The impact of aortic valve replacement (AVR) on the dynamic geometry and motion of the mitral annulus remains unknown. We analyzed the effects of AVR on the dynamic geometry and motion of the mitral annulus. We used 3-dimensional transesophageal echocardiography to analyze 39 consecutive patients undergoing elective surgical AVR for aortic stenosis. Intraoperative 3-dimensional transesophageal echocardiography was performed immediately before and after AVR. Volumetric data sets were analyzed using a software package capable of dynamically tracking the mitral annulus and leaflets during the entire systolic ejection phase. After AVR, there were significant decreases (p <0.01) in annular dimensions such as anteroposterior (3.5 ± 0.1 vs 3.2 ± 0.1 cm), anterolateral-posteromedial (3.7 ± 0.1 vs 3.5 ± 0.1 cm), and commissural diameters (3.7 ± 0.1 vs 3.3 ± 0.1 cm), as well as annular circumference (12.0 ± 0.30 vs 11.1 ± 0.2 cm) and 3-dimensional mitral annular area (mean 10.9 ± 0.6 vs 9.3 ± 0.3 cm(3)). Vertical mitral annular displacement was also reduced (6.2 ± 3.1 vs 4.3 ± 2.2 mm). Mitral annular nonplanarity angle (154 ± 1.5° vs 161 ± 1.6°) and aorto-mitral angle (133 ± 3.3° vs 142 ± 2.0°) were both increased after AVR, suggesting reduced nonplanar shape of the mitral annulus and reduced aorto-mitral flexion. In conclusion, these data demonstrate that mitral annular size is reduced immediately after AVR and that the dynamic motion of the mitral annulus is restricted. These findings may have important clinical implications for patients undergoing AVR with concurrent mitral regurgitation.
BACKGROUND: Owing to its elliptical shape, the left ventricle outflow tract (LVOT) area is underestimated by two-dimensional (2D) diameter-based calculations which assume a circular shape. This results in overestimation of aortic stenosis (AS) by the continuity equation. In cases of moderate to severe AS, this overestimation can affect intraoperative clinical decision making (expectant management versus replacement). The purpose of this intraoperative study was to compare the aortic valve area calculated by 2D diameter based and three-dimensional (3D) derived LVOT area via transesophageal echocardiography (TEE) and its impact on severity of AS.
METHODS: The LVOT area was calculated using intraoperative 2D and 3D TEE data from patients undergoing aortic valve replacement (AVR) and coronary artery bypass graft (CABG) surgery using the 2D diameter (RADIUS), 3D planimetry (PLANE), and 3D biplane (π·x·y) measurement (ELLIPSE) methods. For each method, the LVOT area was used to determine the aortic valve area by the continuity equation and the severity of AS categorized as mild, moderate, or severe.
RESULTS: A total of 66 patients completed the study. The RADIUS method (3.5 ± 0.9 cm(2)) underestimated LVOT area by 21% (p < 0.05) compared with the PLANE method (4.1 ± 0.1 cm(2)) and by 18% (p < 0.05) compared with the ELLIPSE method (4.0 ± 0.9 cm(2)). There was no significant difference between the two 3D methods, namely, PLANE and ELLIPSE. Seven AVR patients (18%) and 1 CABG surgery patient (6%) who had originally been classified as severe AS by the 2D method were reclassified as moderate AS by the 3D methods (p < 0.001).
CONCLUSIONS: Three-dimensional echocardiography has the potential to impact surgical decision making in cases of moderate to severe AS.
While the angiogenic effects of Neuropeptide Y (NPY) in myocardial ischemia and hypercholesterolemia have been studied, its effects on altering oxidative stress, fibrosis and cell death are not known. We hypothesized that local infiltration of NPY in a swine model of chronic myocardial ischemia and hypercholesterolemia will induce nerve growth and cell survival, while reducing oxidative stress and fibrosis. Yorkshire mini-swine (n=15) were fed a high cholesterol diet for 5 weeks. Three weeks after surgical induction of focal myocardial ischemia, an osmotic pump was implanted, which delivered NPY (n=8, high cholesterol treated, HCT) or the vehicle (n=7, high cholesterol control, HCC) for 5 weeks. Then myocardium was harvested for analysis. Assessment of myocardial function and perfusion was made the last intervention. Immunoblotting demonstrated significantly decreased levels of MMP-9 (p=0.001) and TGF-β (p=0.05) and significantly increased levels of Ang-1 (p=0.002), MnSOD (p=0.006) and NGF (p=0.01) in HCT. Immunohistochemistry results revealed significantly decreased TUNEL staining (p=0.005) and GLUT4 translocation (p=0.004) in HCT. The functional data showed significantly improved blood flow reserve (p=0.02) and improved diastolic function -dP/dt (p=0.009) in the treated animals. Local infiltration of NPY results in positive remodeling in ischemic myocardium in the setting of hypercholesterolemia. By initiating angio and neurogenesis, NPY infiltration improves blood flow reserve and restoration of fatty acid metabolism. The associated increased cell survival and decreased fibrosis result in improved myocardial diastolic function. NPY may have a potential therapeutic role in patients with hypercholesterolemia associated coronary artery disease.
