Comparison of the accuracy of multidetector computed tomography versus two-dimensional echocardiography to measure left atrial volume.

Left atrial (LA) volume is an important prognostic factor in cardiovascular disease. Multidetector computed tomography (MDCT) is an emerging cardiac imaging modality; however, its accuracy in measuring the LA volume has not been well studied. The aim of our study was to determine the accuracy of MDCT in quantifying the LA volume. A total of 48 patients underwent MDCT and 2-dimensional (2D) echocardiography (2DE) on the same day. The area-length and Simpson's methods were used to obtain the 2D echocardiographic LA volume. The LA volume assessment by MDCT was obtained using the modified Simpson's method. Four artificial phantoms were created, and their true volume was assessed by an independent observer using both imaging modalities. The correlation between the LA volume by MDCT and 2DE was significant (r = 0.68). The mean 2D echocardiographic LA volume was lower than the LA volume obtained with MDCT (2DE 79 +/- 37 vs MDCT 103 +/- 32, p <0.05). In the phantom experiment, the volume obtained using MDCT and 2DE correlated significantly with the true volume (r = 0.97, p <0.05 vs r = 0.96, p <0.05, respectively). However, the mean 2D echocardiographic phantom volume was 16% lower than the true volume (2DE, Simpson's method 53 +/- 24 vs the true volume 61 +/- 24, p <0.05). The mean volume calculated using MDCT did not differ from the true volume (MDCT 60 +/- 21 vs true volume 61 +/- 24, p = NS). 2DE appeared to systematically underestimate the LA volume compared to phantom and cardiac MDCT, suggesting that different normal cutoff values should be used for each modality. In conclusion, LA volume quantification using MDCT is an accurate and feasible method.

Pulmonary vein contraction: characterization of dynamic changes in pulmonary vein morphology using multiphase multislice computed tomography scanning.

BACKGROUND: The presence and extent of contraction within the pulmonary veins (PVs) have not been defined clearly. OBJECTIVE: The purpose of this study was to determine whether PV contraction exists and can be visualized using multislice computed tomography (MSCT) scanning as this may indicate that this modality may be useful for monitoring patients after PV isolation procedures. METHODS: Analysis was performed on 29 patients (mean age 57.5 +/- 12 years) undergoing MSCT for suspected coronary artery disease without structural heart disease or left atrial anatomical variants. Multiplane reconstructions were used to measure PV diameters at 0, 5, 10, and 15 mm from the ostium in two phases (maximum and minimum size). The ejection fractions of three 5-mm segments were calculated for each PV. RESULTS: Right-sided and left-sided PV contraction and maximal atrial contraction occurred at a median of 85% and 95% of the cardiac cycle, respectively. The temporal concordance of minimal PV volume during peak atrial contraction indicated that the PV volume changes are secondary to active contraction rather than passive reflux and PV distension. The ejection fractions were highest in the superior veins: right superior PV (36.7%, 27.8%, and 16%, respectively, for the three segments from proximal to distal) and left superior PV (26.9%, 21.3%, and 12.1%), in comparison with the right inferior PV (21.1%, 6.6%, and -0.7%) and left inferior PV (15%, 9.3%, and 7.6%). CONCLUSION: Volume changes related to active PV contraction occur extending up to 15 mm into the veins, and this effect is most pronounced in the superior veins.

Incremental diagnostic yield of pediatric cardiac assessment after fetal echocardiography in the offspring of women with congenital heart disease: a prospective study.

