Gerard S. Kakos

Reoperative coronary artery bypass grafting without cardiopulmonary bypass.

Between June 1979 and January 1992, 46 men and 13 women aged 35 to 81 years (mean, 58 years) underwent reoperative coronary artery bypass grafting without cardiopulmonary bypass. Isolated reoperative circumflex bypass was performed through a left thoracotomy, and reoperative bypass to the right coronary artery and left anterior descending coronary systems was through a median sternotomy. Complete revascularization was the goal in all patients. Saphenous vein grafts were placed to the right coronary artery (n = 21), circumflex artery (n = 11), and left anterior descending artery (n = 24), and 14 internal thoracic artery to left anterior descending artery bypass grafts were performed. The overall mortality rate was 3.4% (2 deaths). Postoperative morbidity included myocardial infarction in 1 patient and pleuropulmonary complications in 6. No patient was reexplored for hemorrhage, and 19 patients required no blood products. Twenty patients underwent repeat coronary angiography, and 18 of 20 grafts placed without cardiopulmonary bypass were patent. At a mean follow-up interval of 42.2 months 35 of 50 evaluable patients were in functional class I or II. In selected patients, reoperative coronary artery bypass grafting can be performed without cardiopulmonary bypass with a low perioperative morbidity and mortality rate, satisfactory graft patency rates, and good long-term symptomatic improvement.

Potential effect of lidocaine on ischemic myocardial injury: experimental and clinical observations.

The effect of lidocaine on ischemic myocardial injury was studied in acute myocardial infarction (AMI). In 20 anesthetized dogs coronary artery ligation (CAL) was performed. Dogs were divided into three groups. Group I (n = 8) had CAL only, Group II (n = 6) received 3 mg/kg of lidocaine (L) 30 min post-CAL, Group III (n = 6) received the same bolus injection of L and an L infusion of 2 mg/min for 120 min. In Group I the sum of ST segment elevation (Σ ST) and the number of sites showing >1 mV ST elevation (NST), as measured from epicardial mapping, were unchanged between 30 and 150 min post-CAL, the mean R magnitude decreased significantly, and 12 new Q waves were recorded. In Groups II and III, 15 min after L administration, Σ ST and NST decreased significantly (P < 0.05) and remained unchanged until the end of the study. There was no difference in Σ ST and NST changes between Groups II and III. No R wave magnitude changes or Q waves were observed between 30 and 150 min post-CAL in Groups II and III. Coronary sinus CPK at 150 min post-CAL increased more in Group II than in Group I (23 ± 3 vs 49.7 ± 9, P < 0.05). A negative inotropic effect was demonstrated by decreases in peak dp/dt (510 ± 50 mm Hg/sec, P < 0.05) and dQ/dt (28 ± 2%, P < 0.05) 5 min after the L bolus. This effect of lidocaine on Σ ST and NST was studied in six patients with anterior AMI. L decreased significantly both Σ ST and NST in the patients studied. These data suggest that lidocaine has a beneficial effect, decreasing ischemic injury and/or delaying the process of ischemic necrosis. This appears to be caused by a negative inotropic effect, which may be beneficial in the early post-open-heart surgery period and in patients with acute myocardial infarction.

The use of cautery in “bloodless” radical mastectomy

Several different forms of operative procedures for carcinoma of the breast have been advocated, but radical mastectomy remains the one most often recommended. Blood loss during this procedure is frequently high, often necessitating transfusion. Unfortunately, complications of the latter have been significant and justifiably have continued to receive attention in literature. In this study, blood loss and wound healing, with and without the use of electrocautery, in radical mastectomy were evaluated from both clinical and laboratory studies. Fifty patients who underwent radical mastectomy were studied for blood loss, transfusions received, and wound healing. Technique was identical except that one half of the patients had thin skin flap elevation via electrocautery rather than by sharp dissection. The average blood replacement was 160 ml per patient when cautery was used vs. 960 ml per patient when cautery was not used. The postoperative hemoglobin and hematocrit values were statistically similar for both groups. Wound healing was not affected. In addition, a laboratory study, utilizing skin incisions in dogs using scalpel and cautery, was performed. No appreciable difference in healing was noted either on gross or microscopic inspection. The use of electrocautery, therefore, for skin flap elevation during radical mastectomy is recommended.

The effect of ischemia on canine carotid endothelial permeability

The effect of ischemia on arterial endothelial permeability was assessed by surgically interrupting arterial blood flow for 45 min in the left carotid artery of 12 foxhounds. The right carotid artery served as control. Twenty-four hours before sacrificing the animals at 1 day, 1 week, 1 month, and 3 months postoperatively. Evans blue dye (1.5 ml/kg) was administered intravenously. Carotid arteries were harvested, opened, and scanned with a reflectometer to measure Evans blue dye uptake, and scanning electron microscopy was performed on a section of tissue from each harvested vessel. A statistically significant increase in permeability of the ischemic vessel occurred at 1 day (79 +/- 42% (SD], 1 week (186 +/- 75%), and 1 month (229 +/- 125%), but was not present at 3 months (7 +/- 8%) postinjury. Scanning electron microscopic examination of all specimens was essentially normal. This study demonstrates that arterial endothelium has increased permeability at 1 month following a brief ischemic period. What effect this ischemia-induced endothelial dysfunction will have on lipid uptake by the arterial wall will be the subject of future study.

