Bruce B. Davis

Improved Preservation of Saphenous Vein Grafts by the Use of Glyceryl Trinitrate–Verapamil Solution During Harvesting

BACKGROUND High-pressure distension during harvesting damages the saphenous vein (SV) and may contribute to subsequent coronary artery bypass graft (CABG) occlusion. Application of vasodilator agents to the SV during harvesting may reduce the need for high-pressure distension and improve graft quality. We tested the effects of a vasodilator solution containing glyceryl trinitrate and verapamil (GV) or the conventional agent papaverine (Pap) on the pressure necessary to overcome SV spasm and on the structure and biochemistry of the SV graft. METHODS AND RESULTS Thirty-six patients undergoing CABG were randomly allocated to receive an application of either topical and intraluminal GV solution, topical Pap, or topical and intraluminal Ringers solution (untreated) to the SV during harvesting. The peak and mean pressures required to distend the vein were recorded. Samples of SV were taken for microscopy and biochemical analysis just before we performed the anastomosis. The percentage of endothelial coverage was calculated by area measurements of stained en face preparations of the vein intima. The results for peak pressures (mmHg) were: untreated, 479.2 +/- 27.5; Pap, 384.8 +/- 29.0; and GV, 309.5 +/- 28.3 (P < .001, GV plus Pap versus untreated); and the results for mean pressures (mm Hg) were untreated, 136.2 +/- 9.6; Pap, 102.2 +/- 10.8; and GV, 98.0 +/- 8.3 (P < .01, GV plus Pap versus untreated). The results for endothelial cover (%) were: untreated, 43.7 +/- 7.0; Pap, 44.1 +/- 9.2; and GV, 68.7 +/- 7.0 (P < .05, GV versus Pap); and the results for ATP (nmol/g wet wt) were: untreated, 67.3 +/- 12.7; Pap, 112.0 +/- 19.4; and GV, 132.5 +/- 22.7 (P < .05, GV plus Pap versus untreated). CONCLUSIONS First, pharmacological treatment of SV during harvesting, especially with GV solution, allows the use of a lower distension pressure and reduces the breakdown of high-energy phosphates in the vein wall. Second, topical and intraluminal use of GV solution during vein harvesting improves endothelial coverage compared with the topical use of Pap or no pharmacological treatment.

Hemodynamic effects, myocardial ischemia, and timing of tracheal extubation with propofol-based anesthesia for cardiac surgery

Recent interest in earlier tracheal extubation after coronary artery bypass graft (CABG) surgery has focused attention on the potential benefits of a propofol-based technique. We randomized 124 patients (34 with poor ventricular function) undergoing CABG surgery to receive either a propofol-based (5 mg [center dot] kg-1 [centered dot] h-1 prior to sternotomy, 3 mg [center dot] kg-1 [center dot] h (-1) thereafter; n = 58) or enflurane-based (0.2%-1.0%, n = 66) anesthetic. Induction of anesthesia consisted of fentanyl 15 micro g/kg and midazolam 0.05 mg/kg intravenously in both groups. The enflurane group received an additional bolus of fentanyl 5 micro g/kg prior to sternotomy and fentanyl 10 micro g/kg with midazolam 0.1 mg/kg at commencement of cardiopulmonary bypass (CPB). Patients receiving propofol were extubated earlier (median 9.1 h versus 12.3 h, P = 0.006), although there was no difference in time to intensive care unit (ICU) discharge (both 22 h, P = 0.54). Both groups had similar hemodynamic changes throughout (all P > 0.10), as well as metaraminol (P = 0.49) and inotrope requirements (P > 0.10), intraoperative myocardial ischemia (P = 0.12) and perioperative myocardial infarction (P = 0.50). The results of this trial suggest that a propofol-based anesthetic, when compared to an enflurane-based anesthetic requiring additional dosing of fentanyl and midazolam for CPB, can lead to a significant reduction in time to extubation after CABG surgery, without adverse hemodynamic effects, increased risk of myocardial ischemia or infarction. (Anesth Analg 1997;84:12-9)

Occlusive wrap dressing reduces infection rate in saphenous vein harvest site

BACKGROUND Infection in the saphenous vein harvest site is a common problem. We developed an occlusive circumferential wrap dressing technique that reduces skin edge tension, eliminates dead space, and prevents external contamination. We compared the surgical site infection rate using the wrap dressing technique with that of standard longitudinal dressings. METHODS. One hundred fifty-two consecutive patients were randomly assigned to receive either standard dressings or the wrap dressing. Data were collected in the hospital and then 4 to 6 weeks postoperatively. Superficial and deep wound infections were defined by the standard criteria from the Centers for Disease Control and Prevention. RESULTS The infection rate in the wrap group was 14% compared with 35%, for the standard group (p = 0.006). Multivariate analysis showed that wrap technique was the only significant predictor (negative) of infection (odds ratio, 0.19; p = 0.001). CONCLUSIONS In saphenous vein harvest wounds, the occlusive wrap dressing technique has the potential to reduce the rate of infection by 50%. This simple and inexpensive technique is also readily applicable to the radial artery harvest site in the arm and may provide similar benefit.

