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Repair of Complete Atrioventricular Septal Defect with Tetralogy of Fallot:

JOURNAL OF CARDIAC SURGERY, Issue 2 2004
Literature Review, Our Experience
Materials and Methods: Between January 1990 and January 2002, 17 consecutive children with CAVSD-TOF underwent complete correction. Nine patients (53%) underwent previous palliation. Mean age at repair was 2.9 ± 1.9 years. Mean gradient across the right ventricular outflow tract was 63 ± 16 mmHg. All children underwent closure of septal defect with a one-patch technique, employing autologous pericardial patch. Maximal tissue was preserved for LAVV reconstruction by making these incisions along the RV aspect of the ventricular septal crest. LAVV annuloplasty was performed in 10 (59%) patients. Six patients (35%) required a transannular patch. Results: Three (17.6%) hospital deaths occurred in this series. Causes of death included progressive heart failure in two patients and multiple organ failure in the other patient. Two patients required mediastinal exploration due to significant bleeding. Dysrhythmias were identified in 4 of 11 patients undergoing a right ventriculotomy versus none of the patients undergoing a transatrial transpulmonary approach (p = ns). The mean intensive care unit stay was 3.2 ± 2.4 days. Two patients required late reoperation due to severe LAVV regurgitation at 8.5 and 21 months, respectively, after the intracardiac complete repair. The mean follow-up time was 36 ± 34 months. All patients survived and are in NYHA functional class I or II. The LAVV regurgitation grade at follow-up was significantly lower than soon after operation, 1.1 ± 0.4 versus 1.7 ± 0.5 (p = 0.002). At follow-up, the mean gradient across the right ventricular outflow tract was 17 ± 6 mmHg, significantly lower than preoperatively (p < 0.001). Conclusions: Complete repair in patients with CAVSD-TOF seems to offer acceptable early and mid-term outcome in terms of mortality, morbidity, and reoperation rate. Palliation prior to complete repair may be reserved in specific cases presenting small pulmonary arteries or severely cyanotic neonates. The RVOT should be managed in the same fashion as for isolated TOF; however, a transatrial transpulmonary approach is our approach of choice. (J Card Surg 2004;19:175-183) [source]

Echo-Tracking Assessment of Carotid Artery Stiffness in Patients with Aortic Valve Stenosis

ECHOCARDIOGRAPHY, Issue 7 2009
Francesco Antonini-Canterin M.D.
Background: There is little information about mechanical properties of large arteries in patients (pts) with aortic stenosis (AS). Methods: Nineteen patients with AS (aortic valve area: 0.88 ± 0.29 cm2) and 24 control subjects without AS but with a similar distribution of risk factors were recruited. , index, pressure-strain elastic modulus (Ep), arterial compliance (AC), augmentation index (AIx), and local pulse-wave velocity (PWV) were obtained at the level of right common carotid artery (CCA) by a real time echo-tracking system. Time to dominant peak of carotid diameter change waveform, corrected for heart rate (tDPc), and maximum rate of rise of carotid diameter (dD/dt) were measured. Systemic arterial compliance (SAC) was also calculated. Parameters of AS severity (mean gradient, valve area, stroke work loss [SWL]) were determined. Results: tDPc was higher in patients with AS than in controls (7.9 ± 0.6 vs. 6.6 ± 0.7, P < 0.0001) while dD/dt was lower (5.3 ± 3.6 mm/s vs. 7.8 ± 2.8 mm/s, P = 0.01). AIx was significantly higher in AS group (32.5 ± 13.6% vs. 20.6 ± 12.2%, P = 0.005) and had a linear correlation both with tDPc (r = 0.63, P < 0.0001) and with dD/dt (r =,0.38, P = 0.01). There was a significant correlation between carotid AC and SAC (r = 0.49, P = 0.03), but only carotid AC was related to SWL (r = 0.51, P = 0.02), while SAC was not (P = 0.26).Conclusions: AIx was the only parameter of arterial rigidity found to be higher in patients with AS than in controls. Carotid AC showed a significant correlation with SAC and it seemed to be more closely related to AS severity than to SAC. [source]

Repair of Complete Atrioventricular Septal Defect with Tetralogy of Fallot:

