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Cryopreserved aortic allografts were durable for more than 15 years. Structural deterioration of aortic allografts was related to multiple factors. The age of the recipient and the donor, obesity and blood transfusion history of the recipient, and implantation technique were identified as the most important factors contributing to allograft failure.

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Despite their low density, beta(2)-adrenergic receptors are nearly as effective as beta(1)-adrenergic receptors of infant Fallot ventricle in enhancing contraction, relaxation, and phosphorylation of phospholamban and troponin I, consistent with selective coupling to G(s)-protein.

ALCAPA (anomalous left coronary artery from pulmonary artery) syndrome is a rare congenital abnormality that involves an anomalous insertion of the left coronary artery into the pulmonary artery. Ninety percent of patients present in the first year of life with signs and symptoms of heart failure or sudden cardiac death secondary to chronic myocardial ischemia. There have been an increasing number of reports of ALCAPA patients surviving to adulthood. There seems, however, to be a tendency to die suddenly in the third decade of life. Adult survivors are either asymptomatic or present with mitral regurgitation, cardiomyopathy, myocardial ischemia, or malignant arrhythmias. The management of the older patient presenting with symptoms resulting from ischemia and progressive left ventricular dysfunction remains a challenge. Treatment is largely based on guidelines for adult congenital heart disease management and an extrapolation of evidence from heart failure practice. Currently, surgical reimplantation of the anomalous coronary onto the aorta is the mainstay of treatment. The management of heart failure, sudden cardiac death, and ventricular arrhythmia present problems that are not addressed by reimplantation of the anomalous vessel alone. In this report, we present two cases with different modes of presentation and discuss treatment options.

Postoperative junctional ectopic tachycardia (JET) is a potential life-threatening tachycardia that mainly occurs after surgical correction of congenital heart defects. The arrhythmia itself or the related treatment has significant clinical impact on the postoperative course and intensive care stay. In general, JET is a self-limiting disorder that usually resolves within one week. However, JET occurs usually within the first 24 to 48 hours after corrective surgery, when systolic and diastolic function of the heart is impaired. Thus, the rapid heart rate leads to an acute further deterioration of cardiac output that requires adequate treatment. The diagnosis of JET is made by the typical ECG-appearance with narrow QRS-configuration at a rate of 170 to 260 bpm and AV-dissociation. A variety of different therapeutic strategies have been tested in postoperative and congenital/spontaneous JET. Treatment success is usually defined as a stable decrease in the ventricular rate below 140-150/min, the possibility of atrial pacing and thereby the improvement of cardiac output. Optimal success is the reinstitution of sinus rhythm. Many of the treatment strategies reported are based on specific institutional treatment protocols. These include conventional supportive treatment, specific medical antiarrhythmic therapy, specific forms of pacing and surface cooling. Today, the administration of high doses of amiodarone usually leads to adequate control of the rate and enables pacing. Surgical intervention or catheter ablation of the HIS-bundle is rarely necessary. This article reviews the literature about JET over the past years and offers a specific treatment protocol.

One hundred and twenty‐four patients underwent aortic valve replacement with a nonviable 4°C refrigerated aortic allograft valve. One hundred and eighty‐four patients underwent aortic valve replacement with a viable cryopreserved aortic allograft valve in a later era. The longest follow‐up was 16 years for the group with the nonviable valve and 11 years for the group with the viable valves. Within this time frame, reoperation was required in 23 patients with nonviable valves for leaflet perloration or rupture whereas no patients in the group with viable valves developed this complication (p < 0.0001). The prevalence of endocarditis and thromboembolism was very low in both groups. Viability of leaflet tissue is associated with an important improvement in durability over nonviable allograft valves. Consequently, long‐term follow‐up results of allograft valves might be best expressed in terms of viability. The current evidence suggests that the viable cells are donor in origin. The viable cryopreserved aortic allograft valve offers significant advantages over current nonviable allograft valves, mechanical valves, and bioprostheses.