Surgical management of carcinoid heart disease

Metastatic carcinoid tumor is often seen with flushing, diarrhea, and cardiac symptoms--the carcinoid syndrome. Cardiac failure is often associated with major morbidity and mortality in carcinoid disease. In this report, a case of successful cardiac valvar surgical intervention has resulted in prolonged alleviation of cardiac symptoms and survival.

A new technique for relaxing the saphenous vein during harvesting for coronary bypass grafting

Abstract We describe a technique of treating the saphenous vein with a new vasodilator solution during harvesting for coronary bypass grafting. In a previous study, glyceryl trinitrate (GTN) and verapamil caused full relaxation of the vein. When used in combination, these agents caused a rapid onset (due to GTN) and long duration of action (due to verapamil). We routinely apply this solution to the inside and the outside of the saphenous vein during harvesting to provide a relaxed venous conduit for coronary bypass grafting.

Dissection of an allograft ascending aorta after aortic root replacement

THe case of a 57-year-old man with dissection of an allograft ascending aorta 2 months after aortic root replacement is presented. Most likely traumatic in origin, this unusual complication was managed by Dacron graft replacement of the ascending aorta using hypothermia and circulatory arrest.

Left ventricular aneurysmectomy: A comparison of linear and circular repairs

Abstract Aim: To review the long-term results of left ventricular aneurysmectomy in the Alfred Hospital, and to compare the results of circular versus linear repair. Method: The hospital records of 94 patients who were referred for left ventricular aneurysmectomy between July 1984 and June 1994 were reviewed. Seven patients did not have an aneurysm at operation and were excluded. Eighty-seven remaining patients were divided into 2 groups: circular plasty repair and linear repair. The 2 groups were matched for age, sex, functional class, and indications for operation. A standard ventriculographic grading system for left ventricular function was used for all patients. Follow-up studies conducted until August 1995 and a standard questionnaire was completed for each patient. Results: The mean age of patients was 59.35 years. Twenty patients (23%) had symptoms specific to the aneurysm (heart failure, thromboembolism, arrhythmia). Sixty-three patients (72.4%) were in New York Heart Association (NYHA) class III and IV. Left ventricular function was recorded as grade II and III in 48 (67.6%) and IV in 22 (31%) patients. Circular repair was used in 41 (47.1%) patients and linear repair in the others. Coronary artery bypass was deemed unnecessary in 11 patients. Postoperative gated blood pool scan in 12 patients showed improvement in ejection fraction in 7 patients (58.3%). Early mortality was 5.7%. Mean follow-up was 52.8 months with a range of 4–121 months. Seventeen patients (77.2%) in the circular and 13 patients (43.3%) in the linear repair group were in NYHA class I and II at latest follow-up. Actuarial 5 and 10-year survivals were 75% and 58%, respectively. Survival figures for linear repair versus circular repair with or without coronary artery bypass did not show any significant difference. Conclusion: Our data show good short-term and long-term results, with patients undergoing circular repair experiencing significantly better improvement in exercise tolerance.

Pulmonary embolectomy in the management of massive pulmonary embolism

Abstract This paper reports the Alfred Hospital experience with pulmonary embolectomy in the management of 61 patients with massive pulmonary embolism over a 26-year period. All operations were performed on cardiopulmonary bypass. Mortality was 16% in patients who had not sustained a cardiac arrest preoperatively (n=44), and 59% in those who had arrested (n=17). Pulmonary embolectomy for massive pulmonary embolism can be performed safely and may be the treatment of choice in the patient with circulatory instability. In the patient who has sustained a cardiac arrest from pulmonary embolism, embolectomy offers the only hope in a desperate situation.

Repair Of postmyocardial infarct ventricular free wall rupture using an onlay pericardial patch

Abstract Background : Acute cardiac rupture is a life-threatening complication of acute myocardial infarction. Traditional methods of surgical treatment by infarctectomy with mattress suture repair are associated with a high mortality. Recently, new approaches involving an onlay patch without infarctectomy have been introduced with promising results. Our previous experimental work showing that the recently infarcted myocardium recovers poorly after aortic cross-clamping and cardioplegic arrest suggested that repair of rupture using ventricular fibrillation is preferable. Methods and Results : We report 4 consecutive patients who have been successfully treated using a technique involving an onlay patch of pericardium secured with glue and a circumferential suture. In 2 cases it was possible to complete the repair without cross-clamping the aorta. Conclusion : Ventricular rupture can be successfully repaired using an onlay patch and repair can be accomplished without the use of cross-clamping or cardioplegia.

An unusual tumour involving heart and liver

Abstract We report the successful removal of a large right atrial haemangioma associated with multiple liver haemangiomas. Preoperative echocardiography showed a large right atrial mass, and computerised tomography revealed lesions in the liver. A preoperative diagnosis of malignant cardiac tumour and liver secondaries was made. However, the tumour was benign. This case emphasises the need to obtain a definitive histologic diagnosis preoperatively, if possible, before rejecting a patient for surgery, and to be aware that benign lesions can be multifocal.