While percutaneous intervention is an alternative for patients who are not surgical candidates, the rate of morbidity and mortality is comparable to open repair. Appending the reported complications associated with percutaneous intervention (device mal-positioning, dislodgement, and entrapment in the sub-valvular apparatus), we report mechanical damage to the tricuspid valve (TV). Percutaneous closure with an Amplatzer septal occluder device was attempted on three patients who developed a ventricular septal defects (VSD) after myocardial infarction. In all three cases, damage to the tricuspid leaflet was noted post-procedure. The accompanying severe tricuspid regurgitation led to right ventricular failure, even in the patients where the VSD was considered successfully occluded. Despite successful deployment of the Amplatzer device, complications with catheter manipulation may still arise. Damage to the TV can occur during percutaneous VSD closure with Amplatzer device. Periprocedure TEE monitoring can detect damage to the tricuspid leaflets.
With the resurgence in popularity of aortic valve (AV) repair, detailed anatomical information of the AV has become invaluable for surgical decision making as well as for evaluation of success postrepair. Perioperative 3-dimensional echocardiography is optimally suited to assist in repair planning. The volumetric nature of the 3-dimensional data allows accurate derivation of qualitative and quantitative measurements. A uniform approach to imaging and description of echocardiographic AV anatomy is essential to facilitate communication across specialties.
OBJECTIVE: To demonstrate the clinical feasibility of accurately measuring tricuspid annular area by 3-dimensional (3D) transesophageal echocardiography (TEE) and to assess the geometric differences based on the presence of tricuspid regurgitation (TR). Also, the shape of the tricuspid annulus was compared with previous descriptions in the literature.
SETTING: Tertiary care university hospital.
INTERVENTIONS: Three-dimensional TEE.
PARTICIPANTS: Patients undergoing cardiac surgery.
MEASUREMENTS AND MAIN RESULTS: Volumetric data sets from 20 patients were acquired by 3D TEE and prospectively analyzed. Comparisons in annular geometry were made between groups based on the presence of TR. The QLab (Philips Medical Systems, Andover, MA) software package was used to calculate tricuspid annular area by both linear elliptical dimensions and planimetry. Further analyses were performed in the 4D Cardio-View (TomTec Corporation GmBH, Munich, Germany) and MATLAB (Natick, MA) software environments to accurately assess annular shape. It was found that patients with greater TR had an eccentrically dilated annulus with a larger annular area. Also, the area as measured by the linear ellipse method was overestimated as compared to the planimetry method. Furthermore, the irregular saddle-shaped geometry of the tricuspid annulus was confirmed through the mathematic model developed by the authors.
CONCLUSIONS: Three-dimensional TEE can be used to measure the tricuspid annular area in a clinically feasible fashion, with an eccentric dilation seen in patients with TR. The tricuspid annulus shape is complex, with annular high and low points, and annular area calculation based on linear measurements significantly overestimates 3D planimetered area.
OBJECTIVE: To compare two methods of mitral annular nonplanarity: the mathematically calculated annular height-to-commissural width ratio (AHCWR) and the echocardiographically derived nonplanarity angle.
SETTING: Tertiary care university hospital.
INTERVENTIONS: Three-dimensional transesophageal echocardiography.
PARTICIPANTS: Patients undergoing mitral valve surgery.
MEASUREMENTS AND MAIN RESULTS: Using 3-dimensional transesophageal echocardiography, volumetric datasets were acquired from 22 patients undergoing mitral valve surgery. The intraoperative nonplanarity angle was calculated with Mitral Valve Assessment software (Tomtec GmbH, Munich, Germany). Furthermore, the datasets acquired during 3-dimensional transesophageal echocardiography were exported to Matlab software (MathWorks, Natick, MA), which was used to calculate the AHCWR. The nonplanarity angle was seen to correlate favorably with the AHCWR (r = 0.70).
CONCLUSIONS: A favorable correlation was found between the nonplanarity angle and the AHCWR. This suggests that the nonplanarity angle can be used to assess mitral annular nonplanarity in a clinically feasible fashion.
OBJECTIVES: To investigate the effects of acute elevation in afterload on global (systolic and diastolic) myocardial function by performing serial intraoperative transesophageal echocardiograms during and after cross-clamp application on patients undergoing elective abdominal aortic aneurysm (AAA) surgery.
DESIGN: A prospective observational study.
