Pressure Half-time Method Research Articles

Does chronic mitral regurgitation influence Doppler pressure half-time–derived calculation of the mitral valve area in patients with mitral stenosis?

Background In patients with mitral stenosis (MS), Doppler pressure half-time (PHT) may be influenced by hemodynamic variables other than the anatomic mitral valve orifice narrowing. This study was undertaken to assess whether the presence of concomitant mitral regurgitation (MR) affects mitral valve area (MVA) estimation by PHT. Methods Consecutive patients (n = 166) with noncalcific MS, in sinus rhythm, were studied. Group 1 (n = 106) had no or mild MR, and group 2 (n = 60) had moderate or severe MR. MVA was assessed by using the PHT method and planimetry. Results There was a strong correlation between planimetry and PHT MVA in both groups (group 1: r = 0.86, P < .001; group 2: r = 0.73, P < .001). However, compared with planimetry MVA, PHT underestimated MVA by ≥20% in 18 patients (17%) in group 1 and 21 patients (35%) in group 2 ( P < .01). Overestimation by ≥20% occurred in 12 patients (11%) in group 1 and in 7 (12%) in group 2. Group 2 subanalysis (group 2A: moderate MR, n = 16; group 2B: severe MR, n = 44) revealed that linear regression weakened with increasing severity of MR (group 2A: r = 0.824, P < .001, group 2B: r = 0.70, P < .001). PHT underestimation of MVA occurred in 31% and 36% of patients in Groups IIA and IIB, respectively ( P = NS). Conclusions PHT appears to be reliable for estimating MVA in most patients with MS, even in the presence of MR. However, the presence of significant MR reduces the reliability of PHT-derived MVA, with underestimation of MVA in a significant number of subjects. The severity of MR has a direct impact on PHT-derived MVA.

Quantification of stenotic mitral valve area with magnetic resonance imaging and comparison with Doppler ultrasound

ObjectivesThe purpose of this study was to evaluate the reliability of the pressure half-time (PHT) method for estimating mitral valve areas (MVAs) by velocity-encoded cardiovascular magnetic resonance (VE-CMR) and to compare the method with paired Doppler ultrasound. BackgroundThe pressure half-time Doppler echocardiography method is a practical technique for clinical evaluation of mitral stenosis. As CMR continues evolving as a routine clinical tool, its use for estimating MVA requires thorough evaluation. MethodsSeventeen patients with mitral stenosis underwent echocardiography and CMR. Using VE-CMR, MVA was estimated by PHT method. Additionally, peak E and peak A velocities were defined. Interobserver repeatability of VE-CMR was evaluated. ResultsBy Doppler, MVAs ranged from 0.87 to 4.49 cm2; by CMR, 0.91 to 2.70 cm2, correlating well between modalities (r = 0.86). The correlation coefficient for peak E and peak A between modalities was 0.81 and 0.89, respectively. Velocity-encoded CMR data analysis provided robust, repeatable estimates of peak E, peak A, and MVA (r = 0.99, 0.99, and 0.96, respectively). ConclusionsVelocity-encoded cardiovascular magnetic resonance can be used routinely as a robust tool to quantify MVA via mitral flow velocity analysis with PHT method.

Increased Plasma Levels of Soluble P-Selectin in Rheumatic Mitral Stenosis

<h3>Background:</h3> Previous studies have demonstrated that platelet activation occurs in peripheral blood of patients with rheumatic mitral stenosis (MS). However, in patients with MS, the plasma level of soluble P-selectin (a marker of platelet activation) remains unsettled. <h3>Methods and results:</h3> A total of 20 patients with symptomatic MS undergoing percutaneous transluminal mitral valvuloplasty (PTMV) were studied (group 1; 16 patients in permanent atrial fibrillation, and 4 patients in sinus rhythm). The plasma levels of soluble P-selectin in the femoral vein and artery, and right and left atria before PTMV and those in the peripheral venous blood at the 1-week and 4-week follow-ups after PTMV were determined by solid-phase, sandwich, enzyme-linked immunosorbent assay. The mitral valve area was calculated by means of the Doppler pressure half-time method. In addition, we measured plasma concentrations of soluble P-selectin in the peripheral venous blood samples obtained from 22 control patients (including 14 healthy volunteers in sinus rhythm [group 2] and 8 patients in permanent lone atrial fibrillation [group 3]). The plasma levels of soluble P-selectin were significantly elevated in group 1 patients (49.78 ± 37.72 ng/mL) [mean ± SD] compared with group 2 (25.52 ± 15.38 ng/mL) and group 3 patients (32.17 ± 14.18 ng/mL) [p < 0.005]. In group 1 patients, the plasma levels of soluble P-selectin in the left atrium did not significantly differ from those in the right atrium, femoral vein, or femoral artery (p = 0.05). The area of mitral valve increased significantly after PTMV (1.06 ± 0.17 cm² vs 1.48 ± 0.32 cm², p < 0.0001). The mean left atrial pressure fell significantly and immediately after PTMV (23.0 ± 5.1 mm Hg vs 17.6 ± 5.9 mm Hg, p < 0.0001). The peripheral venous plasma levels of soluble P-selectin obtained before PTMV did not significantly fall after PTMV (before, 49.8 ± 37.7 ng/mL; 10 min after, 39.8 ± 19.1 ng/mL; 1 week after, 46.1 ± 20.8 ng/mL; and 4 weeks after, 41.2 ± 15.9 ng/mL; p=0.145). <h3>Conclusions:</h3> The venous plasma levels of soluble P-selectin in patients with moderate-to-severe MS were significantly higher than those in healthy volunteers or patients with lone atrial fibrillation. In addition, in patients with MS, there was no difference in the plasma levels of soluble P-selectin between the left and right atrial blood and between peripheral and atrial blood. Moreover, there was no change in soluble P-selectin levels as a result of PTMV.

