Showing papers on "Cardiac magnetic resonance imaging published in 2007"
TL;DR: Septal myectomy provides consistent resection of the obstructing portion of the anterior basal septum, whereas the effect of ethanol septal ablation is more variable, which may have important implications for patient selection and management as well as long-term outcome.
218 citations
TL;DR: RT3DECHO DS is superior to RT3DechO apical rotation and 2DECHo for right ventricular quantification, and performs acceptably when compared with cardiac magnetic resonance imaging in healthy individuals.
Abstract: Background Assessment of right ventricular function by 2-dimensional echocardiography (2DECHO) is difficult because of its complex shape. Real-time 3-dimensional echocardiography (RT3DECHO) may be superior. Methods End-diastolic volume, end-systolic volume, stroke volume, and ejection fraction obtained by 2DECHO, RT3DECHO short-axis disk summation (DS), and RT3DECHO apical rotation were compared with cardiac magnetic resonance imaging in 71 healthy individuals. Results RT3DECHO DS showed less volume underestimation compared with 2DECHO and RT3DECHO apical rotation. Test-retest variability for RT3DECHO DS end-diastolic volume, end-systolic volume, stroke volume, and ejection fraction were 3.3%, 8.7%, 10%, and 10.3%, respectively. Normal reference ranges of indexed volumes (mean ± 2SD) for right ventricular end-diastolic volume, end-systolic volume, stroke volume, and ejection fraction were 38.6 to 92.2 mL/m 2 , 7.8 to 50.6 mL/m 2 , 22.5 to 42.9 mL/m 2 , and 38.0% to 65.3%, respectively, for women and 47.0 to 100 mL/m 2 , 23.0 to 52.6 mL/m 2 , 14.2 to 48.4 mL/m 2 , and 29.9% to 58.4%, respectively, for men. Conclusions RT3DECHO DS is superior to RT3DECHO apical rotation and 2DECHO for right ventricular quantification, and performs acceptably when compared with cardiac magnetic resonance imaging in healthy individuals.
172 citations
TL;DR: The myocardium at risk of infarction can be determined angiographically as validated in subjects with transmural myocardial infarcts using the Myocardial Jeopardy Index and a modified version of the APPROACH scores.
Abstract: Aims Global angiographic scores have been developed to determine the extent of myocardium jeopardized by significant coronary stenosis. We adapted these scores to quantify the anatomic area at risk during acute myocardial infarction. We used contrast-enhanced magnetic resonance (CMR) infarct imaging to measure the portion of myocardium that developed necrosis within the so defined angiographic area at risk.
Methods and results In 83 subjects presenting for primary percutaneous intervention, the myocardium at risk was estimated angiographically using the Myocardial Jeopardy Index (BARI) and a modified version of the Alberta Provincial Project for Outcome Assessment in Coronary Heart Disease (APPROACH) scores. CMR was performed within a week to measure infarct size, infarct endocardial surface area (infarct-ESA), and infarct transmurality. As infarct transmurality increased, the infarct size closely approximated the myocardium at risk by angiography. In 35 subjects with transmural infarcts, the area at risk by BARI and APPROACH scores matched the infarct size ( r = 0.90 and r = 0.92, P < 0.001). Additionally, BARI and APPROACH scores matched the infarct-ESA in all subjects independently of collateral flow and time to reperfusion ( r = 0.90 and r = 0.87, P < 0.001). The presence of early reperfusion, collaterals, or both was associated with a progressive decrease in infarct transmurality ( P < 0.001 for trend) with no difference in the infarct-ESA.
Conclusion The myocardium at risk of infarction can be determined angiographically as validated in subjects with transmural myocardial infarcts. Salvage provided by early reperfusion or collaterals occurs by limiting infarct transmurality, thereby the extent of endocardial infarct involved also allows estimation of the myocardium at risk in patients presenting with STEMI.
170 citations
TL;DR: Findings support the hypothesis that central sympathetic activation is associated with the development of LVH in human hypertension, and no consistent relationship existed between arterial blood pressure and sympathetic activity or LVM index.
