Assessment of left ventricular filling pressure: left atrial reservoir strain is an excellent replacement for missing tricuspid regurgitation velocity

Background

When evaluating left ventricular filling pressure (LVFP) according to current guidelines, tricuspid regurgitation (TR) velocity is often not available.

Purpose

In the present study we investigate if left atrial (LA) reservoir strain may be used instead of TR velocity for evaluation of LVFP.

Methods

We performed a prospective, multicenter, multinational and multivendor study in an all comer population of 322 patients with suspected heart failure or other cardiovascular disease where LVFP was measured by right- or left heart catheterization, as pulmonary capillary wedge pressure or pre-A LV diastolic pressure, respectively. Echocardiography was performed within 1 day of catheterization.

101 patients classified as special populations in the 2016 ASE/EACVI recommendations (i.e. non-cardiac pulmonary hypertension, atrial fibrillation, hypertrophic and restrictive cardiomyopathies) were excluded. Of the remaining 221 patients, 118 patients had EF ≥50% and 103 patients had EF <50%. Regression analysis was performed for LA reservoir strain and TR velocity against LVFP. LA reservoir strain at a cut-off value of <18% was applied instead of TR velocity in the 2016 ASE/EACVI algorithm and compared with the current algorithm.

Results

LA reservoir strain correlated better with LVFP than TR velocity, r=0.62 vs 0.40 (p<0.01) (Figure 1). When replacing TR velocity with LA reservoir strain, the feasibility of the ASE/EACVI 2016 algorithm increased from 91.8% to 98.1%. The accuracy of the algorithm was not significantly altered (80% vs 79%).

An accuracy of 80% for the algorithm is lower than what has been reported in earlier publications, this may be due to inclusion of patients without suspected heart failure and no assessment of clinical data, which in turn may have influenced the accuracy of the algorithm.

Conclusion

LA reservoir strain has better correlation to LVFP than TR velocity, and can be used in the ASE/EACVI 2016 algorithm for estimation of LVFP as a replacement when TR velocity is missing.

Funding Acknowledgement

Type of funding source: Public Institution(s). Main funding source(s): South-Eastern Norway Regional Health Authority

Which single echo parameter is the best marker of left ventricular filling pressure?

Background

Estimation of left ventricular filling pressure (LVFP) is highly relevant in clinical practice. Invasive pressure remains the gold standard, but a number of echocardiographic parameters that correlate with LVFP are used as non-invasive markers of pressure.

Purpose

We investigated how different echocardiographic parameters correlated with invasively measured LVFP, and how accurately those parameters could differentiate between normal or elevated LVFP.

Method

We performed a prospective, multicenter, multinational and multivendor study in an all comer population of 322 patients with suspected heart failure or other cardiovascular disease. 194 patients had EF ≥50% and 129 had EF <50%. LVFP was measured by right- or left heart catheterization, as pulmonary capillary wedge pressure or pre-A LV diastolic pressure, respectively.

When excluding all special patient populations defined in the 2016 recommendations for echocardiographic evaluation of LV diastolic function, 213 patients remained. Of these 135 had EF ≥50% and 74 had EF <50%.

Echocardiography was performed within 1 day of catheterization. Previously recommended cut-off values for established parameters were used to determine the accuracy of classifying LVFP as normal or elevated. For left atrial (LA) reservoir strain, based on ROC analysis, a cut-off value of <18% was used as marker of elevated LVFP.

Results

LA reservoir strain and the ratio of peak mitral early flow velocity (E) and LA reservoir strain (E/LA strain) showed the best correlations to LVFP (Table 1, Figure 1). They also had the highest accuracy, 75% for both, in classifying LVFP as normal or elevated in the whole patient population. E/LA reservoir strain provided no additional diagnostic value to using LA reservoir strain alone.

In HFpEF patients accuracy was essentially similar for LA strain, E/LA strain and E/e', whereas in HFrEF patients the two former tended to be better than E/e'.

Conclusion

Parameters containing LA reservoir strain showed the best correlation to LVFP. This indicates that LA reservoir strain may have a role in evaluation of LVFP.

