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A F Corno

Publications and source records attributed to A F Corno.

25 records · Page 2Linked to original sources

Prevention of reperfusion injury in the neonatal heart with leukocyte-depleted blood.

Activated leukocytes release oxygen free radicals and cause microvascular occlusion. This experiment tests the hypothesis that reperfusion with leukocyte-depleted blood reduces injury after extended ischemic preservation. An in vitro model consisting of an isolated, working neonatal piglet heart and an adolescent support pig was used. Hearts were arrested with a cold crystalloid cardioplegic solution, excised, and stored in 4 degrees C saline for 12 hours. Two groups were compared. In group 1 piglets (n = 8), reperfused with whole blood, the maximum stroke work index was 0.91 +/- 0.29 x 10(3) erg/gm (mean +/- standard error of the mean). Group 2 piglets (n = 6), reperfused with blood depleted of leukocytes by a polyester filter, had a maximum stroke work index of 11.6 +/- 1.0 x 10(3) erg/gm. This difference was highly significant (p less than 0.0001). Group 1 exhibited severe injury with myofibrillar necrosis, mitochondrial disruption, nuclear chromatin clumping, and moderate interstitial edema. Group 2 had normal ultrastructure on electron microscopic examination. We conclude that reperfusion with leukocyte-depleted blood prevents reperfusion injury and results in excellent myocardial function after long-term heart preservation.

Animals↗

Long-term neonatal heart preservation.

UNLABELLED: Donor availability is a major limiting factor in neonatal heart transplantation. Prolonging donor heart preservation would facilitate distant heart procurement. Forty-two neonatal (1 to 5 days) piglet hearts in seven groups were arrested with cold cardioplegic solutions, stored for 12 hours at 4 degrees C in storage solutions, and reperfused with blood from an adult support pig. The cardioplegic solutions used were a crystalloid solution with potassium chloride 30 mEq/L and bicarbonate (Stanford), the Stanford cardioplegic solution with the addition of calcium (1.2 mmol/L), or an intracellular solution (Sacks) with added glucose. Storage solutions were normal saline, Sacks II, or Sacks II with glucose 20 gm/L. Reperfusion was done with normal blood or modified blood for 20 minutes with superoxide dismutase, catalase, aspartate, glutamate, citrate-phosphate-dextrose, potassium, tromethamine, and 50% dextrose followed by normal blood. Evaluation of stroke work index after 60 minutes of recovery (as percent of control) was performed using the isolated, blood perfused, working heart preparation in all groups: Group I (Stanford cardioplegia, saline storage, normal blood reperfusion) had a recovery of 11%; group II (Stanford + calcium, saline, normal blood) 8%; group III (Stanford + calcium, saline, modified blood, superoxide dismutase 35,000 U/L, catalase 35,000 U/L) 37%; group IV (Stanford + calcium, Sacks II, modified blood, superoxide dismutase 35,000 U/L, catalase 35,000 U/L), 47%; group V (Stanford + calcium, Sacks + glucose, modified blood, superoxide dismutase 35,000 U/L, catalase 105,000 U/L) 89%; group VI (Stanford + calcium, Sacks + glucose, modified blood, superoxide dismutase 150,000 U/L, catalase 150,000 U/L) 107%; group VII (Sacks + glucose, Sacks + glucose, modified blood, superoxide dismutase 35,000 U/L, catalase 105,000 U/L) 115%. CONCLUSIONS: The neonatal heart stored hypothermically for 12 hours tolerates normal blood reperfusion poorly. Modified blood reperfusion markedly improves the recovery. Complete functional recovery was achieved by the intracellular Sacks plus glucose storage solution and modified blood reperfusion with oxygen-derived free radical scavengers (high catalase). Extended preservation of the neonatal heart is feasible.

Animals↗

Palliative Mustard operation: an expanded horizon.