Abstract: Background— Sympathetic activation has been implicated in the development of left ventricular hypertrophy (LVH). However, the relationship between sympathetic activation and LV mass (LVM) has not been clearly defined across a range of arterial pressure measurements. The present study was planned to determine that relationship, using cardiac magnetic resonance imaging to accurately quantify LVM, in hypertensive patients with and without LVH and in normal subjects. Methods and Results— Twenty-four patients with uncomplicated and untreated essential hypertension (LVH[−]) were compared with 25 patients with essential hypertension and left ventricular hypertrophy (LVH[+]) and 24 normal control subjects. Resting muscle sympathetic nerve activity was quantified as multiunit bursts and single units. Cardiac magnetic resonance imaging–determined LVM was indexed to body surface area (LVM index); in the LVH[−] group, LVM index was 67±2.1 g/m2, a value between those of the LVH[+] (91±3.4 g/m2) and normal control (57±...
170 citations
TL;DR: In the studied cohort, there was a linear relation between scar size and ejection fraction and LV volumes independent of scar location and transmurality, and in multivariate analysis, scar size was the strongest independent predictor of ejection fractions and volumes independently of scar localization and transmURality.
Abstract: Studies of patients with acute myocardial infarction (MI) suggest that anterior transmural infarcts are associated with greater left ventricular (LV) remodeling compared with nontransmural nonanterior infarctions. It is unclear whether this relation also exists in long-term survivors of MI. Cardiac magnetic resonance imaging was used to explore the relation between myocardial scar size, localization, transmurality, and degree of long-term LV remodeling in patients with healed MI. Subjects were recruited from a registry of patients with healed MI who participated in the OPTIMAAL trial. Cardiac magnetic resonance imaging was performed to assess LV mass, volumes, LV ejection fraction, and myocardial scarring, adjusting for myocardial ischemia. Fifty-seven patients (mean age 69 ± 10 years mean ejection fraction 49 ± 13%) were studied 4.4 ± 0.4 years after MI. Anterior scar was found in 19 patients and nonanterior scar in 33, whereas 5 patients did not show myocardial scar. Transmural scar was evident in 36 patients. In the 52 patients with scar, average total scar size was 13 ± 8% of total LV mass. There was a strong linear relation between scar size and LV end-diastolic volume index (r = 0.81, p
151 citations
TL;DR: In this paper, the authors report a large-scale study of Takotsubo cardiomyopathy using magnetic resonance imaging (CMR) to show a lack of irreversible damage in the acute setting, thereby reliably predicting recovery.
Abstract: In Takotsubo cardiomyopathy, or transient left ventricular (LV) apical ballooning syndrome, normalization of wall motion can occur after as long as 3 months. We report 1 of the largest series to date outside Japan and emphasize the utility of cardiac magnetic resonance imaging (CMR) to show a lack of irreversible damage in the acute setting, thereby reliably predicting recovery. During the previous 6 years, we saw 22 patients who met the following criteria: (1) a suspected myocardial infarction based on symptoms, an abnormal electrocardiogram, and/or elevated serum cardiac markers; (2) an anteroapical wall motion abnormality; and (3) no significant occlusive epicardial coronary artery disease or observed vasospasm. Ten patients underwent delayed enhancement CMR to assess myocardial viability during the index presentation. All 10 patients had an absence of irreversible damage, as evidenced by lack of gadolinium "hyperenhancement"; later, their LV function returned to normal. Eight other patients, available for outpatient follow-up evaluation, also had normalization of LV function. Takotsubo cardiomyopathy is increasingly being recognized outside Japan and must be distinguished from acute myocardial infarction. In conclusion, CMR is useful to document segmental LV dysfunction and lack of irreversible damage and to predict functional recovery.
104 citations
TL;DR: Based on the data available, it appears that L-T4 replacement should be considered in patients with mild hypothyroidism in presence of associated cardiovascular risk factors in the attempt to reverse these negative prognostic factors and improve the cardiovascular risk.
Abstract: The cardiovascular risk is increased in patients with overt hypothyroidism, and several potential cardiovascular risk factors were similarly reported in patients with subclinical hypothyroidism. Only recently have more data become available about the effects of mild hypothyroidism on the cardiovascular system. An impaired left ventricular diastolic function, which is characterized by slowed myocardial relaxation and impaired ventricular filling, is the most consistent cardiac abnormality in patients with mild thyroid hormone deficiency. Impaired left ventricular diastolic function on effort was also documented by radionuclide ventriculography. Studies performed by ultrasonic myocardial textural analysis suggest an altered myocardial composition in patients with mild hypothyroidism. Moreover, pulsed tissue Doppler analysis revealed that patients with mild hypothyroidism had changes in myocardial time intervals in several left ventricular segments. Finally, alterations in cardiac hemodynamic were documented by cardiac magnetic resonance imaging in presence of mild disease. Vascular function is impaired in patients with mild and subclinical hypothyroidism, as documented by the increase in systemic vascular resistance and arterial stiffness and by the impaired endothelial function. The negative effect induced by mild hypothyroidism on cardiovascular system can be reverted restoring euthyroidism with levothyroxine (L-T4) therapy. Based on the data available, it appears that L-T4 replacement should be considered in patients with mild hypothyroidism in presence of associated cardiovascular risk factors in the attempt to reverse these negative prognostic factors and improve the cardiovascular risk.