Mechanism of Reducing Platelet Activity by Percutaneous Transluminal Mitral Valvuloplasty in Patients With Rheumatic Mitral Stenosis

Previous studies have demonstrated that platelet activity significantly decreased after optimal percutaneous transluminal mitral valvuloplasty (PTMV) in patients with rheumatic mitral stenosis (MS). However, the mechanism of reducing platelet activity by valvuloplasty remains unclear. We studied 19 patients with symptomatic MS who were undergoing PTMV. The fractions of unstimulated platelets expressing P-selectin in the venous blood obtained before, and at the 1-week and 4-week follow-ups after PTMV were determined by flow cytometry. The mitral valve areas, measured before and at the 1-week follow-up after PTMV, were calculated by means of the Doppler pressure half-time method. The mean (+/- SD) area of the mitral valve increased significantly after PTMV (1.05 +/- 0.17 vs 1.44 +/- 0.27 cm2, respectively; p < 0.0001). The mean left atrial area was reduced in size significantly after PTMV (36.6 +/- 11.4 vs 33.9 +/- 13.4 cm2, respectively; p < 0.05). The mean left atrial pressure (23.3 +/- 5.1 vs 18.0 +/- 5.8 mm Hg, respectively; p < 0.0001) and the mean pulmonary arterial pressure (31.4 +/- 7.8 vs 26.1 +/- 7.7 mm Hg, respectively; p < 0.0001) fell significantly after PTMV. The fraction of platelets expressing P-selectin in the venous blood fell significantly after PTMV (before PTMV, 4.7 +/- 2.4%; 1 week after PTMV, 2.2 +/- 2.1%; 4 weeks after PTMV, 2.0 +/- 1.7%; p < 0.0001). Correlation analysis demonstrated that there was a significantly direct relationship between the magnitude of increase in mitral valve area and the magnitude of decrease in the fraction of platelets expressing P-selectin in the venous blood 4 weeks after PTMV (p = 0.0013; r = 0.682). However, there was no significant correlation between the magnitude of decrease in the fraction of platelets expressing P-selectin in the venous blood and the magnitude of decrease in the left atrial area, the decrease in left atrial pressure, or the decrease in the pulmonary artery pressure after PTMV. In patients with moderate-to-severe MS, increased platelet activation fell significantly after PTMV. It was the increase in mitral valve area by PTMV, instead of hemodynamic and echocardiographic factors, that accounted for the decrease in the fraction of venous platelets expressing P-selectin after PTMV.

Percutaneous Transluminal Mitral Valvuloplasty Reduces Circulating Vascular Cell Adhesion Molecule-1 in Rheumatic Mitral Stenosis