OBJECTIVE: We sought to determine the incremental diagnostic utility of pediatric cardiac assessment in the offspring of women with congenital heart disease who have had previous fetal echocardiography. PATIENTS AND METHODS: We prospectively followed pregnant women with congenital heart disease who were receiving care at 2 obstetric and cardiac centers and identified 276 infants who underwent both fetal echocardiography and pediatric cardiac assessment. All of the infants with abnormal fetal echocardiography findings or abnormal pediatric cardiac assessments underwent subsequent confirmatory pediatric echocardiography. RESULTS: In this cohort, congenital heart disease was detected in 22 (8%) of 276 offspring born to women with congenital heart disease. There was concordance between the results of fetal echocardiography and pediatric cardiac assessment in 235 (85%) of 276 offspring (231, both normal; 4, both abnormal) and discordance between the results of fetal echocardiography and pediatric cardiac assessment in 41 (15%) of 276 infants. In the 41 subjects with discordant results, there were normal fetal echocardiography findings but abnormal pediatric cardiac assessments in 35 of 41 (pediatric echocardiography revealed congenital heart disease in 18 of 35 and normal anatomy in 17 of 35) and abnormal fetal echocardiography findings but normal pediatric cardiac assessments in 6 of 41 (pediatric echocardiography findings normal in all 6 of the infants). Fetal echocardiography detected all of the major forms of congenital heart disease. Lesions missed by fetal echocardiography but detected on pediatric cardiac assessment included shunt lesions and minor valvular abnormalities. CONCLUSIONS: Although fetal echocardiography can reliably exclude major forms of congenital heart disease, minor congenital heart disease lesions can be missed on fetal echocardiography; however, these can be diagnosed with careful pediatric cardiac assessment. Postnatal pediatric cardiac assessment has incremental diagnostic utility for the detection of congenital heart disease in the offspring of women with congenital heart disease and previous fetal echocardiography.

Inflammation and infection in nine surgically explanted Medtronic Freestyle stentless aortic valves.

BACKGROUND: The Medtronic Freestyle valve is fixed in glutaraldehyde at zero pressure on the cusps and treated with alpha-amino oleic acid. This valve reportedly has excellent clinical and hemodynamic results, but little has been reported about its long-term pathology. METHODS AND RESULTS: Nine Freestyle valves explanted between 2003 and 2005 were reviewed to assess the reasons for bioprosthesis failure (six implanted at our institution). All valves were examined in detail, using histochemistry and immunohistochemistry to identify the cellular response. One Freestyle valve, explanted for mitral valve endocarditis on the fifth postoperative day, was excluded from analysis. Average implant duration was 52.8+/-35.5 months. Four valves were explanted for infective endocarditis, three for aortic insufficiency, two for aortic stenosis with cusp calcification seen in five valves, pannus and thrombus in all valves and a chronic inflammatory reaction involving the xenograft arterial wall seen in eight of nine valves. This was associated with significant damage to the porcine aortic wall in seven cases, and cusp myocardial shelf damage in six cases. CONCLUSIONS: In this series of valves, we found (1) infective endocarditis; (2) pannus, thrombus, and calcification; and (3) unusual and significant inflammatory reaction and aortic tissue damage, which could by itself lead to aortic incompetence.

A Carpentier-Edwards porcine-valved dacron conduit: at twenty-five years.

We report the longest duration of implantation of a porcine bioprosthesis in the English language literature--a Carpentier-Edwards valved conduit excised after twenty-five years. This 50-year-old man had undergone a modified Fontan operation for tricuspid atresia. He presented with progressive dyspnea, fatigue and edema. The bioprosthesis' dysfunction was due to the pathologic findings of pannus, significant thrombus (on the sinus surface of a cusp), mild structural valve deterioration and pseudo-intimal formation within the conduit. The bioprosthesis' longevity is likely related to low-pressure circulation in the right heart and to host tissue (pannus) overgrowth that covered the cusps and thereby reduced tissue degeneration.

Infective endocarditis of the tricuspid valve.

Infective endocarditis (IE) usually involves the left-sided valves, and IE involving the tricuspid valve (TV) is rare, often developing in intravenous drug users (IDU). We present a case of a 32-year-old male, an intravenous drug abuser (IDA), who presented with nonspecific septic symptoms, and was treated with TV conserving surgery. Pathological examination confirmed tissue destruction, friable thrombotic vegetations, and microorganisms in the leaflet tissue.