From March 1982 to December 1983, five patients with a mean age 7 years (4 months-16 years) underwent a palliative Mustard operation for complex cardiac anomalies. The diagnoses were: univentricular heart with pulmonary vascular obstructive disease (PVOD) (2 cases); criss-cross heart with intact atrial septum, ventricular septal defect (VSD), transposition of the great arteries (TGA) and moderate pulmonary stenosis; isolated atrioventricular discordance with VSD; TGA, diminutive right ventricle and multiple VSDs. Cardiac catheterization showed unfavourable direction of flow: the oxygen saturation in the aorta was lower than in pulmonary artery, with a mean difference of 13.5% (range 6% to 30%). In no case was anatomical or physiological repair considered advisable because of the unfavourable intracardiac anatomy or the presence of PVOD. In two patients the atrial rerouting was accompanied by pulmonary artery banding. There were no hospital or late deaths in a mean follow-up of 36 months (range 29 to 50 months). The mean post-operative arterial oxygen saturation was 95.4% (range 92% to 99%).

Adolescent↗

Use of in situ pericardium for surgical relief of pulmonary venous obstruction following Mustard's operation.

A technique is described for relief of pulmonary venous obstruction following the Mustard procedure. The functional left atrium is enlarged by using the pericardium in situ. This is expected to allow for growth of the pericardial patch and to avoid recurrent obstructions. This technique has also been used in reoperations for systemic venous obstruction after enlargement of the systemic baffle with a patch.

Heart Atria↗

Myocardial protection in the neonatal heart. A comparison of topical hypothermia and crystalloid and blood cardioplegic solutions.

UNLABELLED: Myocardial protection achieved during 2 hours of ischemic arrest was evaluated in 45 isolated, blood perfused, neonatal (1 to 5 days) piglet hearts. Comparisons were made among five methods of myocardial protection: Group I, topical cooling; Group II, hyperosmolar (450 mOsm) low-calcium (0.5 mmol/L) crystalloid cardioplegia; Group III, St. Thomas' Hospital cardioplegia; Group IV, cold blood cardioplegia with potassium (21 mmol/L), citrate-phosphate-dextrose (calcium level 0.6 mmol/L), and tromethamine; and Group V, cold blood cardioplegia with potassium alone (16 mmol/L) (calcium level 1.2 mmol/L). Hemodynamic recovery (percent of the preischemic stroke work) after 30 and 60 minutes of reperfusion was 82.9% and 86.7% in Group I, 35.7% (p less than 0.0001) and 43.7% (p less than 0.0001) in Group II, 76.1% and 77.7% in Group III, 67.4% (p less than 0.05) and 60.6% (p less than 0.05) in Group IV, and 110.7% and 100.6% in Group V. CONCLUSIONS: Topical cooling is an effective method of myocardial protection in the neonate. Cold blood cardioplegia with potassium alone and a normal calcium level provides optimal functional recovery. The improved protection obtained with both crystalloid and blood cardioplegia with normal calcium levels suggests an increased sensitivity of the neonatal heart to the calcium level of the cardioplegic solution.

Animals↗

The heterotopic right heart assist transplantation.

Heterotopic heart transplantation has been utilized experimentally and clinically to assist the recipient heart in maintaining either the systemic circulation alone or both the systemic and pulmonary circulations. We describe a model in which the heterotopic heart transplantation is utilized to supply the pulmonary circulation while the recipient heart acts as the systemic ventricle. This procedure might be used for selected patients with complex congenital heart disease. The method we have used in five dogs (16.5 to 23.5 kg) consists of preparation of the donor heart by excision after cardioplegic arrest, ligation of the venae cavae, anastomosis of the donor pulmonary artery (PA) to the donor left atrial appendage, and insertion of a left ventricular (LV) apical Dacron graft connected to a valved aortic allograft. Implantation in the recipient consists of anastomosis of the donor left atrium to the recipient right atrium, anastomosis of the LV apical conduit to the recipient main PA, and anastomosis of the donor aorta to the recipient ascending aorta to supply oxygenated blood to the donor coronary circulation. The recipient right ventricle (RV) in the experimental model is inactivated by inducing tricuspid regurgitation and by ligating the proximal PA. Early survival (3 hours) with stable hemodynamic measurements was obtained in all dogs, with the recipient RV excluded from the circulation and with the donor LV pumping the total systemic venous return to the PA. Pulmonary blood flow was maintained even when the ventricular pressure was raised to systemic levels by narrowing the conduit.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

Heart transplantation in a Jehovah's Witness.

Heart transplantation has been successfully performed without blood products in a 45-year-old Jehovah's Witness. Management of this patient is described. The medical, ethical, and religious issues involved in the decision to offer transplantation and to accept it are discussed.

Blood Transfusion, Autologous↗