Abstract 1589: Pulmonary Hypertension Is Associated With Regional Right Ventricular Systolic Dysfunction And Dyssynchrony: Strain and Strain Rate Assessment Using Velocity Vector Imaging Technique.
Background: Strain and strain rate has been shown to identify subtle contraction abnormalities of left ventricle. Objectives: We hypothesized that S and SR derived from velocity vector imaging (VVI) will allow early identification of global and regional RV systolic function in patients with pulmonary hypertension (PHT) compared to conventional echo parameters. Methods: 96 patients, 35 normal RV Systolic Pressure (RVSP < 30 mmHg) and 61 with PHT, {24 mild-moderate (RVSP > 60 mmHg) and 37 severe (RVSP < 60 mmHg)} underwent echo-Doppler assessment of RV. Apical 4 chamber images at end expiration were used for RV lateral wall (LW) and ventricular septal (VS) segment analysis for systolic tangential velocity (Ta V), S and SR. In addition RV end systolic and diastolic area, RV fractional area change (RV FAC), RV performance index (RIMP) and tricuspid annulus systolic excursion were measured. Results: Peak S, systolic SR and Ta V at the basal, mid and apical segments of the RV LW and VS were depressed in patients with PHT compared with controls, Table 1 , P 0.001. Similarly, significant decrease in RIMP was seen in patients with PHT compared to controls, p <0.001. Significant correlation (p<0.001, r >0.6) was noted between the 2D FAC and S, SR. The time to peak systolic S indexed to end diastolic area (EDA) is significantly prolonged, p<0.01 in all segments in patients with PHT indicating dyssynchrony. Conclusion: S and SR allows assesment of Regional RV systolic function otherwise difficult to assess from conventional echo-Doppler technique. PHTN is associated with not only regional RV systolic dysfunction but also with dyssynchrony. Thus, this new tool can offer new insights in the functioning of right ventricular global and regional function. mean±SD of strain
Right and left ventricular interaction in pulmonary hypertension: Insight from velocity vector imaging
ObjectiveTo evaluate whether global peak systolic strain (PSS) and peak systolic strain rate (PSSR) derived from velocity vector imaging (VVI) allow early recognition of regional and global right ventricular (RV) dysfunction and the impact of this on left ventricular (LV) function in patients with pulmonary hypertension (PHT).BackgroundRV function is an important determinant of prognosis in patients with heart failure, pulmonary hypertension, heart transplant, and congenital heart diseases. However, evaluation of the right ventricle is often limited by its complex geometry and inadequate visualization of RV free wall. Furthermore, the impact of RV dysfunction on the LV function is not well elucidated.MethodsNinety‐nine participants, 35 control patients with normal RV systolic pressure (RVSP) (<30 mm Hg) and 64 patients with PHT (25 with mild‐to‐moderate increase in RVSP [≥36 and <60 mm Hg] and 39 with severe increase in RVSP [≥60 mm Hg]), underwent comprehensive echo‐Doppler assessment and velocity vector imaging (VVI) for strain rate analysis. RV regional peak systolic and diastolic tangential velocity, strain, and strain rate were obtained from the basal, mid and apical segments of the RV free wall and interventricular septum (IVS) from apical 4‐chamber view at end‐expiration. Similar data were obtained from eighteen LV segments from apical 4‐chamber, 2‐chamber, and long‐axis views.ResultsPeak systolic strain, strain rate, and tangential velocity at all segments in the RV free wall and IVS were decreased compared to controls in patients with PHT (P < 0.001). Significant correlation (r > 0.60; P < 0.001) was noted between RVSP and systolic and diastolic strain and strain rate at basal segment in IVS and global RV function. Peak early diastolic strain rate at all segments was also decreased in PHT patients compared with control patients (P < 0.01). Furthermore, RV systolic and diastolic strain and strain rate were lower in group 2 with mild‐to‐moderate hypertension while the conventional echo parameters were normal. Except for IVS segments, other LV segments had no statistical differences in systolic and diastolic velocity, strain, and strain rate compared to controls. However, they were lower than the published normal range.ConclusionsStrain and strain rate derived from VVI demonstrates early recognition of systolic and diastolic RV dysfunction in patients with PHT compared to controls. PHT is associated with global and regional RV systolic and diastolic dysfunction. Systolic and diastolic strain and strain rate from LV was lower compared to controls but were not statistically significant. This may indicate subclinical LV dysfunction in these patients, suggesting that conventional LV function parameters may not be sensitive to recognize subclinical LV dysfunction.