The circulating levels of adhesion molecules, such as vascular cell adhesion molecule-1 (VCAM-1) and intercellular adhesion molecule-1 (ICAM-1), have been demonstrated to be elevated in patients with rheumatic mitral stenosis (MS). However, the impact of percutaneous transluminal mitral valvuloplasty (PTMV) on the elevated circulating levels of VCAM-1 and ICAM-1 in patients with MS has never been investigated. and results: A total of 19 patients with symptomatic MS undergoing PTMV were studied (group 1) [15 patients in chronic atrial fibrillation, and 4 patients in sinus rhythm]. The plasma levels of soluble VCAM-1 and ICAM-1 in the femoral vein and artery, and right and left atria before PTMV, and those in the peripheral venous blood at the 1-week and 4-week follow-ups after PTMV were determined by solid-phase sandwich enzyme-linked immunosorbent assay. The mitral valve area was calculated by means of the Doppler pressure half-time method. In addition, we measured plasma concentrations of soluble VCAM-1 and ICAM-1 in the peripheral venous blood samples obtained from 22 control patients (including 14 healthy volunteers in sinus rhythm [group 2] and 8 patients in chronic lone atrial fibrillation [group 3]). The plasma level of soluble VCAM-1 was significantly elevated in group 1 patients (1,205.4 +/- 462.4 ng/mL [mean +/- SD]) compared with group 2 (580.9 +/- 208.0 ng/mL) and group 3 patients (716.4 +/- 221.6 ng/mL) [p < 0.0001]. In group 1 patients, the plasma levels of soluble VCAM-1 and ICAM-1 in the left atrium did not differ from those in the right atrium, femoral vein, or femoral artery (p = 0.668 for VCAM-1, and p = 0.232 for ICAM-1). The area of mitral valve increased significantly after PTMV (1.08 +/- 0.14 cm(2) vs 1.48 +/- 0.33 cm(2), p < 0.0001). The mean left atrial pressure fell significantly after PTMV (22.9 +/- 5.2 mm Hg vs 17.7 +/- 6.0 mm Hg, p < 0.0001). The peripheral venous plasma level of soluble VCAM-1 obtained before PTMV fell significantly after PTMV (before, 1,205.4 +/- 462.4 ng/mL; 1 week after PTMV, 915.7 +/- 280.2 ng/mL; 4 weeks after PTMV, 859.0 +/- 298.7 ng/mL; p < 0.0001). In patients with moderate-to-severe MS, the venous plasma level of soluble VCAM-1 fell significantly after PTMV, and the elevated plasma soluble VCAM-1 concentration was associated with hemodynamic abnormality rather than with rheumatic activity.

Echocardiographic assessment of left and right heart hemodynamics in a patient with lutembacher's syndrome

We present a case of a 53-year-old woman with intractable shortness of breath that was originally ascribed to bronchiolitis obliterans organizing pneumonia. Subsequently evaluation by echocardiography and cardiac catheterization revealed that she had Lutembacher's syndrome, an uncommon combination of congenital atrial septal defect (ASD) and acquired mitral stenosis that is difficult to diagnose clinically. Our case illustrates the pitfalls and advantages of echocardiographic assessment of the mitral valve area (MVA) and the left atrial pressure (LAP). The pressure half-time method used most commonly for estimating MVA echocardiographically is inaccurate and may lead to underestimation of the severity of mitral stenosis in patients with Lutembacher's syndrome. On the other hand, the presence of ASD provides an additional method of calculating LAP, the most important determinant of symptoms in patients with mitral stenosis.

Clinical Applicability for the Assessment of the Valvular Mitral Stenosis Severity with Doppler Echocardiography and the Proximal Isovelocity Surface Area (PISA) Method

Evaluation of the severity of valvular mitral stenosis and measurements of the effective rheumatic mitral valve area by noninvasive echocardiography has been well accepted. The area is measured by the two-dimensional planimetry (PLM) method and the Doppler pressure half-time (PHT) method. Recently, the proximal isovelocity surface area (PISA) by color Doppler technique has been used as a quantitative measurement for valvular heart disease. However, this method needs more validation. The aim of this study was therefore to investigate the clinical applicability of the PISA method in the measurements of effective mitral valve area in patients with rheumatic valvular heart disease. Forty-seven patients aged from 23 to 71 years, with a mean age of 53 +/- 13 (25 male and 22 female, 15 with sinus rhythm, mean heart rate of 83 +/- 14 beats per minute, with rheumatic valvular mitral stenosis without hemodynamically significant mitral regurgitation) were included in the study. Effective mitral valve area (MVA) derived by the PISA method was calculated as follows: 2 x Pi x (proximal aliasing color zone radius)2x aliasing velocity/peak velocity across mitral orifice. Effective mitral valve areas measured by three different methods (PLM, PHT, and PISA) were compared and correlated with those calculated by the "gold standard" invasive Gorlin's formula. The MVA derived from PHT, PLM, PISA and Gorlin's formula were 1.00 +/- 0.31cm2, 0.99 +/- 0.30 cm2, 0.95 +/- 0.30 cm2 and 0.91 +/- 0.29 cm2, respectively. The correlation coefficients (r value) between PHT, PLM, PISA, and Gorlin's formula, respectively, were 0.66 (P = 0.032, SEE = 0.64), 0.67 (P = 0.25, SEE = 0.72) and 0.80 (P = 0.002, SEE = 0.53). In conclusion, the PISA method is useful clinically in the measurement of effective mitral valve area in patients with rheumatic mitral valve stenosis. The technique is relatively simple, highly feasible and accurate when compared with the PHT, PLM, and Gorlin's formula. Therefore, this method could be a promising supplement to methods already in use.

