Clinical Investigation
Echocardiography in Valvular Heart Diseases
Poor Survival with Impaired Valvular Hemodynamics After Aortic Valve Replacement: The National Echo Database Australia Study

https://doi.org/10.1016/j.echo.2020.04.024Get rights and content

Highlights

  • AVR haemodynamics were assessed from the National Echo Database of Australia.

  • Mild, moderate, or severely impaired valvular hemodynamics (IVH) were examined.

  • 5-year mortality was similar for normal haemodynamics and mild IVH.

  • 5-year mortality was 45.5% for moderate IVH and 57.3% for severe IVH.

  • A mean gradient mortality threshold of 22.5 mm Hg was similar to native valve AS.

Background

There are limited data to describe the relationship between the transvalvular gradient and mortality among patients who undergo aortic valve replacement.

Methods

Using the National Echo Database Australia, valvular hemodynamics were characterized in 3,943 men (mean age, 62 ± 18 years) and 2,107 women (mean age, 62 ± 19 years) who underwent aortic valve replacement (median follow-up duration, 770 days; interquartile range, 381–1,584 days). The degree of impaired valvular hemodynamics (IVH) was categorized as mild (mean gradient 10.0–19.9 mm Hg, peak velocity 2.0–2.9 m/sec), moderate (mean gradient 20.0–39.9 mm Hg, peak velocity 3.0–3.9 m/sec), or severe (mean gradient ≥ 40.0 mm Hg, peak velocity ≥ 4 m/sec or effective orifice area < 0.8 cm2).

Results

Overall, 2,175 (36.0%), 2,598 (42.9%), 698 (11.5%), and 579 (9.6%) patients had no, mild, moderate, and severe IVH, respectively. Those with residual moderate or severe IVH had 5-year mortality of 45.5% and 57.3%, respectively, and higher adjusted long-term all-cause mortality (adjusted hazard ratios, 1.44 and 2.02; P < .001) compared with “no IVH.” Patients with mild IVH had similar mortality rates to those without IVH. A mortality threshold was evident above a mean transvalvular gradient >22.5 mm Hg after adjusting for age, sex, stroke volume index, aortic regurgitation, and effective orifice area.

Conclusions

After aortic valve replacement, most patients displayed an acceptable aortic valve hemodynamic profile. Moderate to severe IVH, however, was associated with poor long-term survival, with a threshold for increased mortality similar to that of native valvular aortic stenosis evident.

Section snippets

Study Hypotheses

We used the National Echo Database Australia (NEDA), with its capacity to individually link echocardiographic findings with long-term mortality in a large patient population.12 We first hypothesized that a prospective analysis of short- and long-term survival outcomes (including 1- and 5-year actual survival) according to residual IVH (applying the same thresholds to characterize severity of AS in those with native AVs)9,13 would confirm a gradient of increasing risk with respect to all-cause

Study Setting and Design

As described previously in our original report,12 and two recent analyses of the prognostic implications of pulmonary hypertension14 and native valve AS,8 respectively, NEDA is a very large observational registry that captures individual echocardiographic data (combined with basic demographic profiling) on a retrospective and prospective basis from participating centers throughout Australia (https://www.neda.net.au/participating-sites/). At the time of study census, a total of 12 centers had

Cohort Profile

Table 1 summarizes the broad demographic and echocardiographic characteristics of the study cohort categorized by clinical severity, comprising 3,943 men (mean age, 69 ± 16 years) and 2,107 women (mean age, 71 ± 16 years; P < .001 for age comparison). Of these, 769 (13%) underwent multiple (valve-in-valve or redo valve replacement) procedures. Overall, of the 6,050 patients, AVR function was normal (no IVH) in a total of 2,175 (36.0%; 95% CI, 34.8%–37.2%), mild IVH was seen in 2,598 (42.9%; 95%

Discussion

To our knowledge, this is the largest ever analysis of survival across the full spectrum of IVH among patients who underwent AVR, demonstrating high rates of mortality in both moderate and severe IVH when applying thresholds from current guidelines on native valvular AS.9 After adjusting for age, sex, and other potential confounders (including concurrent LV dysfunction and high- and low-flow states), those with moderate or greater IVH had a high short- and long-term risk for death (Figure 5).

Conclusion

In a very large cohort of patients who underwent prior AVR, we examined long-term survival across the spectrum of IVH and demonstrated that even moderate IVH was associated with increased rates of mortality. Importantly, the increased mortality is independent of EOA or the effects of pressure recovery. As such, we confirm that increased flow gradients across an AVR are not benign, following a similar mortality trajectory to moderate and severe native valvular AS, with a critical threshold for

Acknowledgments

We acknowledge the investigators from the NEDA contributing sites (http://www.neda.net.au/participating-sites). We gratefully acknowledge the intellectual contributions of Susan Strange in framing the concept and the term “impaired valvular hemodynamics.”

References (28)

  • S.R. Kapadia et al.

    5-Year outcomes of transcatheter aortic valve replacement compared with standard treatment for patients with inoperable aortic stenosis (PARTNER 1): a randomised controlled trial

    Lancet

    (2015)
  • N. Hanayama et al.

    Patient prosthesis mismatch is rare after aortic valve replacement: valve size may be irrelevant

    Ann Thorac Surg

    (2002)
  • E. Permanyer et al.

    St. Jude Medical Trifecta aortic valve perioperative performance in 200 patients

    Interact Cardiovasc Thorac Surg

    (2013)
  • R. Yanagisawa et al.

    Early and late leaflet thrombosis after transcatheter aortic valve replacement

    Circ Cardiovasc Interv

    (2019)
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    NEDA was originally established with funding support from Actelion Australia Pharmaceuticals, Bayer Pharmaceuticals, and GlaxoSmithKline. Both NEDA (1055214) and Dr. Stewart (11358940) are supported by the National Health and Medical Research Council of Australia.

    Conflicts of Interest: None.

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