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Until recently, the only imaging technique for the diagnosis and management of hypertrophic cardiomyopathy (HCM) was two-dimensional echocardiography, and the use of cardiac magnetic resonance imaging (cMRI) was limited to patients with poor acoustic windows. Now, cMRI has gained an essential role in the diagnosis of HCM, providing superior visualization of myocardial hypertrophy-even in remote zones of the left ventricle-and visualization of subtle changes in thickness and contractility over time. The morphologic accuracy of cMRI allows for the differentiation of HCM from other pathologic conditions with hypertrophic phenotype. Moreover, cMRI sheds light on the in vivo fibrotic changes in cardiac ultrastructure, offering an important advantage in the understanding of pathologic mechanisms of the disease, allowing early identification, risk stratification, and timely therapeutic management.

Apical hypertrophic cardiomyopathy (HC) is an uncommon variant of nonobstructive HC with peculiar characteristics. The investigators report a series of 13 consecutive Caucasian patients with a suspicion or diagnosis of apical HC on the basis of electrocardiographic and/or echocardiographic findings who prospectively underwent magnetic resonance imaging with late gadolinium enhancement (LGE) evaluation. All but 1 patient presented T-wave inversion in the anterolateral leads on electrocardiogram, with a mean maximum negative T wave of 7.0 +/- 3.9 mm. Echocardiography provided correct diagnoses in 9/13 patients (69%), while in 4 patients echocardiographic results were normal or inconclusive. Magnetic resonance imaging showed a spadelike morphology of the left ventricle in 6 patients and identified an apical aneurysm in 4. Eleven patients (85%) presented LGE with a mean percentage of 2.3 +/- 2.6% of total left ventricular mass. In 9 (69%) patients LGE was limited to the hypertrophic segments while in 6 (46%) patients it was also present in nonhypertrophic segments. In conclusion, magnetic resonance imaging in patients with apical HC showed a high incidence of apical aneurysms and a peculiar distribution of LGE, that was not limited to hypertrophic segments., (Copyright 2010 Elsevier Inc. All rights reserved.)

Diseases of the thoracic aorta can present with a broad clinical spectrum of symptoms and signs. Their prevalence appears to be increasing in western populations, most likely corresponding to aging and heightened clinical awareness but also influenced by the progress of high-resolution, noninvasive imaging modalities. Among them, MRI provides an excellent visualization of vascular structures and is well suited for evaluation of thoracic aorta disease. Currently, in many centers, noninvasive imaging modalities are the first choice in the cardiovascular system evaluation and diagnosis, reserving conventional angiography for use only before therapeutic intervention. Understanding the principle MRA techniques is essential for acquiring consistent diagnostic images. Basic technical considerations, which include fast spin-echo, fast gradient-echo, and MRA techniques with phase contrast and contrast-enhanced methods, are discussed and applied in the evaluation of acquired thoracic aorta diseases.

Aortic malformations may be associated with other congenital heart abnormalities or may present independently, as incidental findings in asymptomatic patients. For more than 30 years, conventional imaging techniques for detection and assessment of congenital anomalies of the aorta have been chest X-ray, echocardiography and angiography. In recent times, considerable interest in congenital aortic diseases has been shown, due to technical progresses of noninvasive imaging modalities. Among them, magnetic resonance imaging (MRI) almost certainly offers the greatest advantages, especially in young patients in which a radiation exposure must be avoided as much as possible. MRI provides an excellent visualization of vascular structures with a wide field of view, well suited for evaluation of the thoracic aorta malformations. With the implementation of magnetic resonance angiography (MRA) it is also possible to depict any relationship with supra-aortic or mediastinal vessels. Phase contrast technique allows identification of the hemodynamic significance of the aortic alteration. Some technical considerations, which include fast spin-echo, gradient-echo and, especially, MRA techniques with phase-contrast and contrast enhanced methods, are discussed and applied in the evaluation of congenital thoracic aorta diseases.

