Predictors of success of the modified maze procedure using radiofrequency device.

The modified maze procedure using radiofrequency devices has become an increasingly common surgical option for patients with atrial fibrillation. Several lesion sets have been proposed and tested, but it remains unclear which yields the best results. We studied 61 patients who underwent the modified maze procedure using radiofrequency devices from March 2005. The pulmonary veins were isolated separately on both sides, and a connecting lesion was made inferiorly in the early series of 30 patients (group 1). In 31 patients (group 2) treated from May 2007, we added a superior connecting lesion between both pulmonary veins (completing a box lesion), and also performed coronary sinus ablation from the epicardial side, using a monopolar device. At 6 months postoperatively, maintenance of sinus rhythm with and without antiarrhythmic medications was 70% and 63%, respectively in group 1, and 94% and 90% in group 2 (both p<0.05). Multivariate analysis indicated that the box lesion with coronary sinus ablation was an independent predictor of the maintenance of sinus rhythm at 6 months. These 2 lesions should not be eliminated from the modified maze procedure.

Elevated levels of neopterin are associated with carotid plaques with complex morphology in patients with stable angina pectoris.

OBJECTIVE: Neopterin is an activation marker for monocytes/macrophages, and circulating levels of neopterin are elevated in patients with coronary complex lesions in unstable angina pectoris. We investigated the possible association between neopterin and complex carotid plaques which may be associated with the risk of ischemic stroke in patients with stable angina pectoris (SAP). METHODS: We measured plasma levels of neopterin in 102 patients with SAP and carotid ultrasound was performed for evaluation of the presence of carotid plaques and plaque surface characteristics categorized as complex or noncomplex. In addition, endarterectomy specimens of extracranial high-grade carotid stenosis with complex plaques from five patients with SAP were immunohistochemically examined with antibodies to smooth muscle cells, endothelial cells, platelets, macrophages, and T cells. RESULTS: Plasma neopterin levels were significantly higher in patients with complex carotid plaques than in those with noncomplex plaques (median [interquartile range]: 24.2 [19.2-39.3]nmol/L vs. 19.4 [11.9-25.1]nmol/L; P=0.01) or without any plaques (18.8 [14.9-23.6]nmol/L; P=0.001). On multivariate logistic analyses after adjustment for traditional atherosclerotic risk factors, multi-vessel coronary disease and high sensitivity C-reactive protein, neopterin levels were independently associated with the presence of complex carotid plaques (adjusted OR 2.21 per SD increase, 95%CI 1.13-4.33, P=0.02). Immunohistochemical staining revealed abundant neopterin-positive macrophages in carotid complex lesions. CONCLUSION: These findings demonstrate that carotid plaques with complex morphology have increased circulating neopterin levels and immunohistochemical localization of neopterin in patients with SAP. Neopterin can be considered an important biomarker of plaque destabilization in carotid artery atherosclerotic lesions in this population.

Comparison of determinations of left atrial volume by the biplane area-length and Simpson's methods using 64-slice computed tomography.

OBJECTIVES: There is increasing evidence that left atrial (LA) size is an important predictor of adverse cardiovascular outcomes such as atrial fibrillation, stroke, and congestive heart failure. The aim of this study was to determine whether there is a difference in results of quantification of LA volume by the area-length and Simpson's methods using multislice computed tomography (MSCT). METHODS AND RESULTS: The study population consisted of 51 patients with sinus rhythm (sinus group) and 20 patients with atrial fibrillation (af group) clinically indicated for MSCT angiography for evaluation of coronary arteries. Maximum LA volume, obtained at end-systole from the phase immediately preceding mitral valve opening, was measured using the area-length and Simpson's methods. In the sinus group, the mean LA volumes, indexed to body surface area, were 48.4+/-17.9 ml/m(2) with the area-length method and 48.3+/-17.0 ml/m(2) with the Simpson's method. In the af group, the mean indexed LA volumes with the area-length method and the Simposon's method were 91.5+/-47.5 ml/m(2) and 90.3+/-45.9 ml/m(2), respectively. LA volumes calculated by the area-length method exhibited a strong linear relationship and agreement with those calculated using Simpson's method in both the groups (sinus group: r=0.99, P<0.0001, af group: r=0.99, P<0.0001). CONCLUSIONS: The area-length method is a simple and reproducible means of assessment of LA volume. Standardization of LA volume assessment using MSCT is important for serial follow-up and meaningful communication of results of testing among institutions and physicians.

Two-dimensional echocardiographic methods for assessment of left atrial volume.

