Postoperative myocardial fibrosis assessment in aortic valvular heart diseases-a cardiovascular magnetic resonance study.

AIMS: Left ventricular remodelling occurs during the chronic course of aortic regurgitation (AR) and aortic stenosis (AS), leading to myocardial hypertrophy and fibrosis. Several studies have shown that extracellular volume fraction (ECV) and indexed extracellular volume (iECV) are important surrogate markers of diffuse myocardial fibrosis (MF). Postoperative data on these cardiovascular magnetic resonance (CMR) extracellular expansion parameters for either AS or AR are scarce. This study aimed to demonstrate the postoperative changes that occur in diffuse MF, and the influence of preoperative MF on the reversal of LV remodelling, in patients with AR or AS. METHODS AND RESULTS: Patients with severe AR or AS and indications for surgery were prospectively enrolled. Patients underwent pre- and postoperative CMR, and ECV and iECV were quantified. Data from 99 patients were analysed (32 with AR and 67 with AS). After surgery, the left ventricle mass index decreased in both groups (AR: 110 vs. 91 g/m2; AS: 86 vs. 68 g/m2, both P < 0.001). The late gadolinium enhancement fraction (AR: preoperative 1.9% vs. postoperative 1.7%, P = 0.575; AS: preoperative 2.4% vs. postoperative 2.4%, P = 0.615) and late gadolinium enhancement mass (AR: preoperative 3.8 g vs. postoperative 2.5 g, P = 0.635; AS: preoperative 3.4 g vs. postoperative 3.5 g, P = 0.575) remained stable in both groups. Preoperative iECV and ECV were greater in the AR group (iECV: 30 mL/m2 vs. 22 mL/m2, P = 0.001; ECV: 28.4% vs. 27.2%, P = 0.048). Indexed extracellular volume decreased after surgery in both groups (AR: 30-26.5 mL/m2, AS: 22-18.2 mL/m2, both P < 0.001); it was still greater in the AR group (AR: 26.5 mL/m2 vs. AS: 18.2 mL/m2, P < 0.001). Postoperative ECV remained stable in the AR group (preoperative 28.4% vs. postoperative 29.9%; P = 0.617) and increased in the AS group (preoperative 27.2% vs. postoperative 28.6%; P = 0.033). CONCLUSION: Patients with both AR or AS presented reduction in iECV after surgery, unfolding the reversible nature of diffuse MF. In contrast to patients with AS, those with AR developed postoperative iECV regression with stable ECV, suggesting a balanced reduction in both intracellular and extracellular myocardial components.

Dissection flap masquerading as double aortic valve: an acquired complication.

Aortic dissection usually presents as an acute emergency and less commonly presents as chronic dissection. Two-dimensional and transoesophageal echocardiographic features of aortic dissection generally show dissection flap, dilated aorta and aortic regurgitation. We report a very unusual and extremely rare case of a 40-year-old female patient with chronic aortic dissection presenting as functional double aortic valve.

Aspects related to analysis and medico-legal assessment in the context of the presence of synthetic cannabinoids in biological material based on the example of AB-CHMINACA.

AIM OF THE STUDY: The aim of this study was to develop and validate a method for the determination of the synthetic cannabinoid AB-CHMINACA in blood, followed by its verification in forensic toxicological practice. MATERIAL AND METHODS: The case of a 41-year-old man admitted to hospital because of scheduled cardiac surgery was discussed. The man died after 12 hours of hospitalization. Based on collected evidence, AB-CHMINACA poisoning was suspected. The identification and determination of AB-CHMINACA in the man's blood was performed by high-performance liquid chromatography coupled with tandem mass spectrometry using electrospray ionization (HPLC-ESI-MS-MS), after prior solid phase extraction. RESULTS: The concentration of AB-CHMINACA determined in the man's blood sample was 0.5 ng/ml. CONCLUSIONS: In the interpretation of the case, it was concluded that AB-CHMINACA had no direct effect on the patient's death, the cause of which was ascertained as chronic heart failure secondary to aortic valve disease, decompensated by pneumonia. However, an indirect impact of side effects resulting from the use of synthetic cannabinoids cannot be ruled out. They might have exacerbated the man's disease process leading to sudden cardiac arrest caused by asystole.

