Malignant natural history of asymptomatic severe aortic stenosis: benefit of aortic valve replacement

BACKGROUND

Patients with asymptomatic severe aortic stenosis (AS) are reported to have a benign prognosis and hence the American College of Cardiology/American Heart Association guidelines do not recommend aortic valve replacement (AVR) for patients with isolated asymptomatic severe AS. However, symptoms are subjective and would depend upon patient's life style. We examined the natural and unnatural history of initially asymptomatic patients with severe AS.

METHODS

A search of our echocardiographic database between 1993 and 2003 yielded 740 patients with severe AS defined as aortic valve area 0.8 cm2 or less. Thorough chart reviews were conducted to collect clinical and pharmacologic data. Of these, 338 patients were asymptomatic at the initial encounter forming the study cohort.

RESULTS

Patient characteristics were the following: age 71 +/- 15 years, males 51%, aortic valve area 0.72 +/- 0.17 cm2, left ventricular ejection fraction 0.59 +/- 0.17. Ninety-nine (29%) patients had AVR during a mean follow-up of 3.5 years. Survival at 1, 2, and 5 years in the nonoperated patients were 67%, 56%, and 38%, respectively, compared with 94%, 93%, and 90% in those who underwent AVR (p < 0.0001). The Cox regression model was used to adjust for the effect of 18 clinical, echocardiographic, and pharmacologic variables on survival. The adjusted hazard ratio for death with AVR was 0.17 (95% confidence interval [CI] 0.10 to 0.29). In the nonoperated group, renal insufficiency (risk ratio [RR] 3.1, 95% CI 1.5 to 6.6), beta blocker use (RR 0.52, 95% CI 0.31 to 0.88), statin use (RR 0.52, 95% CI 0.27 to 0.99), age (per year RR 1.03, 95% CI 1.02 to 1.05), and left ventricular ejection fraction (per % RR 0.99, 95% CI 0.98 to 1.00) were found to be the independent predictors of mortality. The benefit of AVR was further supported by sensitivity and propensity score analyses.

CONCLUSIONS

Our observational data indicate that the natural history of asymptomatic AS is not benign and that survival is dramatically improved by AVR. Survival of the asymptomatic unoperated or nonoperable patients may potentially be improved by the use of beta blockers and statins.

Survival benefit of aortic valve replacement in patients with severe aortic stenosis with low ejection fraction and low gradient with normal ejection fraction

BACKGROUND

Aortic stenosis (AS) is becoming increasingly common with the aging population. Many of these patients have reduced left ventricular (LV) ejection fractions (EF) or low transvalvular gradients resulting in reluctance to offer aortic valve replacement (AVR).

METHODS

Our echocardiographic database for the period of 1993 to 2003 was screened for severe AS (aortic valve area [AVA]

RESULTS

Of the 740 patients with severe AS, 194 (26%) had severe LV dysfunction defined as EF 0.35 or less and 168 (23%) a mean transvalvular gradient of 30 mm Hg or less. Low ejection fraction was not a prerequisite for a low gradient. The Univariate predictors of higher mortality in both groups included higher age, lower ejection fraction, renal insufficiency, and lack of aortic valve replacement. Lack of aortic valve replacement was a strong predictor of mortality after adjusting for 18 clinical, echocardiographic, and pharmacologic variables. There were 72 patients with EF 0.20 or less, of whom 18 had AVR, which was associated with a large survival benefit similar to the entire cohort. In the 52 patients with EF 0.55 or less and mean gradient less than 30 mm Hg, the 5-year survival with AVR was 90% compared with 20% without AVR (p < 0.0001) which was supported by propensity score analysis as well.

CONCLUSIONS

Severe LV dysfunction or a low transvalvular gradient is seen in about a quarter of patients with severe AS and there is a reluctance to offer AVR in these patients. Aortic valve replacement is associated with a large mortality benefit in these patients.

