The unrecognized burden of HFpEF in pacemaker patients: results from a systematic heart failure program

Abstract Introduction Pacemaker patients have a high risk of developing HFpEF due to age, long-term cardiac changes secondary to artificial pacing, and associated comorbidities. Despite this risk, HFpEF remains underdiagnosed and poorly characterized in this population. Purpose Perform systematic screening for heart failure with preserved ejection fraction (HFpEF) in pacemaker patients to assess prevalence and characterize this population. Methods We conducted a large cross-sectional study to screen for heart failure in all patients with a right ventricular apical pacemaker implanted between January 2008 and December 2022. Each patient underwent a complete echocardiographic assessment, exercise echocardiography, NT-proBNP measurement, clinical examination, and pacemaker interrogation. We used the latest definition from the 2023 ESC guidelines to diagnose HF. Exclusion criteria were known EF <50%, moderate to severe or severe valvular disease, dependency in daily activities, stage 5 chronic kidney disease, and inability to attend the screening program. Results A total of 342 pacemaker patients (median age 78 ± 9 years, 60.1% male) were screened, with 45.6% having HF. Of these, 35.7% had HFpEF, 6.1% HFmrEF, and 3.8% undiagnosed HFrEF. HFpEF patients were older (81 vs. 75 years, p<0.001) and more often female (48% vs. 37%, p=0.04). They had a higher prevalence of left ventricular hypertrophy (75% vs. 52%, p=0.006), greater relative wall thickness (0.44 ± 0.09 vs. 0.40 ± 0.10, p=0.022), and larger indexed left atrial volume (87 ± 36 ml vs. 63 ± 21 ml, p<0.001). TAPSE was significantly reduced (21.9 mm vs. 23.1 mm, p=0.007) in this group, as were LV GLS (13.9% vs. 15.9%, p<0.001) and left atrial reservoir strain (18% vs. 28%, p<0.001). HFpEF patients had broader QRS (158ms vs. 146ms, p=0.001), QTc (453ms vs. 443ms, p<0.001), more prevalent bundle branch block (82% vs. 71%, p=0.03), and higher ventricular pacing rates (73% vs. 57%, p=0.004). They had higher rates of permanent (23% vs. 6.5%, p<0.001) and paroxysmal AF (34% vs. 26%, p<0.001). Additionally, HFpEF patients had lower hemoglobin (13.23 ± 1.67 vs. 13.80 ± 1.59, p=0.006), hematocrit (39.8 ± 4.5 vs. 41.4 ± 4.4, p=0.008), and albumin (4.45 ± 0.30 vs. 4.54 ± 0.29, p=0.037), with higher Troponin T (24 ± 16 vs. 16 ± 10, p<0.001), lower creatinine (1.18 ± 0.73 vs. 1.73 ± 10.00, p=0.013), reduced GFR (63 ± 22 vs. 74 ± 20, p<0.001), and decreased ferritin (183 ± 194 vs. 247 ± 265, p=0.022) and serum iron (72 ± 37 vs. 81 ± 28, p<0.001). Conclusion Our study revealed a high prevalence of HFpEF among pacemaker patients based on the latest ESC HF definitions, along with associated functional, analytical, and conduction abnormalities. These findings highlight this population's urgent need for HF screening programs, especially with new disease-modifying therapies now available for HFpEF.