Introduction: Arrhythmogenic right ventricular dysplasia (ARVD) is a heart muscle disorder in which the pathological substrate is a fatty or fibro-fatty replacement of the right ventricular (RV) myocardium., Methods and Results: Magnetic resonance imaging (MRI) studies were performed in 10 patients with arrhythmogenic right ventricular dysplasia and in 24 matched controls in order to assess right ventricular epicardial/intramyocardial fatty tissue mass, RV myocardial mass, and RV functional parameters. Functional abnormalities were found in all ARVD cases. Patients with ARVD showed increased fatty tissue compared to controls (8.2 +/- 4 g vs. 2.0 +/- 1.0 g; P = 0.001), whereas no significant differences were found in RV myocardial mass (29.5 +/- 9.2 g vs. 23.2 +/- 6.7 g; P = NS). A correlation coefficient between 0.87 and 0.97 was found for repeated measurements., Conclusion: Quantification of fatty tissue with MRI is feasible and constitutes an objective method for differentiating normal from pathological conditions. This approach may lead to a complete diagnostic assessment of ARVD with the potential application for monitoring the evolution of the disease.

Objective: Aneurysms or dissections can involve multiple aortic segments in patients with Marfan syndrome, requiring staged replacement of the entire aorta. The optimal treatment of descending aortic dissection in these patients is a major challenge. We investigated the feasibility and outcomes of endovascular repair of the descending aorta in patients already submitted to open aortic root/arch surgery. Methods: From March 1998 to July 2008, 12 patients (10 male and 2 female patients; mean age, 37.8 ± 11.6 years) affected by Marfan syndrome underwent endovascular treatment for dissection of the descending aorta after previous open aortic root/arch surgery. Stent graft procedures were performed urgently in 5 patients and electively in 7 patients. Results: Neither in-hospital deaths nor perioperative paraplegia or stroke occurred. Follow-up (median, 31 months; range, 3–57 months) was 100% complete. One patient needed surgical conversion for persistent type I endoleak, leading to false lumen expansion 3 months after endovascular repair. Extension of the dissection occurred in 2 patients 1 month and 2 years after the procedure, respectively. No late death or aortic rupture was observed. Conclusions: Endovascular repair of the dissected descending thoracic aorta can be performed in patients with Marfan syndrome with a low risk of death or major complications. In case of staged procedures, stent graft treatment can be considered a possible alternative to open reoperation. Long-term durability remains to be determined. [Copyright &y& Elsevier]

Abstract: Background: Patients with repaired tetralogy of Fallot (ToF) featuring severe pulmonary regurgitation (PR) and/or right ventricular (RV) dysfunction have reduced exercise tolerance. Aims: To assess the impact of PR and of RV function on the ability to recover from exercise in ToF patients. Methods: 61 consecutive patients aged 23.1±12.1 years underwent maximal cardiopulmonary exercise test (CPX), transthoracic echocardiography and magnetic resonance imaging. This data was compared to those of 153 matched healthy subjects. Results: 19 patients (31%) had severe PR. RV dysfunction was noted in 19 patients (31%). Nine patients (15%) had both severe PR and RV dysfunction. Patients had lower peak oxygen uptake (VO2), VO2 slope, carbon dioxide production (VCO2) slope and O2 pulse slope (p <0.0001), especially those with severe PR and RV dysfunction (p <0.0001). Heart rate slope was similar between groups. No patient with severe PR and RV dysfunction had a predicted peak VO2 >40%. CPX had a high sensitivity and specificity to identify patients with severe PR and RV dysfunction. Conclusions: In ToF patients, severe PR and RV dysfunction lead to delayed recovery from exercise. CPX can identify patients with severe PR and RV dysfunction and may be useful to guide the pulmonary valve replacement decision-making process. [Copyright &y& Elsevier]

Marfan Syndrome and Bicuspid Aortic Valve (BAV) are characterized by the congenital/inherited alteration of the fibrillin proteins of aortic wall extracellular matrix, with higher incidence of aortic dissection/rupture even without aortic dilation. Therefore, early identification and treatment of aortic involvement could improve prognosis. The purpose of this study was to evaluate aortic elastic properties of BAV and Marfan Syndrome patients to identify an index of early aortic involvement. Methods: A Magnetic Resonance Imaging (MRI) study was performed on 38 BAV patients, 20 Marfan patients and 14 healthy volunteers as a control group. A high-resolution gradient-echo sequence was applied in the axial plane at the level of pulmonary artery bifurcation to evaluate aortic distensibility. Results: Aortic distensibility was significantly different among the three groups (ANOVA, p = 0.0001) and was sensibly reduced in BAV (0.0056 ± 0.0048 versus 0.025 ± 0.006 control group) and Marfan (0.0085 ± 0.006 versus 0.025 ± 0.006 control group). Intraobserver and interobserver reproducibility for diastolic measurements were 1.2% and 0.4% respectively and for systolic measurements, they were 1.1% and 0.3% respectively. Conclusion: In BAV or Marfan Syndrome patients, MRI evaluation of abnormal distensibility may provide a reliable index of early aortic involvement, even before aortic dilation occurs. [ABSTRACT FROM AUTHOR]