Left Atrial Platelet Activity With Rheumatic Mitral Stenosis : Correlation Study of Severity and Platelet P-Selectin Expression by Flow Cytometry

Previous studies have demonstrated that platelet activation, evaluated by measuring the secretory substances of platelets (ie, platelet factor 4 and beta-thromboglobulin), occurs in the peripheral blood of patients with rheumatic mitral stenosis (MS). However, the differences in platelet activation between peripheral and atrial blood, and the relationship between regional left atrial platelet P-selectin expression and the severity of MS have never been investigated. A total of 16 patients with symptomatic MS undergoing percutaneous transluminal mitral valvuloplasty were studied (group 1). The fractions of platelets expressing P selectin in the prevalvuloplasty left atrial, right atrial, peripheral venous, and arterial blood were determined by flow cytometry. The mitral valve area was calculated by means of the Doppler pressure half-time method. Peripheral venous platelet activity also was evaluated in 23 control patients (including 15 healthy volunteers who were in sinus rhythm [group 2] and 8 patients who had chronic lone atrial fibrillation [group 3]). The fraction of peripheral venous platelets expressing P selectin among group 1 patients was significantly higher than that of group 2 or 3 patients (p = 0.008). In group 1 patients, the fraction of platelets expressing P selectin in the left atrium was significantly higher than that in the right atrium, the femoral vein, or the femoral artery (p < 0.01). Correlation analysis demonstrated that there was a significantly direct relationship between the severity of MS and the fraction of left atrial platelets expressing P selectin (p = 0.01; r = -0.620). The fraction of peripheral venous platelets expressing P selectin among group 2 patients did not differ from that of group 3 patients In patients with rheumatic MS, increased regional left atrial platelet P-selectin expression had a significantly direct relationship with the severity of MS. The increased regional left atrial platelet P-selectin expression was not reflected in peripheral venous blood samples.

Additional value of three-dimensional transesophageal echocardiography for patients with mitral valve stenosis undergoing balloon valvuloplasty

The objective of this study was to validate the additional value of 3-dimensional (3D) transesophageal echocardiography (TEE) for patients with mitral valve stenosis undergoing percutaneous mitral balloon valvotomy (PTMV). Therefore, in a series of 21 patients with severe mitral valve stenosis selected for PTMV, 3D TEE was performed before and after PTMV. The mitral valve area was assessed by planimetry pre- and post-PTMV; the mitral valve volume was assessed and attention was paid to the amount of fusion of the commissures. These results were compared with findings by 2-dimensional transthoracic echocardiography using pressure half-time method for assessment of mitral valve area, and were analyzed for the prediction of successful outcome. Pre-PTMV the mitral valve area assessed by 3D TEE was 1.0 ± 0.3 cm 2 vs 1.2 ± 0.4 cm 2 assessed by 2-dimensional transthoracic echocardiography ( P = .03) and post-PTMV it was 1.8 ± 0.5 cm 2 vs 1.9 ± 0.6 cm 2 (not significant), respectively. The mitral valve volume could be assessed by 3D TEE (mean 2.4 ± 2.5 cm 3) and was inversely correlated to a successful PTMV procedure ( P < .001). The 3D TEE method enabled a better description of the mitral valvular anatomy, especially post-PTMV. We conclude that 3D TEE will have additional value over 2-dimensional echocardiography in this group of patients, for selection of patients pre-PTMV, and for analyzing pathology of the mitral valve afterward.

Percutaneous transvenous mitral valvulotomy normalizes elevated circulating levels of tumor necrosis factor-alpha and interleukin-6 in mitral stenosis with heart failure.