Cardiac magnetic resonance versus transthoracic echocardiography for the assessment and quantification of aortic regurgitation in patients undergoing transcatheter aortic valve implantation.

BACKGROUND: The transthoracic echocardiographic (TTE) evaluation of the severity of residual aortic regurgitation (AR) following transcatheter aortic valve implantation (TAVI) has been controversial and lacks validation. OBJECTIVES: This study sought to compare TTE and cardiac magnetic resonance (CMR) for assessment of AR in patients undergoing TAVI with a balloon-expandable valve. METHODS: TTE and CMR exams were performed pre-TAVI in 50 patients and were repeated postprocedure in 42 patients. All imaging data were analysed in centralised core laboratories. RESULTS: The severity of native AR as determined by multiparametric TTE approach correlated well with the regurgitant volume and regurgitant fraction determined by CMR prior to TAVI (Rs=0.79 and 0.80, respectively; p<0.001 for both). However, after TAVI, the correlation between the prosthetic AR severity assessed by TTE and regurgitant volume and fraction measured by CMR was only modest (Rs=0.59 and 0.59, respectively; p<0.001 for both), with an underestimation of AR severity by TTE in 61.9% of patients (1 grade in 59.5%). The TTE jet diameter in parasternal view and the multiparametric approach (Rs=0.62 and 0.59, respectively; both with p<0.001) showed the best correlation with CMR regurgitant fraction post-TAVI. The circumferential extent of prosthetic paravalvular regurgitation showed a poor correlation with CMR regurgitant volume and fraction (Rs=0.32, p=0.084; Rs=0.36, p=0.054, respectively). CONCLUSIONS: The severity of AR following TAVI with a balloon-expandable valve was underestimated by echocardiography as compared with CMR. The jet diameter, but not the circumferential extent of the leaks, and the multiparametric echocardiography integrative approach best correlated with CMR findings. These results provide important insight into the evaluation of AR severity post-TAVI.

Prosthesis/annulus discongruence assessed by three-dimensional transoesophageal echocardiography: a predictor of significant paravalvular aortic regurgitation after transcatheter aortic valve implantation.

AIMS: Paravalvular aortic regurgitation (AR) is common after transcatheter aortic valve implantation (TAVI). This study aimed to assess the prosthesis/aortic annulus discongruence by three-dimensional (3D) transoesophageal (TOE) planimetry of aortic annulus and its impact on the occurrence of significant AR after TAVI. METHODS AND RESULTS: We included 33 patients who underwent TAVI with a balloon expandable device for severe aortic stenosis. To appraise the prosthesis/annulus discongruence, we defined a 'mismatch index' expressed as: annulus area - prosthesis area. The aortic annulus area was planimetered with 3D TOE, and approximated by circular area formula (π r(2)) using annulus diameter obtained by two-dimensional (2D) TOE. After TAVI, 13 patients (39.3%) developed significant AR (≥2/4). The occurrence of significant AR was associated to the 3D planimetered annulus area (P = 0.04), and the 'mismatch index' obtained through 3D planimetered annulus area (P = 0.03), but not to 'mismatch index' derived of 2D annulus diameter. In multivariate analysis, 'mismatch index' for 3D planimetered annulus area was the only independent predictor of significant AR (odds ratio: 10.614; 95% CI: 1.044-17.21; P = 0.04). The area under the receiver operating characteristic curve for the 'mismatch index' by the 3D planimetered annulus area was 0.76 (95% CI: 0.54-0.92), whereas for 'mismatch index' obtained by the 2D circular area was 0.36 (95% CI: 0.17-0.55). Using the 3D planimetered annulus area as the reference parameter to decide the prosthetic size, the choice would have been different in 21 patients (63%). CONCLUSION: Three-dimensional TOE planimetry of aortic annulus improves the assessment of prosthesis/annulus discongruence and predicts the appearance of significant AR after TAVI.

Incremental role of three-dimensional transesophageal echocardiography in the assessment of mitral-aortic intervalvular fibrosa abscess.