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MESH Headings

• Aged
• Aged, 80 and over
• Aortic Valve Stenosis/diagnostic imaging
• Aortic Valve Stenosis/mortality
• Aortic Valve Stenosis/surgery
• Blood Vessel Prosthesis
• Blood Vessel Prosthesis Implantation/methods
• Blood Vessel Prosthesis Implantation/mortality
• Cohort Studies
• Echocardiography, Doppler
• Female
• Follow-Up Studies
• Humans
• Male
• Middle Aged
• Probability
• Proportional Hazards Models
• Reference Values
• Retrospective Studies
• Risk Assessment
• Severity of Illness Index
• Stroke Volume/physiology
• Survival Analysis
• Treatment Outcome
• Ventricular Dysfunction, Left/diagnosis
• Ventricular Dysfunction, Left/mortality

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Amplitudes, durations, and timings of apically directed left ventricular myocardial velocities: I. Their normal pattern and coupling to ventricular filling and ejection

BACKGROUND

The left ventricular (LV) major axis shortening is an important determinant of its global function. But unlike the LV minor axis dynamics, the long-axis dynamics have not been well characterized. We investigated the amplitudes, durations, and timings of LV long-axis myocardial velocities and related them to LV filling and ejection in normal healthy volunteers.

METHODS AND RESULTS

Myocardial velocities from the basal, mid, and distal portions of the four LV walls were recorded from the apical window with spectral Doppler tissue imaging in 20 normal individuals. The timings, amplitudes, and durations were measured and compared both longitudinally and circumferentially. These were also related to mitral inflow and LV ejection. Analysis of the recordings indicated that there were three principal myocardial velocities: apically directed systolic velocity and atrially directed early and late diastolic velocities. The LV posterior wall had the highest shortening velocity and the amount of shortening. The lateral wall had the greatest amplitude of early diastolic lengthening velocity, amount of lengthening, and early to late lengthening velocity and integral ratios, probably indicating most favorable early diastolic properties. There was a striking synchrony in the myocardial velocities circumferentially. The myocardial velocities dropped progressively as the sampling site was moved distally and the LV apex was practically stationary. Although the onsets of the velocity profiles were simultaneous in the meridional orientation, their durations were shorter distally. All myocardial velocities preceded the corresponding blood flow velocities. They also ended before the corresponding blood flow velocities, this being more pronounced in the distal myocardial segments, indicating the presence of inertial factors responsible for the terminal portions of mitral and aortic flows.

CONCLUSIONS

Recording of apically directed myocardial velocities gives valuable insights into the regional myocardial function. These velocities show significant regional variations in healthy normal individuals. It is speculated that analysis of regional myocardial velocities may have a role in the diagnosis of early myocardial disease.

Amplitudes, durations, and timings of apically directed left ventricular myocardial velocities: II. Systolic and diastolic asynchrony in patients with left ventricular hypertrophy

BACKGROUND

Regional myocardial dysfunction may be the earliest manifestation of myocardial disease and can occur in the absence of abnormalities of global left ventricular (LV) function. The LV long-axis function, which is mainly due to subendocardial muscle fibers, may become abnormal in the presence of normal short-axis function. This study investigates the temporal and spatial characteristics of the LV long-axis function in patients with secondary LV hypertrophy in the presence of normal systolic function.

METHODS AND RESULTS

LV long-axis myocardial velocities were recorded in 18 patients with LV hypertrophy and preserved regional and global systolic function with Doppler tissue imaging. Apically directed myocardial velocities were recorded from the basal, mid, and apical segments of the four LV walls, and their amplitudes, timings, and durations were measured. The abnormalities uncovered by the analysis of regional myocardial velocities included (1) asynchrony in the onset of myocardial contraction circumferentially, (2) presence of postejection LV shortening, (3) asynchrony in the onset of early myocardial lengthening circumferentially, (4) reduced early myocardial lengthening velocity, (5) reduced early to late myocardial lengthening velocity and extents circumferentially, and (6) lack of variation in the basal myocardial velocities circumferentially in contrast to normal individuals.

CONCLUSIONS

Patients with secondary LV hypertrophy with preserved regional and global systolic performance have distinct abnormalities in the timings and amplitudes of apically directed myocardial velocities. These abnormalities may explain some of the changes in LV global diastolic behavior and may also serve as markers of early regional myocardial dysfunction.

