Left Ventricular Diastolic Filling Pressures During Dobutamine Stress Echocardiography: Relationship to Symptoms and Ischemia

Additional roles of diastolic parameters in the diagnosis of obstructive coronary artery disease

BACKGROUND

A recent guideline emphasizes the role of four indicators, including annular e´ velocity, E/e´, left atrial (LA) size, and peak tricuspid regurgitation (TR) velocity, in the assessment of left ventricular (LV) diastolic dysfunction. This study was performed to determine the relationships among these four parameters and obstructive coronary artery disease (CAD).

METHODS

The study data were obtained from a nation-wide registry, composed of 1307 patients (age, 60.4 ± 10.8 years; 964 women) with normal LV ejection fraction (LVEF) who underwent invasive coronary angiography in the suspicion of CAD. Septal e´, E/e´, LA dimension (LAd), and TR velocity were assessed by transthoracic echocardiography.

RESULTS

Compared with patients without obstructive CAD, those with obstructive CAD showed changes in diastolic parameters indicating more progressed LV diastolic dysfunction in univariate analyses. In multiple logistic regression analysis, low septal e´ velocity (<7 cm/s) was identified as an independent risk factor associated with obstructive CAD (odd ratio, 1.91; 95% confidence interval, 1.08-3.36; P = 0.026). Receiver-operating characteristic curve analysis showed that septal e´ velocity had the most powerful value in the detection of obstructive CAD than the other three diastolic parameters (P < 0.01 for each comparison). Septal e´ velocity significantly increased diagnostic value of treadmill exercise test (TET) in the detection of obstructive CAD (P < 0.001 for integrated discrimination improvement index).

CONCLUSIONS

Among the four diastolic parameters, septal e´ velocity had the most powerful relationship with obstructive CAD in stable patients with normal LVEF. The addition of septal e´ velocity could improve the diagnostic value of TET.

Left Atrial Strain in Evaluation of Heart Failure with Preserved Ejection Fraction

BACKGROUND

Patients with heart failure with preserved ejection fraction (HFpEF) may have elevated left ventricular filling pressure with exercise (LVFP-ex), despite normal LVFP at rest. The aim of this study was to assess the diagnostic value of resting left atrial strain (LAS) in detecting elevated LVFP-ex in patients with dyspnea evaluated on exercise stress echocardiography.

METHODS

Two-dimensional speckle-tracking analysis for LAS was performed in 669 consecutive patients (mean age, 64 ± 14 years; 53% men) who underwent treadmill echocardiographic evaluation and had left ventricular ejection fractions ≥ 50%. Assessment of LVFP at rest LVFP-ex was based on the 2016 American Society of Echocardiography guidelines for diastolic function assessment. An E/e' ratio ≥ 15 after exercise is considered to indicate elevated LVFP-ex. A continuous diagnostic score of HFpEF was calculated on the basis of the European Society of Cardiology HFA-PEFF diagnostic algorithm.

RESULTS

LAS_reservoir was lowest in patients with elevated LVFP at rest (n = 81) and lower in those with normal resting filling pressure who developed elevated LVFP-ex (n = 108) compared with those who maintained normal LVFP-ex (29.0 ± 5.2% vs 33.1 ± 5.0% vs 39.3 ± 4.8%, P < .001). Lower LAS_reservoir was associated with worse exercise capacity as assessed by metabolic equivalents, exercise time, and functional aerobic capacity (multivariate-adjusted P values all < .05). In patients with normal or indeterminate LVFP at rest (n = 587), LAS_reservoir and preexercise HFA-PEFF score demonstrated areas under the curve of 0.82 and 0.7, respectively, for elevated LVFP-ex. There were 28% higher odds of developing elevated LVFP-ex per 1% decrease in LAS_reservoir (odds ratio, 0.78; 95% CI, 0.74-0.82). Among patients with intermediate scores (n = 461), 123 developed elevations in LVFP-ex and were classified as having HFpEF per the diagnostic algorithm. The addition of LAS_reservoir improved the diagnostic value of HFA-PEFF score for HFpEF (area under the curve increased from 0.71 to 0.80, P = .01).

CONCLUSIONS

LAS_reservoir has potential to identify patients with intermediate scores for HFpEF who may develop elevated LVFP-ex only and is therefore a promising alternative to aid in diagnosis when exercise testing is not feasible.

