Intraoperative and laboratory evaluation of skeletonized versus pedicled internal thoracic artery.

BACKGROUND: The skeletonization of internal thoracic artery is postulated to improve graft length, early blood flow, sternal blood supply, and postoperative respiratory function. Concern exists that skeletonization may injure internal thoracic artery, precluding good results of surgery. Reports on endothelial function of skeletonized internal thoracic artery are lacking. METHODS: A prospective assessment of early clinical outcomes of 357 consecutive patients undergoing coronary artery bypass grafting was performed: 287 patients with nonskeletonized and 70 with skeletonized left internal thoracic artery (LITA). The lengths of LITA and of its discarded distal segment, as well as free LITA blood flow, were measured. The dose-effect relationship for relaxation to acetylcholine was studied in the organ bath. RESULTS: Apart from a higher incidence of breaching the pleura with nonskeletonized LITA the clinical outcomes were comparable. The length of skeletonized LITA was 17.8+/-1.14 cm versus 20.3+/-0.52 cm skeletonized (p = 0.11). The length of discarded LITA was shorter in nonskeletonized artery (0.8+/-0.28 cm versus 2.6+/-0.49 cm; p = 0.022). The free LITA blood flow was 66.3+/-7.42 mL/min in nonskeletonized vessel versus 100.3+/-14.84 mL/min in skeletonized (p = 0.048). The acetylcholine-induced relaxation was similar in both groups (maximal relaxation, 80.7%+/-5.95% in nonskeletonized versus 72.9%+/-9.11% in skeletonized; not significant; negative logarithm of half-maximal effect, 7.43+/-0.18 versus 7.1+/-0.10, respectively; p = 0.063). CONCLUSIONS: Skeletonization does not damage the endothelial function of the LITA. Higher free blood flow and available LITA length should encourage the use of skeletonized LITA in clinical practice.

Coronary artery bypass grafting without cardiopulmonary bypass--initial experience of 50 cases.

This study was undertaken to assess our experience with the first 50 patients who underwent CABG without cardiopulmonary bypass. In seven patients left internal mammary artery to left anterior descending artery (LIMA-LAD) grafting was performed through a short left anterior thoracotomy. In 43 other patients median sternotomy was used. Primary CABG was performed in 48 patients; there were two reoperations. Eleven patients had unstable angina. Three patients had left ventricular ejection fraction (LVEF) equal to or lower than 25%. One patient had carcinoma of the right lung coexisting with unstable angina and underwent also right lower lobectomy. In each patient the clinical course, 12-lead ECG, transthoracic echocardiography and the serum levels of creatine kinase (CPK), alanine aminotransferase (ALAT), aspartate aminotransferase (AspAT) were assessed. The need for inotropic or intraaortic balloon counterpulsation (IABP) support and blood transfusion was also recorded. There were three deaths, all in the sternotomy group (6%). A patient with systemic lupus erythemetodes (SLE) died of postoperative MI due to graft thrombosis. Another patient who was found to have porcelain aorta and had LIMA-LAD grafting as a rescue procedure died of MI with low cardiac output. The third patient with unstable angina and ejection fraction of 30% developed postoperative MI with ventricular arrhythmia. One patient with LIMA-LAD graft in whom percutaneous translaminal coronary angioplasty (PTCA) had been abandoned because of coronary spasm developed acute myocardial ischaemia 5 h postoperatively. He had a vein graft placed to LAD in cardiopulmonary bypass, his further course was uneventful. Six patients had IABP support. Nine patients needed inotropic support. Ten patients received blood transfusion. Twelve-lead ECG did not show acute ischaemia or MI, apart from the above described cases. Echocardiographic check showed improved IVS contractility in three patients and better apex motion in one case. In the other survivors the echocardiographic findings were the same as before the procedure. ALAT and AspAT serum levels were normal in all the survivors, and the CPK levels did not exceed 200 IU/ml. One patient from the mini-thoracotomy group had recurrent angina 2 months after the procedure. His left internal mammary artery (LIMA) graft was occluded; we replaced it with a vein graft. All 47 survivors remain asymptomatic, with the mean follow-up time of 6 months. Coronary surgery without cardiopulmonary bypass seems a valuable alternative for high-risk patients.

Comparison of retrograde versus antegrade cold blood cardioplegia: randomized trial in elective coronary artery bypass patients.