Funding Acknowledgement

Type of funding source: Public Institution(s). Main funding source(s): South-Eastern Norway Regional Health Authority

A pilot safety trial of prolonged (48 h) infusion of the dual endothelin-receptor antagonist tezosentan in patients with advanced heart failure

STUDY OBJECTIVES

Tezosentan, an IV dual endothelin-receptor antagonist, has demonstrated beneficial hemodynamic effects in patients with advanced heart failure. In addition, no notable differences in safety and tolerability variables were detected between tezosentan-treated and placebo-treated patients when infused over 4 to 6 h. The present study was conducted primarily to assess the safety and tolerability of tezosentan when administered over a prolonged, 48-h treatment period, and secondarily to investigate hemodynamic response.

DESIGN

This randomized, double-blind, active-controlled study of continual IV administration of two dosages of tezosentan (20 mg/h and 50 mg/h; n = 6 each) or dobutamine (5 microg/kg/min; n = 2) over 48 h in patients with advanced heart failure was conducted to assess tolerability, safety, and hemodynamic variables (Doppler echocardiography).

RESULTS

During tezosentan infusion, no episodes of hypotension requiring withdrawal of therapy occurred, and hemodynamic rebound was not observed after abrupt cessation of the infusion. There were no reports of worsening heart failure in tezosentan-treated patients up to 28 days following the infusion. The most common side effect during the infusion was headache (9 of 12 tezosentan-treated patients and both dobutamine-treated patients). Echocardiographic Doppler measurements suggested improvements in cardiac index, pulmonary capillary wedge pressure, and relaxation properties as well as in diastolic and systolic function in all treatment groups.

CONCLUSIONS

Prolonged, 48-h IV dual endothelin-receptor antagonism with tezosentan was well tolerated with no new safety concerns emerging. These data further support the potential role of tezosentan in the treatment of patients with acute heart failure.

Comparison of global and regional left ventricular function assessed by gated-SPECT and 2-D echocardiography

Left ventricular (LV) function and volumes have major diagnostic and prognostic importance in patients with heart diseases. Those measurements are most commonly obtained with echocardiographic techniques. Recently, with the use of electrocardiographic gating during the acquisition of myocardial perfusion scintigraphy, it has become possible to simultaneously assess LV perfusion, function and volumes. Both technetium-99m labeled agents and thallium-201, the most commonly used tracers for perfusion scintigraphy, can be used for gated perfusion purposes. Many authors compared gated perfusion images to echocardiography, in regard to LV global and segmental wall motion as well as volumes. We performed gated single photon emission computed tomography (SPECT) and echocardiography in 109 consecutive patients (53 male, 56 female, mean age 63 +/- 14 years) within 15 days of each other. Gated tomographic data, including LV volumes, LV ejection fraction and segmental wall motion, were processed using an automatic algorithm whereas echocardiography used standard techniques. To obtain interobserver and intraobserver variability of regional wall motion, we randomly re-analyzed 34 of the 109 gated SPECT studies. The correlations between gated tomography and echocardiography with respect to end-diastolic volume, end-systolic volume and left ventricular ejection fraction were good to excellent (all p < 0.001, r values > or = 0.68) regardless of the use of post-stress or rest/redistribution images, thallium-201 or technetium-99m tracers. The agreement between both techniques, regarding segmental wall motion analysis were also good. Intraobserver and interobserver variability for regional wall motion were good to excellent, with an agreement of 90% and 88%, respectively. Other authors also had similar results in different studies with different populations, tracers, imaging acquisition and processing protocols. Thus, quantitative gated SPECT, using a variety of protocols and with either Tl-201 or Tc-99m tracers, has a good correlation with echocardiography for the measurements of absolute LV volumes and LV global and regional function. This technique is highly reproducible and can be used clinically for those measurements, with the additional advantage that the ventricular performance parameters are obtained from the perfusion images. Furthermore, contrary to echocardiographic techniques used to assess LV volumes and LV function, which are quite labor intensive and more observer-dependent, the gated SPECT technique is nearly totally automatic, and highly reproducible.