Hemodynamic Validation of the E/e' Ratio as a Measure of Left Ventricular Filling Pressure in Patients With Non-ST Elevation Myocardial Infarction

The E/e' ratio has an established role in the assessment of left ventricular filling pressure (LVFP) in stable patients, but its accuracy in acute myocardial ischemia is less well established. The aim of this study was to validate the relation between the E/e' ratio and invasively measured LVFP in patients with non-ST elevation myocardial infarction (NSTEMI). A total of 120 unselected patients with NSTEMI underwent cardiac catheterization with measurement of left ventricular end-diastolic pressure (LVEDP; elevated ≥15 mm Hg) and Doppler echocardiography with either simultaneous (n = 30) or same-day (n = 90) measurement of E/e'. Patients were aged 64.1 ± 11.8 years, 72% were male and mean left ventricular ejection fraction was 48.0 ± 20.9%. Septal, lateral, and average E/e' ratios all showed a significant correlation with LVEDP (Pearson's r: 0.42, 0.43, 0.48, respectively [all p <0.001]). Receiver operating characteristics curves showed an area under the curve of 0.72, 0.72, and 0.75 (all p <0.001) for septal, lateral, and average E/e', respectively. The sensitivity, specificity, positive (PPV), and negative (NPV) predictive values for the guideline-recommended threshold of average E/e' >14 for elevated LVEDP was 27%, 93%, 79%, and 44%, respectively. Utilizing lower E/e' boundaries of 6, 7, and 8 for lateral, average, and medial E/e', respectively, improved the NPV to ≥80% for each parameter. In conclusion, the E/e' ratio is a robust measure of LVFP during acute NSTEMI using upper and lower thresholds to achieve a high PPV and NPV, respectively, with the use of adjunctive guideline-recommend measures required in patients with nonconclusive E/e'.

Stress-induced Worsening of Left Ventricular Diastolic Function as a Marker of Myocardial Ischemia

Background:

Echocardiography has been the subject of interest in diagnosing diastolic dysfunction and estimating left ventricular filling pressures (LVFPs). The present study is set to estimate the correlation between the worsening of diastolic parameters and the evidence of inducible ischemia during an exercise stress echocardiography (SE) in comparison with the results of coronary computed tomographic angiogram (CCTA).

Methods:

A total of 191 consecutive patients from the executive screening program who underwent exercise SE followed by CCTA were evaluated. Baseline demographics, heart rate, and blood pressure measurements were extracted for analysis. Standard two-dimensional and tissue Doppler imaging parameters were analyzed. Diastolic function was graded at rest and peak exercise.

Results:

Patients who had worsening of diastolic function by at least one grade had had 2–3-fold higher odds of having abnormal SE. In addition, patients with worsening of diastolic function had higher stress LVFPs (E/e’ = 11.7 ± 2.7 vs. E/e’ 8.0 ± 2.0; P < 0.0001), more E/e’ change >25% (48% vs. 22%, P = 0.012), and were more likely to have obstructive coronary artery disease (CAD) on CCTA (23.8% vs. 9.2%; P = 0.045). A change in E/e’ >25% (stress-rest) was highly associated with a positive stress test and abnormal CCTA result. Patients with no change or improvement in diastolic function with stress had a 92% negative predictive value of having normal SE and 91% of normal/nonobstructive CCTA.

Conclusion:

A worsening of diastolic function and a change in E/e’ >25% (stress-rest) were associated with abnormal SE, positive stress test, and obstructive CAD when compared to CCTA results.

Extent and severity of coronary artery disease by coronary CT angiography is associated with elevated left ventricular diastolic pressures and worsening diastolic function

BACKGROUND

Patients with flow-limiting coronary stenoses exhibit elevated left ventricular end-diastolic pressure (LVEDP) and abnormal left ventricular (LV) relaxation.

OBJECTIVE

We investigated the relationship of extent and severity of coronary artery disease (CAD) by coronary CT angiography (CTA) to LVEDP and measures of LV diastolic dysfunction.

METHODS

We identified consecutive patients undergoing coronary CTA and transthoracic echocardiography who were assessed for diastolic function. CAD was evaluated on a per-patient, per-vessel, and per-segment basis for intraluminal diameter stenosis by using an 18-segment model (0 = none, 1 = 1%-49%, 2 = 50%-69%, and 3 = 70%-100%) and summed over segments to obtain overall coronary plaque burden (segment stenosis score [SSS]; maximum = 54). Transthoracic echocardiography evaluated mitral inflow E wave-to-A wave ratio, tissue Doppler early mitral annual tissue velocity axial excursion, stage of diastolic dysfunction, and LV dimensions and estimated LVEDP from the ratio of mitral inflow velocity to early mitral annular (medial) tissue velocity.

