebral blood flow (tCBF), total brain perfusion, and aortic pulse wave velocity (PWV) were assessed using MRI. Multivariable linear regression analysis was used for statistics, with covariates age, sex, mean arterial pressure, BMI, smoking, heart rate, DM duration, and HbA(1c).

RESULTS

Both WM and GM brain volumes were decreased in type 1 DM patients compared with control subjects (WM P = 0.04; respective GM P = 0.03). Total brain perfusion was increased in type 1 DM compared with control subjects (β = -0.219, P < 0.05). Total CBF and aortic PWV predicted WM brain volume (β = 0.352, P = 0.024 for tCBF; respective β = -0.458, P = 0.016 for aortic PWV) in type 1 DM. Age was the independent predictor of GM brain volume (β = -0.695, P < 0.001).

CONCLUSIONS

Type 1 DM patients without hypertension showed WM and GM volume loss compared with control subjects concomitant with a relative increased brain perfusion. Total CBF and stiffness of the aorta independently predicted WM brain atrophy in type 1 DM. Only age predicted GM brain atrophy.

Head-to-head comparison of contrast-enhanced magnetic resonance imaging and electroanatomical voltage mapping to assess post-infarct scar characteristics in patients with ventricular tachycardias: real-time image integration and reversed registration

AIMS

Substrate-based ablation of ventricular tachycardia (VT) relies on electroanatomical voltage mapping (EAVM). Integration of scar information from contrast-enhanced magnetic resonance imaging (CE-MRI) with EAVM may provide supplementary information. This study assessed the relation between electrogram voltages and CE-MRI scar characteristics using real-time integration and reversed registration.

METHODS AND RESULTS

Fifteen patients without implantable cardiac defibrillator (14 males, 64 ± 9 years) referred for VT ablation after myocardial infarction underwent CE-MRI. Contours of the CE-MRI were used to create three-dimensional surface meshes of the left ventricle (LV), aortic root, and left main stem (LM). Real-time integration of CE-MRI-derived scar meshes with EAVM of the LV and aortic root was performed using the LM and the CARTO surface registration algorithm. Merging of CE-MRI meshes with EAVM was successful with a registration error of 3.8 ± 0.6 mm. After the procedure, voltage amplitudes of each mapping point were superimposed on the corresponding CE-MRI location using the reversed registration matrix. Infarcts on CE-MRI were categorized by transmurality and signal intensity. Local bipolar and unipolar voltages decreased with increasing scar transmurality and were influenced by scar heterogeneity. Ventricular tachycardia reentry circuit isthmus sites were correlated to CE-MRI scar location. In three patients, VT isthmus sites were located in scar areas not identified by EAVM.

CONCLUSION

Integration of MRI-derived scar maps with EAVM during VT ablation is feasible and accurate. Contrast-enhanced magnetic resonance imaging identifies non-transmural scars and infarct grey zones not detected by EAVM according to the currently used voltage criteria and may provide important supplementary substrate information in selected patients.

Relation of left ventricular twist and global strain with right ventricular dysfunction in patients after operative "correction" of tetralogy of fallot

In patients with corrected tetralogy of Fallot (cToF), left ventricular (LV) dysfunction is closely related to right ventricular (RV) dysfunction, indicating adverse ventricular-ventricular interactions. However, the mechanism that links RV dysfunction to LV dysfunction remains unclear. In this prospective study, 32 patients with cToF and 19 controls were enrolled. With cardiac magnetic resonance imaging, biventricular ejection fractions were assessed. Using 2-dimensional speckle tracking, global and regional RV and LV strains and LV twist were assessed. To detect and characterize ventricular-ventricular interaction, the relation between global and regional RV mechanics and global and regional LV mechanics was assessed. Global RV strain, global LV strain, and LV twist were decreased in patients with cToF. Global RV strain correlated with global LV strain (r = 0.66, p <0.001) and LV twist (r = -0.72, p <0.001), indicating the presence of adverse ventricular-ventricular interaction. Furthermore, close relations were observed between apical RV strain and apical LV strain (r = 0.62, p <0.001) and apical LV rotation (r = -0.67, p <0.001). In conclusion, RV strain was significantly related to LV strain and LV twist in patients with cToF and controls. Furthermore, apical RV strain correlated with apical LV strain and apical LV rotation, indicating adverse apical ventricular-ventricular interactions.

