Early Detection of Left Ventricular Dysfunction by Doppler Tissue Imaging and N-terminal Pro-B-type Natriuretic Peptide in Patients with Symptomatic Severe Aortic Stenosis

Peak systolic myocardial velocity in patients undergoing surgical aortic valve replacement for severe aortic stenosis: prognostic value and natural course

Myocardial systolic longitudinal function has been known to decrease in patients with severe aortic stenosis (AS). Preoperative peak systolic myocardial velocity at the septal mitral valve annulus (S'), measured using Doppler tissue imaging, was used as an indicator for myocardial systolic longitudinal function. The prognostic value and natural course of S' after surgical aortic valve replacement for severe AS have not been elucidated. This retrospective observational study included patients from January 2006 to December 2018. The patients were divided to 2 groups (pre-S'_HIGH vs. pre-S'_LOW) with a cut-off 5.4 cm/s of preoperative S' (pre-S') that was identified by restricted cubic spline curve. The primary outcome was postoperative long-term all-cause mortality. Nine hundred and five patients were analyzed. All-cause mortality rate at the median follow-up period of 5.2 years was 12% in pre-S'_LOW and 8% in pre-S'_HIGH. Multivariate analysis showed that pre-S'_LOW was associated with an increased all-cause mortality (hazard ratio, 1.60; 95% confidence interval, 1.04-2.48; P = 0.032). Significantly different trajectories of postoperative S' (post-S') were found between two groups (P < 0.001 for difference): In pre-S'_LOW, post-S' increased within 6 months after surgery, and gradually decreased over time, whereas it slowly decreased up to 5 years after surgery and then reached a plateau in pre-S'_HIGH. The difference in pre-S' level maintained over time, and remained consistent in the adjusted analysis. Pre-S' < 5.4 cm/s was found to be associated with an increased long-term all-cause mortality. In addition, the trajectories for post-S' were different according to pre-S', which remained after adjustment.

Plasma haptoglobin level can augment NT-proBNP to predict poor outcome in patients with severe acute decompensated heart failure

To evaluate the use of plasma haptoglobin (Hp) levels and N-terminal pro-B-type natriuretic peptide (NT-proBNP) in predicting survival in patients with severe acute decompensated heart failure (AHF). Management of AHF is challenging. Identifying markers associated with patient prognosis in this disease is clinically important. In this prospective observational study, plasma Hp and NT-proBNP levels were measured. Receiver operating characteristic (ROC) curves were used to identify cut-offs of Hp and NT-proBNP with the greatest specificity and sensitivity for predicting overall survival and cardiovascular-related survival. The cut-off values were tested in patients with AHF (n=41). The cut-off value with the greatest specificity and sensitivity with respect to overall survival and for cardiovascular-related survival for Hp was 177. 1 ng/mL for both outcomes and for NT-proBNP was 34 246.0 pg/mL and 11 848.5 ng/mL, respectively. Using these cut-off values, this study found that patients with lower baseline Hp levels (<177. 1 ng/mL) or higher baseline NT-proBNP (≥34 246 pg/mL) were more likely to have shorter overall survival. Similarly, patients with <177. 1 ng/mL of Hp and ≥11 848.5 pg/mL of NT-proBNP had the highest risk of death related to cardiovascular disease. Our findings indicate that Hp and NT-proBNP using specific cut-off values for AHF can be used to determine risk of survival in these patients.