Dynamic T1 estimation of brain tumors using double-echo dynamic MR imaging

JOURNAL OF MAGNETIC RESONANCE IMAGING, Issue 1 2003
Yoshiyuki Ishimori RT
Abstract Purpose To assess the clinical utility of a new method for real-time estimation of T1 during the first pass of contrast agent by using this method to examine brain tumors. Materials and Methods The multi-phase spoiled gradient-echo pulse sequence using the double-echo magnetic resonance (MR) technique was modified. In the first half of the pulse sequence, the flip angle was varied systematically. Then, static T1 values were calculated using differences in MR signal intensities between different flip angles. In the latter half of this sequence, changes in absolute T1 were calculated using differences in signal intensities before and after injection of contrast agent. The double-echo MR data were used to minimize the T2* effect. Five cases of neurinoma and seven cases of meningioma were examined. Changes in T1 during the first pass of contrast agent were compared between neurinoma and meningioma. Results Changes in absolute T1 were clearly demonstrated on the parametric map. Although the changes in absolute T1 during the first pass of contrast agent did not allow differentiation between the two types of tumors, the mean gradient after the first pass was statistically higher for neurinoma than for meningioma (P < 0.05; meningioma, 0.011 ± 0.012 second,1/second; neurinoma, 0.034 ± 0.020 second,1/second). Conclusion The present method appears to be useful for estimation of dynamic T1 changes in brain tumors in clinical settings. J. Magn. Reson. Imaging 2003;18:113,120. © 2003 Wiley-Liss, Inc. [source]

Influence of perfusion on high-intensity focused ultrasound prostate ablation: A first-pass MRI study,

MAGNETIC RESONANCE IN MEDICINE, Issue 1 2007
Marlène Wiart
Abstract Our aim was to evaluate the influence of regional prostate blood flow (rPBF) on high-intensity focused ultrasound (HIFU) treatment outcome. A total of 48 patients with clinically localized prostate cancer were examined by dynamic contrast-enhanced (DCE)-MRI prior to HIFU therapy. A prostate-specific antigen (PSA) nadir threshold of 0.2 ng/ml was used to define the populations of responders and nonresponders. A dedicated tracer kinetic model, namely "monoexponential plus constant" (MPC) deconvolution, was implemented to provide quantitative estimates of rPBF. The results were compared with those obtained by semiquantitative (steepest slope, mean gradient) and quantitative (Fermi deconvolution) approaches. Of the four methods studied, quantitative rPBF obtained by MPC deconvolution proved the most sensitive to the perfusion changes encountered in this study. Furthermore, blood-flow values obtained with MPC deconvolution in the prostate and muscle (12 ± 8 and 5 ± 3 ml/min/100 g, respectively) were in good agreement with literature data. The mean pretreatment rPBF obtained with MPC deconvolution was significantly higher in nonresponders compared to responders (16 ± 9 vs. 10 ± 6 ml/min/100 g), suggesting a correlation between baseline perfusion and treatment outcome. The present work describes and validates the use of dynamic MRI to estimate rPBF in patients, which in the future may help to refine the conduct of HIFU therapy. Magn Reson Med 58:119,127, 2007. © 2007 Wiley-Liss, Inc. [source]

Patient-Prosthesis Mismatch After Small-Size Stentless Aortic Valve Replacement

JOURNAL OF CARDIAC SURGERY, Issue 2 2004
Sandro Gelsomino M.D.
Methods: Sixty-two patients (mean age 70.9 ± 5.2 years, 77.8% females), receiving a labeled 21,23 mm CLOB between 1993 and 2000, were retrospectively studied. Effective orifice area (EOA) was calculated by the continuity equation and then indexed to the patient's body surface area (BSA) to obtain the indexed EOA (EOAI). Based on previous observations a mismatch was defined as EOAI , 0.85 cm2/m2. Results: Twelve patients (20%) at discharge, two (3.3%) at 6 months and none at late controls had an EOAI , 0.85 cm2/m2. At ANOVA determinants of mismatch were female sex (p < 0.001), age (p = 0.01), and patient's annulus index (PAI, p < 0.001). Patients with mismatch had higher mean gradients (MG, p = 0.01, and p < 0.001 at discharge and 6 months, respectively) and EOAI correlated with MG at discharge (r2= 0.72, p < 0.001) and 6-month (r2= 0.40, p = 0.001) studies. At 1 year no difference in MG was detected between patients with or without mismatch (p = ns) and EOAI did not correlate with MG (r2= 0.01, p = ns). Midwall fractional shortening did not differ in patients with or without mismatch (p = ns). Patients with an EOAI , 0.8 cm/m2 showed an earlier concentric remodeling up to 1 year; no difference was demonstrated at later studies between groups. Survival and clinical status results were not affected by an EOAI , 0.85 cm2/m2. Conclusions: After AVR with CLOB mismatch occurred early postoperatively in a small number of patients without clinical repercussions. EOAI, significantly increasing over time, was adequate to BSA in all patients at late controls. (J Card Surg 2004;19:91-97) [source]