W observing cytokine changes after percutaneous transvenous mitral valvulotomy (PTMV), 2 potential causes of cytokine expression are found in patients with rheumatic mitral stenosis (MS) and congestive heart failure (CHF): the rheumatic process1–3 and hemodynamic abnormalities.4–9 This study examines the circulating levels of tumor necrosis factor(TNF) and interleukin-6 (IL-6) in these patients, and the response of cytokine levels to treatment with PTMV. • • • The initial sample group included 22 patients presenting at Chung Gung Memorial Hospital (TaoYuan, Taiwan) with an echocardiographic diagnosis of moderate or severe MS (mitral valve area 1.5 cm) and CHF (New York Heart Association functional class II to IV). To avoid left ventricular pressure or volume overload, which proved to be associated with elevated circulating cytokines, patients with coexisting significant valvular lesions (of moderate or greater severity as seen on echocardiography) were excluded. Additionally, patients with diseases associated with elevated serum cytokines, such as infection, malignancy, chronic inflammation, or renal failure, were also excluded. Accordingly, 16 patients were enrolled. All patients underwent PTMV using the Inoue balloon technique, guided by on-line transesophageal echocardioography as previously described.10 The end point of PTMV was attainment of a valve area 1.5 cm, or a significant increase in the severity of mitral regurgitation evaluated by on-line transesophageal echocardiography. All patients were optimally treated with drugs as clinically indicated. Control subjects consisted of 10 ageand gender-matched healthy volunteers who were screened for the absence of organic heart disease or diseases associated with elevated cytokines by history, physical examination, electrocardiography, and echocardiography. The study protocol was approved by our institutional review committee, and written informed consent was obtained from all patients. Echocardiographic parameters were measured in control subjects and in the patient group immediately before catheterization and 6 months after PTMV. The mitral valve area was measured by 2-dimensional planimetry or the pressure half-time method.11,12 The left atrial end-systolic diameter was measured with M-mode echocardiography. The severity of mitral regurgitation was assessed by color flow mapping,13 and left ventricular ejection fraction was measured by Simpson’s rule. Left atrial pressure was measured immediately after the puncture needle entered the left atrium and after the last inflation of the balloon. Blood samples in the patient group were collected from the femoral vein and right atrium during cardiac catheterization before PTMV. Left atrial blood was sampled during PTMV through a Brockenbrough puncture needle immediately after the needle entered the left atrium. Six months after PTMV, samples of peripheral blood were collected by puncturing the antecubital vein. Peripheral blood samples were collected in the control subjects using the same methods as used for the patient group. Blood samples were stored on ice immediately after collection and separated by centrifugation at 1,500 rpm for 15 minutes. Serum was collected, aliquoted, and stored at 70°C until the assay. Commercially available enzyme-linked immunosorbent assay kits (QuantiGlo; RD the Department of Public Health and the Graduate Institute of Clinical Medicine, Chang Gung University, Taipei; and the Division of Cardiology, Cathay General Hospital, Taipei, Taiwan. Dr. Chang’s address is: First Cardiovascular Division, Chang Gung Memorial Hospital, Fu-Shin Road no. 5, Kwei-Shan, Tao-Yuan, Taiwan 333. E-mail: cchijen@adm.cgmh.org.tw. Manuscript received September 17, 2002; revised manuscript received and accepted December 27, 2002.

Location, size, and morphologic characteristics of left atrial thrombi as assessed by transesophageal echocardiography in relation to systemic embolism in patients with rheumatic mitral valve disease

A systemic embolism (SE) is one of the most important complications in patients with rheumatic mitral stenosis; the documented frequency of SE in patients with mitral stenosis varies from 10% to 45%.1,2 In surgical and postmortem clinicopathologic series, left atrial (LA) thrombus has been associated with SE.1,2 Recently, in transthoracic and transesophageal echocardiographic studies, the presence of spontaneous echocardiographic contrast (SEC) and/or thrombus within the left atrium has been found to increase the risk of SE. There are a limited number of studies evaluating the association between the risk of SE and the location, size, and morphologic characteristics of LA thrombi.3,5 Recently, it was reported that both the size and mobile character of LA thrombi were associated with increased risk of SE.14 We aimed to assess transesophageal echocardiographic correlates of recent SE, with specific reference to size, location, and morphologic characteristics of LA thrombi, and to investigate whether the intensity of left atrial SEC is related to the characteristics of concomitant LA thrombi in patients with rheumatic mitral valve disease. • • • The study population comprised 474 consecutive patients (320 women and 154 men, mean age 40 16 years) with rheumatic mitral valve disease who underwent transthoracic and transesophageal echocardiography 1 to 5 days before mitral valve surgery. Patient characteristics are listed in Table 1. Pure or predominant mitral stenosis was diagnosed in 333 patients (70.2%) and mitral regurgitation in the remaining patients. Two hundred sixty-seven patients (56.3%) had atrial fibrillation, and the remaining patients were in sinus rhythm. A history of anticoagulation was noted in 72 patients with history of SE; 34 patients with a history of silent LA thrombi were diagnosed by previous routine transthoracic echocardiographic studies. The mean value of the international normalized ratio was 2.5 1.2 in patients with SE and 2.6 1.1 in patients without SE. Mean time interval between the SE and the transesophageal echocardiographic study was 19 6 days. Patients with potential cardiac sources of SE, such as prosthetic heart valves; infective endocarditis; severe left ventricular dysfunction with or without left ventricular mural thrombi; and LA mass such as myxoma, protruding atheroma, aortic dissection, patent foramen ovale, and intracardiac shunts were excluded from the study. In patients without a history of SE, the presence of severe carotid artery disease was excluded by absence of systolic murmur over the carotid arteries. Transthoracic and transesophageal echocardiographic examinations were performed by a 3.25-MHz transthoracic and a 5-MHz multiplane transesophageal probes connected to a Vingmed CFM800 echocardiographic system (Horten, Norway). Written informed consent was obtained from each patient before entry into the study, and the protocol was approved by the institutional review board. Transesophageal echocardiography was performed after 4 hours of fasting, under topical anesthesia with 10% lidocaine and conscious sedation with intravenous midazolam. The mitral valve area was measured by pressure halftime and planimetric methods.15 Pure or predomFrom the Departments of Cardiology and Cardiovascular Surgery, Kosuyolu Heart and Research Hospital, Istanbul, Turkey. Dr. Ozkan’s address is: Department of Cardiology, Kosuyolu Heart and Research Hospital, Kadikoy, 81020, Istanbul, Turkey. E-mail: memoozkan@ superonline.com. Manuscript received June 29, 2002; revised manuscript received and accepted November 12, 2002. TABLE 1 Clinical and Echocardiographic Characteristics of Patients

