Optimization of the atrioventricular delay during cardiac resynchronization therapy using a device for non-invasive measurement of cardiac index at rest and during exercise.

AIMS: It is not clear whether cardiac resynchronization therapy (CRT) should only be optimized at rest or whether it is necessary to perform CRT optimization during exercise. Our study aims to answer this question by using an inert gas rebreathing method (Innocor®). METHODS AND RESULTS: Twenty-seven patients with congestive heart failure and implanted CRT devices were included in the study. The aetiology of the heart failure was ischaemic in nine (33%) patients. Patients had low left ventricular ejection fraction (29 ± 8%) and enlarged LV end-diastolic diameters (63 ± 7 mm). Atrioventricular delay (AVD) was optimized at rest according to cardiac index (CI), measured by inert gas rebreathing (Innocor®). Thereafter, patients performed standardized, steady-state bicycle exercise at 30 W in sitting body position. Three AVDs were tested during exercise in a random sequence: optimized resting AVD (AVD(opt)) according to baseline measurement; AVD(opt) - 30 ms; and AVD(opt) + 30 ms. Cardiac index was measured in each AVD by inert gas rebreathing. Cardiac index increased significantly during exercise. However, neither AVD(opt) shortening nor prolongation during exercise had significant effect on CI (shortening of AVD(opt) - 30 ms was accompanied by a reduction of CI of 4.8%, prolongation of AVD(opt) + 30 ms was accompanied by a reduction of CI of 7.7%). CONCLUSION: Shortening or lengthening of the AVD during exercise has no impact on CI in CRT patients. On the basis of our results, we conclude that in CRT patients the AVD should be programmed, fixed even during exercise.

Interferon-α for Induction and Maintenance of Remission in Eosinophilic Granulomatosis with Polyangiitis: A Single-center Retrospective Observational Cohort Study.

OBJECTIVE: Eosinophilic granulomatosis with polyangiitis (EGPA) is characterized by frequent relapses following induction therapy. Interferon-α (IFN-α) can reverse the underlying Th2-driven immune response and has successfully induced remission in previous reports. We undertook this study to investigate its efficacy and safety in patients with EGPA. METHODS: We conducted a retrospective monocentric cohort study including 30 patients (16 women) with active EGPA under IFN-α treatment. Primary endpoints were remission induction, occurrence of relapses, prednisolone (PSL) dosage at time of remission, and adverse events. Remission was defined by a Birmingham Vasculitis Activity Score (BVAS) of 0. Pulmonary function tests were recorded at baseline and at time of remission. Health-related quality of life was analyzed by questionnaire at baseline and following 12 months of treatment. RESULTS: At baseline, the median BVAS was 6 (interquartile range 4-13.5) and remission or partial response was achieved in 25/30 patients. After initiation of IFN-α treatment, the median PSL dosages could be reduced from 17.5 mg/day at baseline to 5.5 mg/day at time of remission. Following remission, 17 relapses (5 major) in 16 patients were observed. Pulmonary function tests improved and the time of hospitalization decreased. Adverse events at initiation of treatment were common, but mostly transient. Severe adverse events occurred during treatment in 4 patients (autoimmune hepatitis, n = 1; drug-induced neuropathy, n = 3). CONCLUSION: IFN-α treatment results in high rate of remission and maintenance in EGPA with significant reduction in oral corticosteroids, although reversible adverse events may occur. IFN-α represents an alternative therapeutic option in cases of refractory to standard treatment.