Impedance cardiography revisited.

UNLABELLED: Previously reported comparisons between cardiac output (CO) results in patients with cardiac conditions measured by thoracic impedance cardiography (TIC) versus thermodilution (TD) reveal upper and lower limits of agreement with two standard deviations (2SD) of approximately +/-2.2 l min(-1), a 44% disparity between the two technologies. We show here that if the electrodes are placed on one wrist and on a contralateral ankle instead of on the chest, a configuration designated as regional impedance cardiography (RIC), the 2SD limit of agreement between RIC and TD is +/-1.0 l min(-1), approximately 20% disparity between the two methods. To compare the performances of the TIC and RIC algorithms, the raw data of peripheral impedance changes yielded by RIC in 43 cardiac patients were used here for software processing and calculating the CO with the TIC algorithm. The 2SD between the TIC and TD was +/-1.7 l min(-1), and after annexing the correcting factors of the RIC formula to the TIC formula, the disparity between TIC and TD further declined to +/-1.25 l min(-1). CONCLUSIONS: (1) in cardiac conditions, the RIC technology is twice as accurate as TIC; (2) the advantage of RIC is the use of peripheral rather than thoracic impedance signals, supported by correcting factors.

L-NMMA (a nitric oxide synthase inhibitor) is effective in the treatment of cardiogenic shock.

BACKGROUND: The objective was to assess the safety and efficacy of L-NMMA in the treatment of cardiogenic shock. METHODS: We enrolled 11 consecutive patients with cardiogenic shock that persisted after >24 hours from admission, despite coronary catheterization and primary percutaneous transluminal coronary revascularization, when feasible, and treatment with mechanical ventilation, intraaortic balloon pump (IABP), and high doses of catecholamines. L-NMMA was administered as an IV bolus of 1 mg/kg and continuous drip of 1 mg. kg(-1). h(-1) for 5 hours. Treatment with catecholamines, mechanical ventilation, and IABP was kept constant throughout the study. RESULTS: Within 10 minutes of L-NMMA administration, mean arterial blood pressure (MAP) increased from 76+/-9 to 109+/-22 mm Hg (+43%). Urine output increased within 5 hours from 63+/-25 to 156+/-63 cc/h (+148%). Cardiac index decreased during the steep increase in MAP from 2. 0+/-0.5 to 1.7+/-0.4 L/(min. m(2)) (-15%); however, it gradually increased to 1.85+/-0.4 L/(min. m(2)) after 5 hours. The heart rate and the wedge pressure remained stable. Twenty-four hours after L-NMMA discontinuation, MAP (+36%) and urine output (+189%) remained increased; however, cardiac index returned to pretreatment level. No adverse events were detected. Ten out of eleven patients could be weaned off mechanical ventilation and IABP. Eight patients were discharged from the coronary intensive care unit, and seven (64%) were alive at 1-month follow-up. CONCLUSIONS: L-NMMA administration in patients with cardiogenic shock is safe and has favorable clinical and hemodynamic effects.

High-dose intravenous isosorbide-dinitrate is safer and better than Bi-PAP ventilation combined with conventional treatment for severe pulmonary edema.