Doppler-derived rate of left ventricular pressure rise. Its correlation with the postoperative left ventricular function in mitral regurgitation

A new Doppler-derived index of the rate of left ventricular (LV) pressure rise (delta P/delta t) was evaluated for the prognostic stratification of patients with chronic mitral regurgitation. The index is derived from the continuous wave Doppler mitral regurgitation signal by dividing magnitude of LV-left atrial pressure gradient rise (delta p) between 1 and 3 m/sec of the mitral regurgitation velocity signal by the time taken (delta t) for this change. We studied the LV delta P/delta t and other echocardiographic indexes of LV function before and after mitral valve surgery in 25 patients with chronic, severe mitral regurgitation in the absence of significant coronary artery disease. There was a good correlation between postoperative ejection fraction (EF) and the derived LV delta P/delta t (r = 0.75, p less than 0.001). The other echocardiographic parameters that correlated with postoperative EF were LV end-systolic dimension (r = -0.7, p less than 0.001), end-systolic volume (r = -0.69, p less than 0.001), end-diastolic dimension (r = -0.58, p less than 0.01), end-diastolic volume (r = -0.57, p less than 0.01), preoperative EF (r = 0.69, p less than 0.001), end-systolic wall stress (r = -0.61, p less than 0.01), and end-systolic wall stress normalized for end-systolic volume index (r = -0.45, p less than 0.05). With multiple regression, the LV delta P/delta t and LV end-systolic dimension (ESD) were shown to be independent predictors of postoperative EF. The postoperative EF could defined by the equation: 43 + 0.8 square root delta P/delta t--0.53 ESD (mm) (r = 0.86).(ABSTRACT TRUNCATED AT 250 WORDS)

Aortic valve replacement improves survival in severe aortic stenosis associated with severe pulmonary hypertension

BACKGROUND

Severe pulmonary arterial hypertension in patients with severe aortic stenosis (AS) carries a poor prognosis. There are limited data on the effect of aortic valve replacement (AVR) in these patients.

METHODS

Our echocardiographic database between 1993 and 2003 was searched for patients with severe AS defined as a Doppler estimated aortic valve area of 0.8 cm2 or less and severe pulmonary hypertension defined as a pulmonary arterial systolic pressure 60 mm Hg or greater. Of the 740 patients with severe AS, 119 (16%) had severe pulmonary hypertension forming the study cohort. The AVR was performed in 36 (30%) of these patients. Survival of patients with and without AVR were compared and adjusted for comorbidities and group differences using the Cox regression model.

RESULTS

Characteristics of patients with severe pulmonary hypertension; age 75 +/- 13 years, 39% women, left ventricular ejection fraction 41 +/- 20%. Patients who underwent AVR had a significantly higher five-year survival of 65% compared with 20% for those treated medically (p < 0.0001). The relative mortality risk associated with AVR was 0.28 (95% confidence interval 0.22 to 0.36) and was independent of age, gender, ejection fraction, diabetes, coronary disease, serum creatinine level, and concomitant medical therapy such as beta blockers, angiotensin converting inhibitors, and statins. The benefit of AVR was further supported by sensitivity and propensity score analyses. Patients on conservative therapy had a 30-day mortality of 30% and a one-year mortality of 70%.

CONCLUSIONS

Aortic valve replacement in patients with severe pulmonary hypertension secondary to severe AS is associated with a huge survival benefit. Medical therapy alone carries a dismal prognosis and AVR should be considered urgently in severe AS patients with severe pulmonary hypertension.

Mitral A velocity wave transit time to the outflow tract as a measure of left ventricular diastolic stiffness. Hemodynamic correlations in patients with coronary artery disease