Aortic Stenosis, a Left Ventricular Disease: Insights from Advanced Imaging

Aortic stenosis (AS) is the most common primary valve disorder in the elderly with an increasing prevalence. It is increasingly clear that it is also a disease of the left ventricle (LV) rather than purely the aortic valve. The transition from left ventricular hypertrophy to fibrosis results in the eventual adverse effects on systolic and diastolic function. Appropriate selection of patients for aortic valve intervention is crucial, and current guidelines recommend aortic valve replacement in severe AS with symptoms or in asymptomatic patients with left ventricular ejection fraction (LVEF) <50 %. LVEF is not a sensitive marker and there are other parameters used in multimodality imaging techniques, including longitudinal strain, exercise stress echo and cardiac MRI that may assist in detecting subclinical and subtle LV dysfunction. These findings offer potentially better ways to evaluate patients, time surgery, predict recovery and potentially offer targets for specific therapies. This article outlines the pathophysiology behind the LV response to aortic stenosis and the role of advanced multimodality imaging in describing it.

Human heart failure biomarker immunosensor based on excessively tilted fiber gratings

A label-free immunosensor platform based on excessively tilted fiber gratings (Ex-TFGs) was developed for highly specific and fast detection of human N-terminal pro-B-type natriuretic peptide (NT-proBNP), which is considered a powerful biomarker for prognosis and risk stratification of heart failure (HF). High-purity anti-NT-proBNP monoclonal antibodies (MAbs) prepared in our laboratory were immobilized on fiber surface through the staphylococcal protein A (SPA) method for subsequent specific binding of the targeted NT-proBNP. Utilizing fiber optic grating demodulation system (FOGDS), immunoassays were carried out in vitro by monitoring the resonance wavelength shift of Ex-TFG biosensor with immobilized anti-NT-proBNP MAbs. Lowest detectable concentration of ~0.5ng/mL for NT-proBNP was obtained, and average sensitivity for NT-proBNP at a concentration range of 0~1.0 ng/mL was approximately 45.967 pm/(ng/mL). Several human serum samples were assessed by the proposed Ex-TFG biomarker sensor, with high specificity for NT-proBNP, indicating potential application in early diagnosing patients with acute HF symptoms.

Intraoperative improvement in left ventricular peak systolic velocity predicts better short-term outcome after transcatheter aortic valve implantation

OBJECTIVES

Left ventricular function is expected to improve after transcatheter aortic valve implantation due to the acute reduction in afterload, but does not occur in all patients. We hypothesized that the immediate intraoperative response in systolic left ventricular longitudinal motion during the procedure could be a predictor of short-term outcome.

METHODS

Sixty-four patients treated with transcatheter aortic valve implantation for severe aortic stenosis were included. Transoesophageal 4- and 2-chamber echocardiograms were obtained immediately prior to and ∼15 min after valve implantation. Patients were defined as responders if their average left ventricular longitudinal peak systolic velocity increased by ≥20% from the preimplantation value and was related to the 3-month outcome.

RESULTS

Thirty-five patients were classified as responders, with an increase in the intraoperative longitudinal peak systolic velocity from an average of 2.2 ± 0.8 to 3.1 ± 1.1 cm/s (P < 0.001); the velocity was unchanged in the remaining 29 patients, who averaged 2.4 ± 1.1 cm/s. There were significantly fewer adverse cardiac events in the responder group at the 3-month follow-up (20 vs 45%, P = 0.03) and the New York Heart Association class was significantly better in the responders compared with non-responders. Responders had a significant reduction in N-terminal probrain natriuretic peptide levels [243 (113-361) vs 163 (64-273), P = 0.004] at the 3-month follow-up, whereas non-responders did not [469 (130-858) vs 289 (157-921), P = 0.48].

CONCLUSIONS

An immediate improvement in the longitudinal peak systolic velocity during the transcatheter aortic valve implantation procedure predicted a better short-term outcome and may be useful in identifying patients who are at risk of a less favourable outcome after transcatheter aortic valve implantation.

Relation between E/e' ratio and NT-proBNP levels in elderly patients with symptomatic severe aortic stenosis

BACKGROUND

Symptoms in the elderly patients with severe aortic stenosis (AS) and co-morbidities seem to lack in specificity. Therefore, objective parameters for increased left ventricular(LV) filling pressures are needed. The aim of this study was to investigate the correlation between the septal, lateral and average E/e' ratio and the value of the N-terminal pro-hormone of brain natriuretic peptide (NT-proBNP).