OBJECTIVE: To determine the feasibility, safety and efficacy of bilevel positive airway ventilation (BiPAP) in the treatment of severe pulmonary edema compared to high dose nitrate therapy. BACKGROUND: Although noninvasive ventilation is increasingly used in the treatment of pulmonary edema, its efficacy has not been compared prospectively with newer treatment modalities. METHODS: We enrolled 40 consecutive patients with severe pulmonary edema (oxygen saturation <90% on room air prior to treatment). All patients received oxygen at a rate of 10 liter/min, intravenous (IV) furosemide 80 mg and IV morphine 3 mg. Thereafter patients were randomly allocated to receive 1) repeated boluses of IV isosorbide-dinitrate (ISDN) 4 mg every 4 min (n = 20), and 2) BiPAP ventilation and standard dose nitrate therapy (n = 20). Treatment was administered until oxygen saturation increased above 96% or systolic blood pressure decreased to below 110 mm Hg or by more than 30%. Patients whose conditions deteriorated despite therapy were intubated and mechanically ventilated. All treatment was delivered by mobile intensive care units prior to hospital arrival. RESULTS: Patients treated by BiPAP had significantly more adverse events. Two BiPAP treated patients died versus zero in the high dose ISDN group. Sixteen BiPAP treated patients (80%) required intubation and mechanical ventilation compared to four (20%) in the high dose ISDN group (p = 0.0004). Myocardial infarction (MI) occurred in 11 (55%) and 2 (10%) patients, respectively (p = 0.006). The combined primary end point (death, mechanical ventilation or MI) was observed in 17 (85%) versus 5 (25%) patients, respectively (p = 0.0003). After 1 h of treatment, oxygen saturation increased to 96 +/- 4% in the high dose ISDN group as compared to 89 +/- 7% in the BiPAP group (p = 0.017). Due to the significant deterioration observed in patients enrolled in the BiPAP arm, the study was prematurely terminated by the safety committee. CONCLUSIONS: High dose ISDN is safer and better than BiPAP ventilation combined with conventional therapy in patients with severe pulmonary edema.

Increased toxicity of high-dose furosemide versus low-dose dopamine in the treatment of refractory congestive heart failure.

OBJECTIVE: To evaluate the safety and efficacy of low-dose dopamine, high-dose furosemide, and their combination in the treatment of refractory congestive heart failure. METHODS: Twenty consecutive patients with refractory congestive heart failure were randomized to receive intravenous low-dose (4 micrograms/kg/min) dopamine combined with low-dose (80 mg/day) oral furosemide (group A; n = 7), intravenous low-dose dopamine with medium-dose furosemide (5 mg/kg/day through continuous intravenous administration; group B; n = 7), or high-dose furosemide (10 mg/kg/day through continuous intravenous administration; group C; n = 6). RESULTS: The three groups showed similar improvement in signs and symptoms of congestive heart failure, urinary output (2506 +/- 671 ml/24 hr, mean +/- SD) and weight loss (3.3 +/- 2.3 kg) after 72 hours of therapy. Mean arterial blood pressure (MAP) decreased by 14% +/- 8% and 15% +/- 6% in groups B and C, respectively, but increased by 4% +/- 15% in group A (p = 0.017). Renal function deteriorated significantly in groups B and C: creatinine clearance decreased by 41% +/- 23% and 42% +/- 23%, respectively, but increased by 14% +/- 35% in group A (p = 0.0074). MAP decrease was positively correlated with the decrease in creatinine clearance (r = 0.7; p = 0.0007). Patients in group B and C had more hypokalemia than group A. Two patients in group C sustained acute oliguric renal failure and one patient in group B died suddenly while sustaining severe hypokalemia. CONCLUSION: Combined low-dose intravenous dopamine and oral furosemide have similar efficacy but induce less renal impairment and hypokalemia than higher doses of intravenous furosemide taken either alone or with low-dose dopamine. The renal impairment induced by intravenous furosemide is probably related to its hypotensive effect in patients with refractory congestive heart failure.

Infarct site-related mortality in patients with recurrent myocardial infarction. SPRINT Study Group.