Tetralogy of fallot: 3D velocity-encoded MR imaging for evaluation of right ventricular valve flow and diastolic function in patients after correction

PURPOSE

To evaluate three-dimensional (3D) velocity-encoded (VE) magnetic resonance (MR) imaging, as compared with two-dimensional (2D) VE MR imaging, for assessment of pulmonary valve (PV) and tricuspid valve (TV) flow, with planimetry as the reference standard, and to evaluate diastolic function in patients with a corrected tetralogy of Fallot (TOF).

MATERIALS AND METHODS

Local institutional review board approval was obtained, and patients or their parents gave informed consent. Twenty-five patients with a corrected TOF (12 male, 13 female; mean age, 13.1 years +/- 2.7 [standard deviation]; age range, 8-18 years) and 19 control subjects (12 male, seven female; mean age, 14.1 years +/- 2.4; age range, 8-18 years) underwent planimetric MR imaging, 2D VE MR imaging, and 3D VE MR imaging for TV and PV flow evaluation. For evaluation of diastolic function, PV and TV flow were summated. Data were analyzed by using linear regression analysis, paired and unpaired t testing, and Bland-Altman plots.

RESULTS

Strong correlations between the 2D VE MR and 3D VE MR measurements of PV flow (for forward flow: r = 0.87, P < .01; for backward flow: r = 0.97, P < .01) were observed. With PV effective flow as a reference, 3D TV effective flow measurements were more accurate than 2D TV effective flow measurements: In patients, the mean 2D TV effective flow versus 2D PV effective flow difference was 17.6 mL +/- 11 (P < .001), and the mean 3D TV effective flow versus 3D PV effective flow difference was -1.2 mL +/- 4.7 (P = .22). Diastolic functional impairment in patients could be detected at 3D VE MR imaging diastolic assessment.

CONCLUSION

Three-dimensional VE MR imaging is accurate for PV flow assessment and is more accurate than 2D VE MR imaging for TV flow evaluation. Assessment of diastolic function with 3D VE MR imaging can facilitate ongoing research of diastolic dysfunction in patients with a corrected TOF.

Assessment of coronary artery calcium by using volumetric 320-row multi-detector computed tomography: comparison of 0.5 mm with 3.0 mm slice reconstructions

The purpose of this study was to assess the performance of 0.5 versus 3.0 mm slice reconstructions in depicting coronary calcium with special attention to patients having zero calcium scores at 3.0 mm reconstructions by using computed tomography (CT). Imaging was performed by volumetric 320-detector row CT. Scans of 100 patients with a negative and 100 patients with a positive Agatston score at 3.0 mm reconstructions were consecutively selected. Non-overlapping volume sets with 3.0 and 0.5 mm slice thickness were reconstructed from the same raw data and Agatston and volume scores were obtained. The Wilcoxon signed ranks test was used to determine statistical differences between 3.0 and 0.5 mm calcium scores. Agatston and volume scores obtained at 0.5 mm were significantly higher than at 3.0 mm reconstructions (mean Agatston score: 266 +/- 495 vs. 231 +/- 461. Mean volume score: 223 +/- 399 vs. 206 +/- 385, both P < 0.01). In 21% of patients with zero 3.0 mm Agatston scores, a positive Agatston and/or volume score was found at 0.5 mm reconstructions. With volumetric 320-detector row CT, prospective ECG-triggered calcium scoring at 0.5 mm compared to 3.0 mm reconstructions leads to an increase in Agatston and volume scores and small amounts of coronary calcium are earlier depicted. This may be of special interest in patients with zero calcium scores with traditional 3.0 mm measures, where 0.5 mm reconstructions may help in superior depicting or ruling out coronary artery disease.