SETTING: A tertiary care university hospital.
PARTICIPANTS: Patients undergoing elective AAA repair under general anesthesia (GA).
INTERVENTION: The use of perioperative transesophageal echocardiography to calculate a tissue Doppler-derived myocardial performance index (MPI) during different stages of the surgery.
MEASUREMENT AND RESULTS: Twenty consecutive patients scheduled for suprarenal AAA repair under GA were included in the study. Perioperative transesophageal echocardiography was performed after the induction of GA. MPI was calculated with Doppler tissue imaging as the sum of isovolumetric contraction and relaxation times divided by the ejection time before cross-clamping of the aorta and then 2, 10, and 20 minutes after cross-clamp application. A final MPI was measured after unclamping of the aorta. As compared with baseline, cross-clamp application initially worsened MPI within 2 minutes and then MPI improved to baseline after 10 minutes of cross-clamp application. The MPI improved significantly after unclamping of the aorta.
CONCLUSIONS: The authors observed a temporal variation in global myocardial function after the application of a cross-clamp in the suprarenal position. There was transient deterioration of global myocardial function (the prolongation of MPI) 2 minutes after cross-clamp application, which improved within 10 minutes. Myocardial function returned to baseline after unclamping the aorta.
BACKGROUND: Preoperative increased pulse pressure (PP) has been found to be a predictor of major adverse cardiovascular events (MACEs) after coronary artery bypass graft surgery. In this study, we evaluated the predictive ability of increased preoperative PP to identify MACEs in patients with peripheral vascular disease undergoing lower extremity vascular bypass surgery.
METHODS: We used the prospectively collected vascular surgery database at our institution to identify 412 consecutive patients who had lower extremity bypass surgery between January 2003 and December 2004. Preoperative demographics including comorbidities, medications, intraoperative characteristics, and postoperative MACE outcomes (myocardial infarction, congestive heart failure, stroke, and in-hospital mortality) were recorded. PP data as a continuous and categorical variable (PP <80 or ≥80 mm Hg) were tested for the ability to predict postoperative MACEs. A final parsimonious logistic regression was built to evaluate the predictive ability of PP.
RESULTS: MACEs occurred in 5.7% of patients in the PP <80 mm Hg group compared with 8.8% in the PP ≥80 mm Hg group (P = 0.229). Patients with MACEs were older (76 ± 10 years vs 68 ± 12 years; P = 0.001), had a history of myocardial infarction (9% vs 4%; P = 0.049), and had a preoperative PP of 75 ± 19 mm Hg vs 71 ± 21 mm Hg (P = 0.306). In the final logistic regression model, only age in years was a predictor of MACEs (odds ratio, 1.062; 95% confidence interval, 1.02-1.10; P = 0.02). There was no relationship between PP ≥80 mm Hg and risk for MACEs (odds ratio, 1.36; 95% confidence interval, 0.62-2.90; P = 0.44).
CONCLUSIONS: Preoperative increase in PP is not a predictor of adverse cardiovascular outcomes in patients having lower extremity revascularization surgery.
BACKGROUND: Non-cardiac findings (NCFs) are seen in more than a third of cardiac computed tomographic and cardiac magnetic resonance imaging studies. The prevalence and importance of NCFs in transthoracic echocardiographic (TTE) imaging is unknown. The aim of this study was to determine the prevalence of NCFs on TTE imaging.
METHODS: The subcostal images of all comprehensive adult TTE studies performed at one institution in December 2008 were retrospectively reviewed for NCFs by a radiologist with fellowship training in cardiovascular and abdominal radiology and blinded to the TTE report findings and clinical histories. Additional TTE image orientations were assessed in a subset of 300 studies. NCFs were categorized as benign (e.g., simple hepatic cyst), indeterminate (e.g., ascites), or worrisome (e.g., liver metastases). If an indeterminate or worrisome NCF was identified, the patient's electronic medical record was reviewed to determine if the NCF was previously known.
RESULTS: Of 1,008 TTE studies (443 inpatient, 565 outpatient) in 922 patients, 77 NCFs were identified in 69 patients (7.5%). These included 20 benign (26%), 52 indeterminate (67%), and five worrisome (7%) NCFs. Intermediate and worrisome NCFs were more common in inpatient TTE studies (9% vs 3% outpatient, P = .002). The additional views demonstrated 2% more NCFs. Record review demonstrated that 60% of worrisome and 67% of indeterminate NCFs were previously known. No unknown NCF ultimately led to a change in patient management.
CONCLUSIONS: Clinical TTE studies demonstrate NCFs in 7.5% of all patients, with an increased prevalence on inpatient studies. Although 75% of NCFs were potentially management changing, the majority of these were previously known and very unlikely to lead to management changes. Further study is needed to validate these findings in other populations and to assess their clinical impact.