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D Shimon

Publications and source records attributed to D Shimon.

13 recordsLinked to original sources
PubMed1996

Normothermic continuous blood cardioplegia improves electrophysiologic recovery after open heart surgery.

BACKGROUND: Myocardial protection during open heart surgery is based on administration of oxygenated blood cardioplegia, the preferred temperature of which is still under debate. The current randomized study was designed to prospectively evaluate the quality of myocardial protection and the functional recovery of the heart with either normothermic (group N) or hypothermic (group H) oxygenated blood cardioplegia. METHODS: Under continuous electrocardiographic Holter monitoring, 42 patients were randomly scheduled to receive either normothermic (33.5 degrees C) or hypothermic (10 degrees C) cardioplegia solutions during coronary bypass grafting surgery. Blood samples for creatinine phosphokinase, creatinine phosphokinase-MB, lactate, epinephrine, and norepinephrine were withdrawn during cardiopulmonary bypass via a coronary sinus cannula. RESULTS: Active cooling in group H on initiation of cardiopulmonary bypass was characterized by transition through ventricular fibrillation in 75% of patients, whereas in group N atrial fibrillation occurred in 65% of patients. On myocardial reperfusion, sinus rhythm spontaneously resumed in 95% of group N patients compared to 25% in group H (P = 0.0003). In the latter, 75% of patients developed ventricular fibrillation often followed by complete atrioventricular block, which necessitated temporary pacing for a mean duration of 168 +/- 32 min. Both groups showed a similar incidence of intraventricular block and ST segment changes. However, the incidence of ventricular premature beats in the first 16 h after cardiopulmonary bypass was significantly greater in group H (P < 0.05), 20 +/- 26/h, compared to 3 +/- 5/h in group N. Blood concentrations of lactate, creatinine phosphokinase, epinephrine, and norepinephrine increased gradually during the operation, but the differences between the groups were not significant. CONCLUSIONS: The current prospective human study suggests that the increased susceptibility for ventricular fibrillation and dysrhythmia, and the delayed recovery of the conduction system after hypothermic myocardial protection, are related to temperature-induced changes in vital cellular functions of the conduction tissue in the postischemic period. Both cardioplegic methods provide adequate myocardial protection but normothermic oxygenated blood cardioplegia may accelerate recovery of the heart after cardiopulmonary bypass.

Adult↗
PubMed1996

Early experience in lung transplantation.

Lung transplantation is becoming an acceptable mode of therapy worldwide for the end-stage lung disease. We present our initial experience with the first 10 consecutive lung transplant patients at Hadassah University Hospital. There were 5 males and 5 females with an age range 27 to 59 years. Eight patients underwent single lung transplantation, one patient had double lung transplantation and one had heart-lung transplantation. Indications were: pulmonary fibrosis in 4, emphysema in 4, cystic fibrosis in 1, and cystic bronchiectasis in 1. Two patients had primary graft failure (1 death). Nine patients had a serious infection after transplantation (1 death). Four patients developed airway complications including dehiscence of bronchial anastomosis (1 death), bronchial stenosis requiring placement of a stent in 2 patients, and pneumothorax in 1 patient. One patient required tracheostomy. One patient died of massive brain infarction secondary to pulmonary venous thrombosis and embolization. Six patients are intermediate-term survivors, with a follow-up period of 4-24 months. Four of them had at least one episode of rejection each. In all survivors pulmonary functions and quality of life improved and they do not need supplemental oxygen. We conclude that lung transplantation is a viable option for end-stage lung disease. Better selection of patients and perhaps improved immunosuppression agents will further improve outcome in lung transplantation. Shortage of donor supply is currently the limiting factor in successful lung transplantation in Israel.

Adult↗
PubMed1993

Warm blood cardioplegia for patients undergoing revascularization for left main coronary artery disease.

Between February 1991 and June 1992, 62 patients (50 males) underwent coronary artery bypass (CAB) operation for significant left main coronary artery disease. Age varied between 47 and 81 years. 53 patients had unstable angina, 16 had recent myocardial infarction, and 16 had heart failure. 22 patients were in functional capacity class IV (Canadian Heart Association) and 2 patients were in unstable hemodynamical condition before the operation. Intraaortic balloon pump was inserted before the operation in 3 patients. Six patients had previous CAB surgery. All the patients were operated using myocardial protection with warm blood cardioplegia, given antegradely and retrogradely in 58 and only antegradely in 4 patients. Body temperature was maintained at 30 +/- 1.8 degrees C. Number of distal anastomoses averaged 4.3 +/- 0.9. One patient underwent additional resection of a left atrial myxoma and another aortic valve replacement. LIMA (left internal mammary artery) was used to bypass the LAD in 58 (94%) patients. Early mortality was 3 cases (4.8%). Major and minor postoperative complications occurred in 17 patients. These data suggest that warm blood cardioplegia provides superior myocardial protection in patients with left main coronary artery disease.