99 citations
TL;DR: In patients admitted to hospital with possible AMI, the consideration of both ST-segment elevation and depression in the standard 12 lead-ECG recording significantly increases the sensitivity for the detection of AMI with only a slight decrease in the specificity.
93 citations
TL;DR: Cardiac magnetic resonance imaging is widely recognized as the most accurate noninvasive imaging modality for the assessment of left ventricular (LV) function and may be quite useful for the detection of contractile dyssynchrony.
89 citations
TL;DR: A number of historical and biochemical parameters were looked at in order to determine their relationship to cardiac iron overload and the effect of cardiac iron on functional and structural changes of the heart in transfusion-dependent thalassemics.
Abstract: Recent advances in magnetic resonance imaging (MRI) techniques allow the assessment of iron overload in tissues 1 especially the heart, 2 in transfusion-dependent thalassemia patients. The R2* value (1/T2*) recorded in the intraventricular septum of the heart indirectly measures the degree of cardiac iron load. Applying this new technology we looked at a number of historical and biochemical parameters in order to determine their relationship to cardiac iron overload and the effect of cardiac iron on functional and structural changes of the heart in transfusion-dependent thalassemics.
75 citations
TL;DR: In this paper, the accuracy of MPI obtained by echocardiography to quantify RV function was assessed in 57 adults with repaired tetralogy of fallot and significant chronic pulmonary regurgitation.
Abstract: Adults with repaired tetralogy of Fallot and significant chronic pulmonary regurgitation are at risk for progressive right ventricular (RV) dilatation and dysfunction. The assessment of RV function is important in the management in these patients. There is still a lack of an adequate geometric model to quantify RV function by echocardiography. The myocardial performance index (MPI) is a nonvolumetric method to quantify global ventricular function. In this study, the accuracy of MPI obtained by echocardiography to quantify RV function was assessed in 57 adults with repaired tetralogy of Fallot. The MPI measurement was compared with the RV ejection fraction (EF) derived by cardiac magnetic resonance imaging. There was a negative linear correlation between the MPI and the RVEF (r = 0.73, p or =0.40 had a sensitivity of 81% and a specificity of 85% to diagnose a RVEF or =0.50. In a multivariate regression model, the MPI was not affected by the degree of pulmonary regurgitation, the presence of tricuspid regurgitation, or the QRS duration. In conclusion, the Doppler-derived MPI is a simple and reliable method for the evaluation of RV systolic function in adults with repaired tetralogy of Fallot.
TL;DR: 58 consecutive patients with diverse cardiac disorders and clinical characteristics, referred for clinical MRI studies, who were evaluated by cardiac MRI and 3DTTE show good correlation between the two modalities.
Abstract: Due to reliance upon geometric assumptions and foreshortening issues, the traditionally utilized transthoracic two-dimensional echocardiography (2DTTE) has shown limitations in assessing left ventricular (LV) volume, mass, and function. Cardiac magnetic resonance imaging (MRI) has shown potential in accurately defining these LV characteristics. Recently, the emergence of live/real time three-dimensional (3D) TTE has demonstrated incremental value over 2DTTE and comparable value with MRI in assessing LV parameters. Here we report 58 consecutive patients with diverse cardiac disorders and clinical characteristics, referred for clinical MRI studies, who were evaluated by cardiac MRI and 3DTTE. Our results show good correlation between the two modalities.
TL;DR: The relationship between right-sided cardiac abnormalities and exercise capacity in patients with tetralogy of fallot was investigated in this paper, showing that right ventricular ejection fraction was the only cardiac magnetic resonance imaging predictor of predicted peak oxygen consumption, oxygen consumption at ventilatory anaerobic threshold, and oxygen pulse.