BACKGROUND

Subjects in sinus rhythm have two distinct diastolic flow velocities in the left ventricular (LV) outflow tract directed toward the aortic valve. These follow E and A waves of the transmitral flow and are referred to as Er and Ar waves, respectively. The A wave transit time from the mitral valve to the LV outflow tract is shorter than that of the E wave and is shorter in those with LV hypertrophy and the aged, suggesting its possible dependence on LV late diastolic stiffness. METHODS AND RESULTS. We measured the peak-to-peak and onset-to-onset A wave transit times from the mitral valve to the LV outflow tract (AArp and AAro intervals, respectively) using Doppler echocardiography in 20 patients undergoing left heart catheterization for evaluation of coronary artery disease. These intervals were correlated with indices of LV late diastolic stiffness obtained from high-fidelity LV pressure tracings and angiographic volume assessments. The AArp and AAro intervals correlated significantly with LV Dp/DV (conventionally dP/dV) (r = -.68 and -.83, respectively), volume stiffness, V.Dp/DV (r = -.74 and -.80, respectively) and LV (V/P) (Dp/DV) (r = -.69 and -.74, respectively). The AAro interval correlated better with the square roots of LV Dp/DV and volume stiffness (r = -.86 and -.87, respectively).

CONCLUSIONS

We conclude that AArp and AAro intervals are easily obtainable Doppler parameters that reflect LV late diastolic stiffness in patients with coronary artery disease and possibly in other patients groups.

Prognostic implications of mitral regurgitation in patients with severe aortic regurgitation

BACKGROUND

Mitral regurgitation (MR) is common in those with severe aortic regurgitation (AR) and can predispose to atrial fibrillation, heart failure, and a need for mitral valve surgery during aortic valve replacement (AVR). However, little data exist as to its clinical and prognostic implications.

METHODS AND RESULTS

Search of our echocardiographic data base between 1993 and 2007 yielded 756 patients with severe AR. with comprehensive clinical data from chart review and mortality data from National Death Index. Mortality was analyzed as a function of MR severity. Effect of AVR and concomitant mitral valve repair were investigated. Patient characteristics were age, 61±17 years; female sex, 41%; and ejection fraction, 54±19%. MR grade ≥2+ was present in 343 (45%) patients: 2+ in 152 (20%), 3+ in 93 (12%), and 4+ in 98 (13%). There was a progressive decrease in survival with each grade of MR (P<0.0001). Performance of AVR was associated with a better survival in those with 3 or 4+ MR (P=0.02). In addition, concomitant mitral valve repair in these patients resulted in a better survival (hazard ratio, 0.29; P=0.02).

CONCLUSIONS

MR is common in patients with severe AR, with 3 or 4+ MR occurring in a quarter of these patients. It is an independent predictor of reduced survival. Performance of AVR and concomitant mitral valve repair is associated with a better survival. Development of MR should serve as an indication for AVR even in asymptomatic patients.

Prognostic significance of atrial fibrillation is a function of left ventricular ejection fraction

BACKGROUND

Atrial fibrillation (AF) has been reported to be associated with decreased survival in population-based studies. Its prognostic importance in end-stage heart failure is not clear.

METHODS AND RESULTS

We investigated the prognostic implications of AF as function of left ventricular (LV) ejection fraction (EF) in 8,931 consecutive patients undergoing echocardiography at our medical center between 1990 and 1999. Patient characteristics were: age 66 +/- 13 years, EF 51 +/- 15, AF in 1,203 patients. There were 1,911 deaths over a mean follow up of 913 days. The prevalence of AF was 11% in patients with normal left ventricular ejection fraction (LVEF) (EF >/= 55%, n = 5, 130), and 18% each in those with mild (EF 41-54%, n = 1209), moderate (EF 26-40%, n = 1183) and severe reductions in left ventricular ejection fraction (LVEF) (EF /= 450, raising a possibility of enhanced susceptibility of these patients.

CONCLUSIONS

The effect of AF on mortality diminishes with worsening LV function and is absent in those with severe LV dysfunction. Susceptibility of patients with QT prolongation to AF mortality warrants further attention.

Newer Doppler measures of left ventricular diastolic function

Left ventricular (LV) diastolic dysfunction is an important cause of heart failure, and recent advances in the application of Doppler techniques allow a semiquantitative assessment of LV diastolic performance. This review discusses the use of Doppler echocardiography in the comprehensive assessment of LV diastolic function and performance in terms of the normal mitral and pulmonary venous flow profiles, their physiologic basis, and alterations in diseased states. There is also a discussion on the newer aspects of mitral flows such as relative durations of mitral A and pulmonary vein AR waves, E- and A- wave propagation inside the LV with their hemodynamic correlates, and derivation of ventricular dP/dt and Tau from the mitral regurgitation velocity profile. Analysis of these flow profiles and the other Doppler measures alluded to above allow one to make a fairly precise hemodynamic assessment of a patient in terms of left atrial pressure, LV relaxation and stiffness and the profile of LV diastolic pressure in terms of pre- 'a' wave and 'a' wave pressures and ventricular end-diastolic pressure.