PURPOSE: The purpose of this study was to determine the effect of acute and old myocardial infarction (MI) sites on early (15 days) mortality in patients with a second MI. PATIENTS AND METHODS: Data are derived from the SPRINT 2 study population that included 1,161 consecutive patients with acute MI, aged 50 to 79 years, recruited from 14 coronary care units in Israel between November 1985 and July 1986. Two hundred twenty-six of these patients (19.5%) had a previous MI prior to the index acute MI. Sixty-two patients were excluded from the analysis either because the MI site was not of anterior or inferior location, or because of incomplete data. In the 164 (73%) remaining patients, acute and old MI locations were determined to be either anterior or inferior and were accordingly divided into 4 groups: acute anterior-old anterior (Group 1-23 patients); acute anterior-old inferior (Group 2-86 patients); acute inferior-old anterior (Group 3-34 patients); acute inferior-old inferior (Group 4-21 patients). RESULTS: Significant differences in clinical parameters among the four groups included a higher proportion of Q-wave MI (p = 0.04), severe congestive heart failure during admission (p = 0.04), and markedly elevated serum lactate dehydrogenase levels (p = 0.05) in Group 3. High-degree atrioventricular block (p = 0.001) and cardiogenic shock (p = 0.05) also developed more often in this group during hospitalization. Twenty-three patients (14%) died within 15 days. Death rates in the acute anterior (Group 1 plus Group 2) and the acute inferior (Group 3 plus Group 4) groups were 11% versus 20%, respectively (NS). However, death rate variability across the four groups was statistically significant (p = 0.018), with the highest mortality observed in Group 3 (old anterior-acute inferior MI-29%). Multivariate analysis identified acute inferior MI following old anterior MI as a strong independent predictor of early death (relative odds vis-à-vis other combinations 5.0, 95% confidence interval 1.5 to 16.6). CONCLUSION: This study identifies a subgroup of patients with acute inferior MI at high risk for early mortality. It is possible that such patients would benefit from early reperfusion therapy.

Usefulness of losartan, captopril, and furosemide in preventing nitrate tolerance and improving control of unstable angina pectoris.

Sixty consecutive normotensive patients with unstable angina pectoris, who were on continuous intravenous isosorbide dinitrate (ISDN) treatment and had not previously received angiotensin II receptor antagonists, angiotensin-converting enzyme (ACE) inhibitors, or diuretics were randomly assigned to treatment groups receiving intravenous ISDN for 72 hours. No additional treatment was given to group A (n = 15). Captopril, in a test dose of 6.25 mg, and followed by 12.5 mg 3 times daily for 24 hours and 25 mg 3 times daily for the next 24 hours, was given to group B (n = 15). The same dose of captopril plus 40 mg of furosemide in the morning were given to group C (n = 15). Losartan, in a single dose of 25 mg/day and increased to 50 mg after 24 hours was given to group D (n = 15). Nitrate tolerance was evaluated at 24-hour intervals at trough levels of each of the drugs by administering intravenous ISDN (1 mg bolus dose every 4 minutes) and recording the total ISDN test dose required to decrease the mean arterial blood pressure by > or =10%. Treatment with continuous ISDN only (group A) induced nitrate tolerance. The ISDN (mean +/- SD) test dose was 3.5 +/- 1.8 mg at baseline, increasing to 4.9 +/- 2.4 mg at 24 hours, and 8.0 +/- 3.0 mg at 48 hours. The addition of increasing doses of captopril to the continuous ISDN treatment (group B) completely prevented nitrate tolerance. Losartan, however, did not attenuate nitrate tolerance at 24 hours and attenuated it only partially at 48 hours. The addition of furosemide to captopril had no further effect on nitrate tolerance. Of 15 patients in group A (ISDN only), 4 (27%) experienced recurrent ischemic events requiring urgent coronary catheterization. No such events were recorded in group B (captopril), but did occur in 1 patient in each of group C (captopril plus furosemide) and D (losartan) (p = 0.083). Thus, the addition of captopril to the ISDN treatment regimen prevented tolerance to nitrates and improved angina control with apparent safety. Losartan also decreased nitrate tolerance, although to a lesser extent, and also improved angina control. The addition of furosemide to captopril conferred no further benefit.

Coronary artery bypass without cardiopulmonary bypass: analysis of short-term and mid-term outcome in 220 patients.

