Comparison of neurological outcomes in patients undergoing conventional coronary artery bypass grafting, on-pump beating heart coronary bypass, and off-pump coronary bypass.

OBJECTIVE: To study the differences in the prevalence of neurological complications following coronary artery bypass (CAB) carried out by conventional, on-pump beating and off-pump techniques. METHODS: A retrospective analysis of all isolated coronary bypass operations (n=127) performed in King Fahad Cardiac Center, Riyadh over a period of one year starting from January 2005. Out of 127 patients, 73 underwent conventional CAB graft (CABG), 33 patents on-pump beating heart coronary bypass, and 21 had off pump coronary bypass grafting (OPCAB). All patients had preoperative carotid scans and those who developed neurological complications underwent CT-brain and expert neuro-psychiatric assessment. RESULTS: Preoperative characteristics of patients in all 3 groups were similar. The bypass times in the conventional CABG group were significantly longer than the on-pump beating group. The maximum number of grafts was in the on-pump beating group, followed by the conventional CABG, and the least in the OPCAB group. Seven out of 73 cases in the conventional bypass group developed neurological events of various severities. Only one out of 33 patients developed acute confusional state in the on-pump beating group and no neurological events were noticed in 21 patients operated by the OPCAB technique. Low ejection fraction, preoperative congestive cardiac failure, non-elective surgery and preoperative catastrophic state were found to be significant risk factors independent of the bypass technique. CONCLUSION: This study shows no significant difference in the prevalence of neurological complications among different types of bypass surgery in our institution. There was a trend towards less neurological outcomes in the OPCAB and on-pump beating groups.

Intra-operative heparin release during lung surgery.

OBJECTIVES: Heparin has long been thought to be biosynthesized and stored in the granules of mast cells that are most prevalent in the lungs and gastro-intestinal tract. In response to stimuli such inflammation and trauma, mast cells degranulate and consequently release heparin. This prospective study was designed to investigate if operative trauma during lung mobilization could enhance heparin release into both the pulmonary and systemic circulations. METHODS: Prospective investigations and data collection were carried out on 34 patients undergoing elective thoracotomies for 19 patients with chronic inflammatory disease and 15 with lung carcinoma. Heparin assay using the high performance liquid chromatography method was carried out on four blood samples from each patient. Sample 1 was taken pre-operatively from the radial artery. Intra-operatively following lung mobilization and prior to excision, sample 2 was taken from the draining pulmonary vein and at the same time, sample 3 from the radial artery. Postoperatively, the next morning, sample 4 was taken from the radial artery. RESULTS: The mean values for serum heparin levels in pg/ml of samples 1-4 were found to be 205.1 (SD+/-282.1), 366.0 (SD+/-371.7), 337.2 (SD+/-225.3) and 250.8 (SD+/-282.2), respectively. These results show that intraoperative serum heparin levels (samples 2 and 3) are significantly higher (P = 0.0016, P = 0.0014, respectively) than pre-operative values (sample 1). The difference between sample 2 (pulmonary) and sample 3 (systemic circulation) was not significant (P = 0.6508). Although postoperative heparin levels (sample 4) were found to be higher than pre-operative values, yet it was not statistically significant (P = 0.1340). The mean of pre-operative heparin levels in patients with lung carcinoma and inflammatory diseases were 136.2 (SD+/-62.6) and 259.4 (SD+/-368.3), respectively. Intra-operatively, heparin levels increased to 260.9 (SD+/-139.7) and 449 (SD+/-470.7), respectively. These results suggest that the mean heparin level for patients with inflammatory lung diseases was higher than that for carcinoma patients. CONCLUSIONS: Within the context of lung surgery for carcinoma or inflammatory diseases, it appears that operative trauma enhances heparin release into both the pulmonary and systemic circulations, possibly through pulmonary mast cell degranulation. Thus, an episodic auto anti-coagulant effect is established during the course of surgery. Such findings may partly provide an understanding of the excessive bleeding encountered during some thoracotomies and the recognized reduced incidence of thrombo-embolic complications among thoracic surgical patients. Should an unexplained bleeding occur during the course of surgery, an excess of heparin release is recommended to be kept in mind as a possible cause.

Pericardial Tamponade: A Manifestation of Pericardial Sac Sarcoma-A Case Report.

Cardiac tamponade was manifested in a 30-year-old male with a 6-month history of fever and weight loss prior to admission. Cross-sectional echocardiography demonstrated huge pericardial effusion with a large mass in the posterior pericardial space. Pericardiocentesis revealed exudative fluid with no malignant cells. Surgery performed to determine the nature of the mass disclosed the mass originating from the posterior pericardium, invading the posterior pleural sac and adjacent structures. Histopathology identified spindle cell sarcoma. The preoperative diagnosis of the mass and its presenting features and nature are discussed. (ECHOCARDIOGRAPHY, Volume 13, May 1996)

Timing of revascularization after acute myocardial infarction.

The optimal timing of surgical revascularization after acute myocardial infarction remains controversial. Higher mortality after emergency coronary artery bypass has been documented. We retrospectively reviewed 278 patients who underwent coronary artery bypass between 2005 and 2007. The time from onset of myocardial infarction to surgical revascularization was the basis for dividing patients into 3 groups: surgery was performed within 24 h in group 1, at 24-72 h in group 2, and after 14 days in group 3. There was a definite relationship between the timing of revascularization and the outcome of surgery. Group 1 had a mortality rate of 11.7%, group 2 had 7% mortality, and group 3 had 2.5% mortality. Group 1 had the highest incidence of postoperative complications. Surgical revascularization within 24 h of acute myocardial infarction was associated with significantly higher risks of mortality and morbidity than procedures performed after 72 h.