RESUMEN
BACKGROUND: Lead-associated complications and technical issues in patients with cardiac implantable electronic devices are common but underreported in the literature. METHODS: All patients undergoing implantation of the Osypka QT-5® ventricular lead at the University Clinic St. Pölten between 1 January 2006 and 31 December 2012 were retrospectively analyzed (n = 211). Clinical data including pacemaker follow-up examinations and the need for lead revisions were assessed. Kaplan-Meier analysis to estimate the rate of lead dysfunction during long-term follow-up was conducted. RESULTS: Patients were followed for a median of 5.2 years (interquartile range (IQR) 2.0-8.7). R-wave sensing properties at implantation, compared to last follow-up, remained basically unchanged: 9.9 mV (IQR 6.8-13.4) and 9.6 mV (IQR 5.6-12.0), respectively). Ventricular pacing threshold significantly increased between implantation (0.5 V at 0.4 ms; IQR 0.5-0.8) and the first follow-up visit (1.0 V at 0.4 ms; IQR 0.8-1.3; p < 0.001) and this increase persisted throughout to the last check-up (0.9 V at 0.4 ms; IQR 0.8-1.2). Impedance significantly declined from 1142 Ω (IQR 955-1285) at implantation to 814 Ω (IQR 701-949; p < 0.001) at the first check-up, followed by a further decrease to 450 Ω (IQR 289-652; p < 0.001) at the last check-up. Overall, the Osypka QT-5® ventricular lead was replaced in 36 patients (17.1%). CONCLUSIONS: This report shows an unexpected high rate of technical issues of the Osypka QT-5® ventricular lead during long-term follow-up.
RESUMEN
OBJECTIVES: To evaluate the long-term performance of the SonRtip atrial lead. BACKGROUND: To optimize atrioventricular and interventricular timing and thereby potentially improving cardiac resynchronization therapy (CRT) responder rates, a lead integrated technology and a cardioverter/defibrillator-based algorithm measuring peak endocardial acceleration have been introduced. Long-term performance of the atrial lead (SonRtip PS55D, Sorin/MicroPort CRM, Italy) embedded with such a sensor has not been reported so far. METHODS: Between 2012 and 2018, 143 patients underwent implantation of the SonRtip atrial lead in four Austrian medical centers. Conventional bipolar atrial leads implanted during the same period in 526 patients receiving CRT were used as control cohort. RESULTS: Among 669 patients included in the study, 10 (1.5%) showed increased atrial pacing thresholds and/or decreased atrial sensing amplitudes and/or sudden increase in atrial lead impedance (above 3000 Ω) after an uneventful early postoperative period. Seven (70%) of the malfunctioning leads were SonRtip leads (p <0.001). Lead replacement was needed in 4.2% of SonRtip leads (six out of 143) and in 0.38% of all other conventional atrial leads (two out of 526) (p <0.001). Because of unaltered atrial sensing properties, a wait and see strategy was chosen in two patients-one of them with a SonRtip lead. The implanted atrial lead in the latter person experienced a sudden increase in pacing threshold (4V/0.35ms). CONCLUSIONS: While short-term safety and stable technical performance of the SonRtip atrial lead could be confirmed, our study found an unexpectedly high malfunction rate over a longer follow-up period.