Scan time and patient dose for thoracic imaging in neonates and small children using axial volumetric 320-detector row CT compared to helical 64-, 32-, and 16- detector row CT acquisitions

BACKGROUND

Recently a 320-detector-row CT (MDCT) scanner has become available that allows axial volumetric scanning of a 16-cm-long range (50 cm field of view) in a single 0.35-s rotation. For imaging neonates and small children, volume scanning is potentially of great advantage as the entire scan range can be acquired in 0.35 s, which can reduce motion artefacts and may reduce the need for sedation in clinical CT imaging. Also, because there is no over-ranging associated with axial volumetric scanning, this may reduce patient radiation dose.

OBJECTIVE

To evaluate, by means of a phantom study, scan time and patient dose for thoracic imaging in neonates and small children by using axial cone-beam and helical fan-beam MDCT acquisitions.

MATERIALS AND METHODS

Paediatric imaging protocols were assessed for a 320-MDCT volumetric scanner (Aquilion ONE, Toshiba, Otawara, Japan). The 320-MDCT scanner allows for cone-beam acquisitions with coverage up to 160 mm, but it also allows for helical fan-beam acquisitions in 64-, 32-, or 16-MDCT modes. The acquisition configurations that were evaluated were 320 x 0.5 mm, 240 x 0.5 mm, and 160 x 0.5 mm for axial volumetric scanning, and 64 x 0.5 mm, 32 x 0.5 mm, and 16 x 0.5 mm for helical scanning. Dose assessment was performed for clinically relevant paediatric angiographic or chest/mediastinum acquisition protocols with tube voltages of 80 or 100 kVp and tube currents between 40 and 80 mA.

RESULTS

Scan time was 0.35 s for 320-MDCT acquisitions, scan times varied between 1.9 s and 8.3 s for helical acquisitions. Dose savings varying between 18% and 40% were achieved with axial volumetric scanning as compared to helical scanning (for 320- versus 64-MDCT at 160 mm and 80 kVp, and for 320- versus 16-MDCT at 80 mm and 100 kVp, respectively). Statistically significant reduction in radiation dose was found for axial 320-MDCT volumetric scanning compared to helical 64-, 32-, and 16-MDCT scanning.

CONCLUSION

Axial thoracic CT of neonates and small children with volumetric 320-MDCT can be performed between 5 and 24 times faster compared to helical scanning and can save patient dose.

Safety of ruling out acute pulmonary embolism by normal computed tomography pulmonary angiography in patients with an indication for computed tomography: systematic review and meta-analysis

INTRODUCTION

Several outcome studies have ruled out acute pulmonary embolism (PE) by normal computed tomography pulmonary angiography (CTPA). We performed a meta-analysis in order to determine the safety of this strategy in a specific group of patients with a strict indication for CTPA, that is, 'likely' or 'high' clinical probability for PE, an elevated D-dimer concentration, or both.

METHODS

Studies that ruled out PE by normal CTPA, with or without subsequent normal bilateral compression ultrasonography (CUS), in patients with a strict indication for CTPA, were searched for in Medline, EMBASE, Web of Science and the Cochrane dataset. The primary endpoint was the occurrence of (fatal) venous thromboembolism (VTE) in a 3-month follow-up period.

RESULTS

Three studies were identified that excluded PE by CTPA alone (2020 patients), and three studies that performed additional CUS of the legs after normal CTPA (1069 patients). The pooled incidence of VTE at 3 months was 1.2% [95% confidence interval (CI) 0.8-1.8] based on a normal CTPA result as a sole test, and 1.1% (95% CI 0.6-2.0) based on normal CTPA and negative CUS findings, resulting in negative predictive values of 98.8% (95% CI 98.2-99.2) and 98.9% (95% CI 98.0-99.4), respectively. This compares favorably with the VTE failure rate after normal pulmonary angiography (1.7%, 95% CI 1.0-2.7). The risk of fatal PE did not differ between the diagnostic strategies (0.6% vs. 0.5%).

CONCLUSION

A normal CTPA result alone can safely exclude PE in all patients in whom CTPA is required to rule out this disease. There is no need for additional ultrasonography to rule out VTE in these patients.

