Determination of left atrium volume by fast anatomical mapping and intracardiac echocardiography. The contribution of respiratory gating.

BACKGROUND: The anatomical reconstruction of the left atrium (LA) and pulmonary veins with fast anatomical mapping (FAM) and intracardiac echocardiography (ICE) using the Carto 3 system (Biosense Webster, Inc) provides real-time guidance to catheter manipulation during ablation of atrial fibrillation (AF). The present study compared real-time LA volume reconstruction using FAM and ICE. In addition, the contribution of respiratory gating was assessed. METHODS: LA reconstruction was created using FAM and ICE in 60 consecutive patients (mean age 63 ± 9 years; 38 males) undergoing AF ablation. In the first 30 patients, FAM and ICE were performed without respiratory gating. In the last 30 patients, FAM and ICE were performed with respiratory gating. RESULTS: LA volumes determined by FAM were larger than those obtained with ICE in the absence of respiratory gating (n = 30; 129.5 ± 44 vs 110 ± 39.7 cm(3); p = 0.001). However, respiratory gating reduced LA volume determined with FAM by 17.7 ± 6.6% resulting in similar LA volumes to those obtained using ICE [n = 30; 100 ± 29.7 (61-154) vs 101.53 ± 40.1 (56-212) cm(3), p = 0.7, NS]. CONCLUSIONS: In the absence of respiratory gating, LA volumes determined by FAM are larger than those obtained with ICE. In contrast, with the addition of respiratory gating, both FAM and ICE provide similar real-time LA volumes.

Clinical efficacy of dofetilide for the treatment of atrial tachyarrhythmias in adults with congenital heart disease.

BACKGROUND: Atrial tachyarrhythmias (AT) including atrial fibrillation (AF), atrial flutter (AFL), and atrial tachycardia represent a clinical challenge in the adult with congenital heart disease (CHD). Dofetilide (D) is a rapidly activating delayed rectifier potassium channel (IKr) blocker effective in pharmacological conversion and maintenance of normal sinus rhythm in patients with AF and AFL. There is limited knowledge regarding the role of D in adults with CHD. METHODS: Safety and efficacy of D was evaluated in a consecutive group of thirteen adult patients (age 40 ± 11; six women) with CHD and refractory AT. RESULTS: Ten patients had persistent (four AFL, one AF, and five atrial tachycardia) and three paroxysmal (one AF and two atrial tachycardia) AT. All patients were symptomatic during tachycardia, 12 patients had previously failed 2 ± 1 antiarrhythmic drugs. Mean systemic ventricular ejection fraction was 55 ± 9%; baseline QRS complex duration was 129 ± 45 ms (>120 ms in six patients). Patients were followed on D for 33 ± 39 months (median 16). Among 10 patients with persistent AT, seven patients (70%) pharmacologically converted to sinus rhythm on D and three patients (30%) required direct current cardioversion. Two patients (15.4%) experienced complete arrhythmia suppression, and seven (53.8%) experienced significant clinical improvement with sporadic recurrences; average time to recurrence was 5.5 ± 3.5 months. One patient developed torsade de pointes during loading, and the drug was discontinued. D was discontinued in five (38.5%) other patients due to recurrence of AT (n = 4) and renal failure (n = 1). Corrected QT interval (QTc) increased from 452 ± 61 to 480 ± 49 ms (P = .04) and corrected JT interval (JTc) from 323 ± 39 to 341 ± 33 ms (P = .09). CONCLUSIONS: D should be considered a pharmacologic alternative when adult patients with CHD develop AT. D does not depress conduction, sinus node, or ventricular function but needs close monitoring for potential ventricular pro-arrhythmia.

Heart failure in pregnant women with cardiac disease: data from the ROPAC.

OBJECTIVE: Heart failure (HF) is one of the most important complications in pregnant women with heart disease, causing maternal and fetal mortality and morbidity. METHODS: This is an international observational registry of patients with structural heart disease during pregnancy. Sixty hospitals in 28 countries enrolled 1321 women between 2007 and 2011. Pregnant women with valvular heart disease, congenital heart disease, ischaemic heart disease, or cardiomyopathy could be included. Main outcome measures were onset and predictors of HF and maternal and fetal death. RESULTS: In total, 173 (13.1%) of the 1321 patients developed HF, making HF the most common major cardiovascular complication during pregnancy. Baseline parameters associated with HF were New York Heart Association class ≥ 3, signs of HF, WHO category ≥ 3, cardiomyopathy or pulmonary hypertension. HF occurred at a median time of 31 weeks gestation (IQR 23-40) with the highest incidence at the end of the second trimester (34%) or peripartum (31%). Maternal mortality was higher in patients with HF (4.8% in patients with HF and 0.5% in those without HF p<0.001). Pre-eclampsia was strongly related to HF (OR 7.1, 95% CI 3.9 to 13.2, p<0.001). Fetal death and the incidence of preterm birth were higher in women with HF compared to women without HF (4.6% vs 1.2%, p=0.001; and 30% vs 13%, p=0.001). CONCLUSIONS: HF was the most common complication during pregnancy, and occurred typically at the end of the second trimester, or after birth. It was most common in women with cardiomyopathy or pulmonary hypertension and was strongly associated with pre-eclampsia and an adverse maternal and perinatal outcome.