METHODS

Two-hundred-fifty consecutive symptomatic patients (mean age 80 ± 8 years, 52% men) with severe AS underwent transthoracic echocardiography and NT-proBNP measurement.

RESULTS

In the overall population the septal E/e' (r = 0,459, r(2) = 0,21, P <0,0001), lateral E/e' (r = 0,322, r(2) = 0,10, P <0,0001), and the average E/e' (r = 0,432, r(2) = 0,18, P <0,0001) were all significantly correlated to NT-proBNP. After the exclusion of patients with confounders (more than mild aortic or mitral regurgitation, severe renal dysfunction, obesity or severe COPD) the septal E/e' (r = 0,584, r(2) = 0,34, P <0,0001), lateral E/e' (r = 0,377, r(2) = 0,14, P <0,0001), and the average E/e' (r = 0,487, r(2) = 0,24, P <0,0001) were all significantly better correlated to NT-proBNP. In obese patients no significant correlations were seen. Previous bypass surgery did not alter the correlations.

CONCLUSIONS

In elderly patients with severe symptomatic AS there is a significant correlation between the E/e' ratio and NT-proBNP, in particular after exclusion of confounders. The correlation was best for the septal E/e' ratio and was preserved in patients with a history of bypass surgery.

The left ventricle in aortic stenosis--imaging assessment and clinical implications

Aortic stenosis has an increasing prevalence in the context of aging population. In these patients non-invasive imaging allows not only the grading of valve stenosis severity, but also the assessment of left ventricular function. These two goals play a key role in clinical decision-making. Although left ventricular ejection fraction is currently the only left ventricular function parameter that guides intervention, current imaging techniques are able to detect early changes in LV structure and function even in asymptomatic patients with significant aortic stenosis and preserved ejection fraction. Moreover, new imaging parameters emerged as predictors of disease progression in patients with aortic stenosis. Although proper standardization and confirmatory data from large prospective studies are needed, these novel parameters have the potential of becoming useful tools in guiding intervention in asymptomatic patients with aortic stenosis and stratify risk in symptomatic patients undergoing aortic valve replacement.

This review focuses on the mechanisms of transition from compensatory left ventricular hypertrophy to left ventricular dysfunction and heart failure in aortic stenosis and the role of non-invasive imaging assessment of the left ventricular geometry and function in these patients.

Transcatheter aortic valve implantation and intraoperative left ventricular function: a myocardial tissue Doppler imaging study

OBJECTIVE

Transcatheter aortic valve implantation in patients turned down for surgical aortic valve replacement is a high-risk procedure. Severe aortic stenosis is associated with impaired left ventricular longitudinal motion, and myocardial peak systolic velocity is a measure of left ventricular function in these patients. The present study aimed to quantify the acute changes in left ventricular function during the procedure by using myocardial tissue Doppler imaging and transthoracic cardiac output measurements.

DESIGN

Prospective observational study.

SETTING

Tertiary care university hospital.

PARTICIPANTS

40 patients with severe aortic stenosis scheduled for transcatheter aortic valve implantation.

INTERVENTIONS

Transesophageal 4-chamber and 2-chamber echocardiograms were performed immediately before and ~15 minutes after valve implantation. Longitudinal myocardial peak systolic velocity was obtained by tissue Doppler imaging from 8 basal segments and averaged. Cardiac output was measured by the lithium dilution method, and systemic vascular resistance index and stroke volume were calculated.

MEASUREMENTS AND MAIN RESULTS

Longitudinal myocardial peak systolic velocity improved immediately after valve implantation, from -2.3±0.8 to -3.0±1.1 cm/sec (p<0.001); this represented an average increase of 31%±33%. Cardiac output increased from 3.2±0.8 L/min to 3.6±0.9 L/min (15%±33%; p = 0.04). This was due to increased heart rate (59±9 beats/min to 72±12 beats/min; p<0.001) and not to an improved stroke volume. Systemic vascular resistance index was reduced from 2,937±984 dynes*sec/cm(5)/m(2) to 2,436±730 dynes*sec/cm(5)/m(2) (p = 0.003).

