Cardiac MRI: A Useful Tool for Differentiating Cardiac Thrombi from Tumors.

BACKGROUND: Correct diagnosis of cardiac masses is a challenge in clinical practice. Accurate identification and differentiation between cardiac thrombi and tumors is crucial because prognosis and appropriate clinical management vary substantially. OBJECTIVES: To evaluate the diagnostic performances of cardiac magnetic resonance imaging (CMR) in differentiating between cardiac thrombi and tumors. METHODS: A retrospective review of a prospectively maintained database of all CMR scans was performed to distinguish between cardiac thrombi and tumors during a 10 year period in a single academic referral center (2004-2013). Cases with an available standard of reference for a definite diagnosis were included. Correlation of CMR differentiation between thrombi and tumors with an available standard of reference was performed. Sensitivity, specificity, negative predictive value (NPV), positive predictive value (PPV), and accuracy were reported. RESULTS: In this study, 101 consecutive patients underwent CMR for suspicious cardiac masses documented on transthoracic or transesophageal echocardiography. CMR did not detect any cardiac pathology in 17% (17/101), including detection of anatomical variants and benign findings in 18% (15/84). Of the remaining 69 patients, CMR diagnosis was correlated with histopathologic result in 74% (51/69), imaging follow-up in 22% (15/69), and a definite CMR diagnosis (lipoma) in 4% (3/69). For tumors, diagnostic accuracy, sensitivity, specificity, PPV, and NPV were 96.6%, 98%, 86.6%, 96.2%, and 96.6%, respectively. For thrombi, the results were 93.6%, 86.7%, 98.04%, 92.9%, and 97%, respectively. CONCLUSIONS: CMR is highly accurate in differentiating cardiac thrombi from tumors and should be included in the routine evaluation of cardiac masses.

Non-Valvular Findings before Trans-Catheter Aortic Valve Implantation and their Impact on the Procedure.

UNLABELLED: Background: Trans-cathetervalve implantation (TAVI) is a non- surgical alternative for patients with severe aortic stenosis (AS). Pre-procedural computed tomography angiography (CTA) allows accurate "road mapping," aortic annulus sizing and the detection of incidental findings. OBJECTIVES: To document the prevalence of non-valvular extracardiac findings on CTA prior to TAVI and the impact of these findings on the procedure. METHODS: Ninety AS patients underwent CTA as part of pre-TAVI planning. Scans extended from the clavicles to the groin. Non-vascular non-valvular findings were documented and graded as follows: (A) significant findings causing TAVI cancellation or postponement, (B) significant findings leading to a change in the TAVI procedure approach, (C) non-significant findings not affecting the TAVI procedure. RESULTS: TAVI was planned for 90 patients; their average age was 80.2 ± 7.5 years, 53% were females. Overall, non-valvular cardiac, extracardiac and extravascular significant and non-significant incidental findings were documented in 97% of scans (87/90). Significant pathologies causing TAVI cancellation or postponement (category A) were documented in 8%. Significant findings affecting the TAVI procedure (category B) were found in 16% of patients. CONCLUSIONS: Pre-TAVI CTA detected non-valvular extravascular pathologies leading to procedure cancellation/postponement or procedure modification in 8% and 16%, respectively. Comprehensive CTA evaluation that acknowledges the importance of such findings is of major importance since it might alter the TAVI procedure or even render it inappropriate.

The role of cardiac computed tomography in infants with congenital heart disease.