Two hundred twenty patients, preferentially those with high-risk conditions, underwent coronary artery bypass grafting without cardiopulmonary bypass. Early unfavorable outcome events included operative mortality (7 patients, 3.2%), nonfatal perioperative myocardial infarction (6 patients, 2.7%), cerebrovascular accident (1 patient, 0.4%), and sternal infection (3 patients, 1.4%). There were two deaths (13%) among 15 patients with calcified aorta and four (12%) in 33 patients who underwent emergency operation. Multivariate analysis revealed these two risk factors to be the only predictors of early mortality (odds ratios, 8.0 and 9.8, respectively). Preoperative risk factors such as left ventricular dysfunction (ejection fraction < or = 35%) (40 patients, 18%), congestive heart failure (46 patients, 21%), acute myocardial infarction (59 patients, 27%), cardiogenic shock (7 patients, 3%), age 70 years or older (59 patients, 27%), renal failure (19 patients, 9%), and cerebrovascular accident and carotid disease (11 patients, 5%) were not found to be major predictors of early mortality or unfavorable outcome. During 12 months of follow-up (range 1 to 21 months), there were four cardiac and three noncardiac deaths (1-year actuarial survival 93%) and 17 cases (7.7%) of early return of angina. Calcified aorta, nonuse of the internal mammary artery, reoperation, and diabetes mellitus were independent predictors of unfavorable events. We conclude that coronary artery bypass grafting without cardiopulmonary bypass can be done with relatively low operative mortality, although there seems to be an increased risk for early return of angina. This procedure should therefore be considered for patients with appropriate coronary anatomy, in whom cardiopulmonary bypass poses a high risk. This procedure is still hazardous with calcified aorta or emergency operation.

Histologic abnormalities of the ascending aorta and pulmonary trunk in patients with bicuspid aortic valve disease: clinical relevance to the ross procedure.

OBJECTIVE: Bicuspid aortic valve disease is often associated with dilation of the aortic root and ascending aorta. This study examines the histologic features of the ascending aorta and main pulmonary artery of patients with and without aortic valve disease. METHODS: Samples from ascending aorta and main pulmonary artery were obtained at the time of the operation from 20 patients with bicuspid aortic valve and 11 patients with tricuspid aortic valve disease. In addition, samples were also obtained from autopsy cases with normal aortic valve. The histologic changes were graded from 1 to 3 according to severity of degenerative changes. RESULTS: In the ascending aorta, the severity of cystic medial necrosis (P =.001), elastic fragmentation (P =.002), and changes in the smooth muscle cell orientation (P =.002) were significantly more severe in patients with bicuspid than in those with tricuspid aortic valve disease. In the pulmonary trunk specimens, those 3 histologic features were also significantly more severe in patients with bicuspid than those with tricuspid valves (P =.001, P =.01, and P =.04, respectively). Seventy-five percent of patients with bicuspid aortic valve disease had grade 3 degenerative changes, whereas only 14% of those patients with tricuspid aortic valve disease had similar degrees of degenerative changes. CONCLUSION: Patients with bicuspid aortic valve disease have more severe degenerative changes in the media of the ascending aorta and main pulmonary artery than patients with tricuspid aortic valve disease. These findings may explain root and ascending aortic dilation in patients with bicuspid aortic valve disease and pulmonary autograft dilation in certain patients after the Ross procedure.

Reoperative coronary artery bypass without cardiopulmonary bypass.

BACKGROUND: Conventional reoperative coronary artery bypass grafting using cardiopulmonary bypass carries relatively high mortality and morbidity. METHODS: Seventy-seven patients underwent coronary artery bypass grafting without cardiopulmonary bypass in two centers between 1988 and 1994. Mean age was 65 +/- 8 years (mean +/- SD). Twenty-three (30%) were operated on urgently and 7 (9%) emergently. Nine (12%) were referred for operation up to 2 weeks after acute myocardial infarction. Fifteen patients (19%) had an ejection fraction less than or equal to 0.35. The mean number of grafts per patient was 1.7 (range, 1 to 3), and the internal mammary artery was used in 66 patients (86%). Only 18 patients (23%) received at least one graft to the circumflex artery. Hospital stay was 7.4 +/- 6.5 days. RESULTS: Early events included operative death in 4 patients (5.2%), nonfatal myocardial infarction in 3 (3.9%), sternal infection in 2 (2.6%), and stroke in 0 (0%). Follow-up (30 +/- 15 months) showed 11 deaths (5 cardiac, 6 noncardiac), 2 (2.8%) nonfatal myocardial infarctions, and return of angina in 9 patients (12.8%). One- and 4-year actuarial survival rates were 90% and 69%, respectively. CONCLUSIONS: Reoperative coronary artery bypass grafting without cardiopulmonary bypass has acceptable early and midterm outcome, and should be considered a viable alternative for properly selected patients.