Differences in atherosclerotic plaque burden and morphology between type 1 and 2 diabetes as assessed by multislice computed tomography

OBJECTIVE It is unclear whether the coronary atherosclerotic plaque burden is similar in patients with type 1 and type 2 diabetes. By using multislice computed tomography (MSCT), the presence, degree, and morphology of coronary artery disease (CAD) in patients with type 1 and type 2 diabetes were compared. RESEARCH DESIGN AND METHODS Prospectively, coronary artery calcium (CAC) scoring and MSCT coronary angiography were performed in 135 asymptomatic patients (65 patients with type 1 diabetes and 70 patients with type 2 diabetes). The presence and extent of coronary atherosclerosis as well as plaque phenotype were assessed and compared between groups. RESULTS No difference was observed in average CAC score (217 +/- 530 vs. 174 +/- 361) or in the prevalence of coronary atherosclerosis (65% vs. 71%) in patients with type 1 and type 2 diabetes. However, the prevalence of obstructive atherosclerosis was higher in patients with type 2 diabetes (n = 24; 34%) compared with that in patients with type 1 diabetes (n = 11; 17%) (P = 0.02). In addition, a higher mean number of atherosclerotic and obstructive plaques was observed in patients with type 2 diabetes. In addition, the percentage of noncalcified plaques was higher in patients with type 2 (66%) versus type 1 diabetes (27%) (P < 0.001), resulting in a higher plaque burden for each CAC score compared with that in type 1 diabetic patients. CONCLUSIONS Although CAC scores and the prevalence of coronary atherosclerosis were similar between patients with type 1 and type 2 diabetes, CAD was more extensive in the latter. Also, a relatively higher proportion of noncalcified plaques was observed in patients with type 2 diabetes. These observations may be valuable in the development of targeted management strategies adapted to diabetes type.

Dose and perceived image quality in chest radiography

Chest radiography is the most commonly performed diagnostic X-ray examination. The radiation dose to the patient for this examination is relatively low but because of its frequent use, the contribution to the collective dose is considerable. Consequently, optimization of dose and image quality offers a challenging area of research. In this article studies on dose reduction, different detector technologies, optimization of image acquisition and new technical developments in image acquisition and post processing will be reviewed. Studies indicate that dose reduction in PA chest images to at least 50% of commonly applied dose levels does not affect diagnosis in the lung fields; however, dose reduction in the mediastinum, upper abdomen and retrocardiac areas appears to directly deteriorate diagnosis. In addition to patient dose, also the design of the various digital detectors seems to have an effect on image quality. With respect to image acquisition, studies showed that using a lower tube voltage improves visibility of anatomical structures and lesions in digital chest radiographs but also increases the disturbing appearance of ribs. New techniques that are currently being evaluated are dual energy, tomosynthesis, temporal subtraction and rib suppression. These technologies may improve diagnostic chest X-ray further. They may for example reduce the negative influence of over projection of ribs, referred to as anatomic noise. In chest X-ray this type of noise may be the dominating factor in the detection of nodules. In conclusion, optimization and new developments will enlarge the value of chest X-ray as a mainstay in the diagnosis of chest diseases.

Intracranial hypertension in 2 children with marfan syndrome

Two unrelated children with Marfan syndrome presented with recurrent intracranial hypertension. Both children complained of headache, nausea, and vomiting and one of them had papilledema. Both had increased cerebrospinal fluid pressure, and their complaints disappeared after lumbar puncture. Although severe headache has been reported in Marfan syndrome due to intracranial hypotension, this is to our knowledge the first report of intracranial hypertension in Marfan patients.

A technique for simulating the effect of dose reduction on image quality in digital chest radiography

PURPOSE

The purpose of this study is to provide a pragmatic tool for studying the relationship between dose and image quality in clinical chest images. To achieve this, we developed a technique for simulating the effect of dose reduction on image quality of digital chest images.

MATERIALS AND METHODS

The technique was developed for a digital charge-coupled-device (CCD) chest unit with slot-scan acquisition. Raw pixel values were scaled to a lower dose level, and a random number representing noise to each specific pixel value was added. After adding noise, raw images were post processed in the standard way. Validation was performed by comparing pixel standard deviation, as a measure of noise, in simulated images with images acquired at actual lower doses. To achieve this, a uniform test object and an anthropomorphic phantom were used. Additionally, noise power spectra of simulated and actual images were compared. Also, detectability of simulated lesions was investigated using a model observer.