CONCLUSION

Intraoperative echocardiography tissue Doppler imaging detected immediate improvement in left ventricular long-axis motion after transcatheter aortic valve implantation. The method provided detailed information not obtainable by routine hemodynamic monitoring.

Echocardiographic predictor of acute heart failure after spine surgery: a novel tissue Doppler index associated with a potentially fatal complication of the operation

BACKGROUND CONTEXT

Acute heart failure (HF) is a potentially fatal complication after spine surgery.

PURPOSE

We sought to identify clinical and echocardiographic predictors of postoperative HF in spine surgery patients.

STUDY DESIGN

Retrospective observational study.

PATIENT SAMPLE

A total of 305 patients (128 men; age, 65 ± 9 years) who underwent spine surgery were consecutively enrolled. A transthoracic echocardiography was performed to all patients before the index operation. Patients with a history of HF or with left ventricular (LV) systolic dysfunction (LV ejection fraction <50%) were excluded.

OUTCOME MEASURES

Heart failure was defined according to the Framingham criteria. The presence of postoperative dyspneic symptom and the sign of bilateral ankle edema were recorded by the physicians. Chest X-ray was mandatory for all patients and interpreted by the two physicians, including at least one radiologist.

METHODS

Clinical, operative, and echocardiographic parameters were compared between patents with and without acute HF during the postoperative period (duration, 11 ± 9 days). This study was supported by Boryung Pharmaceutical Company (Seoul, Republic of Korea; 13,440 USD).

RESULTS

Postoperative HF occurred in 31 patients (10%). Compared with those without postoperative HF, these patients were older (73 ± 7 vs. 64 ± 9 years), had longer anesthesia time (7.4 ± 4.2 vs. 3.6 ± 2.1 hours), and were treated with a greater volume of fluid replacement during the operation (3.8 ± 0.7 vs. 1.3 ± 0.1 L) (p<.05 for all). On echocardiographic evaluation, the ratio of early diastolic mitral inflow velocity to early diastolic mitral annular velocity (E/E') was higher (11 vs. 8) and left atrial volume index was larger (20 ± 6 vs. 17 ± 6 mL/m(2)) in patients with HF than in the control group (p<.05 for all), whereas the differences in LV ejection fraction and LV size were not significant. In multivariate analysis, E/E' (odds ratio, 1.399; 95% confidence interval, 1.169-1.674; p<.0001), age, and quantity of replaced volume during surgery were independent predictors of postoperative HF.

CONCLUSIONS

Acute HF after spine surgery was rather common even in previously healthy patients. E/E' reflecting LV filling pressure predicted postoperative HF in patients who underwent spine surgery.

Assessing prognosis of pulmonary embolism using tissue-Doppler echocardiography and brain natriuretic peptide

Objective:

To assess prognosis of pulmonary thromboembolism using tissue Doppler echocardiography and brain natriuretic peptide.

Methods:

Patients aged over 18 years were evaluated within 24 hours of confirmed diagnosis (chest tomography/pulmonary scintigraphy) of pulmonary embolism using two-dimensional echocardiography and tissue Doppler for right ventricular systolic (s') velocities, strain, tissue tracking and myocardial performance index. Plasma brain natriuretic peptide was also obtained within 24 hour. The influence of echocardiographic and clinical variables on mortality was examined (up to 12 months) using Cox regression analysis.