Primary coronary artery bypass grafting without cardiopulmonary bypass in impaired left ventricular function.

BACKGROUND: Conventional coronary artery bypass grafting using cardiopulmonary bypass carries relatively high mortality and morbidity for patients with left ventricular dysfunction. METHODS: Seventy-five patients with ejection fraction less than or equal to 0.35 underwent primary coronary artery bypass grafting without cardiopulmonary bypass between December 1991 and December 1994. Thirty-two patients (43%) had congestive heart failure, 11 (15%) were referred for operation within the first 24 hours of evolving myocardial infarction, and 21 (28%) up to 1 week after acute myocardial infarction. Eighteen patients (24%), 6 of whom were in cardiogenic shock, underwent emergency operations. RESULTS: Mean number of grafts/patient was 1.9 (range, 1 to 4), and internal mammary artery was used in 66 patients (85%). Only 17 patients (23%) received a graft to a circumflex marginal artery. Two patients (2.7%) died perioperatively, and 1 (1.3%) sustained stroke. At mean follow-up of 28 months, 13 patients had died, and angina had returned in 7 (10.5%). One- and four-year actuarial survival was 96% and 73%, respectively. CONCLUSIONS: Coronary artery bypass grafting without cardiopulmonary bypass is a viable alternative to conventional coronary artery bypass grafting particularly for patients with extreme left ventricular dysfunction or those with coexisting risk factors, such as acute myocardial infarction and cardiogenic shock.

Fresh blood units contain large potent platelets that improve hemostasis after open heart operations.

Twenty units of fresh whole blood were separated into fresh packed red blood cells (PC) and platelet-rich plasma (PRP) and were transfused to 40 patients immediately after coronary bypass grafting. Patients were preoperatively randomized to receive either PRP (group A, 20 patients) or PC (group B, 20 patients). Platelet number in the PRP group was greater, but not significantly greater, than in the PC group (7.5 +/- 3 versus 5.9 +/- 2.2 x 10(10); p = not significant). However, mean platelet volume in the PC group was significantly greater (8.75 +/- 1.1 versus 6 +/- 0.7 fL). Postoperatively, group A patients bled more than group B (566 +/- 164 versus 327 +/- 41 mL; p less than 0.01) and received more red blood cell units (2.7 +/- 1.2 versus 1.6 +/- 0.7 U; p less than 0.05) and a larger number of blood products (5.9 +/- 3.7 versus 2.6 +/- 1.2 U; p less than 0.05). Transfusion of PRP to group A increased platelet count from 128 +/- 20 to 148 +/- 110 x 10(9)/L; however, platelet functions did not improve. Administration of PC to group B increased platelet count from 139 +/- 22 to 156 +/- 23 x 10(9)/L, improved platelet aggregation (with collagen from 33% +/- 20% to 53% +/- 23%, with epinephrine from 36% +/- 24% to 51% +/- 20%; p less than 0.05), and corrected the prolonged bleeding time. The results suggest that the improved hemostasis observed after fresh whole blood administration is related to the large, potent platelets that remained in the PC and were not separated to the PRP during standard platelet concentrate preparation.

Circulatory arrest under moderate systemic hypothermia and cold retrograde cerebral perfusion.