Is the mitral valve area flow-dependent in mitral stenosis?: A dobutamine stress echocardiographic study

ObjectivesThe purpose of this study was to compare the effect of changes in flow rate on the mitral valve area (MVA) derived from two-dimensional echocardiographic planimetry and Doppler pressure half-time (PHT) methods in patients with mitral stenosis (MS). BackgroundDobutamine stress echocardiography has been proposed as a means of assessing the severity of MS. However, data regarding the effect of an increase in flow rate on MVA are limited. If MVA is indeed flow-dependent, this has important implications for the assessment of the severity of MS, particularly in the setting of reduced cardiac output (CO). MethodsDobutamine echocardiography was performed in 57 patients with isolated MS who were in sinus rhythm. The MVA was determined by planimetry and Doppler PHT methods. ResultsCardiac output increased by ≥50% in 27 patients (group I) and by <50% in 30 patients (group II). In group I, the MVA by planimetry increased by only 10.6 ± 2% and the MVA by PHT increased by 21.9 ± 4.8%. These changes were similar to those observed in group II (10.7 ± 3% and 14.8 ± 4%, respectively; p = NS), despite a much smaller increase in CO. A clinically important change (from the severe to mild category) occurred in only one patient when using the PHT method and in none by planimetry. ConclusionsChanges in flow rate result in small but clinically insignificant changes in echocardiographic MVA measurement. These methods provide an accurate assessment of MS severity in a majority of patients, independent of changes in flow rate.

Application of the Vena contracta Method for the Calculation of the Mitral Valve Area in Mitral Stenosis

Objectives: The vena contracta is the narrowest region of the regurgitant or stenotic jet just downstream the orifice and reflects the size of that orifice. This study was performed to assess the accuracy of the vena contracta width (VCW) in evaluating the severity of mitral stenosis (MS) and to compare the mitral valve area (MVA) determined by VCW with MVAs obtained by other more traditional echocardiographic methods. Methods: We studied 59 patients (43 females, 42 ± 14 years) with MS. VCW was measured in the apical four chamber view by Doppler color flow mapping. The largest diameter of the VCW during diastole was measured for at least three cardiac cycles and averaged. MVA was calculated from the following equation: πr², where r = VCW/2. MVA was also determined by planimetry, the pressure half-time method, and by the Gorlin formula. Results: In this study, the width of the vena contracta ranged from 0.89 to 1.73 cm (mean 1.30 ± 0.21). MVA, calculated based on the VCW, ranged from 0.63 to 2.35 cm² (mean 1.36 ± 0.41). MVA by VCW (1.36 ± 0.41 cm²) showed good correlations with three comparative techniques: (1) the cross-sectional area by planimetry (1.35 ± 0.36 cm², mean difference = 0.21 ± 0.16 cm², y = 0.91x + 0.14, r = 0.79, SEE = 0.26 cm², p < 0.001); (2) the area derived from the Doppler pressure half-time (1.27 ± 0.32 cm², mean difference = 0.22 ± 0.19 cm², y = 0.97x + 0.13, r = 0.76, SEE = 0.27 cm², p < 0.001), and (3) the area derived from the Gorlin equation in the 18 patients who underwent catheterization (1.27 ± 0.35 cm², mean difference = 0.19 ± 0.16, y = 0.98x + 0.05, r = 0.81, SEE = 0.26 cm², p < 0.001). Conclusions: These findings suggest that Doppler color flow imaging of the MS jet in the vena contracta can provide an accurate estimation of MVA and appears to be potentially applicable in the assessment of the severity of MS.