BACKGROUND: Patients with complex congenital heart disease (CHD) have a high incidence of extracardiac vascular and non-vascular malformations. Those additional abnormalities may have an impact on the precise planning of surgical or non-surgical treatment. OBJECTIVES: To assess the role of electrocardiography-gated CT-angiography (ECG-CTA) in the routine evaluation of CHD in neonates and infants particularly for the assessment of extracardiac findings. METHODS: The study cohort comprised 40 consecutive patients who underwent trans-thoracic echocardiography (TTE) and ECG-CTA. TTE and ECG-gated CTA findings regarding extracardiac vascular structures, coronary arteries and airways were compared with surgical or cardiac catheterization findings. Scans were evaluated for image quality using a subjective visual scale (from 1 to 4). Effective radiation dose was calculated for each scan. RESULTS: Median age was 28 +/- 88 days and mean weight 3.7 +/- 1.5 kg. Diagnostic quality was good or excellent (visual image score 3-4) in 39 of 40 scans (97.5%). ECG-CTA provided important additional information on extracardiac vascular structures and airway anatomy, complementing TTE in 75.6% of scans. Overall sensitivity of ECG-gated CTA for detecting extracardiac findings as compared with operative and cardiac catheterization findings was 97.6%. The calculated mean effective radiation dose was 1.4 +/- 0.07 mSv (range 1.014-2.3 mSv). CONCLUSIONS: ECG-CTA is an accurate modality for demonstrating extracardiac structures in complex CHD. It provides important complementary information to TTE with regard to extracardiac vascular structures and coronary artery anatomy. This modality may obviate the need for invasive cardiac catheterization, thus exposing the patient to a much lower radiation dose.

Fetal liver T2* values: defining a standardized scale.

PURPOSE: To define the normal T2* values of liver in the third trimester of pregnancy in normal fetuses. MATERIALS AND METHODS: Multi-echo gradient echo T2* sequence was applied to the fetal abdomen in the axial plane in women undergoing a fetal MRI (1.5 Tesla [T], MRI system). A region of interest, best visualizing in the liver parenchyma was used for measurements. Studies were independently read by two experienced readers to assess intra- and interobserver variability. RESULTS: The study cohort included 46 pregnant women undergoing fetal MRI for any indication other than liver pathology evaluation. Three scans were excluded due to fetal motion. Average maternal and gestational age were 33 ± 4 years and 31.9 ± 3 weeks, respectively. Average T2* values were found to be 19.7 ± 7.4 ms. The intra- and interobserver agreement were very good: 0.93 and 0.8-0.084, respectively. CONCLUSION: T2* MRI allows noninvasive evaluation liver iron content in the third trimester fetus. Measured values at this stage of pregnancy are significantly lower compared with values cited in the literature for adults. This is of major importance in the correct diagnosis of fetal iron overload states. We propose this as the standard reference when evaluating fetal iron overload pathology.

Dobutamine stress MRI for the assessment of coronary artery disease: initial clinical experience in Israel.

BACKGROUND: Over the past few years dobutamine stress magnetic resonance (DSMR) has proven its efficacy as an integral part of the diagnosis of coronary artery disease (CAD). OBJECTIVES: To present the feasibility and safety of DSMR in Israel. METHODS: Thirty patients with suspected or known CAD were studied. DSMR images were acquired during short breath-holds in three short axis views and four-, two-, and three-chamber views. Patients were examined at rest and during a standard dobutamine-atropine protocol. Regional wall motion was assessed in a 16-segment model and the image quality was evaluated using a four-point scale for the visibility of the endocardial border. RESULTS: In 28 patients (93.4%) DSMR was successfully performed and completed within an average of 55 +/- 6 minutes. One patient could not be examined because of claustrophobia and another patient, who was on beta-blockers, did not reach the target heart rate. Image quality was excellent and there was no difference between the rest and stress images in short axis (3.91 +/- 0.29 vs. 3.88 +/- 0.34, P = 0.13, respectively) and long axis (3.83 +/- 0.38 vs. 3.70 +/- 0.49, P = 0.09, respectively) views. Segmental intra-observer agreement for wall motion contractility at rest and stress cine images was almost perfect (K = 0.88, 95% confidence interval = 0.93-0.84, and K = 0.82, 95% CI = 0.88-0.76) respectively. No serious side effects were observed during DSMR. CONCLUSION: The present study confirms the feasibility, safety and excellent image quality of DSMR for the diagnosis of coronary artery diseases.

Prospectively gated coronary computed tomography angiography: uncompromised quality with markedly reduced radiation exposure in acute chest pain evaluation.