OBJECTIVE: Myocardial areas distal to complete coronary artery occlusion are poorly protected by antegrade cardioplegia. Hence, retrograde cardioplegia becomes an important adjunct in myocardial protection. An aim of the study was to compare both methods prospectively. METHODS: 158 coronary artery bypass grafting (CABG) patients were randomly assigned to two groups according to myocardial protection technique: 89 patients to group 1--retrograde cold blood cardioplegia (RCBC); and 69 patients to group 2--antegrade cold blood cardioplegia (ACBC). Preoperative parameters were similar but cross-clamp time and volume of cardioplegia needed were higher in the retrograde group. The results were assessed on the basis of: (1) clinical outcome; (2) ECG and enzymatic parameters of ischemia; (3) assessment of early systolic function by means of cardiac output (CO), stroke work index (SWI), left ventricular stroke work index (LVSWI) and right ventricular stroke work index (RVSWI) taken before, and 1 and 5 h after coming off bypass; (4) late systolic and diastolic function by echo assessment of segmental contractility of 17 segments and indexes of peak transmitral flow (TMI) taken 7 days and 6 months after operation. RESULTS: Ischemic events, inotropes and ventricular fibrillation on reperfusion were significantly more frequent in the antegrade group. Sinus rhythm at an early stage postoperatively was found more frequently in the retrograde group. All these parameters became comparable 24 h after operation. Early myocardial recovery was better in the retrograde group where intraoperative improvement in CO and SWI was significant. At the same time, SWI decreased significantly in the antegrade group. RVSWI changes were similar in both groups. There were no differences in mortality and perioperative MI. Late myocardial performance by segmental contractility and diastolic transmitral flow were similar in both groups. CONCLUSIONS: Retrograde continuous blood cardioplegia reduces ischemic injury and permits better early recovery of myocardial function. There is no difference, however, regarding long-term assessment of myocardial recovery.

Results of mechanical prosthetic valve replacement in active valvular endocarditis.

UNLABELLED: To evaluate the results of mechanical prosthetic valve replacement for active endocarditis 71 patients were reviewed. They were treated surgically between 1988 and 1993 in our institution. Mechanical valves were used in 54 patients (group 1) and bioprosthetic valves were used in 17 patients (group 2). In terms of demographic, clinical and surgical variables prior to operation groups were statistically the same. Follow up ranged from 2-63 months averaged 21 months. This study was carried out to: asses cardiac status postoperatively and assess the rate of mortality, recurrency and reoperations. METHODS: Evaluation of cardiac status was assessed on the basis of symptoms and findings by examination, ECG, X-ray, echocardiography, and laboratory tests. Data analysis was done by means of statistical tests like: Student's "t"-test, Fisher exact test, one sided test of difference between two percentages, Kaplan Meyer survival analysis and Cox test. RESULTS: 4-year mortality was 20% in group 1 comparing to 28,6% in group 2, when early mortality were 13% in group 1 comparing to 17% in group 2. These differences were not significant. The recurrency rate was 8,5% in group 1 comparing to 28,6% in group 2 which was statistically significant (p=0.028). Especially early recurrency rates differed significantly between groups and were 4,2% in group 1 comparing to 21% in group 2 (p=0.022). The reoperations rate was 4,2% in group 1 comparing to 21% in group 2 which was statistically significant (p=0.022). Clinical status showed satisfactory values and significant improvement in both groups, slightly better after mechanical valve replacement. CONCLUSION: It is concluded that mechanical valve is recommended for valve replacement in active valvular endocarditis first of all due to low recurrency and reoperation rate.

Surgical treatment of atrial septal aneurysm.

The atrial septal aneurysm (ASA) is a morphologic abnormality known to cause peripheral and pulmonary embolism. 28-52% patients with ASA have embolic events. However ASA -- with no other concomittant cardiac patology has rarely been reported as the indication for open heart surgery. In this work, five cases of patients operated for ASA are presented. Embolic complications with cerebral symptoms were presented in three cases. The diagnosis of ASA was established with the use of transesophageal echocardiography. The surgical correction of the defect was performed in extracorporeal circulation. The aneurysmal part of interatrial septum was excised and replaced with a pericardial patch. The postoperative course was uneventful. The patients have no new embolic events during the follow up period of one year.

Ruptured aneurysm of the sinus of Valsalva. Clinical review, treatment results.

Five patients were operated on because of ruptured aneurysm of the sinus of Valsalva. In the cases with no concomitant VSD the surgical access from the aorta was used. The aorta was opened and the Fogarty catheter was introduced to the fistula. The "wind sock" of the aneurysm was pulled back to the aorta and excised. The opening was closed with double-line pledgetted polypropylene sutures. In severe aortic incompetence mechanical prostheses were implanted. One patient had bacterial endocarditis with reopening of the fistula and aortic valve incompetence that required reoperation. All patients are in a good clinical state. We recommend the use of Dacron patches even in small aneurysms to avoid re-opening of the fistula.