Results:

Out of 118 patients, 100 patients were included in the study (60 males, aged 55±17 years). Right ventricular dysfunction was observed in 28% using two-dimensional echocardiography. Tissue Doppler right ventricular variables (s' velocities, tissue tracking and strain) were decreased only for patients with right ventricular dysfunction, whereas myocardial performance index and systolic pulmonary artery pressure were increased. Mean brain natriuretic peptide value was 66±111pg/mL, also increased in patients with right ventricular dysfunction (136±146pg/mL). Mortality was 11% and related to age, malignancy and brain natriuretic peptide levels. The only echocardiographic variables capable of predicting events by univariate analysis were pulmonary pressure and right ventricular s' velocity. However, multivariate analysis showed only malignancy to predict mortality in this group.

Conclusion:

Lower tissue Doppler systolic velocities and elevated brain natriuretic peptide levels are associated with poorer prognosis in patients with pulmonary thromboembolism; but only malignancy emerged as an independent predictor of mortality.

Assessment of subendocardial contractile function in aortic stenosis: a study using speckle tracking echocardiography

BACKGROUND

Angina and an electrocardiographic strain pattern are potential manifestations of subendocardial ischemia in aortic stenosis (AS). Left ventricular (LV) twist is known to increase proportionally to the severity of AS, which may be a result of loss of the inhibiting effect of the subendocardial fibers due to subendocardial dysfunction. It has also been shown that the ratio of LV twist to circumferential shortening of the endocardium (twist-to-shortening ratio [TSR]) is a reliable parameter of subendocardial dysfunction. The aim of this study was to investigate whether these markers are increased in AS patients with angina and/or electrocardiographic strain.

METHODS

The study comprised 60 AS patients with an aortic valve area <2.0 cm(2) and LV ejection fraction >50%, and 30 healthy-for age and gender matched-control subjects. LV rotation parameters were determined by speckle tracking echocardiography.

RESULTS

Comparison of patients without angina and strain (n = 22), with either angina or strain (n = 28), and with both angina and strain (n = 8), showed highest peak systolic LV apical rotation, peak systolic LV twist, and TSR, in patients with more signs of subendocardial ischemia. In a multivariate linear regression model, only severity of AS and the presence of angina and/or strain could be identified as independent predictors of peak systolic LV twist and TSR.

CONCLUSIONS

Peak systolic LV twist and TSR are increased in AS patients and related to the severity of AS and symptoms (angina) or electrocardiographic signs (strain) compatible with subendocardial ischemia.

Global longitudinal strain in relation to the severity of aortic stenosis: a two-dimensional speckle-tracking study

BACKGROUND

Global longitudinal strain (GLS) measured by two-dimensional speckle tracking imaging (2D-STI) has been shown to be useful for assessing subtle change in left ventricular function in severe aortic stenosis (AS) patients with preserved left ventricular ejection fraction (LVEF). However, there is little information about the relation between the progression of AS and changes in GLS. The aim of this study was to evaluate the relation between the severity of valve stenosis and GLS measured by 2D-STI in AS patients with normal LVEF.

METHODS

We studied 113 AS patients (age, 73.3 ± 8.8 years; male, 38%; aortic valve area (AVA), 1.0 ± 0.3 cm(2); mean pressure gradient (PG), 33.8 ± 22.1 mmHg) with normal LVEF (≥50%) but without overt coronary artery disease. Patients were stratified into three groups (mild, moderate and severe AS), and the clinical characteristics and echocardiographic findings were compared among the groups. Using dedicated software, we measured GLS in the apical four-chamber view.

RESULTS

LVEF was not significantly different among the three groups. However GLS showed significant differences in GLS among the three groups (mild: 17.1 ± 3.0%, moderate: 16.4 ± 3.0% and severe: 14.5 ± 3.9%, ANOVA P = 0.003). GLS was significantly correlated with AVA, mean PG, LVEF, LV mass index and early diastolic mitral annular velocity (e'). In multiple stepwise regression analysis, mean PG, LVEF and hypertension were independently associated with GLS (R(2) = 0.247, P = 0.0001).