A case of mitral-aortic intervalvular fibrosa aneurysm with unique flow patterns and long-term natural survival

We report a patient with a large aneurysm of mitral-aortic intervalvular fibrosa as a complication of prosthetic aortic valve endocarditis diagnosed on transthoracic echocardiography. This aneurysm began to expand with atrial systole, filled fully during ventricular systole, and collapsed in diastole on transesophageal examination. The patient refused corrective surgery and has survived on medical treatment for close to 2 years.

Clinical and echocardiographic correlates of mitral E-wave transmission inside the left ventricle: potential insights into left ventricular diastolic function

The mitral inflow wave is initially directed to the left ventricular apex and then turns around facing the left ventricular outflow tract. The E and A waves are transmitted to the left ventricular outflow tract where they are registered as Er and Ar waves, respectively. We hypothesized that the E-wave transit time to the left ventricular outflow tract recorded as the E-Er interval may depend on left ventricular early diastolic performance such as relaxation. This hypothesis was tested in clinical settings known to have abnormal left ventricular relaxation. Mitral E and left ventricular outflow tract Er waves were recorded with pulsed wave Doppler technique in 63 subjects: 25 healthy subjects, 18 patients with secondary left ventricular hypertrophy, and 20 patients with hypertrophic cardiomyopathy. The E-Er interval was measured from the onset of E wave to the onset of Er wave timed to the R wave of the electrocardiogram. The E-Er interval ranged from 45 to 300 msec: 96 +/- 28 msec in the controls, 127 +/- 46 msec in patients with left ventricular hypertrophy (p = 0.0091 versus controls), and 179 +/- 57 msec in patients with hypertrophic cardiomyopathy (p < 0.0001 versus controls). It correlated with left ventricular free wall thickness (r = 0.42, p = 0.0006), thickness of the ventricular septum (r = 0.43, p = 0.0004), left ventricular end-diastolic diameter (r = -0.38, p = 0.0022), left ventricular end-systolic diameter (r = -0.55, p < 0.0001), left ventricular isovolumic relaxation time (r = 0.39, p = 0.0063), RR interval (r = 0.28, p = 0.045), mitral E/A velocity ratio (r = -0.33, p = 0.010), and E-wave deceleration time (r = 0.38, p < 0.0044) but not with age. Multivariate analysis with all the previously mentioned variables and the group the patient belonged to as the dichotomous variable showed that the grouping variable was the sole independent determinant of the E-Er interval (multiple r = 0.74). The E-Er interval is an easily measurable Doppler parameter which is increased in left ventricular hypertrophy and hypertrophic cardiomyopathy. It is related to left ventricular wall thickness, left ventricular isovolumic relaxation time, mitral E/A velocity ratio, and E-wave deceleration time and may provide useful insight into left ventricular early diastolic performance-possibly the relaxation process.

Biological correlates of QT interval and QT dispersion in 2,265 patients with left ventricular ejection fraction < or =40%

Increased QT interval and QT dispersion have been associated with increased mortality in a variety of cardiovascular disorders including heart failure. However, the biological correlates of these abnormalities are not clear. QTc and QTd were measured in an automated fashion from digitized electrocardiograms in 2,265 patients with an LV ejection fraction Collapse

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MESH Headings

• Aged
• Electrocardiography
• Female
• Heart Rate
• Humans
• Male
• Stroke Volume
• Ventricular Dysfunction, Left/physiopathology

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Three-Dimensional Echocardiographic Reconstruction of the Left Ventricle by a Transesophageal Tomographic Technique: In Vitro and In Vivo Validation of its Volume Measurement