Exercise-Echocardiography-Derived Pulmonary Artery Pressure Slope in Borderline and Mild to Moderate Pulmonary Arterial Hypertension
Background: Prophylactic exclusion of the left atrial appendage (LAA) is often performed during cardiac surgery ostensibly to reduce the risk of stroke. However, the clinical impact of LAA closure in humans remains inconclusive. Methods: Of 10 633 adults who underwent coronary artery bypass grafting and valve surgery between January 2000 and December 2005, 9792 patients with complete baseline characteristics, surgery procedure, and follow-up data were included in this analysis. A propensity score–matching analysis based on 28 pretreatment covariates was performed and 461 matching pairs were derived and analyzed to estimate the association of LAA closure with early postoperative atrial fibrillation (POAF) (atrial fibrillation ≤30 days of surgery), ischemic stroke, and mortality. Results: In the propensity-matched cohort, the overall incidence of POAF was 53.9%. In this group, the rate of early POAF among the patients who underwent LAA closure was 68.6% versus 31.9% for those who did not undergo the procedure ( P <0.001). LAA closure was independently associated with an increased risk of early POAF (adjusted odds ratio, 3.88; 95% confidence interval, 2.89–5.20), but did not significantly influence the risk of stroke (adjusted hazard ratio, 1.07; 95% confidence interval, 0.72–1.58) or mortality (adjusted hazard ratio, 0.92; 95% confidence interval, 0.75–1.13). Conclusions: After adjustment for treatment allocation bias, LAA closure during routine cardiac surgery was significantly associated with an increased risk of early POAF, but it did not influence the risk of stroke or mortality. It remains uncertain whether prophylactic exclusion of the LAA is warranted for stroke prevention during non–atrial fibrillation-related cardiac surgery.
Ia Diastolic Dysfunction: An Echocardiographic Grade
ObjectiveTo demonstrate that a distinct group of patients with Grade Ia diastolic dysfunction who do not conform to present ASE/ESE diastolic grading exists.Method and ResultsEchocardiographic and demographic data of the Grade Ia diastolic dysfunction were extracted and compared with that of Grades I and II in 515 patients. The mean of age of the cohort was 75 ± 9 years and body mass index did not differ significantly between the 3 groups (P = 0.45). Measurements of left atrial volume index (28.58 ± 7 mL/m2 in I, 33 ± 10 mL/m2 in Ia, and 39 ± 12 mL/m2 in II P < 0.001), isovolumic relaxation time (IVRT) (100 ± 17 msec in I, 103 ± 21 msec in Ia, and 79 ± 15 msec in II P < 0.001), deceleration time (248 ± 52 msec in I, 263 ± 58 msec in Ia, and 217 ± 57 msec in II P < 0.001), medial E/e′ (10 ± 3 in I, 18 ± 5.00 in Ia, and 22 ± 8 in II), and lateral E/e′ (8 ± 3 in I, 15 ± 6 in Ia, and 18 ± 9 in II P < 0.001) were significantly different in grade Ia compared with I and II. These findings remained significant even after adjusting for age, gender, diabetes, and smoking.ConclusionPatients with echocardiographic characteristics of relaxation abnormality (E/A ratio of <0.8) and elevated filling pressures (septal E/e′ ≥15, lateral E/e′ ≥12, average E/e′ ≥13) should be graded as a separate Grade Ia group.
Calcific Constrictive Pericarditis: Is It Still with Us?