Abstract: Objective exercise testing in patients with repaired tetralogy of Fallot frequently identifies gross deficiencies in exercise capacity. These findings are typically attributed to right ventricular dysfunction, pulmonary valve regurgitation, and pulmonary artery stenosis and are used to justify referrals for surgical or transcatheter interventions. However, the relation between right-sided cardiac abnormalities and exercise capacity in this patient group is poorly understood. Cardiac magnetic resonance imaging correlates of exercise capacity in 37 patients with repaired TOF were retrospectively examined. In conclusion, on multivariate analysis, right ventricular ejection fraction was the only cardiac magnetic resonance imaging predictor of percentage of predicted peak oxygen consumption, oxygen consumption at ventilatory anaerobic threshold, and oxygen pulse.
TL;DR: Cardiac MDCT has a strong potential to detect many qualitative and quantitative abnormalities of the right ventricle in patients with ARVD/C.
Abstract: The purpose of this study was to report 1 center’s experience with multidetector computed tomography (MDCT) in the evaluation of patients suspected to have arrhythmogenic right ventricular (RV) dysplasia/cardiomyopathy (ARVD/C) RV dilatation/dysfunction is 1 of the most important criteria for establishing the diagnosis of ARVD/C Cardiac magnetic resonance imaging (MRI) is the most preferred imaging modality for the diagnosis of ARVD/C However, many patients with suspected ARVD/C have implantable cardioverter-defibrillators, prohibiting the use of MRI Thirty-one patients (19 men; mean age 41 ± 12 years) referred for evaluation of known or suspected ARVD/C had a complete reevaluation including contrast-enhanced cardiac MDCT at the center Two patients underwent both cardiac MRI and MDCT Seventeen of 31 patients met Task Force criteria for ARVD/C and were confirmed to have ARVD/C Multidetector computed tomographic images were analyzed for qualitative and quantitative characteristic findings of ARVD/C Increased RV trabeculation (p
TL;DR: Equipment requirements are presented, and a comprehensive description of the methods needed to complete a CMR exam including the animal preparation, imaging, and image analysis are discussed, and the advanced applications of myocardial tagging and delayed-contrast-enhanced imaging are reviewed for the assessment of regional contractile function and myocardIAL viability.
TL;DR: Early postinfarction left ventricular restraint early after myocardial infarction limits infarct expansion and improves borderzone contractile function.
TL;DR: It is feasible to obtain LV pressure–volume and stress–length diagrams in patients based on the present novel methodological approach of using CMR and invasive pressure measurement and most likely, deterioration of myocardial work is crucial for the prognosis.
Abstract: In experimental animals, cardiac work is derived from pressure-volume area and analyzed further using stress-length relations. Lack of methods for determining accurately myocardial mass has until now prevented the use of stress-length relations in patients. We hypothesized, therefore, that not only pressure-volume loops but also stress-length diagrams can be derived from cardiac volume and cardiac mass as assessed by cardiac magnetic resonance imaging (CMR) and invasively measured pressure. Left ventricular (LV) volume and myocardial mass were assessed in seven patients with aortic valve stenosis (AS), eight with dilated cardiomyopathy (DCM), and eight controls using electrocardiogram (ECG)-gated CMR. LV pressure was measured invasively. Pressure-volume curves were calculated based on ECG triggering. Stroke work was assessed as area within the pressure-volume loop. LV wall stress was calculated using a thick-wall sphere model. Similarly, stress-length loops were calculated to quantify stress-length-based work. Taking the LV geometry into account, the normalization with regard to ventricular circumference resulted in "myocardial work." Patients with AS (valve area 0.73+/-0.18 cm(2)) exhibited an increased LV myocardial mass when compared with controls (P<0.05). LV wall stress was increased in DCM but not in AS. Stroke work of AS was unchanged when compared with controls (0.539+/-0.272 vs 0.621+/-0.138 Nm, not significant), whereas DCM exhibited a significant depression (0.367+/-0.157 Nm, P<0.05). Myocardial work was significantly reduced in both AS and DCM when compared with controls (129.8+/-69.6, 200.6+/-80.1, 332.2+/-89.6 Nm/m(2), P<0.05), also after normalization (7.40+/-5.07, 6.27+/-3.20, 14.6+/-4.07 Nm/m(2), P<0.001). It is feasible to obtain LV pressure-volume and stress-length diagrams in patients based on the present novel methodological approach of using CMR and invasive pressure measurement. Myocardial work was reduced in patients with DCM and noteworthy also in AS, while stroke work was reduced in DCM only. Most likely, deterioration of myocardial work is crucial for the prognosis. It is suggested to include these basic physiological procedures in the clinical assessment of the pump function of the heart.
