Treatment of Fetal Supraventricular Tachycardia.

OPINION STATEMENT: Fetal arrhythmia is a common reason for referral to fetal cardiology. Fetal supraventricular tachycardia can be subdivided into several groups with the most common being re-entrant supraventricular tachycardia and atrial flutter. Fetal tachycardia can lead to hydrops fetalis, which increases the risk of fetal demise, perinatal morbidities, and premature delivery. The diagnosis of fetal tachycardia can be a challenge as a traditional electrocardiogram cannot be completed on a fetus, and other methods must be used by fetal echocardiogram. Several retrospective studies have been completed to determine the best treatment; however, there continues to be no consensus on the best option. Digoxin, flecainide, and sotalol are commonly used and have favorable results depending on gestational age, fetal well-being, and presence of hydrops. Treatment in a timely manner can convert supraventricular tachycardia to a normal fetal heart rate, and hydrops can resolve with delivery at term if the proper medications are used.

Longitudinal Strain and Strain Rate Abnormalities Precede Invasive Diagnosis of Transplant Coronary Artery Vasculopathy in Pediatric Cardiac Transplant Patients.

Transplant coronary artery vasculopathy (TCAV) is the primary cause of late graft loss in pediatric heart transplant recipients. TCAV is diagnosed using angiography or intravascular ultrasound; however, noninvasive methods remain elusive. We sought to define patterns of myocardial mechanics in patients with TCAV and to determine whether this can detect TCAV before invasive methods. In this retrospective study, we queried our heart transplant database to identify all recipients with TCAV since 2006 (n = 41). Echoes were reviewed from the last normal catheterization and at TCAV diagnosis, and from time-matched transplant controls (n = 33) without TCAV. Peak global circumferential and longitudinal strain and systolic and diastolic strain rate (SSR and DSR) of the left ventricle were derived using velocity vector imaging. T tests were used to compare both groups longitudinally and between groups at both time points. Longitudinal strain, SSR, and DSR were diminished in the TCAV group compared to the transplant control group at both time points. No differences were found across time points in either group. Retrospective modeling using a longitudinal strain cutoff of 15 % on echoes 2 years prior to TCAV diagnosis predicted development or exclusion of TCAV with sensitivity of 53 %, specificity of 89 % with an area under the curve of 0.8. Decreases in longitudinal strain measurements demonstrate that alterations in myocardial mechanics occur in patients with TCAV at least 2 years prior to invasive diagnosis. These early changes may be due to microvascular disease. This modality could aid in earlier treatment and intervention for this challenging problem .