We report a case of an elderly patient in whom live/real time three-dimensional transesophageal echocardiography (3DTEE) provided definitive diagnosis of mitral-aortic intervalvular fibrosa abscess. This could not be done by two-dimensional transthoracic echocardiography (2DTTE) and two-dimensional transesophageal echocardiography (2DTEE). 3DTEE was also helpful in ruling out associated mitral valve endocarditis, which was initially suspected by 2DTEE leading to a mitral valve sparing surgery. Thus, 3DTEE provided incremental information over 2DTTE and 2DTEE in this patient.

Integrated morphologic and functional assessment of the aortic root after different tissue valve root replacement procedures.

OBJECTIVES: This study was undertaken to explore aspects of the hemodynamic function of different biologic tissue aortic valve root replacements. We set out to image and display the spatiotemporal distributions of axially directed blood velocity through the aortic root. METHODS: The flow velocities through a plane transecting the aortic root were measured by 2-dimensional cine phase-contrast magnetic resonance velocity mapping in 44 subjects: 29 patients who had undergone aortic root replacement approximately 10 years previously (13 autografts, 10 stentless xenografts, and 6 homografts) and 15 healthy control subjects. With cine as well as velocity images, aortic sinus dimensions, effective orifice area, and several velocity parameters were measured. Color-coded plots of velocity relative to the sinus cross sections and velocity-time plots were used to compare spatiotemporal distributions of velocity. RESULTS: Peak flow velocity was similar between the autografts (102 ± 28.0 cm/s) and control valves (119 ± 20.0 cm/s) but was higher in xenografts (167 ± 36.0 cm/s) and homografts (206 ± 91.0 cm/s). These measurements showed an inverse relationship with the effective orifice area (7.27 ± 0.20, 4.24 ± 0.81, 3.37 ± 0.32, and 3.28 ± 0.87 cm(2), respectively). Autograft peak flow velocity showed no significant difference from control valve peak flow velocity, despite larger root dimensions (P < .001). The graphic displays provided further spatiotemporal information. CONCLUSIONS: Peak velocities and spatiotemporal flow patterns depend on the type of valve substitute. In the parameters measured, autograft replacements differed least from normal aortic valves.

Cardiac MR assessment of aortic regurgitation: holodiastolic flow reversal in the descending aorta helps stratify severity.

PURPOSE: To assess the utility of holodiastolic flow reversal (HDR) in the descending aorta on velocity-encoded cardiac magnetic resonance (MR) images in the stratification of aortic regurgitation (AR) severity. MATERIALS AND METHODS: This study was approved by the institutional review board, with waiver of informed consent. A total of 80 patients (overall mean age, 49 years ± 18 [standard deviation]; 22 women and 58 men) with clinical indication for cardiac MR imaging of the aorta were analyzed retrospectively. Velocity-encoded MR imaging was used to quantify AR and assess for HDR at the level of the middescending aorta. These indexes were compared with a qualitative integrated echocardiographic evaluation of AR severity. Sensitivity and specificity for HDR in the prediction of substantial AR were determined, and logistic regression analysis (with associated odds ratios and C statistics) was performed, with HDR and regurgitant fraction as independent predictors. An additional 42 patients (overall mean age, 48 years ± 21; 12 female and 30 male) were then prospectively evaluated in similar fashion to evaluate a decision model derived from analysis of the first group. RESULTS: HDR predicted severe AR (echo grade, 4) with high sensitivity (100%) and specificity (93%). HDR was highly specific (100%) but had lower sensitivity (61%) for moderate to severe AR (echo grade, 3-4). Integration of HDR and direct AR quantification into a combined stratification model based on analysis of the primary group showed good predictive results in the validation group, with a C statistic of 0.94 for moderate to severe AR and 0.93 for severe AR. CONCLUSION: HDR in the middescending thoracic aorta observed at cardiac MR is indicative of severe AR and can be used in conjunction with quantified regurgitant values obtained from velocity-encoded MR imaging to stratify AR severity.

Stress Doppler echocardiography in valvular heart diseases: utility and assessment.

