William A. Baker

Left ventricular performance improves late after aortic valve replacement in patients with aortic stenosis and reduced ejection fraction

EF in patients with aortic stenosis and reduced EF who underwent aortic valve replacement did not improve by 1 week postoperatively despite rectification of afterload mismatch. By 6 months, however, EF significantly improved without any further change in ventricular loading conditions. This implies that the benefit from aortic valve replacement (when measured by LV ejection performance) may not be evident until late postoperatively.

Effect of inadequate cardiac output reserve on exercise tolerance in patients with moderate mitral stenosis.

Twenty-nine patients with moderate mitral stenosis and 29 age-matched normal controls underwent symptom-limited upright bicycle exercise testing with simultaneous hemodynamic monitoring. Exercise tolerance in the mitral stenosis group was found to be limited by inadequate cardiac output reserve and not by resting mitral valve area or exercise pulmonary capillary wedge pressure.

Esophageal varices in association with unilateral pulmonary vein atresia

A 27-yr-old woman with recurrent episodes of hemoptysis (and hematemesis due to esophageal varices) was found to have unilateral pulmonary vein atresia. Reversed flow in the left pulmonary artery, a finding highly suggestive of this rare congenital anomaly, was demonstrated during cardiac catheterization. The definitive diagnosis was afforded by pulmonary wedge angiography, which not only demonstrated the atretic leftsided pulmonary veins, but also revealed a serpiginous system of systemic collateral veins to be the cause of her esophageal varices. Pneumonectomy of the nonfunctioning hypoplastic lung, the most successful approach to this disorder, may be complicated by severe bleeding of the numerous systemic arterial collateral vessels transected during surgical mobilization of the affected lung. Percutaneously delivered vascular occlusion coils were used in this case to occlude the large systemic to pulmonary artery collateral arteries immediately prior to pneumonectomy. Intra- and perioperative bleeding was minimal, and the patient has done well without further episodes of hemoptysis or hematemesis. Percutaneous occlusion of systemic to pulmonary collaterals may prove useful as a preoperative step for other congenital heart disease patients requiring lung or heart/lung transplantation.

Diagnosing coronary arterial stent thrombosis and arterial closure.

This single-center review of a consecutive series of patients requiring reexamination by angiography within 1 week of a coronary stent placement due to chest pain reveals that patients treated with a poststent anticoagulation regimen of warfarin and aspirin, and those with lower poststent deployment dilation pressures, have an increased risk of subacute stent thrombosis. Repeat cardiac catheterization within the first week after coronary artery stent implantation should be reserved for patients with significant electrocardiographic changes.