Hemangiopericytoma: A case report and rationale for aggressive therapy

Hemangiopericytomas are infrequently encountered neoplasms which exhibit growth and recurrence potentials distinct from other vascular tumors. Late recurrence (greater than 5 years) is not uncommon, and the over‐all metastasis rate approximates 50%. An aggressive approach is indicated for these tumors, as both radiation therapy and chemotherapy seem to be of little benefit. A case in which the primary lesion arose in the meninges, followed by pulmonary and hepatic metastasis, resected 11 and 16 years, respectively, after the primary tumor is presented. The patient is currently alive and asymptomatic without evidence of additional tumor.

Influence of Cardiopulmonary Bypass on Nitroglycerin Clearance

The effect of cardiopulmonary bypass on the clearance of nitroglycerin (NTG) was studied in seven patients scheduled for coronary artery bypass graft surgery. Intravenous NTG was administered through nonadsorbing tubing at a starting dosage of 5–10 μg/min and was adjusted as needed. Blood samples were obtained from the radial artery and antecubital vein before bypass and from the arterial outlet of the oxygenator during bypass at least 30 minutes apart during a constant dosage or at least 30 minutes after a dosage change. Serum concentrations were analyzed for NTG by gas chromatography. Venous NTG concentrations were always lower than concurrent arterial concentrations, with an average arteriovenous extraction of 67.2%. Serum concentrations of NTG were generally within the range associated with a therapeutic response in congestive heart failure patients. Consistent with other reports, NTG concentrations varied widely among patients and considerable intrasubject fluctuations in drug concentrations were seen. The mean ± SD apparent clearance of NTG before bypass of 0.044 ± 0.02 L/kg/min increased 20% to 0.052 ± 0.02 L/kg/min during bypass (P = .05). These results suggest that cardiopulmonary bypass increases the clearance of NTG; however, the magnitude appears to be small and only partially explains the reported increased dosage needed during cardiopulmonary bypass.

Counterpulsation Catheter Fracture: An Unexpected Hazard

This paper presents a previously unrecognized hazard associated with intraaortic balloon pumping: fracture of the catheter due to chemical damage by acetone at the time of removal. Common hospital chemicals such as acetone, ether, and Vi-Drape spray may damage the catheter. Contact between these agents and polyurethane intraaortic balloon catheters should be avoided during dressing changes or repreparation of a sterile operative field. Isopropyl alcohol, Betadine, benzoin, and Cidex do not damage the catheter.

Diagnosis and Management of Sinus of Valsalva Aneurysm in Children

Abstract Aneurysm of the sinus of Valsalva is an uncommon congenital lesion rarely reported in children. Because of the significant incidence of other associated cardiac anomalies and the general lack of symptoms when the aneurysm is unruptured, early diagnosis and subsequent management may be difficult. Three children who underwent operative repair are presented with reference to their pathological, diagnostic, and therapeutic courses. The need to preserve the aortic valve in younger children is emphasized, as is the excellent relief of clinical symptoms and laboratory abnormalities by corrective operation.

Protective effect of β-adrenergic blockade and hypothermia on myocardial ultrastructure

Abstract Open heart surgery requiring cardiac arrest without coronary artery perfusion may result in significant myocardial damage. The relative myocardial preservative effects of pretreatment with hypothermia and/or β-adrenergic blockade were analyzed using 24 dogs subjected to 1 hr of ischemic cardiac arrest and comparing them to 8 nonischemic animals. The dogs were divided into six groups as follows: Group 1, normal coronary perfusion; Group II, cardiopulmonary bypass; Group III, ischemic cardiac arrest without pretreatment; Group IV, ischemic arrest with hypothermia (28°C systemic plus local hypothermia); Group V, ischemic arrest with β-adrenergic blockade (2.5 mg/kg iv practolol, 15 min prearrest); Group VI, ischemic arrest with hypothermia and practolol. Ischemic damage was assessed with electron microscopy by the use of full thickness myocardial biopsies. Micrographs were analyzed quantitatively using a morphometric technique for estimation of cytoplasmic structures. Ischemic injury was indicated by the relative proportion of sarcoplasm to myofibrillar volume. Statistical analysis showed that pretreatment with both hypothermia and β-adrenergic blockade was more effective in reducing ischemic cardiac injury than by the use of either hypothermia or β-adrenergic blockade individually.

Effect of paired ventricular pacing upon myocardial infarction size.

Abstract Although paired ventricular pacing may improve cardiodynamics following acute myocardial infarction, its effect on myocardial infarct size is not known. In 22 dogs, acute myocardial infarction was produced by selective coronary artery ligation. High fidelity left ventricular pressure, dp dt max , acceleration of aortic flow ( dQ dt ), coronary flow and epicardial mapping were recorded before and at 15-min intervals following acute myocardial infarction for a total of 90 min. Coronary sinus CPK was measured before coronary occlusion and then every 30 min for a period of 150 min. In Group A (n = 10) animals had an acute myocardial infarction only, while in Group B (n = 12), paired ventricular pacing was initiated 30 min postinfarction and continued throughout the study. Two dogs from Group A and six from Group B developed ventricular fibrillation and were excluded from the study. In Group A dp dt p , dQ dt and heart rate did not change, while in Group B dp dt p increased from 20.0 ± 1.5 to 30.2 ± 1.5 (P dQ dt increased from 19.0 ± 1.7 to 27.1 ± 2.5 (P These data indicate that paired ventricular pacing increased ischemic injury in acute myocardial infarction, due to increased oxygen consumption resulting from the positive inotropic effect exceeding the influence of a decreased heart rate.