This article is a review on the role of stress echocardiography in valvular heart diseases, describing what the validated indications are, how to perform the test and the utility of performing this examination. Most valve diseases are characteristically dynamic and this dynamic component is best appreciated by exercise Doppler echocardiography. Dobutamine stress echocardiography is also useful in patients with severe aortic stenosis and left ventricular dysfunction. The main advantage of stress echocardiography is to concomitantly allow the evaluation of symptoms, exercise capacity and the hemodynamic consequences of valve diseases, especially in patients with severe valve diseases who deny symptoms or present equivocal symptoms. It also provides important prognostic information and may help to optimize surgical timing in difficult cases. Whether these data should be integrated in the management of patients needs further validation.

Echocardiographic and histological assessment of age-related valvular changes in normal rats.

Aging is associated with morphologic and functional alterations of the rat's left ventricle. However, the time-course of valvular function and morphology in normal aging rats has not yet been studied. For this purpose, 30 male Wistar rats (318 +/- 5g, 10 weeks old) underwent serial echocardiograms for 58 weeks under sodium pentobarbital 50 mg/kg IP anesthetization followed by necropsy. Histopathology was also performed in two additional groups of 10 rats at 10 and 30 weeks of age. Regurgitations were considered as any retrograde flow on 2-D or M-mode color Doppler echocardiography. Tricuspid regurgitation was already found at 10 weeks of age and became more frequent with age. Pulmonary, mitral and aortic regurgitation was seldom observed at 10 weeks but became more frequent after 30 weeks. For the mitral and aortic valve, this was also associated with an increase in valvular thickness because of nodular or segmental myxoid leaflet changes. The severity of valvular regurgitations did not increase with age. In conclusion, aging leads to morphologic and functional valvular changes in normal rats. This is important when investigating models of valvular heart disease in small animals.

Clinical and echocardiographic assessment of the Medtronic Advantage aortic valve prosthesis: the Scandinavian multicentre, prospective study.

OBJECTIVE: The aim of this report is the prospective, multicentre evaluation of clinical results and haemodynamic performance of the Medtronic Advantage aortic valve prosthesis. METHODS: From April 2001 to June 2003, 166 patients (male:female 125:41; mean (SD) age 61.8 (11.8) years) received an aortic advantage valve prosthesis. Complete cumulative follow-up was 242.7 patient-years (maximum 3.2; mean 1.6 years). Postoperatively, patients underwent early (within 30 days) and 1 year transthoracic echocardiography. RESULTS: 30 day mortality was 2.4% (n = 4). Kaplan-Meier estimates of freedom from complications and linearised rates were as follows: 96.9 (1.6)% survival; 94.7 (1.3)% (2.06 patients/year) thrombo-embolism; 99.4 (0.6)% (0.4 patients/year) bleeding; 98.8 (0.9)% (0.8 patients/year) non-structural valve dysfunction; 98.8 (0.9)% (0.8 patients/year) reoperation. Valvular mean pressure gradients ranged from 16 (3) mm Hg for size 19 to 7 (2) mm Hg for size 27 and the corresponding effective orifice areas ranged from 1.2 (0.25) to 3.2 (0.66) cm(2). In all, left ventricular mass significantly decreased (p<0.001) and fractional shortening increased (p<0.001) from postoperative to 1 year echocardiography. CONCLUSIONS: Haemodynamic performance and early clinical results of Medtronic advantage in the aortic position were satisfactory and comparable with those of other bileaflet valves in current clinical use.

A new echocardiographic method for the assessment of the severity of aortic regurgitation: color M-mode flow propagation velocity.