Comparison of proximal isovelocity surface area method with pressure half time method for evaluation of mitral valve area in patients undergoing balloon mitral valvuloplasty

Comparison of proximal isovelocity surface area method with pressure half time method for evaluation of mitral valve area in patients undergoing balloon mitral valvuloplasty

Left atrial spontaneous echo contrast in patients with rheumatic mitral valve stenosis in sinus rhythm: relationship to mitral valve and left atrial measurements

We studied 37 consecutive patients with mitral stenosis in sinus rhythm using transthoracic and transesophageal echocardiography to relate the presence of spontaneous echo contrast (SEC) in the left atrium with mitral valve area and left atrial dimensions. We also compared the value of left atrial area by planimetry with that of left atrial dimension by M mode in predicting presence of SEC and monitored the effect of anticoagulation on SEC. Transesophageal echocardiography demonstrated spontaneous echo contrast in 9/37 (24%) patients and thrombus in none. SEC continued to be present despite anticoagulation. Mitral valve orifice area by pressure half time method ( P=0.001) and by planimetry ( P=0.01), and left atrial area by planimetry ( P<0.05) were predictors to presence of SEC. Left atrial dimension by M mode examination failed to predict SEC. Cut off values were mitral valve orifice ≤1.4 cm 2 (agreement 86%) and left atrial area ≥25 cm 2 (agreement 81%). On multivariate analysis mitral valve area was the only independent predictor. SEC persisted despite anticoagulation. This supports the view that more than one mechanism is involved in the development of SEC.

A Case Report of Inoue Balloon Deformity Recognized during Percutaneous Mitral Valvuloplasty

Since the Inoue balloon was first introduced for percutaneous mitral valvuloplasty (PMV) in 1984, this procedure has come into widespread use because of its effectiveness, simplicity, and reduced exposure to X-ray radiation. It's the procedure’s complications include cardiac tamponade, atrial septal defect, thromboembolism, ventricular perforation, mitral regurgitation, and rarely balloon rupture. We report a case of Inoue balloon deformity during PMV in 62-year old woman with rheumatic mitral stenosis. Echocardiography revealed severe rheumatic mitral stenosis with a valvular area of 0.95 cm (by pressure half-time method), and an Echo score of 10 points. The PMV with Inoue balloon 28mm was performed. We inflated the balloon to 28 mm in diameter first, and to 29 mm second. A bulging deformity with asymmetrical overinflation of one side of both proximal and distal balloon was recognized. A bulging deformity at the proximal part of Inoue balloon after second inflation. Balloon was not ruptured. Following completion of the procedure, the mitral valve area increased to 1.8 cm. Moderate mitral regurgitation (grade II) was newly developed. This may be the first case of asymmetrical one side inflation and focal bulging deformity reported in Korea.(Korean Circulation J 2001;31(8):830-833)

Influence of left ventricular relaxation on the pressure half time of aortic regurgitation

BACKGROUNDThe severity of aortic regurgitation can be estimated using pressure half time (PHT) of the aortic regurgitation flow velocity, but the correlation between regurgitant fraction and PHT is weak.AIMTo test...

Application of Proximal Isovelocity Surface Area Method to Determine Prosthetic Mitral Valve Area

Background. In this study, we investigated the accuracy of orifice area determination of the prosthetic valve (Biocor) by using proximal isovelocity surface area method (PISA). Thirty-two patients (26 women, 6 men; mean age 44 ± 8.1 years) were studied. Eleven patients were in normal sinus rhythm and the rest were in atrial fibrillation. Associated valvular lesions were mild aortic regurgitation in 12 patients and moderate tricuspid regurgitation in 19 patients. Sizes of prosthetic valves were 27 to 31, and implantation duration was 4 to 8 years. Methods and Results. We analyzed the flow convergence zone proximal to the valve orifice with the concept of a hemispheric model. Mitral valve area (MVA) calculation was formulated by MVA = 2πr 2 × Va/Vm × (Vm/Vm – Va), where Vm is the maximal mitral velocity and Vm/Vm – Va is a correction factor to account for flattening of isotachs near the prosthetic orifice. MVA calculations by PISA were compared with pressure half-time (PHT), continuity equation (CONT), and color flow area (CFA) methods. Mitral valve areas were 2.17 ± 0.17 cm 2 , 2.22 ± 0.21 cm 2 , 2.19 ± 0.22 cm 2 , and 2.16 ± 0.17 cm 2 in PISA, CFA, PHT, and CONT methods, respectively. Values in the comparison of MVA measurements by different methods were PISA vs PHT, r = .86; PISA vs CFA, r = .77; and PISA vs CONT, r = .89. Conclusions. The PISA method gives reliable estimates of large orifices such as prosthetic valves. Although the best correlation was seen with the CONT method, results of this study also confirmed that the PISA method can be applied with reasonable accuracy. (J Am Soc Echocardiogr 1998;11:1056-63.)

