Coronary artery occlusion after arterial switch operation in an asymptomatic 15-year-old boy.

A 15-year-old boy with transposition of the great arteries (TGA) and neonatal arterial switch operation (ASO) presented with complete occlusion of the left main coronary artery (LMCA). Intra-operatively, an intramural left coronary artery was identified. Therefore, since age 7 years he had a series of screening exercise stress tests. At 13 years old, he had 3 to 4 mm ST segment depression in the infero-lateral leads without symptoms. This progressed to 4.2 mm inferior ST segment depression at 15 years old with normal stress echocardiogram. Sestamibi myocardial perfusion scan and cardiac magnetic resonance imaging was inconclusive. Therefore, a coronary angiogram was obtained which showed complete occlusion of the LMCA with ample collateralization from the right coronary artery system. This was later confirmed on a computed tomogram (CT) angiogram, obtained in preparation of coronary artery bypass grafting. The case illustrates the difficulty of detecting coronary artery stenosis and occlusion in young patients with rich collateralization. Coronary CT angiogram and conventional angiography were the best imaging modalities to detect coronary anomalies in this adolescent with surgically corrected TGA. Screening CT angiography may be warranted for TGA patients, particularly for those with known coronary anomalies.

Transcarotid balloon valvuloplasty in neonates and small infants with critical aortic valve stenosis utilizing continuous transesophageal echocardiographic guidance: A 22 year single center experience from the cath lab to the bedside.

OBJECTIVE: Utilization of continuous transesophageal echocardiographic guidance (cTEE) during transcarotid balloon valvuloplasty (TCBV) in neonates and small infants with critical aortic valve stenosis (AS) allows for continuous hemodynamic assessment and improved outcomes. BACKGROUND: Preferred method of intervention for critical AS remains controversial due to conflicting results. METHODS: Since 1992, 30 neonates and small infants with critical AS and adequate left ventricular (LV) volumes underwent TCBV with cTEE. Critical AS was defined as ductal dependent systemic circulation, LV systolic dysfunction, or an echo gradient≥100 mm Hg with evidence of hypoperfusion. RESULTS: The median age at intervention was 4 days (range 1-54 days). Nineteen (63%) patients required PGE1 and 25 (85%) had LV dysfunction. All procedures were performed with cTEE guidance. The initial 15 patients were performed in the cath lab whereas the subsequent 15 patients were performed at the bedside without fluoroscopy. The peak systolic gradient decreased from 70 to 24 mm Hg (P<0.001). Four (13%) early deaths were secondary to associated cardiac anomalies although one patient developed severe aortic valve insufficiency (AI) immediately post intervention. At discharge, two patients (8%) had ≥moderate AI. At a mean follow-up of 9 years (range: 2.2-20 years), there were 15 additional aortic valve interventions. Freedom from aortic valve reintervention at 10 years was 55% and actuarial survival rate at 10 and 15 years was 82%. CONCLUSION: Bedsides TCBV with cTEE guidance is effective palliation for neonates and small infants with critical AS and allows for continuous hemodynamic assessment without the use of ionizing radiation. Our early and late results appear comparable to surgical valvotomy.

Quantitation of fetal heart function with tissue Doppler velocity imaging-reference values for color tissue Doppler velocities and comparison with pulsed wave tissue Doppler velocities.

Quantitative assessment of fetal heart function has been difficult. Increasingly, tissue Doppler imaging (TDI) is used to measure fetal cardiac function noninvasively. There are two principal techniques, spectral pulsed wave (PW) TDI and color TDI (CTDI). Published reference values for fetal myocardial velocities are based on spectral PW TDI only. However, previous phantom, adult, and animal studies have shown that PW TDI velocities are systematically higher than CTDI velocities. There are no fetal studies so far. We hypothesized that myocardial velocities derived by PW TDI and CTDI are significantly different in the fetus. This prospective observational study included 91 fetuses (gestational age 28.6 ± 6.6 weeks; range 19-40 weeks) seen for routine prenatal ultrasound. From apical 4-chamber views, tricuspid ring (right ventricle), lateral and septal mitral ring were sampled by PW TDI and CTDI. Bland-Altman analysis was used for comparisons. PW and CTDI S' velocities correlated strongly in all three cardiac segments (r = 0.6 to 0.9; P < 0.01). There was a systematic bias toward higher velocities with PW TDI versus CTDI (bias 0.96 cm/s; 95% CI 1.08-0.85 cm/s). However, the strength of the correlation and bias varied depending on the region of the fetal heart sampled. PW TDI and CTDI velocity measurements are feasible in the fetus and correlate well. However, PW TDI velocities are higher than CTDI velocities with significant regional variation. This precludes a mathematical conversion of PW to CTDI in vivo. As PW TDI and color TDI vary, different reference values for fetal CTDI velocities were generated.

Occult coronary ostial obstruction late after arterial switch operation.

Occult coronary artery obstruction can be a late source of morbidity and mortality following the arterial switch operation for transposition of the great arteries. We describe a case of undiagnosed left coronary ostial obstruction in a teenager which may have contributed to perioperative ventricular dysfunction and subsequent mortality following a reoperation many years after arterial switch.