PURPOSE: Echocardiographic Doppler methods widely used in assessment of the severity of aortic regurgitation (AR) are considered sensitive and reliable. However, they all have limitations for quantitation of AR. The color M-mode Doppler flow propagation velocity (FPV) method has been shown to provide useful insights in the evaluation of left ventricular diastolic function and appears to be minimally affected with preload changes. Clinical data regarding the value of FPV in the determination of the significance of valvular insuffiencies are lacking. The purpose of this study was to evaluate the use of FPV in measurement of the severity of AR and to compare its reliability with angiography and other echocardiographic methods. METHODS: Twenty-nine patients (13 male, 16 female) who had cardiac catheterization for various reasons before echocardiographic evaluation were included. The mean age was 53.6 +/- 13.4 years. At the time of cardiac catheterization, the degree of AR was assessed as mild in 10 patients, as moderate in 12, and as severe in 7. In all patients, FPV measurements of AR were obtained with color M-mode Doppler in the apical 5-chamber view. Regurgitation jet height and its ratio to left ventricular outflow obtained in the parasternal long axis with color flow Doppler, pressure half-time, and slope of AR obtained with continuous wave Doppler in apical 5-chamber view were other echocardiographic methods chosen for comparison. RESULTS: The mean values of FPV were 93.1 +/- 18.4 cm/s, 49.8 +/- 8.0 cm/s, and 31.7 +/- 4.9 cm/s in severe, moderate, and mild AR groups, respectively (P <.001). Significant correlation was observed between angiographic grades, FPV, pressure half-time, slope, and jet height and ratio to left ventricular outflow (P <.0001, r = 0.93; P <.0001, r = -0.81; P <.0001, r = 0.76; P <.0001, r = 0.92, respectively). CONCLUSION: FPV is a simple, practical, and reliable method for the quantification of AR.

Two-dimensional echocardiographic assessment of the progression of aortic root size in 127 patients with chronic aortic regurgitation: role of the supraaortic ridge and relation to the progression of the lesion.

Although aortic root dilation has etiologic and prognostic significance in patients with chronic aortic regurgitation (AR), no information is available regarding changes over time in aortic root size in patients with the entire spectrum of AR severity or how such changes relate to progression of the AR or to left ventricular (LV) overload. To analyze this, a total of 127 patients with chronic AR who had more than 6 months of follow-up by two-dimensional and Doppler echocardiography were included in the study (69 men and 58 women; mean age 59.3 +/- 21.2 years [range 14 to 94 years]; 67 cases of mild, 45 moderate, 15 severe, and 21 bicuspid aortic valve disease). The aortic anulus, sinuses of Valsalva, supraaortic ridge, and ascending aorta were measured in the parasternal long-axis view, LV volumes were calculated (biplane Simpson's approach), and the severity of AR was quantified based on proximal jet size and graded according to an algorithm that takes into account major color Doppler criteria. At entry to the study, significant differences between patients with mild, moderate, and severe AR were noted only in supraaortic ridge size (1.46 +/- 0.29 cm/m2 vs 1.63 +/- 0.33 cm/m2 [p < 0.006]; vs 1.67 +/- 0.43 cm/m2 [p < 0.03]). A significant increase in aortic root size at all levels was observed during the follow-up period in all three groups of severity of AR. The rate of change of the supraaortic ridge, the upper support structure of the anulus and cusps, was faster in patients with more severe degrees of AR (p = 0.013); this was not the case at the other aortic levels. No differences were observed in aortic root size or rate of progression between patients with bicuspid or tricuspid aortic valves. Patients were considered "progressive" if they lay on the steepest positive segment of the curve representing the rank order in the rate of aortic root progression. Compared with "nonprogressive" patients, patients who were progressive in supraaortic ridge size (rate >0.12 cm/yr; n = 23) had a faster rate of progression in the degree of regurgitation as assessed by the regurgitant jet area/LV outflow tract area ratio measured in the parasternal short-axis view (0.48 +/- 0.45 vs 0.24 +/- 0.5/yr; p < 0.03) and a foster rate of progression of LV end-diastolic volume (30 +/- 22.8 vs 14.4 +/- 15.6 ml/yr; p < 0.0002) and LV mass (70.8 +/- 74.4 vs 16.8 +/- 19.2 gm/yr; p < 0.0004). In conclusion, there is progressive dilation of the aortic root at all levels, even in patients with mild AR. More rapid progression in aortic root size is associated with more rapid progression of the underlying aortic insufficiency, as well as more rapid increases in LV volume and mass.

Echocardiographic assessment of left ventricular remodeling: are left ventricular diameters suitable tools?