Left atrial (LA) size is an important predictor of cardiovascular events. Various methods of LA volume assessment exist, but their differences have not been defined. This prospective study included 631 patients (331 men; mean age of 68 +/- 14 years) without a history of atrial arrhythmias, stroke, valvular heart disease, pacemaker implantation, or congenital heart disease. All underwent echocardiography with comprehensive diastolic function assessment and LA volume measurement by 3 commonly used methods: biplane area-length, biplane Simpson's method, and the prolate-ellipsoid method. Mean LA volumes were 39 +/- 14 ml/m2 by the area-length method, 38 +/- 13 ml/m2 by the Simpson's method, and 32 +/- 14 ml/m2 by the prolate-ellipsoid method. In 92% of patients, the prolate measurement was smaller than the 2 biplane methods. Pairwise correlations (r) were 0.98 for area-length versus Simpson's, 0.85 for prolate versus area-length, and 0.86 for prolate versus Simpson's (all p values <0.001). For distinguishing normal (n = 62) from pseudonormal diastolic function (n = 240) using receiver-operating curve analysis, areas under the curves were 0.76, 0.78, and 0.75 for the area-length, Simpson's, and prolate methods, respectively (all p values <0.001, no significant intermethod differences). In conclusion, our findings suggest that there are systematic differences among existing LA volume methods. Biplane area-length and Simpson's methods compare closely, whereas the prolate-ellipsoid method generally yields smaller volumes.

Echocardiographic indices of increased left ventricular filling pressure and dilation after acute myocardial infarction.

The relationship between echocardiographic indicators of acute and chronic left ventricular (LV) filling pressure and LV dilation after acute myocardial infarction was assessed in 47 patients. The ratio of early transmitral flow velocity to early mitral annulus velocity (E/e') reflects acute LV filling pressure and the indexed volume of the left atrium is an indicator of chronic LV filling pressure. E/e' was higher (19 vs 10, P = .001) among patients who experienced a greater than 15% increase in indexed LV end-diastolic volume (remodeling group, n = 10). Receiver operating characteristic curve analysis confirmed that E/e' was a predictor of remodeling (area under the curve 0.83, P = .002). Patients with E/e' greater than 15 had a mean increase in indexed LV end-diastolic volume of 9.3 versus 1.7 mL/m2 in patients with E/e' 15 or less (P = .01). Multivariable regression analyses confirmed that E/e' was the strongest independent predictor of remodeling in this cohort (odds ratio 1.39, P = .01). There was no relationship between indexed volume of the left atrium and LV dilation. These data suggest that the E/e' ratio may be a useful predictor of LV dilation after acute myocardial infarction. In particular, an E/e' ratio greater than 15 identifies patients at increased risk.

Prevalence, pathophysiology, and clinical significance of post-heart transplant atrial fibrillation and atrial flutter.

BACKGROUND: Atrial rhythm disturbances, in particular atrial fibrillation (AF) and flutter (AFL), are common in the denervated transplanted heart. However, there is a relative paucity of data in the prevalence, mechanism of arrhythmia, and long-term significance. OBJECTIVES: (1) Determine the prevalence of AF and AFL in heart transplant patients, (2) define the echo/Doppler features associated with arrhythmia, and (3) evaluate the impact of arrhythmia on long-term survival. METHODS: All patients who received an orthotopic heart transplant at the Mayo Clinic, Rochester, Minnesota, between 1988 and 2000 were included. Analysis of serial electrocardiograms and Holter monitor records provided evidence of AF or AFL development. Variables including general patient demographics, histology-proven rejection numbers and grades, results of serial coronary angiography, endomyocardial biopsy specimens, and echocardiographic studies performed at 6 weeks and 3 years after transplant were obtained to determine variables predictive of arrhythmia development. RESULTS: There were 167 heart transplant recipients, of which 16 (9.5%) developed AF and another 25 (15.0%) developed AFL over 6.5 +/- 3.4 years. Patients who developed AF or AFL had lower left ventricular (LV) ejection fractions (56.6% +/- 1.6% vs 62.5% +/- 1.5%, p < 0.05), higher LV end-systolic dimensions (LVESD) (33.6 +/- 1.12 mm vs 29.7 +/- 0.97 mm, p < 0.01), higher right atrial volume indexes (43.2 +/- 12.3 ml vs 35 +/- 5.3 ml, p < 0.03), lower mitral deceleration time (145 +/- 8 msec vs 160 +/- 12 msec, p < 0.05), and lower late mitral annulus tissue a' velocities (0.06 +/- 0.005 cm/sec vs 0.08 +/- 0.01 cm/sec, p < 0.02) compared with an age- and gender-matched Sinus Rhythm Group. Grade 3 rejection was a time-dependent covariate predictor of AFL risk (hazard ratio [HR], 2.95; 95% confidence interval [CI], 1.3-6.6, p < 0.008) but not AF (HR, 2.264; 95% CI, 0.72-7.1; p = 0.10). Thirty-nine of 167 patients died: 13 in the arrhythmia group and 26 in the normal sinus rhythm group. Development of atrial dysrhythmia adversely affected the outcome in the first 5 years (p < 0.001) compared with normal sinus rhythm. Predictors of long-term mortality included AF/AFL (HR, 2.88; 95% CI, 1.38-5.96; p < 0.004), age at transplant (HR, 1.04; 95% CI, 1.00-1.07, p < 0.03), coronary artery disease (HR, 2.655; 95% CI, 1.25-5.64; p = 0.01), pre-transplant cardiac amyloidosis (HR, 5.02; 95% CI 2.37-10.62; p < 0.001), right atrial volume index (HR, 1.03; 95% CI, 1.00-10.7; p = 0.03), mitral deceleration time <160 msec (p < 0.01), and LVESD >30 mm (p < 0.04). CONCLUSION: Development of AF/AFL post-heart transplantation is not uncommon and is associated with decreased long-term survival. Cumulative effects of repeated moderate-to-severe (grade 3 or more) rejections that result in increased cardiac fibrosis are associated with the development of AFL, but not AF. Similarly advanced restrictive diastolic dysfunction caused by fibrosis from repeated moderate-to-severe (grade 3 or more) rejections was predominant in the patients with arrhythmia and was a marker of poor long-term outcome.