BACKGROUND: Profound hypothermia is used for circulatory arrest during cardiovascular operations. Cold retrograde cerebral perfusion enhances cerebral protection during circulatory arrest. This study examines the results of circulatory arrest under moderate systemic hypothermia and cold retrograde cerebral perfusion. METHODS: Circulatory arrest under moderate systemic hypothermia (nasopharyngeal temperatures of 19 degrees to 28 degrees C, mean of 23 degrees C) and cold (10 degrees C) retrograde cerebral perfusion were employed in 104 consecutive patients for operation on the proximal aorta (103 patients) or for a venous tumor invading the heart (1 patient). Aortic operations consisted of replacement of the entire transverse arch in 49 patients, hemiarch in 16, ascending aorta in 37, and an extraanatomic aortic bypass in 1. Most patients (83%) also had other procedures such as coronary artery bypass or an aortic valve operation. Sixteen patients had had previous aortic operations. The mean circulatory arrest time was 27 minutes (range, 6 to 105 minutes). RESULTS: There were eight in-hospital deaths. Preoperative shock, peripheral vascular disease, and previous aortic operations were independent predictors of operative mortality. There were eight strokes; clinical assessment and computed tomographic scans of the brain suggested that the strokes were embolic in 6 patients. Atherosclerosis/laminated thrombi in the aorta and the duration of circulatory arrest were independent predictors of stroke. Four patients had seizures without neurologic deficit. No patient had development of paraplegia or paraparesis. CONCLUSIONS: Systemic hypothermia of 23 degrees C (nasopharyngeal) and cold retrograde cerebral perfusion (10 degrees C) appear to be safe for circulatory arrest times of less than 30 minutes. This strategy of cerebral protection may also be adequate for longer circulatory arrest times.

Routine use of bilateral skeletonized internal mammary arteries for myocardial revascularization.

BACKGROUND: Complete arterial myocardial revascularization without the use of saphenous veins grafts was primarily performed on selected patient populations such as the young and nondiabetic. In a recently developed surgical technique, the internal mammary artery is dissected gently as a longer skeletonized artery, providing greater versatility for complete arterial revascularization, without saphenous veins grafts. METHODS: We prospectively evaluated the impact of the routine use of double skeletonized internal mammary artery in 472 patients who underwent coronary artery bypass grafting between April 1996 and June 1997. Their average age was 65 years (30 to 87 years), 383 (83%) were men, and 89 (17%) women. One hundred sixty-nine (36%) of the patients were older than 70 years, and 145 (31%) were diabetic. The average number of grafts was 3.2 per patient (two to six grafts). RESULTS: Operative mortality was 1.7% (n = 8). The mortality of urgent and elective patients was 0.7% (3 of 410 patients), and that of emergency operations was 8.1% (5 of 62 patients; p < 0.01). There were three (0.6%) perioperative infarcts, and 6 patients (1.3%) sustained strokes. Sternal wound infection occurred in 8 patients (1.7%). Postoperative follow-up (1 to 25 months) was available in 462 patients (99%). Two-year actuarial survival was 96.8%, and 92% of the surviving patients are well and free of angina. Neither diabetes mellitus nor old age (>70 years) were significant independent predictors of any early or late untoward events. None of the 70 diabetic patients more than 65 years of age developed sternal wound infection. Chronic lung disease was found to be the only independent predictor for sternal infections. CONCLUSIONS: Routine use of bilateral skeletonized internal mammary artery is a safe replacement for the current myocardial revascularization technique even in the old and diabetic patients.

Comparison of myocardial revascularization without cardiopulmonary bypass to standard open heart technique in patients with left ventricular dysfunction.

