Abstract Immune thrombotic thrombocytopenic purpura (iTTP) is a chronically relapsing disorder caused by autoantibody-mediated deficiency of ADAMTS13. Rituximab is frequently administered to prevent relapses, but whether the durability of rituximab effect is maintained with subsequent treatment courses has not been studied. Using the United States Thrombotic Microangiopathy Consortium (USTMA) retrospective iTTP registry, we evaluated clinical relapse-free survival (RFS) with subsequent courses of rituximab treatment in multiply relapsing patients. Separately, we evaluated overall RFS (composite of time to clinical relapse, ADAMTS13 relapse, or preemptive rituximab) in a prospective iTTP cohort from the Johns Hopkins University and the University of Minnesota. In the USTMA registry, median clinical RFS was shorter after the second or subsequent rituximab-treated episode than the first (2.1 vs 6.0 years; P = .04). White patients’ clinical relapse risk after the second and subsequent rituximab courses was not significantly different compared with the first (hazard ratio [HR], 1.86; 95% confidence interval [CI], 0.22-15.80; P = .57), whereas for Black patients, clinical relapse risk was significantly higher after the second or subsequent courses (HR, 2.82; 95% CI, 1.52-5.24; P = .001). In the prospective cohort, overall RFS progressively shortened after each episode of rituximab treatment with the first episode having the longest RFS (2.8 years; interquartile range, 2.0-6.0) and this loss of response durability was most pronounced in Black patients. The durability of rituximab’s effect declines with subsequent treatments, which is more pronounced in Black patients, who may benefit from closer monitoring and alternative immunomodulatory approaches such as maintenance rituximab and consideration of other agents.
Role of Doppler echocardiography for assessing right ventricular cardiac output in patients with atrial septal defect
Background The purpose of this study was to compare the incidence of pregnancy‐related adverse outcomes ( PRAO ) between patients with versus without hemodynamically significant right ventricle outflow tract ( RVOT) . Methods and Results This was a retrospective cohort study of all pregnant patients with isolated RVOT lesions undergoing evaluation at the Mayo Clinic, 1990 to 2017. Hemodynamic significance was defined as ≥moderate pulmonary/conduit stenosis (≥3 m/s) and/or ≥moderate regurgitation. Patients with concomitant significant left heart disease were excluded. PRAO was defined as cardiovascular, obstetric, and/or neonatal complications occurring during the pregnancy through 6 weeks postpartum. A total of 224 pregnancies in 114 patients with RVOT lesions were identified; 38 pregnancies occurred in 24 patients with hemodynamically significant RVOT . Forty‐eight (21%) pregnancies ended in spontaneous abortion. Of the 173 completed pregnancies, median gestational age at delivery was 38 (35–40) weeks and median birth weight 2965 (2065–4122) g. Seven pregnancies (4%) were complicated by cardiovascular events, 14 (8%) by obstetric complications, with adverse neonatal outcomes occurring in 38 (22%). There were no maternal deaths. The incidence of spontaneous abortion and PRAO were similar in both the RVOT and hemodynamically significant RVOT groups. As an isolated condition, Tetralogy of Fallot–pulmonary atresia was associated with spontaneous abortion and neonatal complications. Conclusions The risk of cardiovascular complications was low in patients with isolated RVOT lesions, and hemodynamically significant RVOT lesions were not associated with either cardiovascular complications or PRAO . Further studies are required to explore the factors responsible for PRAO in patients with Tetralogy of Fallot–pulmonary atresia.
Cardiac implantable electronic devices in adults with tetralogy of Fallot
Background Tachyarrhythmias and bradyarrhythmias affect 20%–50% of adult patients with tetralogy of Fallot (TOF) and some of these patients will require cardiac implantable electronic devices (CIED) such as pacemaker and/or internal cardioverter defibrillator. Methods The Mayo Adult Congenital Heart Disease database was queried for patients with repaired TOF and history of CIED implantation, 1990–2017. The study objectives were: (1) determine the occurrence of device-related complications defined as lead failure, lead recall, device infection and lead thrombus; and (2) determine the occurrence and risk factors for defibrillator shock. Results There were 99 patients (age 46±14 years and 66 (66%) men) with CIED, and the CIEDs were 41 (41%) pacemakers and 73 (73%) defibrillators. Indication for defibrillator implantation was for primary prevention in 28 (38%) and secondary prevention in 45 (62%). Device-related complications occurred in 20 (20%) patients (lead failure 17, lead recall 4, device infection 12 and thrombus 3). Twenty-five per cent of all device infections occurred within 30 days from the time of device generator change. Annualised rates of appropriate and inappropriate shocks were 5.7% and 6.2%, respectively. The use of class III antiarrhythmic drug was protective against defibrillator shock. Conclusion The current study provides useful outcome data to aid patient counselling and clinical decision-making. Further studies are required to explore ways to decrease the risk of postprocedural infection after device generator change, and to determine which patients will benefit from empirical antiarrhythmic therapy as a strategy to decrease incidence of inappropriate defibrillator shock.