OBJECTIVES: We sought to analyze the value of echocardiographic left ventricular (LV) diameters in assessing LV remodeling. BACKGROUND: LV diameters are easily measured and commonly used as a substitute for volumetric analysis to evaluate LV remodeling caused by ventricular overload or dysfunction. However, the impact of these measurements on outcome is disputed, suggesting that they may not adequately assess LV remodeling. METHODS: M-mode echocardiographically measured LV dimensions and the derived LV ejection fraction and end-systolic wall stress were compared with LV volumes and the derived LV ejection fraction and wall stress using the biplane Simpson rule. These measurements were made prospectively and simultaneously in 463 patients (289 men, 174 women; mean [+/-SD] age 62 +/- 15 years), including 46 normal subjects, 52 with aortic regurgitation, 253 with mitral regurgitation and 112 with LV dysfunction. RESULTS: The correlation between diameter and volume was good at end-systole (r = 0.91, p < 0.0001) and end-diastole (r = 0.86, p < 0.0001). However, the relation was exponential, and the 95% confidence interval increased with increasing diameter. The calculated LV ejection fraction and wall stress using LV diameter and volume correlated linearly with a limited range of error (r = 0.96, SEE = 5%, p < 0.0001 and r = 0.95, SEE = 20 g/cm2, p < 0.0001, respectively). CONCLUSIONS: For assessing LV remodeling, LV diameters measured by M-mode echocardiography allow acceptable estimation of LV ejection fraction and wall stress and correlate significantly with LV volumes but are hindered by a wide range of error for assessment of LV size, especially for enlarged ventricles, suggesting that measurement of LV volume should be the preferred method of echocardiographically assessing LV remodeling.

Right ventricular outflow reconstruction with cryopreserved homografts in pediatric patients: intermediate-term follow-up with serial echocardiographic assessment.

OBJECTIVES: This study was performed to assess by echocardiography the intermediate-term outcome of cryopreserved homografts employed in pulmonary outflow reconstruction in children and to validate the reliability of Doppler echocardiography in their evaluation. BACKGROUND: Cryopreserved homografts have become the most widely used pulmonary conduits. Previous reports have shown the occurrence of homograft regurgitation in the immediate postoperative period and the propensity of regurgitation to progress. Although Doppler echocardiography has been useful in assessing extracardiac valved conduit stenosis, its reliability in assessing a large series of cryopreserved homografts has not been documented. METHODS: Echocardiograms of 41 patients (43 homografts) who underwent operations between December 1986 and October 1992 were retrospectively reviewed. The median age of patients at operation was 37.5 months (range 3 to 333), and the median duration of follow-up was 28.5 months (range 1 to 68). Homograft regurgitation was classified on a scale of 0 to 4+. Pressure gradients across the homografts measured in 23 catheterizations were correlated with corresponding echocardiographic gradients. RESULTS: Regurgitation: Homograft regurgitation occurred in 100% of patients at follow-up. Progression of severity > 2 grades occurred during follow-up in 35% and was associated with operation before age 18 months (p < 0.002) and stenosis progression (p < 0.05) but not with homograft type (aortic or pulmonary). These data predict that 50% of patients operated on before 18 months of age will have severe regurgitation by 15 months postoperatively compared with only 15% operated on after 18 months. Stenosis: At follow-up, 51% of homografts had a stenotic gradient > or = 25 mm Hg predominantly at the distal anastomosis, and stenosis progression was related to young age at operation (< 18 months, p < 0.005) and small conduit size (p < 0.01). Fifty percent of conduits implanted before age 18 months could be predicted to stenose by 21.8 months compared with only 5% of those implanted after age 18 months. The gradient measured from Doppler echocardiography correlated well with the catheterization gradient (r = 0.86). CONCLUSIONS: Cryopreserved homograft dysfunction is frequent and progressive. Young age at operation (< 18 months) predicts more rapid deterioration. Doppler echocardiography is reliable in assessing the systolic gradients across homografts. Serial echocardiographic assessment in the follow-up of these patients accurately characterizes these problems.

General concepts in the morphologic assessment of operatively excised cardiac valves--Part II.

This 2-part article discusses general morphologic assessment of operatively excised cardiac valves and applies these principles to functional classifications. All cardiac valves are categorized into stenotic and purely regurgitant (no element of stenosis) groups based upon structural features: presence or absence of commissural fusion, calcific deposits, and degree and location of fibrosis. Of 2,980 operatively excised cardiac valves reviewed between 1962 and 1992, the most common lesion was aortic stenosis, followed by mitral stenosis and the combination of aortic and mitral stenosis.