CONCLUSIONS

Despite unchanged LVEF, GLS gradually decreased as severity of AS increases. GLS measured by 2D-STI might be useful to assess subtle changes in LV function in AS patients. 

Rationale, design and methodology for Intraventricular Pressure Gradients Study: a novel approach for ventricular filling assessment in normal and falling hearts

BACKGROUND

Intraventricular pressure gradients have been described between the base and the apex of the left ventricle during early diastolic ventricular filling, as well as, their increase after systolic and diastolic function improvement. Although, systolic gradients have also been observed, data are lacking on their magnitude and modulation during cardiac dysfunction. Furthermore, we know that segmental dysfunction interferes with the normal sequence of regional contraction and might be expected to alter the physiological intraventricular pressure gradients. The study hypothesis is that systolic and diastolic gradients, a marker of normal left ventricular function, may be related to physiological asynchrony between basal and apical myocardial segments and they can be attenuated, lost entirely, or even reversed when ventricular filling/emptying is impaired by regional acute ischemia or severe aortic stenosis.

METHODS/DESIGN

Animal Studies: Six rabbits will be completely instrumented to measuring apex to outflow-tract pressure gradient and apical and basal myocardial segments lengthening changes at basal, afterloaded and ischemic conditions. Afterload increase will be performed by abruptly narrowing or occluding the ascending aorta during the diastole and myocardial ischemia will be induced by left coronary artery ligation, after the first diagonal branch.Patient Studies: Patients between 65-80 years old (n = 12), both genders, with severe aortic stenosis referred for aortic valve replacement will be selected as eligible subjects. A high-fidelity pressure-volume catheter will be positioned through the ascending aorta across the aortic valve to measure apical and outflow-tract pressure before and after aortic valve replacement with a bioprosthesis. Peak and average intraventricular pressure gradients will be recorded as apical minus outflow-tract pressure and calculated during all diastolic and systolic phases of cardiac cycle.

DISCUSSION

We expect to validate the application of our method to obtain intraventricular pressure gradients in animals and patients and to promote a methodology to better understand the ventricular relaxation and filling and their correlation with systolic function.

Reduced global longitudinal strain in association to increased left ventricular mass in patients with aortic valve stenosis and normal ejection fraction: a hybrid study combining echocardiography and magnetic resonance imaging

Background

Increased muscle mass index of the left ventricle (LVMi) is an independent predictor for the development of symptoms in patients with asymptomatic aortic stenosis (AS). While the onset of clinical symptoms and left ventricular systolic dysfunction determines a poor prognosis, the standard echocardiographic evaluation of LV dysfunction, only based on measurements of the LV ejection fraction (EF), may be insufficient for an early assessment of imminent heart failure. Contrary, 2-dimensional speckle tracking (2DS) seems to be superior in detecting subtle changes in myocardial function. The aim of the study was to assess these LV function deteriorations with global longitudinal strain (GLS) analysis and the relations to LVMi in patients with AS and normal EF.

Methods

50 patients with moderate to severe AS and 31 controls were enrolled. All patients underwent echocardiography, including 2DS imaging. LVMi measures were performed with magnetic resonance imaging in 38 patients with AS and indexed for body surface area.

Results

The total group of patients with AST showed a GLS of -15,2 ± 3,6% while the control group reached -19,5 ± 2,7% (p < 0,001). By splitting the group with AS in normal, moderate and severe increased LVMi, the GLS was -17,0 ± 2,6%, -13,2 ± 3,8% and -12,4 ± 2,9%, respectively (p = 0,001), where LVMi and GLS showed a significant correlation (r = 0,6, p < 0,001).

Conclusions

In conclusion, increased LVMi is reflected in abnormalities of GLS and the proportion of GLS impairment depends on the extent of LV hypertrophy. Therefore, simultaneous measurement of LVMi and GLS might be useful to identify patients at high risk for transition into heart failure who would benefit from aortic valve replacement irrespectively of LV EF.