RESULTS

The mean difference in noise values between simulated and real lower-dose phantom images was smaller than 5% for relevant clinical settings. Noise power spectra appeared to be comparable on average but simulated images showed slightly higher noise levels for higher spatial frequencies and slightly lower noise levels for lower spatial frequencies. Comparable detection performance was shown in simulated and actual images with slightly worse detectability for simulated lower dose images.

CONCLUSION

We have developed and validated a method for simulating dose reduction. Our method seems an acceptable pragmatic tool for studying the relationship between dose and image quality.

Artifacts in ECG-Synchronized MDCT Coronary Angiography

OBJECTIVE

In MDCT coronary angiography, image artifacts are the major cause of false-positive and false-negative interpretations regarding the presence of coronary artery stenoses. Hence, it is important that observers reporting these investigations are aware of the potential presence of image artifacts and that these artifacts are recognized.

CONCLUSION

The article explores the technical causes for various artifacts in MDCT coronary angiography imaging and clinical examples are given.

Treatment of Vertebral Tumor with Posterior Wall Defect Using Image-guided Radiofrequency Ablation Combined with Vertebroplasty: Preliminary Results in 12 Patients

PURPOSE

To evaluate the safety and clinical benefit of vertebral tumor treatment by combined radiofrequency ablation (RFA) and vertebroplasty, for pain reduction in patients who are unable to benefit from noninvasive treatment methods.

MATERIALS AND METHODS

Twelve patients with painful vertebral tumors with posterior wall defect, in whom medical treatment together with radiation therapy and/or chemotherapy had failed, were treated with RFA combined with vertebroplasty. Procedures were performed using multislice CT-fluoroscopy and lateral C-arm fluoroscopic guidance. All patients had posterior wall defects of the vertebra being treated. Ten had lytic posterior wall destruction and two had posterior wall fracture. The visual analog scale (VAS) pain score was measured before, one week after, and three months after treatment. VAS patient satisfaction score was measured before and one week after treatment. The VAS score range was 0-20. The analgesic use was evaluated before and four weeks after treatment and complications were monitored.

RESULTS

Combined RFA and vertebroplasty treatment was technically successful in all patients. Pain significantly decreased after treatment: the mean VAS pain score before treatment was 17.33 +/- 2.46 (range, 13-20) versus 9.25 +/- 4.81 (range, 2-18) one week after treatment (P < .001) and was 7.00 +/- 5.26 (range, 1-14) three months after treatment (P = .020). The mean VAS satisfaction score of all patients was 15.83 +/- 4.26 (range, 4-20). Analgesic use decreased after treatment. No serious treatment related complications occurred.

CONCLUSION

RFA in combination with vertebroplasty for treating vertebral tumors with posterior wall defect appeared safe, and reduced pain substantially in patients who did not benefit from other noninvasive treatment methods.

Imaging techniques in cardiac resynchronization therapy

Cardiac resynchronization therapy is a high cost therapeutic option with proven efficacy on improving symptoms of ventricular failure and for reducing both hospitalization and mortality. However, a significant number of patients do not respond to cardiac resynchronization therapy that is due to various reasons. Identification of the optimal pacing site is crucial to obtain the best therapeutic result that necessitates careful patient selection. Currently, using echocardiography for mechanical dyssynchrony assessment performs patient selection. Multi-Detector-Row Computed Tomography (MDCT) and Magnetic Resonance Imaging (MRI) are new imaging techniques that may assist the cardiologist in patient selection. These new imaging techniques have the potential to improve the success rate of cardiac resynchronization therapy, due to pre-interventional evaluation of the venous coronary anatomy, to evaluation of the presence of scar tissue, and to improved evaluation of mechanical dyssynchrony. In conclusion, clinical issues associated with heart failure in potential candidates for cardiac resynchronization therapy, and the information regarding this therapy that can be provided by the imaging techniques echocardiography, MDCT, and MRI, are reviewed.

