Estimating pulmonary capillary wedge pressures using Doppler variables of early diastolic left ventricular inflow

Doppler-Derived Indexes and B-Type Natriuretic Peptide in Prediction of Paroxysmal Atrial Fibrillation in Essential Hypertension: A Prospective Study

BACKGROUND

Onset of atrial fibrillation in hypertensive patients is usually associated with a high occurrence of cardiovascular complications. Despite its leading importance as a highly prevalent and modifiable risk factor, only a few data are available regarding the predictors of paroxysmal atrial fibrillation (PAF) in hypertensive patients.

OBJECTIVES

This study was undertaken to determine if PAF could be predicted in hypertensive patients while in sinus rhythm using Doppler-derived indexes and the plasma B-type natriuretic peptide (BNP) concentration.

METHODS

We prospectively evaluated 165 consecutive patients with hypertension and no known history of PAF or cardiovascular events who attended the cardiology outpatient clinic. Their mean age was 62 +/- 12, 94 male, 71 female. The conventional echocardiographic parameters were measured including: left atrial (LA) volume, mitral regurgitation (MR), left ventricular (LV) function, LV mass. The ratio of transmitral peak E-wave velocity to flow propagation velocity (E/V(p)), ratio of E-wave to mitral annular early diastolic velocity (E/E(a)) obtained by Doppler tissue at the lateral and septal corners of the mitral annulus were calculated. The plasma BNP was measured at the study entry.

RESULTS

After a mean follow-up of 15 +/- 3 months, PAF (symptomatic attacks or documented on the ECG) occurred in 36 (21.8%) of 165 patients. The patients with PAF had significant higher BNP levels than those with sinus rhythm (160 +/- 109.8 vs. 87.9 +/- 57.7 pg/ml, P < 0.001) Also, E/E(a) and E/V(p) ratios were significantly higher in hypertensives with PAF (15.1 +/- 2.8 vs. 8.39 +/- 1.33, P < 0.001), and (1.65 +/- 1.29 vs. 1.19 +/- 1.06, P < 0.001) respectively. In univariate analysis, E/V(p), E/E(a), and BNP and LV hypertrophy were significant predictors of PAF. Barely E/V(p) and E/E(a) remained independently significant after adjustment of clinical and other echocardiographic variables by multivariate logistic regression analysis (odd ratio: 3.36, P < 0.001 and 4.93, P < 0.001 respectively). A cutoff value of > or =1.7 for E/V(p) predicted PAF with 91% sensitivity and 88% specificity; E/E(a) >12 has sensitivity 98%, specificity 89%, while BNP>170 pg/ml has 83% and 72% specificity, respectively, for prediction of PAF in hypertensive patients.

CONCLUSION

Paroxysmal atrial fibrillation could be predicted in hypertensive patients while in sinus rhythm using Doppler-derived indexes. Increased E/V(p), E/E(a) ratios and elevated BNP appear to be useful parameters to identify patients at heightened risk. They may reflect early left ventricular dysfunction and atrial hypertension in this population.

Comparative value of tissue Doppler imaging and m-mode color Doppler mitral flow propagation velocity for the evaluation of left ventricular filling pressure

BACKGROUND

Recently, two new indexes based on the ratio of transmitral early diastolic velocity (E) to tissue Doppler imaging (TDI), and early diastolic velocity of mitral annulus (E') and E to propagation velocity (Vp) have been proposed to predict left ventricular (LV) filling pressures. However, little is known about the comparative value of these two indexes.

METHODS

We studied 71 consecutive patients referred for coronary angiography (mean age +/- SD, 65 + 11 years; 21 patients with LV ejection fraction [EF] < 50%). Complete Doppler echocardiographic examination including TDI and Vp measurements and direct measurement of LV end-diastolic pressure (LVEDP) were performed simultaneously in the catheterization laboratory. LV filling pressures were considered elevated when LVEDP was > or = 15 mm Hg.

RESULTS

The correlation coefficients between E/E' and E/Vp and LVEDP were 0.68 (p = 0.01) and 0.54 (p = 0.01), respectively, in the overall population. The correlations were better in patients with low LV EF (< 50%) [0.8 (p = 0.01) and 0.77(p = 0.01)] and poor in patients with normal LV EF (0.57 [p = 0.05] and 0.41 [not significant]), respectively. Moreover, Vp measurements had higher interobserver variability compared to E' (14% vs 7%). The cutoff values for both indexes giving the best sensitivity and specificity in identifying LVEDP > or = 15 mm Hg were 9 for (E/E') and 2 for (E/Vp).

CONCLUSION

Both E/E' and E/Vp can be used for the evaluation of LV filling pressures. However, the sensitivity of these indexes, especially E/Vp, is hampered by EF. E/E' has a lower variability than Vp and should be preferred for estimation of filling pressures especially in patients with EF > 50%.

Is the Ratio of Transmitral Peak E-Wave Velocity to Color Flow Propagation Velocity Useful for Evaluating the Severity of Heart Failure in Atrial Fibrillation?

BACKGROUND

Although analysis of the transmitral inflow (TMF) pattern is widely used for evaluating left ventricular diastolic function and provides valuable information for the management of heart failure (HF) in sinus rhythm, its utility in patients with atrial fibrillation (AF) has not been established. The aim of this study was to investigate the relationship between the ratio of transmitral peak E-wave velocity to flow propagation velocity (E/Vp) obtained by a newly developed dual Doppler system and the plasma B-type natriuretic peptide (BNP) concentration or pulmonary capillary wedge pressure (PCWP) for evaluating the severity of heart failure with AF.

METHODS AND RESULTS

In 68 patients with AF, the E/Vp was compared with plasma BNP concentration and PCWP. A cutoff value of > or =1.7 for E/Vp predicted a plasma BNP concentrationl of > or =200 pg/ml, with 80% sensitivity and 84% specificity. Only E/Vp was found to be independently significant by stepwise multilinear regression analysis (r=0.40, p=0.01). PCWP values had good correlation with E/Vp (r=0.63, p<0.01) and were significantly higher in the group with E/Vp >/=1.7 (16+/-6 mmHg vs 11+/-4 mmHg, p<0.05).

CONCLUSION

The Doppler-derived index of E/Vp correlated well with the neurohormonal and hemodynamic parameters, and was useful for evaluating the severity of heart failure with AF.