BACKGROUND: Coronary computed tomography angiography (CCTA) is an established modality for ruling out coronary artery disease. However, it has been suggested that CCTA may be a source of non-negligible radiation exposure. OBJECTIVES: To evaluate the potential degradation in coronary image quality when using prospective gated (PG) CCTA as compared with retrospective gated (RG) CCTA in chest pain evaluation. METHODS: The study cohort comprised 216 patients: 108 consecutive patients in the PG CCTA arm and 108 patients matched for age, gender and heart rate in the RG CCTA arm. Scans were performed using a 64-slice multidetector CT scanner. All 15 coronary segments were evaluated subjectively for image quality using a 5-point visual scale. Dose-length product was recorded for each patient and the effective radiation dose was calculated RESULTS: The PG CCTA technique demonstrated a significantly higher incidence of step artifacts in the middle and distal right coronary artery, the distal left anterior descending artery, the second diagonal, the distal left circumflex artery, and the second marginal branches. Nevertheless, the diagnostic performance of these scans was not adversely affected. The mean effective radiation doses were 3.8 +/- 0.9 mSv vs.17.2 +/- 3 mSv for PG CCTA and RG CCTA, respectively (P < 0.0001). CONCLUSIONS: Artifacts caused by the PG CCTA technique (64 MDCT) scanners tended to appear in specific coronary segments but did not impair the overall diagnostic quality of CCTA and there was a marked reduction in radiation exposure. We conclude that 64-slice PG CCTA is suitable for clinical use, especially for acute chest pain "fast track" evaluation targeted at relatively young subjects in a chest pain unit.

Pulmonary Computed Tomography Parenchymal and Vascular Features Diagnostic of Postablation Pulmonary Vein Stenosis.

PURPOSE: The purpose of this study was to define the full spectrum of pulmonary computed tomography (CT) changes characteristic of postablation pulmonary vein stenosis (PVS). MATERIALS AND METHODS: We retrospectively reviewed our pulmonary vein isolation database. PVS was graded as follows: grade 1:<50%, grade 2: 50% to 75%, grade 3: 76% to 99%, and grade 4: total occlusion. CT parenchymal and vascular changes were detected and correlated with clinical course and nuclear scans. RESULTS: Of 486 patients who underwent pulmonary vein isolation, 56 patients (11%) were symptomatic, prompting referral to CT evaluation. Grades 1, 2, 3, and 4 PVS were documented in 42, 1, 2, and 11 patients, respectively. Apart from PVS, abnormal CT findings were present only in patients with PVS grades 2 to 4. Pulmonary parenchymal changes (consolidation, "ground glass" opacities, interlobular septal thickening, and volume loss) were found in PVS grades 2 to 4. Pulmonary vascular changes (oligemia, "sluggish flow," and collateral mediastinal vessels) were shown in patients with grades 3 to 4 PVS. Concomitant nuclear scans documented reduced lung perfusion. All findings were located to the lobe drained by the affected vein. Complete resolution of pulmonary findings on follow-up CT scans was demonstrated in 20% of patients. Eleven stents were inserted in 7 patients with PVS grades 2 to 4, none of which demonstrated radiologic or clinical resolution. CONCLUSIONS: A typical CT complex of both parenchymal and vascular findings in the affected lobe is diagnostic of postablation PVS. Lack of clinical and radiologic resolution in most patients, even after stent insertion, further highlights the importance of early recognition of this underdiagnosed condition.

Acute myocarditis: noninvasive evaluation with cardiac MRI and transthoracic echocardiography.

OBJECTIVE: The diagnosis of acute myocarditis is challenging. Nonspecific clinical presentation and an overlap with the diagnosis of acute myocardial infarction present a diagnostic dilemma. The purpose of this article is to describe the role of cardiac MRI and transthoracic echocardiography (TTE) in the diagnosis of acute myocarditis. MATERIALS AND METHODS: Thirty-two sequential patients (all male; average age, 33 years) with clinically suspected myocarditis were included. All patients underwent cardiac MRI with sequences dedicated for the evaluation of myocardial delayed enhancement and TTE for the evaluation of wall motion abnormalities (WMAs). Nine patients were excluded because of diagnosis of acute myocardial infarction (n=2) or inadequate cardiac MRI technique (n=7). Retrospective analysis of the images of the remaining 23 patients was performed. RESULTS: An epicardial pattern of abnormal patchy myocardial delayed enhancement was seen on cardiac MRI in 21 of 23 (91%) patients. WMAs were seen on TTE in eight of 23 (35%) patients. Regional rather than global involvement was seen mainly in the inferolateral segments, with a predominance in the midventricular portion. CONCLUSION: Cardiac MRI might have a greater impact than TTE in confirming the presence of acute myocarditis and evaluating the extent of myocardial involvement. Cardiac MRI provides noninvasive imaging that may obviate invasive procedures such as coronary catheter angiography or endomyocardial biopsy.