Accurate determination of left ventricular (LV) volume has important therapeutic and prognostic implications in patients with cardiac disease. Volume estimations by two-dimensional techniques are not very accurate due to geometric assumptions. OBJECTIVES: To validate LV volume determinations by a new transesophageal three-dimensional echocardiographic technique. We performed three-dimensional reconstruction of the LV using an echo-computed tomographic (CT) technique based on serial pullback parallel slice imaging technique in both in vitro and in vivo settings. Fourteen latex balloons with various sizes (30-235 mL) and shapes (conical, pear shaped, round, elliptical, and aneurysms in various locations) filled with known volumes of water were imaged in a water bath. From the static three-dimensional image, the LV long axis was defined and the LV was sectioned perpendicular to this axis into 2-mm slices. The volume of each slice was calculated with the observer blinded to the actual volume as the product of the slice thickness and the manually traced perimeter of the slice and the LV volume as the sum of the volumes of the slices (Simpson's method). The calculated LV volume closely correlated with the actual volume (r = 0.99, P < 0.0001, calculated volume = 1.06x - 11.3, Deltavolume = -5.7 +/- 10.0 cc). Using the same system, transesophageal echocardiographic (TEE) images of the LV were obtained in 15 patients gated to respiration and ECG. Satisfactory dynamic three-dimensional reconstruction of the LV was possible in ten patients. The three-dimensional LV volumes (systolic and diastolic) using Simpson's method correlated well with those obtained from biplane or multiplane TEE images using the area length method (r = 0.89, p < 0.0001, y = 12.7 + 0.84x, Deltavolume = 1.3 +/- 18.1 cc). The LV major-axis diameters by the two methods showed very close correlations as well (r = 0.86, P < 0.0001, y = 19 + 0.74x, Deltadiameter = 1.0 +/- 7.2 mm). We conclude that three-dimensional LV volume calculation by the echo-CT technique is intrinsically sound, is independent of LV geometry, and with some limitations, is applicable in vivo. (ECHOCARDIOGRAPHY, Volume 13, November 1996)

Constrictive pericarditis causing extrinsic mitral stenosis and a left heart mass

Constrictive pericarditis is a fibrotic process involving both layers of the pericardium and is known to give rise to obstruction to blood flow in the right heart. We report a patient with constrictive pericarditis who had echocardiographic features of mitral stenosis caused by a fibrocalcific mass lesion involving the mitral annulus with infiltration into the base of the posterior mitral leaflet. To our knowledge, this has not been reported in the literature.

Relative duration of transmitted mitral A wave as a measure of left ventricular end-diastolic pressure and stiffness

BACKGROUND AND OBJECTIVES

The mitral A wave is transmitted to the left ventricular (LV) outflow tract where it is registered as Ar wave. We have related its transit time to the LV late diastolic stiffness. We also observed incidentally that the duration of the transmitted Ar wave exhibited marked variability and hence investigated its hemodynamic correlates.

METHODS AND RESULTS

Mitral A wave and the Ar wave in the LV outflow tract were recorded using pulsed wave Doppler technique simultaneous with high fidelity LV pressure recordings in 20 patients undergoing cardiac catheterization. A high-speed contrast left ventriculogram was obtained as well. The duration of both these wave forms were measured and A wave duration minus the Ar wave duration was measured. The A minus Ar wave duration (range 0-95 ms) correlated with LV end-diastolic pressure (r = 0.54, P = 0.014, range 4-32 mmHg), LV late diastolic stiffness (r = 0.62, P = 0.004, range 0.1-1.6 mmHg/ml) and the amount of LV pressure rise with atrial contraction (r = 0.67, P = 0.001, range 2-13 mmHg).

CONCLUSION

A minus Ar wave duration is an easily obtainable Doppler parameter that is related to LV late diastolic filling pressures and stiffness and gives insights into aspects of LV diastolic function.

Value of Cardiovascular Magnetic Resonance Imaging-Derived Baseline Left Ventricular Ejection Fraction and Volumes for Precise Risk Stratification of Patients With Ischemic Cardiomyopathy: Insights From the Surgical Treatment for Ischemic Heart Failure (STICH) Trial

This study tests the hypothesis that cardiovascular magnetic resonance–derived left ventricular ejection fraction and volumes would provide improved risk stratification in patients undergoing coronary artery bypass surgery for ischemic cardiomyopathy.