Noninvasive assessment of plaque characteristics with multislice computed tomography coronary angiography in symptomatic diabetic patients

OBJECTIVE

Cardiovascular events are high in patients with type 2 diabetes, whereas their risk stratification is more difficult. The higher risk may be related to differences in coronary plaque burden and composition. The purpose of this study was to evaluate whether differences in the extent and composition of coronary plaques in patients with and without diabetes can be observed using multislice computed tomography (MSCT).

RESEARCH DESIGN AND METHODS

MSCT was performed in 215 patients (86 [40%] with type 2 diabetes). The number of diseased coronary segments was determined per patient; each diseased segment was classified as showing obstructive (> or = 50% luminal narrowing) disease or not. In addition, plaque type (noncalcified, mixed, and calcified) was determined. Plaque characteristics were compared in patients with and without diabetes. Regression analysis was performed to assess the correlation between plaque characteristics and diabetes.

RESULTS

Patients with diabetes showed significantly more diseased coronary segments than nondiabetic patients (4.9 +/- 3.5 vs. 3.9 +/- 3.2, P = 0.03) with more nonobstructive (3.7 +/- 3.0 vs. 2.7 +/- 2.4, P = 0.008) plaques. Relatively more noncalcified (28 vs. 19%) and calcified (49 vs. 43%) and less mixed (23 vs. 38%) plaques were observed in patients with diabetes (P < 0.0001). Diabetes correlated with the number of diseased segments and nonobstructive, noncalcified, and calcified plaques.

CONCLUSIONS

Differences in coronary plaque characteristics on MSCT were observed between patients with and without diabetes. Diabetes was associated with higher coronary plaque burden. More noncalcified and calcified plaques and less mixed plaques were observed in diabetic patients. Thus, MSCT may be used to identify differences in coronary plaque burden, which may be useful for risk stratification.

Reduced Aortic Elasticity and Dilatation Are Associated With Aortic Regurgitation and Left Ventricular Hypertrophy in Nonstenotic Bicuspid Aortic Valve Patients

OBJECTIVES

This study sought to assess elasticity and dimensions of the aorta and their impact on aortic valve competence and left ventricular (LV) function in patients with a nonstenotic bicuspid aortic valve (BAV).

BACKGROUND

Intrinsic pathology of the aortic wall is a possible explanation for reduced aortic elasticity and aortic dilatation in patients with BAVs, even in the absence of a stenotic aortic valve. The relationship between aortic wall elasticity, aortic dimensions, aortic valve competence, and LV function in patients with BAVs has not previously been studied with magnetic resonance imaging.

METHODS

Magnetic resonance imaging was performed in 20 patients with nonstenotic BAVs (mean +/- SD, age 27 +/- 11 years) and 20 matched control patients.

RESULTS

The BAV patients showed reduced aortic elasticity as indicated by increased pulse wave velocity in the aortic arch and descending aorta (5.6 +/- 1.3 m/s vs. 4.5 +/- 1.1 m/s, p = 0.01; and 5.2 +/- 1.8 m/s vs. 4.3 +/- 0.9 m/s, p = 0.03, respectively), and reduced aortic root distensibility (3.1 +/- 1.2 x 10(-3) mm Hg(-1) vs. 5.6 +/- 3.2 x 10(-3) mm Hg(-1), p < 0.01). In addition, BAV patients showed aortic root dilatation as compared with control patients (mean difference 3.6 to 4.2 mm, p < or = 0.04 at all 4 predefined levels). Minor degrees of aortic regurgitation (AR) were present in 11 patients (AR fraction 6 +/- 8% vs. 1 +/- 1%, p < 0.01). The LV ejection fraction was normal (55 +/- 8% vs. 56 +/- 6%, p = 0.61), whereas LV mass was significantly increased in patients (54 +/- 12 g/m2 vs. 46 +/- 12 g/m2, p = 0.04). Dilatation at the level of the aortic annulus (r = 0.45, p = 0.044) and reduced aortic root distensibility (r = 0.37, p = 0.041) correlated with AR fraction. Increased pulse wave velocity in the aortic arch correlated with increased LV mass (r = 0.42, p = 0.041).

CONCLUSIONS

Reduced aortic elasticity and aortic root dilatation were frequently present in patients with nonstenotic BAVs. In addition, reduced aortic wall elasticity was associated with severity of AR and LV hypertrophy.