TL;DR: The results of tissue characterization of the myocardium by T1 quantification and MRI findings in a patient with cardiac amyloidosis and in combination with other MR findings suggestive of amyloidsosis may increase diagnostic confidence.
Abstract: In cardiac amyloidosis an interstitial deposition of amyloid fibrils causes concentric thickening of the atrial and ventricular walls. We describe the results of tissue characterization of the myocardium by T1 quantification and MRI findings in a patient with cardiac amyloidosis. The T1 time of the myocardium was elevated compared to that in individuals without amyloidosis. The T1 time of the myocardium was 1387 +/- 63 msec (mean value obtained from four measurements +/- standard deviation [SD]) in the patient with cardiac amyloidosis, while the reference value obtained from the myocardium of 10 individuals without known myocardial disease was 1083 +/- 33 msec (mean value +/- SD). In combination with other MR findings suggestive of amyloidosis, such as homogeneous thickening of the ventricular and atrial walls, thickening of the valve leaflets, restrictive filling pattern, and reduction of systolic function, T1 quantification may increase diagnostic confidence.
TL;DR: It is concluded that cardiac hypertrophy is present only in a minority of adult FA patients, and MRI is recommended as the most accurate assessment of cardiac anatomy in vivo.
Abstract: Cardiomyopathy is an important and frequently life limiting manifestation of Friedreich's ataxia (FA), the most prevalent form of autosomal recessive ataxia. Left ventricular mass is used as primary outcome measure in recent intervention studies but systematic analyses of FA cardiomyopathy are sparse. To assess cardiac hypertrophy by cardiac magnetic resonance imaging (MRI) in vivo, we assessed 41 adult patients with genetically confirmed FA and 33 age- and sex-matched healthy controls by cardiac MRI and echocardiogarphy. Septal hypertrophy and left ventricular mass index were determined by two independent raters. MRI revealed hypertrophy of the interventricular septum in 40% and increased left ventricular mass index in 29% of patients. Interobserver variability was less than 5% for both measures. GAA repeat length had only minor influence on interventricular septum thickness. Left ventricular mass index decreased with age. Severity of ataxia did not correlate with cardiac disease. In echocardiography wall diameter was assessable only in 31 of 41 FA patients with 32% of patients presenting septal hypertrophy and 6% increased left ventricular mass index. We conclude that cardiac hypertrophy is present only in a minority of adult FA patients. If despite this limitation intervention studies use left ventricular mass as outcome measure, MRI is recommended as the most accurate assessment of cardiac anatomy in vivo.
TL;DR: Cardiac magnetic resonance accurately depicts SVD anatomy and associated anomalous pulmonary venous drainage, provides quantitative information on the hemodynamic burden, and reveals additional cardiovascular abnormalities.
Abstract: Sinus venosus defect (SVD) is an uncommon type of interatrial communication in which cardiac magnetic resonance (CMR) is increasingly used as an alternative imaging modality The goal of this study was to determine the accuracy of CMR in patients with SVD compared with surgical findings The diagnostic studies and operative reports of all patients who had CMR followed by surgical repair of SVD (n = 16) from 1996 to 2005 were reviewed and discrepancies were recorded CMR studies included assessment of anatomy (evaluated by a combination of gradient echo cine, spin echo, and gadolinium-enhanced three-dimensional magnetic resonance angiography), ventricular volumes and function, and flow measurements The median age at CMR was 14 years (range, 04-42) Compared with operative findings, there were no major discrepancies with CMR The SVD was clearly imaged in all patients and 36 anomalously draining pulmonary veins were identified The median pulmonary-to-systemic flow ratio was 24 (range, l3-46) Patients had an average of 17 previous diagnostic tests (range, 1-3; 19 transthoracic echo, 5 catheterizations, and 3 transesophageal echo) Before CMR, SVD was diagnosed in 1 patient, suspected in 7, and not suspected in 8 Additional unsuspected findings identified by CMR included malposition of septum primum (n = 2), left superior vena cava to coronary sinus (n = 2), and aortic arch anomalies (n = 2) CMR accurately depicts SVD anatomy and associated anomalous pulmonary venous drainage, provides quantitative information on the hemodynamic burden, and reveals additional cardiovascular abnormalities This experience indicates that CMR provides the information necessary for surgical planning of SVD repair
TL;DR: Changes in LA volume and function were age dependent and related to changes in LV mass-volume ratio, suggesting it to be an indicator of diastolic function.