OBJECTIVE: To compare myocardial revascularization without cardiopulmonary bypass to standard open heart technique in patients with left ventricular (LV) dysfunction. METHODS: 117 patients with LV dysfunction (ejection fraction (EF) < 35%) underwent coronary artery bypass surgery between January 1991 and July 1994. Sixty-four (group A) were operated on without a cardiopulmonary bypass, and 53 (group B) with one. Prevalence of EF < 20% (17 vs. 6%) and emergency operations (22 vs. 7%, P = 0.03) was higher in group A. The average number of grafts was 1.9 +/- 0.8/pt in group A and 3.5 +/- 0.9/pt in group B (P < 0.01), and the internal mammary artery was used in 54 (84%) and 42 (79%) patients, respectively. Only 16 patients (25%) in group A received a graft to a circumflex marginal artery compared to 51 (96%) in group B (P < 0.0001). RESULTS: Two patients (3.1%) died perioperatively in group A compared to 7 (13%) in group B (P = NS). In two patients from group A (3.1%) and in four (7.5%) from group B intra-aortic balloon pump was inserted postoperatively (P = NS). One year actuarial survival was 91 and 79% (P = 0.03) and 2-year survival was 86 and 65% (P = 0.04), respectively. Return of angina occurred in five (8%) and three (6%) patients (P = NS). CONCLUSIONS: These results show a trend for lower operative risk resulting in better overall survival in selected patients with LV dysfunction undergoing coronary artery bypass surgery without cardiopulmonary bypass.

Predictors of early and overall outcome in coronary artery bypass without cardiopulmonary bypass.

OBJECTIVE: Cardiopulmonary bypass in coronary artery bypass graft operations may adversely affect the outcome especially in high-risk patients. The purpose of this study is to evaluate results of coronary artery bypass performed without cardiopulmonary bypass, in a relatively high-risk cohort, and to identify predictors of unfavorable outcome. METHOD: Three hundred and thirteen (313) patients, 246 (79%) of whom had high-risk conditions, who have a coronary anatomy suitable for coronary artery bypass surgery without cardiopulmonary bypass, underwent this procedure between December 1991 and July 1995. Mean number of grafts/patient was 1.8 (1-5), and only 71 patients (23%) received a graft to the circumflex coronary system. RESULTS: Early unfavorable outcome events included operative mortality (12 patients, 3.8%), nonfatal perioperative myocardial infarction (eight patients, 2.6%), emergency reoperation (three patients, 0.9%), sternal infection (five patients, 1.6%), and nonfatal stroke (two patients, 0.6%). Multivariate analysis revealed angina pectoris class IV (odds ratio 5.4) and age > or = 70 years (odds ratio 5.0) as independent predictors of early mortality. Preoperative risk factors such as repeat coronary artery bypass grafting (50 patients, 16%), ejection fraction < or = 0.35 (85 patients, 27%), acute myocardial infarction (86 patients, 28%), cardiogenic shock (ten patients, 3.2%), chronic renal failure (25 patients, 8%), chronic obstructive pulmonary disease (20 patients, 6%), and peripheral vascular disease (51 patients, 16%) did not increase early mortality. During 33 months of follow-up (range 1-57 months), there were 42 deaths, at least 16 cardiac-related (one and four years actuarial survival of 90% and 76% respectively), and 39 patients (12.5%) in whom angina returned. Calcified aorta (odds ratio 2.6) and old myocardial infarction (odds ratio 1.8) were independent predictors of overall unfavorable events. CONCLUSIONS: Coronary artery bypass grafting without cardiopulmonary bypass can be performed with relatively low operative mortality in certain high-risk subgroups of patients; however, an increased risk of graft occlusion is a potential disadvantage. This procedure should therefore be considered only for patients with suitable coronary anatomy, in whom cardiopulmonary bypass poses a high risk. Although the risk of stroke is relatively low, the procedure is still hazardous for patients aged 70 years and over.

Arterial embolization in the treatment of Curling's ulcer bleeding in a burn patient.

Curling's ulcer bleeding is a well-known life-threatening complication of the severely thermally injured patient. This report describes a successful left gastric artery embolization in a 70 per cent total body area burn patient with severe gastric bleeding. We discuss the various non-surgical invasive modalities for treating such patients, and emphasize the advantages of arterial embolization over surgery.