Background —Atrial septal aneurysm (ASA) is a putative risk factor for cardioembolism. However, the frequency of ASA in the general population has not been adequately determined. Therefore, the frequency in patients with cerebral ischemic events, compared with the frequency in the general population, is poorly defined. We sought to determine the frequency of ASA in the general population and to compare the frequency of ASA in patients with cerebral ischemic events with the frequency in the general population. Methods and Results —The frequency of ASA in the population was determined in 363 subjects, a sample of the participants in the Stroke Prevention: Assessment of Risk in a Community study (control subjects), and was compared with the frequency in 355 age- and sex-matched patients undergoing transesophageal echocardiography in search of a cardiac source of embolism after a focal cerebral ischemic event. The proportion with ASA was 7.9% in patients versus 2.2% in control subjects ( P =0.002; odds ratio of ASA, 3.65; 95% CI, 1.64 to 8.13, in patients versus control subjects). Patent foramen ovale (PFO) was detected with contrast injections in 56% of subjects with ASA. The presence of ASA predicted the presence of PFO (odds ratio of PFO, 4.57; 95% CI, 2.18 to 9.57, in subjects with versus those without ASA). In 86% of subjects with ASA and cerebral ischemia, transesophageal echocardiography did not detect an alternative source of cardioembolism other than an associated PFO. Conclusions —The prevalence of ASA based on this population-based study is 2.2%. The frequency of ASA is relatively higher in patients evaluated with transesophageal echocardiography after a cerebral ischemic event. ASA is frequently associated with PFO, suggesting paradoxical embolism as a mechanism of cardioembolism. In patients with cerebral ischemia and ASA, ASA (with or without PFO) commonly is the only potential cardioembolic source detected with transesophageal echocardiography.
Assessment of Severity of Aortic Regurgitation Using the Width of the Vena Contracta
Background —The width of the vena contracta (VC-W), the smallest area of regurgitant flow, reflects the degree of valvular regurgitation and is measurable by color Doppler imaging, but this method has not been validated in aortic regurgitation (AR). Methods and Results —We prospectively examined 79 patients with isolated AR and 80 patients without regurgitation. The VC-W was measured from the long-axis parasternal view and compared with 2 simultaneous reference methods (quantitative Doppler and 2D echocardiography). In patients without regurgitation, the agreement between methods was excellent. In patients with AR, good correlations (all P <0.0001) were obtained between VC-W and effective regurgitant orifice (ERO) area and regurgitant volume recorded by quantitative Doppler ( r =0.89 and 0.90, respectively) and 2D echocardiographic ( r =0.90 and 0.89, respectively) methods. These correlations were similar with eccentric or central jets (all P >0.60). The other methods used showed good correlations of VC-W with aortographic grading of AR (n=8, r =0.82, P =0.01), with the proximal flow convergence method (n=53, r =0.85, P <0.0001), and with left ventricular end-diastolic volume ( r =0.81, P <0.0001). Sensitivity and specificity of VC-W ≥6 mm for diagnosing severe AR (ERO ≥30 mm 2 ) were 95% and 90%, respectively. Conclusions —For assessment of the degree of AR, VC-W shows good correlations with simultaneous quantitative measures (regardless of jet direction), shows good correlations with other methods of assessment of AR, and provides a high diagnostic value for severe AR. VC-W is a simple, reliable method that can be used clinically as part of comprehensive Doppler echocardiographic assessment of AR.
Effects of Sildenafil Citrate (Viagra) Combined With Nitrate on the Heart
Background—Sildenafil citrate (Viagra) is indicated for the treatment of erectile dysfunction. Large and sudden decreases in systemic blood pressure were reported in a substantial number of patients taking sildenafil citrate combined with nitroglycerin. We studied the effect of sildenafil citrate on the relationship between changes in systemic blood pressure and coronary blood flow.Methods and Results—Healthy male beagles were used to assess systemic blood pressure, pulmonary arterial pressure, and flow in the left circumflex artery (in which a critical stenosis was established) and left anterior descending coronary artery. After measurement of the hemodynamic variables, 2 mg/kg sildenafil citrate was administered via a nasogastric tube. Hemodynamic changes were monitored for 1 hour. Subsequently, the acute effect of nitrate combined with sildenafil citrate was studied by the bolus injection of 0.2 mg isosorbide dinitrate before and after sildenafil citrate. Systemic blood and pulmonary arterial pressures and circumflex flow did not change during this study; however, left anterior descending coronary arterial flow increased from 16.0±5.8 to 24.6±8.7 mL/min 1 hour after administration of sildenafil citrate. The prolongation of systemic blood pressure decrease and the circumflex flow decrement induced by isosorbide dinitrate after sildenafil citrate were significantly larger and longer than those before sildenafil citrate.Conclusions—Sildenafil citrate had the effect of vasodilation in a normal coronary artery; however, a combined effect with nitrate resulted in large and protracted decreases in systemic blood pressure and coronary blood flow in vessels with critical stenosis.