Abstract: Left ventricular (LV) filling results from diastolic suction of the left ventricle and passive left atrial (LA) emptying at early diastole and LA contraction at end-diastole. Effects of aging on LA and LV geometric characteristics and function and its consequences for LV filling are incompletely understood. Insight into these effects may increase the understanding of diastolic function. Cardiac magnetic resonance imaging was used to study effects of aging on left atrioventricular coupling and LV filling. Forty healthy volunteers underwent cardiac magnetic resonance imaging and were subdivided into 2 age groups of 20 to 40 (younger group) and 40 to 65 years (older group). For the older group, LA volumes were larger (p 2 ; p 2 ; p
Journal Article•
TL;DR: Unlike standard diagnostic techniques, cardiac MRI appears to be a rapid and noninvasive means of determining subclinical right myocardial involvement that is otherwise undetected in patients with SSc.
Abstract: OBJECTIVE: To assess myocardial involvement in patients with systemic sclerosis (SSc) with no signs or symptoms of cardiac impairment (New York Heart Association functional class I). METHODS: Fifty patients (45 women, 5 men, age 53.3 +/- 12.9 yrs) who did not complain of serious diseases other than SSc were recruited out of 119 consecutive patients with SSc. Thirty-three were found to have limited cutaneous SSc (lSSc) and 17 diffuse SSc (dSSc). All underwent cardiovascular magnetic resonance imaging (MRI) to determine right and left systolic and diastolic volumes and ventricular ejection fractions (RVEF and LVEF). Thirty-one healthy subjects matched for sex, age, and body surface area (BSA) were studied as controls. Diffusion lung capacity test (DLCO) and high resolution computed tomography were performed to evaluate lung involvement. RESULTS: Disease duration between patients with lSSc (14.1 +/- 11.4 yrs) and those with dSSc (6.9 +/-4.4yrs) was found to be significantly different (p
TL;DR: Myocardial perfusion reserve appears to be the most accurate index to detect anatomical and hemodynamically significant CAD.
TL;DR: A 22-year-old man, whose mother died at 40 years because of sudden death, came to the authors' observation complaining of palpitations and physical examination was unremarkable except for an irregular cardiac rhythm, and his clinical history was otherwise uneventful.
Abstract: A 22-year-old man, whose mother died at 40 years because of sudden death, came to our observation complaining of palpitations. Physical examination was unremarkable except for an irregular cardiac rhythm, and his clinical history was otherwise uneventful. ECG showed frequent ventricular ectopic beats with normal QRS voltages and repolarization (Figure, A). Holter monitoring registered 7.800 polymorphic ventricular ectopic beats frequently occurring in couplets and triplets. Two-dimensional echocardiography showed normal parameters including thickness of cardiac walls, valvular pattern, and left ventricular ejection fraction (68%), and tissue Doppler imaging registered reduced relaxation and contraction velocities, suggesting some myocardial abnormality. Cardiac magnetic resonance imaging failed to show areas of thickened or dysfunctional cardiac wall as well as late-enhancement signals after gadolinium infusion (Figure …
TL;DR: The present approach using a thick-walled sphere model permits determination of mechanical wall stress in a clinical routine setting using standard cardiac MRI protocols and a correlation of BNP concentration with calculated LV stress was observed in vivo.
Abstract: Ventricular loading conditions are crucial determinants of cardiac function and prognosis in heart failure. B-type natriuretic peptide (BNP) is mainly stored in the ventricular myocardium and is released in response to an increased ventricular filling pressure. We examined, therefore, the hypothesis that BNP serum concentrations are related to ventricular wall stress. Cardiac magnetic resonance imaging (MRI) was used to assess left ventricular (LV) mass and cardiac function of 29 patients with dilated cardiomyopathy and 5 controls. Left ventricular wall stress was calculated by using a thick-walled sphere model, and BNP was assessed by immunoassay. LV mass (r = 0.73, p < 0.001) and both LV end-diastolic (r = 0.54, p = 0.001) and end-systolic wall stress (r = 0.66, p < 0.001) were positively correlated with end-diastolic volume. LV end-systolic wall stress was negatively related to LV ejection fraction (EF), whereas end-diastolic wall stress was not related to LVEF. BNP concentration correlated positively with LV end-diastolic wall stress (r = 0.50, p = 0.002). Analysis of variance revealed LV end-diastolic wall stress as the only independent hemodynamic parameter influencing BNP (p < 0.001). The present approach using a thick-walled sphere model permits determination of mechanical wall stress in a clinical routine setting using standard cardiac MRI protocols. A correlation of BNP concentration with calculated LV stress was observed in vivo. Measurement of BNP seems to be sufficient to assess cardiac loading conditions. Other relations of BNP with various hemodynamic parameters (e.g., EF) appear to be secondary. Since an increased wall stress is associated with cardiac dilatation, early diagnosis and treatment could potentially prevent worsening of the outcome.