Left ventricular twist and untwist in aortic stenosis

BACKGROUND

To optimally exploit the potential added diagnostic and prognostic value of new left ventricular (LV) deformation parameters, better understanding of LV mechanics in aortic stenosis (AS) is warranted. We sought to determine a broad spectrum of LV rotation parameters in AS patients and age-matched healthy controls, in order to gain insight into the mechanical properties of the LV in AS.

METHODS

The study comprised 48 AS patients with an aortic valve area<2.0 cm2 and LV ejection fraction>50%, and 24 healthy--for age and gender matched--control subjects. LV peak systolic rotation (Rotmax), LV peak systolic twist (Twistmax), untwisting rate (mean diastolic untwisting velocity from Twistmax to mitral valve opening), peak diastolic untwisting velocity, and time-to-peak diastolic untwisting velocity were determined by speckle tracking echocardiography.

RESULTS

AS patients had normal basal Rotmax and increased apical Rotmax, resulting in increased Twistmax (13.4±4.0° vs. 11.4±2.7°, P<0.05). Apical Rotmax and Twistmax correlated significantly to echo-Doppler indicators of AS severity. Time-to-peak diastolic untwisting velocity was increased (20±10% vs. 15±9%, P<0.05) and untwisting rate was decreased (-38±21°/s vs. -50±28°/s, P<0.01) in AS patients.

CONCLUSIONS

Twistmax increases proportionally to the severity of AS, which might serve as a compensatory mechanism to maintain systolic LV function. LV diastolic untwisting is delayed and the untwisting rate is reduced in AS.

Size-adjusted left ventricular outflow tract diameter reference values: a safeguard for the evaluation of the severity of aortic stenosis

OBJECTIVE

We sought to evaluate the relationship among left ventricular outflow tract diameter (LVOTd), gender, and body surface area (BSA) and to evaluate the usefulness of size-adjusted LVOTd reference values in patients with aortic stenosis (AS). AS grading is based on the echocardiographic calculation of the aortic valve area (AVA) and requires LVOTd measurements, one main potential source of error. Transesophageal echocardiography (TEE) is reputed to be more accurate than transthoracic echocardiography (TTE), but validation studies are rare. A safeguard for LVOTd measurements is thus desirable.

METHODS

Since January 2006, 3 subsets of patients have been prospectively and concurrently enrolled: 1) TEE group: In 120 patients with and without AS, we prospectively measured LVOTd during both TTE and TEE. 2) Validation set: In 382 patients without aortic valve or ascending aorta diseases, we evaluated the relationship among LVOTd, gender, and BSA. 3) Testing set: In 173 patients with AS, we compared the AVA obtained using measured LVOTd (AVA(MEAS)) and calculated LVOTd derived from a regression determined in the validation set (AVA(CALC)).

RESULTS

TTE did not differ from and correlated well with TEE measurements overall (23 +/- 2 mm vs 23 +/- 2 mm, P = .26; r = 0.95, P < .0001) and in patients with AS (N = 43) (24 +/- 2 mm vs 24 +/- 3 mm, P = .15; r = 0.92, P < .0001). LVOTd was linearly correlated to BSA independently of gender (LVOTd = 5.7 * BSA+12.1; r = 0.55, P < .0001). In the testing set, AVA(CALC) did not differ from and correlated well with AVA(MEAS) (1.20 +/- 0.42 cm2 vs 1.23 +/- 0.40 cm2; P = .08; r = 0.89; P < .0001).

CONCLUSION

TTE and TEE measurements of the LVOTd provided similar results. LVOTd was significantly associated to BSA and LVOTd, derived from a linear regression linked to BSA independently of gender, provided an acceptable approximation of the AVA. Thus, although accurate measurement of LVOTd is a crucial part of the echocardiographic evaluation of AS severity, the present equation may be used as a safeguard when this measurement is difficult or not possible with TTE.