Noninvasive screening tools may miss heart failure amongst patients with atrial fibrillation and should be used with caution, Australian research has found.
The study evaluated both existing diagnostic scoring systems: HFA-PEFF (Heart Failure Association Pre-test assessment, Echocardiography and natriuretic peptide, Functional testing, Final aetiology) and the H2FPEF tool, finding issues with either sensitivity or specificity in each.
As a result, invasive assessment should remain the gold-standard method to diagnose HFpEF in patients with AF, despite the logistical challenges involved, the investigators say.
The data were based on 120 consecutive patients with symptomatic AF and preserved ejection fraction who were scheduled for AF ablation at Royal Adelaide Hospital, all of whom received risk scores using the two tools before undergoing invasive HFpEF diagnosis.
Performed at the ablation procedure, this involved using mean left atrial pressure at rest and following infusion of 500 mL fluid, which produced positive diagnoses for 88 (73%) participants.
By contrast, only 38 participants were rated as having a high probability of HFpEF using an HFA-PEFF score and only 72 under the H2FPEF assessment, demonstrating that these tools had “only moderate accuracy”, the researchers said.
When compared with the gold-standard diagnosis, a high HFA-PEFF (≥5 points) score could diagnose HFpEF with a sensitivity of 40% and a specificity of 91%, they reported in JACC: Heart Failure (link here)
On the other hand, a high H2FPEF score (≥6 points) could diagnose HFpEF with a sensitivity of 69% and specificity of 66%. Overall diagnostic accuracy was similar using both tools (AUC: 0.663 vs 0.707, respectively; P = 0.636).
“However, high probability of HFpEF according to both scoring systems was associated with important prognostic characteristics including elevated LA pressures and reduced LA function,” the authors wrote.
“Taken together, these data highlight the fact that invasive haemodynamic diagnosis of HFpEF remains the optimum method to diagnose HFpEF in patients with AF and that noninvasive scoring tools should be used with caution in this cohort of patients.”
Interestingly, the HFA-PEFF system demonstrated good specificity but poor sensitivity, frequently omitting younger male patients with obesity phenotype HFpEF.
The H2FPEF displayed better sensitivity but worse specificity and commonly omitted patients with normal haemodynamics at rest but abnormal haemodynamics with saline infusion (early HFpEF).
The upshot was that invasive testing should be used where possible, despite the difficulties involved, particularly when treating patients with limited access to major centres, said senior co-author Professor Prash Sanders of the University of Adelaide Centre for Heart Rhythm Disorders and Royal Adelaide Hospital.
“While the less invasive methods of testing were able to diagnose heart failure in AF patients with moderate accuracy, invasive testing is still needed to confirm results and remains the best diagnostic tool,” he said.
“Based on this, I would recommend these scoring systems be used with caution in AF patients.”