The role of ECG-gated MDCT in the evaluation of aortic and mitral mechanical valves: initial experience.

OBJECTIVE: The objective of our study was to evaluate the role of ECG-gated MDCT in the functional evaluation of mechanical prosthetic aortic and mitral valves. MATERIALS AND METHODS: Twenty sequential patients with 23 mechanical prosthetic valves were evaluated with an ECG-gated 40- or 64-MDCT scanner. Multiplanar reformation, maximal-intensity-projection, volume-rendering, and volume-averaging techniques were used for visualization of valve leaflets in systole and diastole. The visibility of each mechanical valve was evaluated by consensus of a radiologist and a cardiologist using a subjective 5-point scale (0-4). MDCT findings were correlated with fluoroscopic opening and closing angle measurements and echocardiographic pressure gradient measurements in 11 and 19 valves, respectively. RESULTS: The series included 18 bileaflet and five single-leaflet mechanical valves. The visibility score for the bileaflet mechanical valves was excellent (score of 4) in all 18 cases, but it was lower for single-leaflet valves (mean score, 2.8; range, 1-4) (p = 0.04). Bland-Altman plots showed high agreement between MDCT and fluoroscopy for measurements of opening and closing angles of bileaflet mechanical valves. In four patients, a stuck valve was seen on MDCT and was confirmed by fluoroscopy. Doppler echocardiography showed increased transvalvular pressure in two of the four patients with a stuck mitral valve and increased transaortic pressure in four patients with normal prosthetic aortic valve motion. CONCLUSION: Our preliminary results suggest that MDCT is a promising technique for functional evaluation of bileaflet mechanical valves, allowing reliable measurements of opening and closing leaflet angles. However, the role of MDCT in the evaluation of single-leaflet valves might be limited.

Myocardial bridging, a common anatomical variant rather than a congenital anomaly.

The recent introduction of coronary computed tomographic angiography into clinical use as a noninvasive tool for coronary artery evaluation has evoked a new interest in myocardial bridging. Recent studies using multidetector computed tomography for the evaluation of coronary anatomy have shown myocardial bridging to be more prevalent than previously reported in angiographic series. The purpose of this article was to provide an overview of the current knowledge on the prevalence and features of myocardial bridging as shown by multidetector computed tomography and to discuss the potential clinical implications of this entity.

Extra-cardiac findings on coronary computed tomography scanning.

BACKGROUND: Cardiac computed tomography scans include several extra-cardiac structures such as mediastinum, lung parenchyma and upper abdominal organs. A variety of abnormalities in those structures might be clinically important and in some cases might explain the patient's complaints. OBJECTIVES: To analyze consecutive CCT examinations for the prevalence and clinical significance of extra-cardiac findings. METHODS: Cardiac CT scans of 134 sequential patients (104 males, 30 females) aged 20-77 (mean 54 years) with suspected coronary artery disease were prospectively and independently reviewed by a consensus of two radiologists for the presence of lung, mediastinal, pleural, upper abdominal and skeletal abnormalities. CT scans with extra-cardiac abnormalities were divided into two groups: group A- defined as "clinically significant" or "potentially significant findings" - consisted of patients requiring further evaluation or follow-up, and group B - "clinically non-significant findings." RESULTS: Extra-cardiac abnormalities were found in 103 of the 134 patients (76.8%). Group A abnormalities were found in 52/134 patients (39%), while group B abnormalities were seen in 85/134 (63%). The most common abnormalities in group A were non-calcified lung nodules (> 4 mm) noted in 17/134 patients (13%), followed by enlarged mediastinal lymph nodes (> 10 mm) in 14/134 (10%), diaphragmatic hernia (2 cm) in 12/134 (9%), moderate or severe degenerative spine disease in 12/134 (9%), and emphysema and aortic aneurysm in 6 patients each (4.5%). A malignant lung tumor was noted in one patient. CONCLUSIONS: There is a high prevalence of non-cardiac abnormalities in patients undergoing CCT. Clinically significant or potentially significant findings can be expected in 40% of patients who undergo CCT, and these will require further evaluation and follow-up. The reporting radiologist should be experienced in chest imaging.

