Impact of catheter ablation on HFpEF in people with comorbid atrial fibrillation and HFpEF using invasive haemodynamic testing

Background

The impact of catheter ablation (CA) for atrial fibrillation (AF) in patients with heart failure with preserved ejection fraction (HFpEF) is unknown.

Objectives

To determine whether CA for AF reverses adverse haemodynamic changes associated with HFpEF.

Methods

Consecutive consenting patients with EF ≥50% scheduled for index CA underwent baseline exercise right heart catheterisation (exRHC), cardiac output (CO) measurement, cardiac MRI, echocardiogram, QOL questionnaires and BNP testing. HFpEF was defined by resting pulmonary capillary wedge pressure (PCWP) ≥15mmHg or peak exercise PCWP ≥25 mmHg during exRHC. Patients with HFpEF were offered follow-up exRHC ≥6 months post-CA.

Results

Of 252 patients scheduled for CA between April 2017 and Sept 2019, 131 (51.9%) qualified for inclusion, 65 (49.6%) consented to exRHC and 11 (16.9%) were excluded due to a subsequent decrease in EF (10) and uncontrolled hypertension (1). Fifty-four underwent exRHC, with 35 (65%) meeting criteria for HFpEF. Of them 26 (74.3%) who underwent CA, 20 (77%) had a follow up exRHC at 12±6 months follow-up, showing an overall decrease in peak exercise PCWP from 30.3±4.2 to 26.8±4.7 mmHg (p<0.05). Patients without arrhythmia recurrence showed significant improvements in peak exercise PCWP (29.2±3.7 to 22.9±2.0 mmHg (p<0.01). Their cardiac output increased from 10.3±3.0 to 12.1±4.0 mmHg p=0.1), and BNP decreased from (94.6±101.6 to 38.0±34.0 mmHg (p=0.06),whereas those with arrhythmia recurrence did not. Overall, 9 patients (45.0%) no longer met criteria for HFpEF.

Conclusion

There is a high prevalence of HFpEF in people referred for AF ablation. Successful CA for AF reverses the adverse haemodynamic changes associated with HFpEF

Changes in PCWP following AF ablation

Funding Acknowledgement

Type of funding source: Public grant(s) – National budget only. Main funding source(s): NHMRC, NHF, RACP

130The effect of parity on exercise physiology in women with heart failure with preserved ejection fraction

Introduction

Women are overrepresented amongst patients with HFpEF, however the underpinning mechanism for this asymmetric distribution is unclear. Pregnancy has been demonstrated to contribute to cardiovascular risk, and represents a potential gender specific risk factor for HFpEF.

Purpose

To investigate the relationship between parity and severity of HFpEF on invasive haemodynamic and echocardiographic studies.

Methods

Patients referred for investigation of dyspnoea with exercise right heart catheterisation from 2008–19 were included and classified as HFpEF with an ejection fraction (EF) ≥50% and a resting PCWP ≥15mmHg or exercise PCWP ≥25mmHg. All patients underwent detailed haemodynamic and echocardiographic assessment, and an obstetric history including socioeconomic data were obtained using a questionnaire.

Results

58 women were included, and categorised as having either 0–2 births, or ≥3 births, dividing the cohort equally. Women with ≥3 births achieved a lower peak exercise workload than those with 0–2 births (46 [31–68] vs. 38 [24–51] W, p=0.04). Women with ≥3 births had a greater rise in pulmonary capillary wedge pressure indexed to workload with exercise (0.5 [0.3–0.8] vs. 0.3 [0.2–0.5] mmHg/W, p=0.03), paralleled by a greater rise in right atrial pressure (10 [8–12] vs. 7 [3–11] mmHg, p=0.01), pictured. Pulmonary vascular resistance was also higher in women with ≥3 births (1.9 [1.6–2.4] vs. 1.6 [1.4–1.9] mmHg/L/min rest, p=0.046, and 1.9 [2.4–2.4] vs. 1.4 [1–1.8] mmHg/L/min exercise, p=0.024). Left ventricular ejection fraction was lower at rest (60 [57–61] vs. 63 [60–66] %, p=0.008) and during exercise (65 [62–67] vs. 68 [66–70] %, p=0.038) in women with higher parity. Otherwise, echocardiographic parameters did not differ according to parity. There were no significant differences between parity groups in baseline characteristics, including age, body mass index, systemic blood pressure, natriuretic peptides or dyspnea class. Similarly, comorbidities and socioeconomic status did not differ.

Conclusion(s)

Higher parity is associated with impairments in multiple physiologic parameters of HFpEF severity in women, including diastolic reserve, pulmonary vascular resistance, and systolic function. This may indicate a role for pregnancy in the development of HFpEF, and suggests that multiparous women should be targeted for intensification of preventative measures for HFpEF.