TL;DR: Extensive LGE reflects greater disease expression and is associated with more severe myocardial damage and with adverse clinical characteristics (e.g., young age at diagnosis, severe hypertrophy, nonsustained ventricular tachycardia, and an ischemic response on exercise), suggesting that it may be closely linked to prognosis.
Abstract: Introduction and objectives In patients with hypertrophic cardiomyopathy, myocardial fibrosis can be detected by late gadolinium enhancement (LGE) on cardiac magnetic resonance imaging. We investigated the relationships between the extent of LGE, left ventricular morphology and function, and clinical characteristics. Methods Both cine and gadolinium-enhanced magnetic resonance imaging were performed in 104 patients with hypertrophic cardiomyopathy. Results
Fifty patients (48%) showed LGE (range: 1–11 segments). The extent of LGE was positively correlated with maximum left ventricular wall thickness ( r =0.53; P r =0.41; P r =0.51; P r =−0.32; P =.001), the magnitude of the subaortic gradient increase during exercise echocardiography ( r =−0.26, P =.023), and age at diagnosis ( r =−0.20; P =.04). Four of the 5 patients with an ischemic response on exercise echocardiography had ≥3 segments showing LGE ( P =.003). Severe hypertrophy (i e, ≥30 mm) and nonsustained ventricular tachycardia occurred more frequently as the number of LGE segments increased ( P P =.04, respectively). Conclusions Extensive LGE reflects greater disease expression. It is associated with more severe myocardial damage (i e, a lower ejection fraction and a larger number of hypokinetic segments) and with adverse clinical characteristics (e g, young age at diagnosis, severe hypertrophy, nonsustained ventricular tachycardia, and an ischemic response on exercise), suggesting that it may be closely linked to prognosis.
TL;DR: To investigate the role of N‐terminal pro‐BNP (NT‐proBNP) for the estimation of right heart failure and pulmonary pressure in patients with atrial septal defects (ASD) before and after percutaneous defect closure.
Abstract: Background:
To investigate the role of N-terminal pro-BNP (NT-proBNP) for the estimation of right heart failure and pulmonary pressure in patients with atrial septal defects (ASD) before and after percutaneous defect closure.
Methods:
We performed correlation analysis for NT-proBNP and right ventricular systolic pressure (RVSP) as well as right ventricular enddiastolic and endsystolic volume (RVEDV, RVESV) determined by cardiac magnetic resonance imaging (MRI) before and up to one year following ASD closure. Additionally NT-proBNP concentrations were correlated with right atrial (RA) and RV enddiastolic pressure (RVEDP), ASD size and interatrial left-to-right shunt.
Results:
Baseline RVSP was 33±8 mmHg, which decreased significantly during follow-up. Initially, NT-proBNP levels were 240±93 pg/ml. After closure, a reduction to 1167±62 pg/ml was obvious (p<0.01). Baseline MRI showed enlarged RV volumes in all individuals. At six and twelve months follow-up a significant reduction of RVEDV and RVESV was apparent. A positive correlation was noted between RV volumes and NT-proBNP (r=0.65, p<0.05). Furthermore RA pressure, RVEDP, RVSP and left-to-right shunt significantly correlated to peptide levels. No correlation was seen between ASD size and NT-proBNP.
Conclusion:
NT-proBNP correlates to right ventricular dilatation, pulmonary pressure and left-to-right shunt in volume load of the right heart caused by an underlying ASD.
01 Jan 2007
TL;DR: The role of Imaging in Cardiac Innervation and Receptors in Heart Failure and the Emerging Role of Molecular Imaging are discussed.
