Efficacy and safety of ventricular tachycardia ablation with mechanical circulatory support compared with substrate-based ablation techniques.

AIMS: Catheter ablation of ventricular tachycardia (VT) can be limited by haemodynamic instability. In these cases, substrate-based ablation is typically performed. An alternative is to perform activation and entrainment mapping during VT supported by a percutaneous left ventricular assist device (pVAD). We sought to compare the complication and success rates of pVAD-assisted VT ablation with scar-based techniques. METHODS AND RESULTS: Thirteen consecutive patients with haemodynamically unstable VT underwent pVAD-assisted ablation (pVAD group) and were retrospectively compared with 18-matched patients undergoing a substrate-based VT ablation (non-pVAD group). There was no significant difference in age or ejection fraction between the groups although pVAD patients tended to have more shocks in the preceding months. Procedure times were longer for the pVAD group. The number of monomorphic VTs induced was greater in the pVAD group (3.2 vs. 1.6, P= 0.04); however, after ablation, there was no difference in inducibility between the pVAD and non-pVAD group (10 of 13 vs. 12 of 18; 77 vs. 67%, P = 0.69). There was no difference in acute complications including stroke or death. At 9 ± 3 months, 1-year freedom from implantable cardioverter-defibrillator (ICD) shocks/therapies for sustained VT were similar (P= 0.96). In multivariable analysis, the absence of atrial fibrillation (hazard ratio=0.15, P= 0.04) was associated with a lower incidence of ICD shocks. CONCLUSIONS: In high-risk patients, pVAD-assisted VT ablation guided by activation and entrainment mapping is a feasible alternative to substrate mapping and allows outcomes comparable to substrate mapping.

Real-world safety and efficacy of glycoprotein IIb/IIIa inhibitors during percutaneous coronary intervention.

BACKGROUND: Large randomized clinical trials have demonstrated differences in the efficacy and safety of glycoprotein (GP) IIb/IIIa inhibitors, but little has been published regarding comparisons of these agents in a "real-world" setting. PURPOSE: This study evaluated the safety and efficacy of GP IIb/IIIa inhibitors in a large population of patients who underwent percutaneous coronary intervention (PCI) during a 5-year period. METHODS: Patients undergoing PCI from 2000 through 2004 were eligible for inclusion if they received any single GP IIb/IIIa inhibitor. Patients with significant comorbidities were included. Patients were excluded if they received more than one GP IIb/IIIa inhibitor or underwent catheterization without PCI. Target activated clotting time was 200-250 seconds. RESULTS: Of 5,055 patients undergoing PCI, 4,321 (85%) received a single GP IIb/IIIa inhibitor (abciximab, 1,178; eptifibatide, 1,698; tirofiban, 1,445). Major bleeding complications were rare, ranging from 1.9-3.1%, and transfusion rates were low, ranging from 0.8-2.1%, with no significant differences among the agents evaluated. No significant differences in 1-year mortality, myocardial infarction, urgent target vessel revascularization or composite endpoint rates were identified among the therapeutic agents. CONCLUSIONS: In this large study of PCI patients, GP IIb/IIIa inhibition was associated with a low incidence of major bleeding complications and requirement of transfusion. With appropriate management, GP IIb/IIIa inhibitor use can benefit patients undergoing PCI, with minimal risk of bleeding complications.

Left ventricular assist device malfunction: a systematic approach to diagnosis.

OBJECTIVES: A protocol was designed to diagnose the common malfunctions of a left ventricular assist device (LVAD). BACKGROUND: Mechanical circulatory support, primarily with an LVAD, is increasingly used for treatment of advanced heart failure (HF). Left ventricular assist device dysfunction is a recognized complication; but heretofore, a systematic method to accurately diagnose LVAD dysfunction has not been thoroughly described. METHODS: We developed a catheter-based protocol designed to characterize a normally functioning LVAD and diagnose multiple types of dysfunction. A total of 15 studies of 10 patients supported with an LVAD were reviewed. All patients had been evaluated due to concerns regarding LVAD dysfunction. RESULTS: Of 15 examinations performed, 11 documented severe LVAD inflow valve regurgitation. One of these cases proved to have coexistent severe mitral valve regurgitation. One case was diagnosed with distortion of the LVAD outflow graft. One case of suspected embolization from the pumping chamber excluded the outflow graft as the source of emboli. One study had aortic insufficiency. CONCLUSIONS: As LVAD use for treatment of end-stage HF becomes widespread and durations of support are extended, dysfunction will be increasingly prevalent. This catheter-based protocol provided a practical method to diagnose multiple causes of LVAD dysfunction.