Morphological findings in 192 surgically excised native mitral valves.

INTRODUCTION: Mitral valve disease (MVD) is a significant clinical problem that is becoming more common in the 21st century. The pathogenesis of MVD seems to be changing and is not well understood. PATIENTS AND METHODS: The present study details the morphological findings in 192 native mitral valves excised over a one-year period at the Toronto General Hospital, Toronto, Ontario. The mean patient age was 59.7+/-12.3 years at operation. RESULTS: There were 106 men (55.2%) and 86 women (44.8%) in the present study. The most frequent changes in the surgically excised valvular leaflets were fibrosis (78.6%) and thickening (66.2%). Fusion (32.3%) and calcification (25.2%) were common changes at the commissures. Chordae tendineae most often showed evidence of thickening (47.9%) and fibrosis (37.0%). In total, 110 valves showed mitral incompetence (57.3%), 72 showed mitral stenosis (37.5%), and 10 showed a combination of stenosis and incompetence (5.2%). CONCLUSIONS: In the present series, MVD was most frequently caused by postinflammatory (rheumatic) valve disease (RVD) (35.9%), followed by myxomatous degeneration (33.3%). Patients with RVD were usually female (66.7%), while those with myxomatous degeneration were more likely to be male (76.6%). RVD remains a significant problem even though the incidence of acute rheumatic fever with cardiac involvement has declined in Canada. This most likely reflects the current sociodemographic composition of the referral population.

The role of pannus in the longevity of an Ionescu-Shiley pericardial bioprosthesis.

As the population ages, bioprosthetic heart valves are increasingly being used to replace diseased native valves. Bioprosthetic valve durability depends on patient age and other factors, but rarely exceeds 15 years. Explanted bioprosthetic valves commonly show tissue degeneration, tears, and calcification. Host tissue overgrowth (pannus), to the extent of interfering with their function, is another finding in bioprostheses that have been in place for long periods. We present a case in which a bovine pericardial valve was explanted after more than 20 years of implantation. The longevity of this pericardial valve may have been related to excessive pannus growth, which most likely protected the valve from earlier failure.

The intricacies of cardiac sarcoidosis: a case report involving the coronary arteries and a review of the literature.

BACKGROUND: Primary cardiac sarcoidosis (CS) is rare, and concomitant involvement of the coronary arteries is rarer still. Successful diagnosis of this disease is difficult due to its nonspecific symptoms which mimic those of idiopathic dilated cardiomyopathy (IDCM). METHODS AND RESULTS: We describe a 47-year-old Caucasian male who underwent orthotopic heart transplant for presumed IDCM. Examination of the explanted heart revealed numerous nonnecrotizing granulomata throughout, similar granulomata in the walls of the large coronary arteries, and large areas of fibrosis. CONCLUSIONS: In cases of IDCM with symptoms of angina or acute coronary syndrome, the possibility of CS should be considered. Herein, we present this case and a review of the relevant literature.

A bicuspid pulmonary valve associated with tetralogy of fallot.

Congenitally bicuspid pulmonary valves are uncommon. When they occur, it is usually in association with other congenital cardiac lesions, most often a tetralogy of Fallot. We present a rare case of a patient with a congenitally bicuspid pulmonary valve who had pulmonary valve and RVOT reconstruction. The patient did well for 17 years, but needed further reconstruction when the pulmonary valve started getting stenosed and RV pressures went up significantly. The pulmonary valve showed fibroses, thickening, and focal calcification.

Is transesophageal echocardiography overused in the diagnosis of infective endocarditis?

Because of its greater sensitivity, transesophageal echocardiography (TEE) is often misused as a screening tool for the exclusion of infective endocarditis (IE) in patients with small clinical probability of the disease. This study examined the role of using TEE exclusively at a Canadian tertiary care center for the diagnosis of IE and determined which clinical variables are most often associated with positive or negative echocardiographic results supporting or refuting the diagnosis.