Abstract: Part 1: Instrumentation and Principles of Imaging.- Instrumentation and Principles of PET.- Instrumentation and Principles of CT.- Integrated PET/CT.- Prinicples of Quantitation in Cardiac PET.- Part 2: General Considerations for Performing PET and Integrated PET/CT.- Radiopharmaceuticals for Clinical Cardiac PET Imaging.- Iodinated Contrast Agents for Cardiac CT.- CT Anatomry of the Heart.- Patient and Occupational Dosimetry.- Part 3: Diagnostic Approaches to Patients With Cad.- Patient Preparation and Stress Protocols for Cardiac PET and Integrated PET/CT Imaging.- PET and Integrated PET-CT Myocardial Imaging Protocols and Quality Assurance.- Myocardial Perfusion Imaging with PET.- Quantifying Myocardial Perfusion Imaging with PET.- Quantifying Myocardial Perfusion for the Assessment of Pre-clinical Coronary Artery Disease.- Assessing artherosclerotic burden with CT.- CT Coronary Angiography.- Relative Merits of Coronary CTA and Coronary MRI.- Integrated Assessment of Myocardial Perfusion and Coronary Angiography with PET-CT.- Part 4: Diagnostic Approaches to the Patient with Heart Failure.- PET Measurement of Myocardial Metabolism.- Myocardial Viability Assessment with PET and PET/CT.- Assessment of Myocardial Viability by Cardiac Magnetic Resonance Imaging.- Comparison of Imaging Modalities in the Assessment of Myocardial Viability.- Role of Imaging in Cardiac Innervation and Receptors in Heart Failure.- Part 5: Emerging Role of Molecular Imaging.- Evaluating High-Risk, Vulnerable Plaques with Integrated PET/CT.- Evaluating Vulnerable Atherosclerotic Plaque with MRI.- Evaluating Gene and Cell Therapy.- Imaging of Angiogenesis.- Part 6: Case Illustrations of Cardiac PET and Integrated PET-CT.
TL;DR: A case of TCM with the rare complication of left ventricular thrombus formation is reported and cardiac magnetic resonance imaging aided the diagnosis by characterizing the non-enhancing mass and evaluating the surrounding myocardium for scarring.
Abstract: Transient left ventricular apical hypokinesis results in a typical ampullary shape and has been described as Takotsubo cardiomyopathy (TCM). We report a case of TCM with the rare complication of left ventricular thrombus formation. Cardiac magnetic resonance imaging aided the diagnosis by characterizing the non-enhancing mass and evaluating the surrounding myocardium for scarring.
Journal Article•
TL;DR: Although guidelines can help with treating patients, treatment ultimately should be tailored to each person based on clinical judgment of the a priori risk of a cardiac event, symptoms, and the cardiac risk profile.
Abstract: Noninvasive cardiac imaging can be used for the diagnostic and prognostic assessment of patients with suspected or known coronary artery disease. It is central to the treatment of patients with myocardial infarction, coronary artery disease, or acute coronary syndromes with or without angina. Radionuclide cardiac imaging; echocardiography; and, increasingly, cardiac computed tomography and cardiac magnetic resonance imaging techniques play an important role in the diagnosis of coronary artery disease, which is the leading cause of mortality in adults in the United States. Contemporary imaging techniques, with either stress nuclear myocardial perfusion imaging or stress echocardiography, provide a high sensitivity and specificity in the detection and risk assessment of coronary artery disease, and have incremental value over exercise electrocardiography and clinical variables. They also are recommended for patients at intermediate to high pretest likelihood of coronary artery disease based on symptoms and risk factors. Cardiac magnetic resonance imaging and cardiac computed tomography are newly emerging modalities in the evaluation of patients with coronary artery disease. Cardiac magnetic resonance imaging is useful in the assessment of myocardial perfusion and viability, as well as function. It also is considered a first-line tool for the diagnosis of arrhythmogenic right ventricular dysplasia. Cardiac computed tomography detects and quantifies coronary calcium and evaluates the lumen and wall of the coronary artery. It is a clinical tool for the detection of subclinical coronary artery disease in select asymptomatic patients with an intermediate Framingham 10-year risk estimate of 10 to 20 percent. In addition, cardiac computed tomography is evolving as a noninvasive tool for the detection and quantification of coronary artery stenosis. Although guidelines can help with treating patients, treatment ultimately should be tailored to each person based on clinical judgment of the a priori risk of a cardiac event, symptoms, and the cardiac risk profile.