An integrated measure of left ventricular diastolic function based on relative rates of mitral E and A wave propagation

BACKGROUND AND OBJECTIVES

The mitral E wave propagation inside the left ventricle is slowed in patients with abnormal left ventricular (LV) relaxation with a prolongation of its transit time to the LV outflow tract (T(e)). On the contrary, the mitral A wave propagation is faster in those with elevated LV end-diastolic stiffness, resulting in a shortening of its transit time (T(a)). We hypothesized that the T(e)/T(a) ratio may serve an integrated measure of global LV diastolic function.

METHODS AND RESULTS

The T(e)/T(a) ratio was measured with Doppler echocardiography in 94 subjects: 25 normal subjects, 38 patients with LV hypertrophy (18 with secondary LV hypertrophy and 20 with hypertrophic cardiomyopathy), and 31 patients undergoing left heart catheterization for clinical indications. The T(e)/T(a) ratio was 1. 98 +/- 0.61 in the normal subjects, 3.32 +/- 0.93 in patients with secondary LV hypertrophy (P <.0001 vs normal), and 3.18 +/- 1.36 in patients with hypertrophic cardiomyopathy (P =.0003 vs normal). In the invasive group the T(e)/T(a) ratio (range 0.56 to 3.60) correlated significantly with Tau (r = 0.76, P <.0001), peak negative dP/dt (r = -0.46, P =.01), the LV late diastolic stiffness index (r = 0.57, P =.0013), LV pre-A wave pressure (r = 0.46, P =. 0096), LV end-diastolic pressure (r = 0.58, P =.0007), and the amount of LV pressure rise with atrial systole (r = 0.52, P =.0032) but not with the heart rate. Tau and LV stiffness were its sole determinants by stepwise multiple regression (R = 0.82).

CONCLUSIONS

The ratio of mitral E and A wave transit times inside the LV (T(e)/T(a) ratio) is closely related to LV relaxation, its late diastolic stiffness, and filling pressures and gives valuable insights into LV diastolic performance.

Rates of left ventricular isovolumic pressure rise and fall from the aortic regurgitation velocity signal: description of the method and validation in human beings

BACKGROUND

Aortic regurgitation results from a pressure gradient across the aortic valve during left ventricular (LV) isovolumic relaxation, LV filling, and isovolumic contraction periods. Assuming the applicability of the simplified Bernoulli equation to this pressure-flow relation and constancy of aortic pressure during LV isovolumic relaxation and contraction periods, one can theoretically obtain estimates of the rates of LV isovolumic pressure fall and rise (deltaP/delta t) from the aortic regurgitation (AR) velocity signal.

METHODS AND RESULTS

Mitral regurgitation (MR) and AR signals were recorded by using the continuous wave Doppler technique in 26 patients with combined mitral and aortic regurgitant lesions. The LV negative deltaP/delta t was obtained by dividing the time taken for the AR velocity to rise from 1 m/sec to 2.5 m/sec into 21 mm Hg, which is the estimated LV pressure drop between these points. In a similar fashion, the LV positive deltaP/delta t was obtained between 2.5 m/sec and 1 m/sec of the fast decelerating portion of the AR signal. The LV negative deltaP/delta t by the AR method ranged from 420 to 3500 mm Hg/sec and correlated well with that obtained by the MR method obtained in a blinded fashion (r = 0.95, p < 0.0001). The mean (SD) difference between the two methods was 30 (129) mm Hg/sec. Similarly, the LV positive deltaP/delta t by the AR method (range 420 to 2625 mm Hg/sec) correlated closely with that obtained by the MR method (r = 0.93, p < 0.0001), with the mean (SD) difference between the two methods being 38 (138) mm Hg/sec.

CONCLUSIONS

Preliminary data presented in this study indicate the feasibility of obtaining a reliable estimate of LV positive and negative deltaP/delta t from the AR velocity profile. Thus the examination of the AR signal may give valuable insights into both LV systolic and diastolic functions.