Warnes, Carole A.

The management of women with mechanical heart valves during pregnancy remains difficult and controversial. There is no ideal anticoagulation regimen for this unique population, as there are inherent risks and benefits of each approach for both mother and fetus. There has been limited data available to guide the clinician in the optimal treatment strategy for an individual patient. The AHA/ACC Guidelines for the Management of Patients with Valvular Heart Disease created class recommendations for this population based upon current evidence, which is summarized in this review.

Background— Most patients with repaired tetralogy of Fallot require pulmonary valve replacement (PVR), but the evaluation for and management of ventricular arrhythmia remain unclear. This study is aimed at clarifying the optimal approach to this potentially life-threatening issue at the time of PVR. Methods and Results— A retrospective analysis was performed on 205 patients with repaired tetralogy of Fallot undergoing PVR at our institution between 1988 and 2010. Median age was 32.9 (range, 25.6) years. Previous ventricular tachycardia occurred in 16 patients (8%) and 37 (16%) had left ventricular dysfunction, defined as left ventricular ejection fraction <50%. Surgical right ventricular outflow tract cryoablation was performed in 22 patients (10.7%). The primary outcome was a combined event including ventricular tachycardia, out-of-hospital cardiac arrest, appropriate implantable cardioverter defibrillator therapy, and sudden cardiac death. Freedom from the combined event at 5, 10, and 15 years was 95%, 90%, and 79%, respectively. In the first year after PVR, 2 events occurred. Conversely, in the 22 patients who underwent surgical cryoablation, a single event occurred 7 years after PVR. A history of ventricular tachycardia and left ventricular dysfunction was associated with higher risk for the combined event (hazard ratio, 4.7; P =0.004 and hazard ratio, 0.8; P =0.02, respectively). Conclusions— Patients with repaired tetralogy of Fallot undergoing PVR with history of ventricular tachycardia or left ventricular dysfunction appear to be associated with a higher risk of arrhythmic events after operation. Events in the first year after PVR are rare, and in select high-risk patients, surgical cryoablation does not seem to increase arrhythmic events and may be protective.

SummaryObjectivesTo describe the experience of a single, tertiary care institution in the care of patients with Fontan physiology undergoing anesthesia for noncardiac surgery.BackgroundThe Fontan procedure was developed in 1971 to palliate patients with univentricular cardiac physiology leading to long‐term survival of these patients, who may now present as adults for noncardiac surgery.MethodsWe retrospectively reviewed the medical records of Fontan patients 16 years and older who underwent general anesthesia for noncardiac surgery at Mayo Clinic in Rochester, Minnesota. Preoperative data, perioperative course, intraoperative and postoperative hemodynamic, pulmonary, cardiovascular, and renal complications were described.ResultsThirty‐nine general anesthetics were administered to 31 patients for noncardiac surgery after Fontan palliation. Perioperative complications occurred in 12 of the 39 (31%) noncardiac surgeries, and there was one postoperative death that occurred on day 13 after ventral hernia repair. The two patients who had complications that did not resolve (long‐term dialysis and death) had ejection fractions well below the mean for the group (22% and 28%).ConclusionIt may be more appropriate for Fontan patients to undergo anesthesia for noncardiac surgery in a tertiary institution, particularly patients with an ejection fraction of <30%. Intraoperative arterial blood pressure monitoring and overnight admission are likely appropriate for most cases.

BackgroundSinus venosus atrial septal defect (SVD) is underdiagnosed with transthoracic echocardiography because of its posterior (far field) location. Transesophageal echocardiography (TEE) should be ideally suited to diagnose SVD, given the proximity of the transducer to the defect.Methods and ResultsA retrospective study was undertaken that used the medical history, echocardiographic findings, and surgical data of patients identified from computer records as having the diagnosis of SVD during the period in which TEE has been in use (1987 to 1995). Twenty-five patients (14 females and 11 males; median age, 45 years; range, 10 to 75 years) with SVD had TEE between 1987 and 1995. Prior transthoracic echocardiography clearly defined the SVD in 3 of these patients, and it was suspected in another 11 on the basis of color-flow imaging. Ten patients had unexplained dilatation of the right side of the heart, which prompted TEE examination. SVD was visualized with TEE in all 25 patients and ranged in size from 1 to 3 cm. Thirty-seven right-sided anomalous pulmonary venous connections were identified in 23 patients. No left-sided anomalous pulmonary venous connections were detected. Anatomic confirmation was obtained in all 23 surgical patients. No patient required preoperative cardiac catheterization for diagnosis.ConclusionsTEE is accurate for the diagnosis of SVD and should be undertaken in any patient with unexplained dilatation of the right side of the heart. The associated pulmonary venous abnormalities can be identified with TEE. Cardiac catheterization for diagnostic purposes should not be required before surgical correction.

Amiodarone therapy in adults with congenital heart disease (CHD) is associated with a significant risk of amiodarone-induced thyrotoxicosis (AIT). We developed a risk index to identify those patients being considered for amiodarone treatment who are at high risk for AIT. We reviewed the health records of adults with CHD and assessed the association between potential clinical predictors and AIT. Significant predictors were included in multivariate analyses. The parameter estimates from multivariate analysis were subsequently used to develop a risk index. 169 adults met eligibility criteria and 23 developed AIT. The final model included age, cyanotic heart disease and BMI. The risk index developed identified 3 categories of risk. Their AIT likelihood ratios were: 0.37 for low risk (95% CI 0.15–0.92); 1.12 for medium risk (95% CI 0.65–1.91); and 3.47 for high risk (95% CI 1.7–7.11). The AIT predicted risk in our population was 5% for the low risk group, 15% for the medium risk group and 47% for the high risk group. Conclusions . We derived the first model to quantify the risk for developing AIT among adults with CHD. Before using it clinically to help selecting among alternative antiarrhythmic options, it needs validation in an independent population.

Many patients with ventriculoarterial discordance have survived to adulthood. Those with complete transposition of the great arteries have often had an atrial switch procedure (Mustard or Senning operation) performed, which leaves the morphological right ventricle (RV) supporting the systemic circulation. RV failure and tricuspid regurgitation are common. Some patients may ultimately require cardiac transplantation. Sinus node dysfunction is increasingly common with longer follow-up, and some patients need pacemaker implantation. Atrial arrhythmias are frequent, and atrial flutter may be a marker for sudden death. Patients with an arterial switch procedure are also surviving to adulthood. Long-term problems include coronary stenoses, distortion of the pulmonary arteries, dilatation of the neoaortic root, and aortic regurgitation. Patients with congenitally corrected transposition have both atrioventricular and ventriculoarterial discordance and therefore also have a morphological RV and delicate tricuspid valve in the systemic circulation. Associated defects, such as abnormalities of the tricuspid valve, ventricular septal defect, and pulmonary stenosis, occur in the majority of patients. Heart block occurs with increasing age. Atrial arrhythmias occur frequently, and their occurrence should prompt a search for a hemodynamic problem. Progressive tricuspid regurgitation occurs with age and is associated with deterioration of RV function. Surgical treatment should be considered at the earliest sign of RV dilatation or dysfunction. All patients should be seen periodically in a center where expertise in the clinical evaluation, imaging, and hemodynamic assessment of adult congenital heart disease is available.