Usefulness of real-time intravenous myocardial contrast echocardiography in predicting left ventricular dilation after successfully reperfused acute myocardial infarction.

The ability of real-time intravenous myocardial contrast echocardiography to predict left ventricular remodeling after reperfused acute myocardial infarction was assessed in 47 patients. Intravenous myocardial contrast echocardiography was an independent predictor of left ventricular dilation after acute myocardial infarction. In particular, normal contrast opacification within dyssynergic segments indicated a very low risk of remodeling.

Comparison of accurate measurement of left ventricular mass in patients with hypertrophied hearts by real-time three-dimensional echocardiography versus magnetic resonance imaging.

To evaluate whether left ventricular (LV) mass assessed by a new real-time, 3-dimensional echocardiographic (RT-3DE) system corresponds to cardiac magnetic resonance imaging (MRI) in patients with LV hypertrophy, RT-3DE and 2-dimensional echocardiography (2DE) were performed to calculate LV mass in 21 patients (mean age 54 +/- 15 years) who underwent MRI for the evaluation of LV hypertrophy. In 20 of 21 patients, adequate 3-dimensional data for LV mass analysis were obtained, and regression analysis showed that LV mass by RT-3DE correlated with that determined by MRI (r = 0.95, y = 28.9 + 0.85x) better than with that determined by 2DE (r = 0.70, y = 43.6 + 0.81x). RT-3DE allows the accurate measurement of LV mass in patients with hypertrophied hearts.

Non-invasive assessment of myocardial ischaemia using new real-time three-dimensional dobutamine stress echocardiography: comparison with conventional two-dimensional methods.

AIMS: Although two-dimensional-dobutamine stress echocardiography (2D-DSE) is useful for the diagnosis of myocardial ischaemia, it requires the acquisition of multiple cross-sections at each stage. The introduction of new real-time three-dimensional echocardiography (RT3DE) offers rapid acquisition and 3D display of the entire left ventricle (LV). The purpose was to evaluate real-time three-dimensional-dobutamine stress echocardiography (RT3D-DSE) for the diagnosis of ischaemia using exercise (201)Tl single-photon emission computed tomography (SPECT) as the reference standard, in comparison with 2D-DSE. METHODS AND RESULTS: We performed DSE in 56 consecutive patients who had undergone SPECT because of suspected ischaemia. 3D images by RT3DE were acquired from the apical window after the acquisition of cross-sectional images at every stage of 2D-DSE. Wall motion analysis in RT3DE was performed from anatomical images by cropping the acquired full volume data sets. Mean scanning time for adequate image acquisition at peak stress by RT3D-DSE was shorter than that by 2D-DSE (29+/-4 vs. 68+/-6 s, P<0.0001). RT3DE provided adequate images at success rate of 92% at rest and 89% at peak stress, whereas two-dimensional echocardiography did at 94 and 90%, respectively. The sensitivity, specificity, and accuracy of RT3D-DSE for the detection of coronary artery disease are 86, 80, and 82%, respectively. Those of 2D-DSE are 86, 83, and 84%, respectively. There were no significant differences in the sensitivity, specificity, and accuracy between these two methods (P=1.000). CONCLUSION: RT3D-DSE offers rapid and simple acquisition of the entire LV wall motion and provides feasible and accurate assessment of myocardial ischaemia.

Triphasic mitral inflow velocity with middiastolic filling: clinical implications and associated echocardiographic findings.

To explore underlying mechanisms and clinical implications of middiastolic filling, we measured early and late mitral inflow velocities, deceleration time of early mitral inflow velocity, and early diastolic mitral annular velocity (E') recorded by pulsed wave Doppler echocardiography in 3 cardiac cycles of 35 patients with prominent mitral inflow (middiastolic flow velocity > or = 0.2 m/s). E' was measured at the septal corner of the mitral annulus by Doppler tissue echocardiography from the apical 4-chamber view and was found to be reduced (E' < 0.1 m/s) in all patients; early mitral inflow velocity/E' ratio was > 10 in all but 1 patient. Valsalva maneuver unmasked delayed relaxation in 15 (88%) of 17 patients and abolished middiastolic filling in 10 (59%). Triphasic mitral inflow with middiastolic flow is related to elevated filling pressure, delayed myocardial relaxation, and slow heart rate, indicating advanced diastolic dysfunction.