Patients after aortic dissection repair still have long-term unfavorable prognosis and need careful monitoring. The purpose of this study was to analyze the evolution of aortic dissection after surgical repair in correlation to anatomic changes emerging from systematic magnetic resonance imaging (MRI) follow-up. Between January 1992 and June 1998, 70 patients underwent surgery for type A aortic dissection. Fifty-eight patients were discharged from the hospital (17% operative mortality) and were followed by serial MRI for 12 to 90 months after surgery. In all, 436 postoperative MRI examinations were analyzed. In 13 patients (22.5%) no residual intimal flap was identified, whereas 45 patients (77.5%) presented with distal dissection, with a partial thrombosis of the false lumen in 24. The yearly aortic growth rate was maximum in the descending aortic segment (0.37 +/- 0.43 cm) and was significantly higher in the absence of thrombus in the false lumen (0.56 +/- 0.57 cm) (p <0.05). There were 4 sudden deaths, with documented aortic rupture in 2. Sixteen patients underwent reoperation for expanding aortic diameter. In all but 1 patient, a residual dissection was present (in 13 without any thrombosis of the false lumen). Close MRI follow-up in patients after dissection surgical repair can identify the progression of aortic pathology, providing effective prevention of aortic rupture and timely reoperation. Thrombosis of the false lumen appears to be a protective factor against aortic dilation. [ABSTRACT FROM AUTHOR]

This study was designed to assess the role of magnetic resonance imaging in the differential diagnosis of amyloid and idiopathic etiology of cardiomyopathy. This technique demonstrated the capability to differentiate the 2 forms, providing high-resolution evaluation of the myocardial wall and detecting the infiltrative pathology by tissue characterization. [ABSTRACT FROM AUTHOR]

Abstract: Background: We sought to assess the impact of persistent hypoplasia of the transverse aortic arch (TAA) after repair of aortic coarctation (AoC), on blood pressure response to exercise, left ventricular (LV) hypertrophy and presence of collateral circulation. Methods: 34 consecutive patients with end-to-end repair of AoC (age at repair 3.2±2.5 years) underwent exercise echocardiography and magnetic resonance imaging (MRI) at 24±7 years of age (range 11.3 to 44.6 years). Systolic Doppler pressure gradient (SPG) across the descending aorta and blood pressure at the right arm were measured at baseline and every minute throughout all exercise. Magnetic resonance imaging was used to measure LV mass index, presence and amount of collateral flow, and the diameters of the aortic isthmus and TAA indexed to the diameter of the diaphragmatic. Results: Aortic isthmus index was higher than that of the TAA (p =0.006). We observed LV hypertrophy in 15 patients (45%) and presence of collateral circulation in 14 (41%). Eighteen patients (53%) had an abnormal blood pressure response to exercise. Patients with abnormal pressure response to exercise had smaller TAA index (p =0.0005), but similar aortic isthmus index (p =0.09). They also had higher exercise SPG (p <0.0001), higher LV mass index (p <0.0001) and prevalence of LV hypertrophy (p =0.007), higher prevalence of collateral circulation (p <0.0001) and a higher amount of collateral flow (p <0.0001). TAA index, but not aortic isthmus index, correlated with exercise blood pressure (r =−0.59, p =0.003), exercise SPG (r =−0.70, p =0.0005), amount of collateral flow (r =−0.74, p =0.0002) and LV mass index (r =−0.68, p =0.0007). Conclusions: After repair of AoC, hypoplasia of the TAA may be responsible for abnormal blood pressure response to exercise, persistence of collateral circulation and LV hypertrophy. [Copyright &y& Elsevier]