Doppler pressure half-time method of assessing mitral valve area: Aortic insufficiency does not adversely affect validity

Objectives This study evaluated the effect of aortic insufficiency on the correlation of pressure half-time–derived mitral valve area with each of 2 standards for mitral valve area (planimetry and cardiac catheterization) in a prospectively assembled cohort of patients scheduled for percutaneous balloon mitral commissurotomy. Background Although Doppler pressure half-time has been validated as a method for assessing mitral valve area, most previous studies have suggested that this noninvasive technique overestimates mitral valve area in the setting of coexistent aortic insufficiency. Methods and Results Echocardiography and cardiac catheterization were performed on 212 consecutive patients scheduled for percutaneous balloon mitral commissurotomy. After excluding 35 patients who did not have aortography, the rest were divided into a “no aortic insufficiency [AI] group” ( n = 146) including those with trivial or no aortic insufficiency at catheterization and an “AI group” ( n = 31) including those with mild or moderate aortic insufficiency. The pressure half-time mitral valve area tended to slightly underestimate invasive valve area by 0.04 cm 2 in the AI group and to slightly overestimate invasive valve area by 0.06 cm 2 in the no AI group. This difference between the groups was not statistically significant ( P = .13). The pressure half-time mitral valve area tended to underestimate planimetered valve area by 0.11 cm 2 in the AI group and by 0.10 cm 2 in the no AI group. There was no difference between the 2 groups ( P = .94). Potential confounders that could theoretically mask the effect of aortic insufficiency on the pressure half-time (including age, heart rate, blood pressure, left ventricular diastolic pressure, ejection fraction, mitral regurgitation, and atrial fibrillation) were excluded by multivariable analyses. Conclusions The pressure half-time method of determining mitral valve area is not adversely affected by mild to moderate aortic insufficiency. This finding has implications for the utility of this technique in the rheumatic valvular disease population, in which mitral and aortic valve disease frequently coexist. (Am Heart J 1998;136:718-23.)

What Is the Validity of Continuous Wave Doppler Grading of Aortic Regurgitation Severity? A Chronic Animal Model Study

Continuous wave Doppler methods have been widely used clinically for evaluating the severity of aortic regurgitation; however, there have been no studies comparing these continuous wave Doppler methods with a strictly quantifiable reference for regurgitant severity. The purpose of this study was to test the applicability of continuous wave Doppler methods (deceleration slope and pressure half-time) for evaluation of chronic aortic regurgitation in an animal model. Eight sheep were studied 8 to 20 weeks after surgery to create chronic aortic regurgitation. Twenty-nine hemodynamically different states were obtained pharmacologically. A Vingmed 775 system was used for recording continuous wave Doppler traces with a 5 MHz annular array transducer directly placed on the heart near the apex. The aortic regurgitation was quantified as peak and mean regurgitant flow rates, regurgitant stroke volumes and regurgitant fractions determined with pulmonary and aortic electromagnetic flow probes and meters balanced against each other. Peak regurgitant flow rates varied from 1.8 to 13.6 L/min (6.3 ± 3.2 L/min) (mean ± SD), mean regurgitant flow rates varied from 0.7 to 4.9 L/min (2.7 ± 1.3 L/min), regurgitant stroke volume varied from 7.0 to 48.0 ml/beat (26.9 ± 12.2 ml/beat), and regurgitant fraction varied from 23% to 78% (53% ± 16%). Only marginal correlations were obtained between reference indexes and continuous wave Doppler deceleration slope and pressure half-time ( r = 0.55 to 0.74). A deceleration slope greater than 3 m/sec 2 and pressure half-time less than 400 msec did, however, provide 100% specificity for detecting severe AR (regurgitant fraction >50%). Our study shows that the continuous wave Doppler deceleration slope and pressure half-time methods have limited use for quantifying aortic regurgitation. (J Am Soc Echocardiogr 1998;11:332-7.)