Long-term cardiovascular outcomes after pregnancy in women with heart disease

BACKGROUND: Women with heart disease are at risk for pregnancy complications, but their long-term cardiovascular outcomes after pregnancy are not known. METHODS AND RESULTS: We examined long-term cardiovascular outcomes after pregnancy in 1014 consecutive women with heart disease and a matched group of 2028 women without heart disease. The primary outcome was a composite of mortality, heart failure, atrial fibrillation, stroke, myocardial infarction, or arrhythmia. Secondary outcomes included cardiac procedures and new hypertension or diabetes mellitus. We compared the rates of these outcomes between women with and without heart disease and adjusted for maternal and pregnancy characteristics. We also determined if pregnancy risk prediction tools (CARPREG [Canadian Cardiac Disease in Pregnancy] and World Health Organization) could stratify long-term risks. At 20-year follow-up, a primary outcome occurred in 33.1% of women with heart disease, compared with 2.1% of women without heart disease. Thirty-one percent of women with heart disease required a cardiac procedure. The primary outcome (adjusted hazard ratio, 19.6; 95% CI, 13.8–29.0; P\u3c0.0001) and new hypertension or diabetes mellitus (adjusted hazard ratio, 1.6; 95% CI, 1.4–2.0; P\u3c0.0001) were more frequent in women with heart disease compared with those without. Pregnancy risk prediction tools further stratified the late cardiovascular risks in women with heart disease, a primary outcome occurring in up to 54% of women in the highest pregnancy risk category. CONCLUSIONS: Following pregnancy, women with heart disease are at high risk for adverse long-term cardiovascular outcomes. Current pregnancy risk prediction tools can identify women at highest risk for long-term cardiovascular events

A low-wear onload tap changer diverter switch for frequent voltage control on distribution networks

This paper presents a fast mechanical diverter switch design suitable for new “arcless” hybrid onload tap-changing systems. In such systems, arcing at contact separation and contact closure is almost completely eliminated by the inclusion of alternate current paths incorporating semiconductor devices. This allows the use of compact, air-insulated mechanical contacts that do not need to withstand significant arc erosion or provide arc quenching. As a result, the moving mass and the drive system for the switch may be dramatically reduced in size, leading to low inertia of the moving parts and resulting in very rapid operation times. An integrated, high-torque, low-mass permanent-magnet actuator is presented that provides detent (unpowered) contact force coupled with a cantilever spring contact system sized for an 11-kV 2-MVA onload tap changer. The design delivers operation times of under 20 ms and is capable of sustaining more than $10^{6}$ operations. The complete design is experimentally verified under representative electrical conditions, and contact wear levels comparable to pure mechanical (zero current) operation are demonstrated

Ventricular arrhythmias and sudden death in adults after a Mustard operation for transposition of the great arteries

Aims To examine the prevalence of sustained ventricular tachycardia (VT) and sudden death (SD) in adults with atrial repair of transposition of the great arteries (TGA) and to determine associated risk factors. Methods and results In a single-centre review, we studied the outcome of 149 adults (mean age 28 ± 7 years) who had undergone a Mustard operation for TGA. During a mean follow-up of 9 ± 6 years, sustained VT and/or SD occurred in 9% (13/149) of the cohort. Sustained VT/SD was more likely to occur in patients with associated anatomic lesions [hazard ratio (HR) 4.9, 95% CI 1.5-16.0], with NYHA class ≥III (HR 9.8, 95% CI 3.0-31.6) and with an impaired subaortic right ventricular (RV) ejection fraction (EF) (HR 2.2, 95% CI 1.2-4.0 per 10% decrease in EF). There was an inverse correlation between the RV-EF and both age and QRS duration. Patients with a QRS duration ≥140 ms were at highest risk of sustained VT/SD (HR 13.6, 95% CI 2.9-63.4). Atrial tachyarrhythmia was detected in 66 (44%) patients, but was not a statistically significant predictor of sustained VT/SD in our adult population (HR 2.7, 95% CI 0.6-13.0). Conclusion Sustained VT/SD in adults after a Mustard operation for TGA are more common than previously described. Age, systemic ventricular function, and QRS duration are interrelated and are associated with VT/SD. A QRS duration ≥140 ms helps to identify the high risk patien

Maternal cardiac output and fetal doppler predict adverse neonatal outcomes in pregnant women with heart disease

Background-The mechanistic basis of the proposed relationship between maternal cardiac output and neonatal complications in pregnant women with heart disease has not been well elucidated. Methods and Results-Pregnant women with cardiac disease and healthy pregnant women (controls) were prospectively followed with maternal echocardiography and obstetrical ultrasound scans at baseline, third trimester, and postpartum. Fetal/neonatal complications (death, small-for-gestational-age or low birthweight, prematurity, respiratory distress syndrome, or intraventricular hemorrhage) comprised the primary study outcome. One hundred and twenty-seven women with cardiac disease and 45 healthy controls were enrolled. Neonatal events occurred in 28 pregnancies and were more frequent in the heart disease group as compared with controls (n=26/127 or 21% versus n=2/45 or 4%; P=0.01). Multiple complications in an infant were counted as a single outcome event. Neonatal complications in the heart disease group were small-for-gestational-age/low birthweight (n=18), prematurity (n=14), and intraventricular hemorrhage/respiratory distress syndrome (n=5). Preexisting obstetric risk factors (P=0.003), maternal cardiac output decline from baseline to third trimester (P=0.017), and third trimester umbilical artery Doppler abnormalities (P \u3c 0.001) independently predicted neonatal complications and were incorporated into a novel risk index in which 0, 1, and \u3e 1 predictor corresponded to expected complication rates of 5%, 30%, and 76%, respectively. Conclusions-Decline in maternal cardiac output during pregnancy and abnormal umbilical artery Doppler flows independently predict neonatal complications. These findings will enhance the identification of higher risk pregnancies that would benefit from close antenatal surveillance

B-Type Natriuretic Peptide in Pregnant Women With Heart Disease

ObjectivesThe objectives of this study were to examine: 1) B-type natriuretic peptide (BNP) response to pregnancy in women with heart disease; and 2) the relationship between BNP levels and adverse maternal cardiac events during pregnancy.BackgroundPregnancy imposes a hemodynamic stress on the heart. BNP might be a useful biomarker to assess the ability of the heart to adapt to the hemodynamic load of pregnancy.MethodsThis was a prospective study of women with structural heart disease seen at our center. Serial clinical data and plasma BNP measurements were obtained during the first trimester, third trimester, and after delivery (>6 weeks).ResultsSeventy-eight pregnant women were studied; 66 women with heart disease (age 31 ± 5 years), and 12 healthy women (age 33 ± 5 years). During pregnancy, the median peak BNP level was higher in women with heart disease compared with control subjects (median 79, interquartile range 51 to 152 pg/ml vs. median 35, interquartile range 21 to 43 pg/ml, p < 0.001). In women with heart disease, those with subaortic ventricular dysfunction had higher BNP levels (p = 0.03). A BNP >100 pg/ml was measured in all women with events during pregnancy (n = 8). Sixteen women had increased BNP levels during pregnancy but did not have clinical events. None of the women with BNP ≤100 pg/ml had events. BNP ≤100 pg/ml had a negative predictive value of 100% for identifying events during pregnancy.ConclusionsMany pregnant women with heart disease have increased BNP levels during pregnancy. Incorporating serial BNP levels in into clinical practice can be helpful, specifically in adjudicating suspected adverse cardiac events during pregnancy