Aged↗
PubMed1991

Coronary pathology predicts conduction disturbances after coronary artery bypass grafting.

Conduction disturbances after coronary artery bypass grafting may result from compromised septal blood flow. To examine this hypothesis we reviewed the preoperative coronary angiography of 55 consecutive patients undergoing coronary artery bypass grafting. Thirty-five patients had either no lesion or a discrete lesion in the left anterior descending coronary artery that did not include the septal perforator (type I anatomy). Twenty patients had a lesion of the left anterior descending coronary artery at the origin of the first septal branch, a lesion of the first septal artery, or a pair of lesions in the left anterior descending coronary artery that straddled the origin of the first septal artery; all lesions were proximal to the graft site (type II anatomy). None of the patients with type I anatomy had a major conduction disturbance after coronary artery bypass grafting. Eleven of the patients with type II anatomy had major conduction disturbances after coronary artery bypass grafting; right bundle-branch block in 1, right bundle-branch block and left anterior hemiblock in 2, left bundle-branch block in 5, and complete atrioventricular block that required pacemaker implantation in 3 (p less than 0.001). In the 20 patients with type II anatomy, the appearance of conduction disturbances correlated well with the absence of retrograde flow to the septal branches from the right coronary artery (p less than 0.01). Pathological lesions in the left anterior descending coronary artery that compromise flow in the first perforator and that do not provide an adequate circulation produce localized damage and conduction disturbances after coronary artery bypass grafting. This can be predicted from the preoperative angiographic anatomy.

Aged↗
PubMed1990

[Surgical pulmonary embolectomy and thrombolytic therapy].

Acute, massive pulmonary embolism is life-threatening and must be treated immediately. Since the early 1970's when thrombolytic therapy was shown to hasten resolution of pulmonary emboli, there has been a debate in the literature as to new indications for surgical pulmonary embolectomy. Some authors believed that there are no longer any indications for embolectomy, while others justify surgery for certain indications. Although the debate is still on, this operation is very rarely performed today. We present a patient who developed massive pulmonary embolism, with continuing extreme hemodynamic and respiratory disturbances despite full thrombolytic treatment. Embolectomy was successfully performed.

Female↗
PubMed1983

Early postoperative assessment of coronary artery bypass surgery using nuclear left ventriculography and atrial pacing.

Nuclear ventriculography (MUGA) was performed in 22 patients at rest and during the stress of right atrial pacing 6 to 8 days after coronary artery bypass surgery. In 7 patients the MUGA-atrial pacing test was positive for ischemia with chest pain, electrocardiographic ST depression and/or a decrease in global left ventricular ejection fraction of greater than 10%. All 7 patients subsequently developed angina pectoris with a positive treadmill test (performed at a median time of 14 months after operation). In 15 patients, the early postoperative MUGA-atrial pacing test was negative. In this group, 3 patients subsequently developed angina pectoris with a positive treadmill test in one. The sensitivity of the 'one week' early postoperative MUGA-atrial pacing in the identification of patients with residual myocardial ischemia was high (88% for positive GXT, p less than 0.0001; 70% for chest pain, p less than 0.005) with 100% specificity. The early postoperative MUGA scan was also useful in predicting later shortness of breath on exertion and there was a significant correlation between the early resting ejection fraction and the exercise capacity of the patient subsequently. The information obtained from an early postoperative MUGA-atrial pacing study may have far-reaching and important practical application in selecting patients for early recatheterization, possible fibrinolysis and/or possible cardiac reoperation.

Adult↗
PubMed1982

Intraaortic balloon counterpulsation in acute myocardial infarction.

Intraaortic balloon counterpulsation was undertaken in 24 patients with acute myocardial infarction. The patients were divided into four groups: severe left ventricular dysfunction (11 patients), mechanical lesions (6), intractable angina pectoris (6) and refractory ventricular tachycardia (1). The clinical condition and the hemodynamic measurements improved dramatically in 21 patients, but there were only 9 long-term survivors. Intraaortic balloon counterpulsation gave the best results in patients with preinfarction angina pectoris or patients with left ventricular dysfunction where the hemodynamic status deteriorated after an acute but reversible cardiovascular event. Numerous local complications were observed.

Adult↗