Printed MDCT 3D models for prediction of left atrial appendage (LAA) occluder device size: a feasibility study.

AIMS: Transoesophageal echocardiography (TEE) and multidetector computed tomography (MDCT) currently serve as imaging modalities for left atrial appendage (LAA) occlusion preprocedural planning. We assessed the feasibility of MDCT-based models to predict the correct size of device for LAA occlusion procedures. METHODS AND RESULTS: Patients planned for LAA occlusion underwent MDCT before implantation, which was used for creating and printing 3D LAA models. Three cardiologists evaluated the 3D models and predicted the correct size of the device by manual manipulation. These predictions were compared with the actual device implanted during the procedure. Twenty-nine patients were included in this study. AMPLATZER and WATCHMAN devices were deployed in 12 and 17 patients, respectively. Two procedures were aborted due to failure of occlusion; all three physicians predicted it. There was good correlation between the 3D models and the inserted device for AMPLATZER devices with a concordance correlation coefficient of 0.778 (p=0.001) and poor agreement for WATCHMAN devices - concordance correlation coefficient of 0.315 (p=0.203). Agreement among the three physicians for AMPLATZER and WATCHMAN devices was excellent, with a calculated average intra-class correlation of 0.915 and 0.816, respectively. CONCLUSIONS: We found LAA printed 3D models to be accurate for prediction of LAA occluder device size for the AMPLATZER device but not for the WATCHMAN device.

Cardiac CT Angiography (CCTA) predicts left atrial appendage occluder device size and procedure outcome.

AIM: To investigate the role of cardiac CT angiography (CCTA) in predicting optimal left atrial appendage (LAA) occluder size and procedure outcome. METHODS AND RESULTS: Thirty-six patients underwent pre-procedural CCTA. CCTA and TEE LAA orifice diameters and perimeters were compared with the implanted device size. CCTA 3D configuration was correlated with procedure outcome. Watchman™ device (N = 18): diameters were 21 ± 4, 26 ± 5 and 25 ± 3 mm for TEE, CCTA and inserted device, respectively. Average perimeters were 61 ± 10, 74 ± 8 and 78 ± 11 mm for TEE, CCTA and inserted device, respectively. Better agreement with the device size was found for CCTA compared to TEE (Bland-Altman). ACP™ device (N = 15): diameters were 20 ± 5, 25 ± 4 and 23 ± 4 for TEE, CCTA and inserted device, respectively. Average perimeters were 58 ± 11, 72 ± 15 and 72 ± 13 mm for TEE, CCTA and inserted device, respectively. Excellent correlation and agreement with the device size was found for CCTA compared to TEE. CCTA perimeter >100 mm and "cactus" 3D configuration had a specificity of 96 and 81% respectively for procedure failure. CONCLUSIONS: CCTA LAA ostial perimeter predicted better the optimal occluder size as compared with the currently used LAA TEE diameter. Moreover, CCTA 3D data may help in predicting potential complications.

Left ventricular apical ballooning: not an uncommon variant of acute myocardial infarction in women.

BACKGROUND: Left ventricular apical ballooning, a new syndrome recently described in Japan, is characterized by chest pain, electrocardiographic changes mimicking acute myocardial infarction, and transient apical dyskinesia with normal coronary arteries. Although several studies have defined the clinical characteristics, the prevalence of this syndrome remains unclear. HYPOTHESIS: This study sought to determine the prevalence of left ventricular apical ballooning syndrome. METHODS: From January 2002 to September 2004, clinical, echocardiographic, and angiographic data of hospitalization and follow-up were collected from 638 consecutive patients referred to our Heart Institute for primary percutaneous intervention. RESULTS: Thirteen patients (2%) were diagnosed with transient left ventricular apical ballooning. All but one patient were women, representing a 6% incidence for the female patients with acute myocardial infarction. A triggering factor was identified in eight. One patient died of cardiogenic shock. Left ventricular systolic function recovered completely within 4-5 weeks in the remaining 12 survivors. CONCLUSION: This syndrome is not uncommon and should be considered particularly in female patients presenting with acute myocardial infarction.

