Objective:To evaluate the safety of leadless pacemaker implantation in super-elderly patients.Methods:Eleven patients with average age of 90 (86, 92) years who underwent leadless pacemaker implantation in the Department of Cardiology, Peking University People′s Hospital from March 2021 to May 2022 were included. The clinical data and implantation information were collected. The complications (cardiac tamponade, myocardial infarction, cerebral infarction, pulmonary embolism, pacemaker reinfection, femoral vein hematoma) and death of patients were documented at 24 h, 3 d, and 1, 3, 6 months after pacemaker implantation.Results:There were 9 males and 2 females with the body mass index of 21(19, 23)kg/m 2. The underlying diseases were hypertension, diabetes, coronary heart disease, chronic kidney disease, chronic obstructive pulmonary disease, previous cerebral infarction and moderate to severe tricuspid regurgitation in 9, 9, 9, 6, 4, 4, 4 patients, respectively. The left ventricular ejection fraction was 49% (45%, 52%), the hemoglobin concentration was 118 (114, 122)g/L, 4 patients were taking anticoagulant drugs, and 6 patients were taking antiplatelet drugs. Eight patients were newly implanted with a leadless pacemaker, 2 patients were implanted after removal the old ones, and 1 case was implanted at the same time as removal. The implantation time was 45(40, 47) minutes, the X-ray exposure time was 14 (13, 15) minutes, the release time was 1 (1, 2), the threshold value was 0.50(0.38, 0.75)V/0.24 ms, the impedance was 730 (700, 770) Ω, and the perceived R-wave amplitude 8.2(6.7, 12.8) mV. During the follow-up period of 8 (6, 10) months, no patient had pacemaker dysfunction; and the threshold, R wave sensing, and impedance were stable and maintained within the normal range. No cardiac tamponade, myocardial infarction, cerebral infarction, pulmonary embolism, pacemaker reinfection or death occurred perioperatively and during the follow-up period; 1 patient had hematoma after femoral vein puncture, which improved after compression treatment. Conclusion:This single-center and small-sample study shows that leadless pacemaker implantation is safe for super-elderly patients.

BACKGROUNDCardiac resynchronization therapy (CRT) on patients with advanced and refractory heart failure has made remarkable progress. Clinically, notched QRS (nQRS) is commonly seen on electrocardiographs (ECGs) with bundle branch block morphology and on paced ECGs after implantation of a CRT device, which may reflect the heterogeneity of ventricular myocardial depolarization and electrical activity. The aim of this study was to determine whether patients with more nQRS myocardial segments on paced ECGs had a worse response to CRT than patients with fewer nQRS myocardial segments.

METHODSWe prospectively enrolled 56 patients of CRT with chronic heart failure from People's Hospital affiliated to Peking University from January 2007 to October 2013. Based on nQRS segments on ECGs before CRT, we allocated them to two groups: fewer nQRS (<2) myocardial segments (lateral, inferior, anterior segments) group (F-nQRS, G1, n = 23) and more nQRS (≥2) myocardial segments group (M-nQRS, G2, n = 33). Then according to nQRS segments on ECGs after CRT, we divided them into two groups similarly: fewer nQRS (<2) myocardial segments group (G3, n = 24) and more nQRS (≥2) myocardial segments group (G4, n = 32). This study was approved by the ethics committee of People's Hospital.

RESULTSAt 6 months in the baseline-ECG group, there was a greater absolute increase in left ventricular ejection fraction (LVEF) in G2 than in G1 ((11.5±8.9)% vs. (5.5±10.4)%, P = 0.023), with the incidence of nonresponse lower in G2 than in G1 (9.1% vs. 39.1%, P = 0.018). In the paced-ECG group, the absolute increase in LVEF was less in G4 than in G3 ((6.4±8.8)% vs. (12.5±10.4)%, P = 0.024) and the incidence of nonresponse was higher in G4 than in G3 (31.3% vs. 8.3%, P = 0.039). Multivariate analysis showed that fewer nQRS (<2) myocardial segments on paced ECGs (odds ratio 13.920) was a predictor of positive response to CRT.

CONCLUSIONnQRS ≥2 myocardial segments (lateral, inferior, anterior) on paced ECGs may predict a poor response to CRT.

Aged ; Cardiac Resynchronization Therapy ; Electrocardiography ; Female ; Heart Failure ; therapy ; Humans ; Male ; Middle Aged ; Predictive Value of Tests ; Prospective Studies