RESULTS

Four hundred seventy-eight patients (57% women; mean age, 57.9 ± 14.6 years; 24.9% prior CAD) comprised the study population. Increasing per-patient maximal coronary stenosis, number of vessels with obstructive stenosis, and SSS were associated with increased LVEDP. The prevalence of advanced diastolic dysfunction increased with greater number of obstructive vessels. In multivariable analyses, SSS was associated with increased LVEDP (0.8 mm Hg per tertile increase in SSS, 0.5-1.1; P < .001); reduced E' axial excursion (-0.3; 95% confidence interval [CI], -0.5 to -0.1; P = .001), increased LV mass index (1.6 g/m(2) per tertile increase in SSS; P = .04), and increased relative wall thickness (0.005; 95% CI, 0.004-0.009; P = .03), with consistent relationships persisting even among persons with per-patient maximal stenosis <50% and LV ejection fraction ≥ 55%.

CONCLUSIONS

Extent and severity of obstructive as well as nonobstructive CAD by coronary CTA are associated with increased LVEDP and measures of diastolic dysfunction.

Do additional echocardiographic variables increase the accuracy of E/e' for predicting left ventricular filling pressure in normal ejection fraction? An echocardiographic and invasive hemodynamic study

BACKGROUND

There are few data on adding left atrial volume index (LAVi) or pulmonary artery systolic pressure (PAP) to the ratio of early mitral inflow to mitral annular velocity (E/e') for the estimation of left ventricular (LV) filling pressure in patients with preserved LV ejection fractions (LVEFs) (>50%).

METHODS

Patients underwent echocardiography within 20 minutes of cardiac catheterization. Echocardiographic variables were compared with invasively measured LV preatrial contraction pressure (pre-A).

RESULTS

Of the 122 patients studied (mean age, 55 +/- 9 years; mean LVEF, 61 +/- 6%), 67 (55%) were women, 108 (88%) had hypertension, and 79 (65%) had significant coronary artery disease at catheterization. E/e' was significantly correlated with pre-A (R = 0.63, P < .0001) compared with LAVi (R = 0.49, P < .001) and PAP (R = 0.48, P < .001). E/e' > 13 had sensitivity of 70% and specificity of 93% (area under the curve [AUC], 0.82; P < .0001), LAVi > 31 mL/m2 had sensitivity of 78% and specificity of 76% (AUC, 0.80, P < .001), and PAP > 28 mm Hg had sensitivity of 80% and specificity of 64% for pre-A > 15 mm Hg (AUC, 0.77, P < .001). Adding LAVi >31 mL/m2 for E/e' = 8 to 13 significantly increased the accuracy of E/e' > 13 alone (sensitivity, 87%; specificity, 88%; AUC, 0.89; P = .01 for comparison). However, adding PAP > 28 mm Hg for E/e' = 8 to 13 did not significantly increase the accuracy of E/e' > 13 alone (AUC, 0.82; sensitivity, 82%; specificity, 72%; P = NS for comparison).

CONCLUSIONS

In patients with preserved LVEFs, adding LAVi > 31 mL/m2 to E/e' (when E/e' was in the gray zone, but not when E/e' was >13) significantly increased the accuracy of E/e' alone for the estimation of LV filling pressure. These data support the notion of using several, rather than any single, Doppler echocardiographic parameter for the accurate assessment of LV diastolic function.

Prognostic Implications of Left Ventricular Filling Pressure With Exercise

Background— The estimation of left ventricular (LV) filling pressure from the ratio of transmitral and annular velocities (E/e′) after exercise echocardiography may identify diastolic dysfunction in patients who complain of exertional dyspnea. This study sought to determine the relative contributions of exercise E/e′ and ischemia to outcomes in patients referred for exercise echocardiography.

Methods and Results— Rest and exercise E/e′ were obtained in 522 patients referred for exercise echocardiography, who were followed for cardiovascular death and hospitalization over a median of 13.2 months. Exercise E/e′ >2 SD from normal was used to denote raised LV filling pressure with stress (n=75), and ischemia (n=250) was identified by inducible wall motion abnormalities. There were 65 cardiovascular hospitalizations during the follow-up period. Survival analysis showed patients without ischemia and with normal exercise E/e′ to have a better prognosis than those with ischemia, with or without raised exercise E/e′ ( P =0.003) and the outcomes of patients with isolated raised exercise E/e′ and isolated ischemia to be similar. Exercise E/e′ was most valuable in patients with normal resting E/e′; those with elevation with exercise had a worse outcome than those with normal exercise E/e′ ( P =0.014). Exercise capacity (hazard ratio, 0.893; P =0.008), exercise wall motion score index (hazard ratio, 1.507; P <0.001), and exercise E/e′ >14.5 (hazard ratio, 2.988; P =0.002) were independent predictors of outcome. The addition of exercise E/e′ to exercise capacity and wall motion score index resulted in an increment in model power to predict adverse outcome ( P =0.006).

Conclusions— Exercise E/e′ is associated with cardiovascular hospitalization, independent of and incremental to inducible ischemia.