Primary angioplasty with routine stenting compared with thrombolytic therapy in elderly patients with acute myocardial infarction.

BACKGROUND: Prior studies have yielded conflicting data on the advantage of primary angioplasty compared with thrombolysis in elderly patients with acute myocardial infarction (AMI). These studies, however, were performed before the contemporary widespread use of intracoronary stents and glycoprotien IIb/IIIa antagonists. METHODS: We prospectively compared the outcome of 130 consecutive elderly patients (aged > or =70 years) with ST-elevation AMI who were admitted to 2 similar neighboring medical centers. Patients were assigned to receive either thrombolytic therapy with accelerated tissue-type plasminogen activator (center I) or primary angioplasty with routine stenting (center II). RESULTS: Of the patients assigned to receive primary angioplasty, 91% underwent stenting. At 6 months, patients treated with primary angioplasty, compared with those treated with thrombolytic therapy, had a lower incidence of reinfarction (2% vs 14%, P =.053) and revascularization for recurrent ischemia (9% vs 61%, P <.001) and a significant reduction in the prespecified combined end point of death, reinfarction, or revascularization for recurrent ischemia (29% vs 93%, P <.01). Primary angioplasty remained an independent predictor of the triple combined end point after controlling for potential covariables (relative risk 0.63, 95% CI 0.38-0.84). Major bleeding complications were also significantly reduced in the primary angioplasty group (0% vs 17%, P =.03). CONCLUSIONS: Compared with thrombolysis, primary angioplasty with routine stenting in elderly patients with AMI is associated with better clinical outcomes and a lower risk of bleeding complications.

Association of left ventricular filling parameters assessed by pulsed wave Doppler and color M-mode Doppler echocardiography with left ventricular pathology, pulmonary congestion, and left ventricular end-diastolic pressure.

Among 90 consecutive patients with various degrees of left ventricular (LV) dysfunction (normal patients, LV hypertrophy, LV ejection fraction <50%, and <30%), the mitral valve pulse-wave E/A ratio showed a characteristic U-shaped curve with increasing severity of LV dysfunction. In contrast, there was a significant progressive decrease in flow propagation velocity of the E-wave (Vp) and a significant increase in E/Vp values with increasing severity of LV dysfunction. The E/Vp ratio was the best predictor of pulmonary congestion, and in a subgroup of patients who underwent cardiac catheterization, it was the only significant predictor of LV end-diastolic pressure.

Left main coronary artery atresia: extremely rare coronary anomaly in an asymptomatic adult and an adolescent soccer player.

Left main coronary artery atresia is a very rare coronary anomaly with only 33 cases reported in the literature, of whom only 1 patient is asymptomatic. Pediatric patients are usually very symptomatic early in life (dyspnea, syncope, failure to thrive, ventricular tachycardia, and sudden death), whereas adult patients begin showing symptoms (angina or sudden death) only at an advanced age. Given the high risk related to the presence of left main coronary artery atresia, and in view of the good results obtained by coronary artery bypass surgery, coronary artery revascularization should always be considered as the possible treatment of choice for establishing adequate myocardial blood flow.

Deformation dynamics and mechanical properties of the aortic annulus by 4-dimensional computed tomography: insights into the functional anatomy of the aortic valve complex and implications for transcatheter aortic valve therapy.

OBJECTIVES: The purpose of this study was to assess deformation dynamics and in vivo mechanical properties of the aortic annulus throughout the cardiac cycle. BACKGROUND: Understanding dynamic aspects of functional aortic valve anatomy is important for beating-heart transcatheter aortic valve implantation. METHODS: Thirty-five patients with aortic stenosis and 11 normal subjects underwent 256-slice computed tomography. The aortic annulus plane was reconstructed in 10% increments over the cardiac cycle. For each phase, minimum diameter, ellipticity index, cross-sectional area (CSA), and perimeter (Perim) were measured. In a subset of 10 patients, Young's elastic module was calculated from the stress-strain relationship of the annulus. RESULTS: In both subjects with normal and with calcified aortic valves, minimum diameter increased in systole (12.3 ± 7.3% and 9.8 ± 3.4%, respectively; p < 0.001), and ellipticity index decreased (12.7 ± 8.8% and 10.3 ± 2.7%, respectively; p < 0.001). The CSA increased by 11.2 ± 5.4% and 6.2 ± 4.8%, respectively (p < 0.001). Perim increase was negligible in patients with calcified valves (0.56 ± 0.85%; p < 0.001) and small even in normal subjects (2.2 ± 2.2%; p = 0.01). Accordingly, relative percentage differences between maximum and minimum values were significantly smallest for Perim compared with all other parameters. Young's modulus was calculated as 22.6 ± 9.2 MPa in patients and 13.8 ± 6.4 MPa in normal subjects. CONCLUSIONS: The aortic annulus, generally elliptic, assumes a more round shape in systole, thus increasing CSA without substantial change in perimeter. Perimeter changes are negligible in patients with calcified valves, because tissue properties allow very little expansion. Aortic annulus perimeter appears therefore ideally suited for accurate sizing in transcatheter aortic valve implantation.

