Acute and long‐term outcomes of quadripolar IS‐4 versus bipolar IS‐1 left ventricular leads in cardiac resynchronization therapy: A retrospective registry study

Abstract

AbstractBackgroundThe implantation procedure of left ventricular (LV) leads and the management of cardiac resynchronization therapy (CRT) patients can be challenging. The IS‐4 standard for CRT offers additional pacing vectors compared to bipolar leads (IS‐1). IS‐4 leads improve procedural outcome and may also result in lower adverse events during follow‐up (FU) and improve clinical outcome in CRT patients. Further long‐term FU data comparing the two lead designs are necessary.MethodsIn this retrospective, single‐center study we included adult patients implanted with a CRT‐Defibrillator (CRT‐D) or CRT‐Pacemaker (CRT‐P) with a quadripolar (IS‐4 group) or bipolar (IS‐1 group) LV lead and with available ≥3 years clinical FU. The combined primary endpoint was a combination of predefined, lead‐related adverse events. Secondary endpoints were all single components of the primary endpoint.ResultsOverall, 133 patients (IS‐4 n = 66; IS‐1 n = 67) with a mean FU of 4.03 ± 1.93 years were included. Lead‐related adverse events were less frequent in patients with an IS‐4 lead than with an IS‐1 lead (n = 8, 12.1% vs. n = 23, 34.3%; p = .002). The secondary outcomes showed a lower rate of LV lead deactivation/explantation and LV lead dislodgement/dysfunction (4.5% vs. 22.4%; p = .003; 4.5% vs. 17.9%; p = .015, respectively) in the IS‐4 patient group. Less patients suffered from unresolved phrenic nerve stimulation with an IS‐4 lead (3.0% vs. 13.4%; p = .029). LV lead‐related re‐interventions were fewer in case of an IS‐4 lead (6.1% vs. 17.9%; p = .036).ConclusionIn this retrospective analysis, the IS‐4 LV lead is associated with lower lead‐related complication rates than the IS‐1 lead at long‐term FU.