Clinical predictors of stress-induced transient left ventricular dilatation in patients with nonsignificant coronary disease.

Left ventricular transient dilatation (TD) during stress myocardial perfusion imaging has been associated with extensive and severe coronary artery disease (CAD). The authors investigated the clinical predictors of TD in patients with nonsignificant CAD. The authors retrospectively studied 134 consecutive patients with exercise (n=59) or dipyridamole (n=75) stress-induced TD who had undergone coronary angiography within 6 months of the test. Significant CAD was defined as diameter stenosis ≥70% in at least one major coronary artery, and significant left main disease as >50% diameter stenosis. Angiographically-significant CAD was found in 126 patients (94%), and nonsignificant CAD in the remaining 8 patients (6%). No differences in gender, history of smoking, hyperlipidemia, family history of CAD, body mass index, and left ventricular ejection fraction were found between patients with significant and nonsignificant CAD. All 8 nonsignificant CAD patients had a history of either hypertension (7/8) or electrocardiographic criteria for left ventricular hypertrophy (1/8), compared with 58% of the hypertensive patients in the significant CAD group (P=.02). Nonsignificant CAD patients were also characterized by lack of diabetes mellitus (P=.05) or prior myocardial infarction (P=.05). Hypertension seems to be an important clinical predictor of TD in patients with nonsignificant CAD.

The prevalence and anatomical patterns of intramuscular coronary arteries: a coronary computed tomography angiographic study.

OBJECTIVES: This study sought to report prevalence and radiologic patterns of intramuscular coronary arteries (myocardial bridging) on coronary computed tomographic angiography (CCTA). BACKGROUND: Reported prevalence of intramuscular coronary arteries varies between 5% and 86% in autopsy and 0.8% and 4.9% in coronary angiography. Intramuscular coronary arteries can cause technical problems during coronary bypass surgery, including inadvertent perforation of the right ventricle. METHODS: One hundred and eighteen consecutive patients were studied with CCTA using Brilliance 40/64 multidetector computed tomography (Philips Medical Systems, Cleveland, Ohio). Parameters evaluated were number, length, and depth of intramuscular coronary segments; diameter and evidence of atherosclerosis in the involved artery proximal and within the intramuscular segment; and its course in relation to the interventricular septum and right ventricular wall. RESULTS: Forty-seven intramuscular segments were identified in 36 of 118 (30.5%) patients. Most were located in mid left anterior descending coronary artery (LAD), 27 of 47 (57%), and distal LAD, 7 of 47 (15%). The CCTA features in the LAD showed 3 patterns: superficial septal, 10 of 34 (29.4%); deep septal, 14 of 34 (41.1%); and right ventricular type, 10 of 34 (29.4%). Intramuscular segment length ranged from 13 to 40 mm. Coronary diameter proximal and within the affected segment was 2.2 +/- 0.5 mm versus 1.6 +/- 0.6 mm for the LAD, and 1.9 +/- 0.3 mm versus 1.5 +/- 0.6 mm for the remaining arteries, respectively. Depth ranged from 0.1 to 5.6 mm. CONCLUSIONS: Prevalence of intramuscular coronary arteries on CCTA is in concordance with most pathological reports and higher than in angiographic series. The CCTA clearly showed presence, course, and anatomical features of intramuscular coronary arteries. Coronary computed tomographic angiography may provide potentially useful information in the preoperative evaluation of candidates for coronary bypass surgery.