Coronary by-pass reoperations without cardiopulmonary by-pass: the Israeli experience.

OBJECTIVES: To evaluate results of coronary artery by-pass grafting (CABG) reoperations without cardiopulmonary by-pass (CPB). MATERIALS AND METHODS: Thirty-two patients underwent CABG reoperation with CPB between December 1991 and December 1993. There were 29 (91%) males, and 3 (9%) females. Mean age was 62 +/- 7 years. Five (16%) were operated on emergently, two (6%) of them during cardiogenic shock. Three (9%) were referred for operation up to two weeks following acute MI. Six (19%) had preoperative EF < 35%. Significant associated systemic diseases included previous CVA in two patients (6%), calcified aorta in two (6%), peripheral vascular disease in six (19%), renal failure in one (3%), and severe COPD in one (3%). Mean number of grafts/pt was 1.5 (range 1-3), and IMA was used in 26 (81%) of patients. Only nine patients (28%) received a graft to a circumflex marginal artery, six (66%) of whom were operated on through left thoracotomy. RESULTS: Only two patients (6%) had low output syndrome postoperatively; one was supported with catecholamines, and the other with intraaortic balloon pump. Hospital stay was 6.1 +/- 1.5 days (mean +/- SD). Early unfavorable outcome included operative death in one patient (3.1%), non-fatal MI in two (6%), and sternal infection in one (3%). Follow-up (10 +/- 5 months, mean +/- SD) showed two late deaths (one cardiac, and one carcinoma), one (3%) non-fatal MI, and return of angina in three (9%) patients. CONCLUSIONS: CABG reoperations without CPB should be considered, particularly for revascularization of the LAD and RCA systems. Left thoracotomy is optional for patients with disease confined to circumflex and LAD systems.

Coronary artery by-pass without cardiopulmonary by-pass for patients with severe left ventricular dysfunction.

OBJECTIVES: To evaluate results of coronary artery bypass grafting (CABG) without cardiopulmonary by-pass (CPB) for patients with severe left ventricular dysfunction. MATERIALS AND METHODS: Fifty-three patients with severe LV dysfunction (EF < 35%) underwent CABG without cardiopulmonary by-pass (CPB) between December 1991 and December 1993. They comprise 22% of 242 patients operated on without CPB by one of the authors (RM) in this period. There were 45 (85%) males and eight (15%) females. Twelve (23%) patients were over 70 years. Nine (17%) were re-do CABG. Ten (19%) were referred for operation within the first 24 hours of evolving MI, and 13 (25%) up to two weeks after acute MI. Nine (17%) had preoperative EF < 20%, and six patients (11%) were in cardiogenic shock. Mean number of grafts/pt was 1.8 and IMA was used in 41 (77%). Only 14 patients (26%) received a graft to a circumflex marginal artery. Ischemic time was 8 +/- 4 min/graft (mean +/- SD) when anastomosed to the LAD or RCA, and 14 +/- 7 min/graft when anastomosed to a marginal branch. RESULTS: One patient (1.9%) died perioperatively, and two (3.7%) suffered a non-fatal MI. At two-year follow-up there were three late deaths, one of them from cancer. Three patients had return of angina, two of them were reoperated upon. CONCLUSIONS: These results suggest that CABG without CPB may be advantageous for patients with severe LV dysfunction.

[Coronary artery bypass without extra corporeal circulation].

240 patients underwent coronary artery bypass grafting (CABG) without extracorporeal circulation (ECC). Mean grafts per patient was 1.9 (range 1-5). The internal mammary artery (IMA) was used in 210 cases (87%), but in only 53 (22%) were there grafts to the circumflex marginals. Unfavorable results included an operative mortality of 7 cases (2.9%), nonfatal perioperative myocardial infarction (MI) (2.5%), stroke (0.4%), and sternal infection (1.7%). There were 2 deaths among 17 patients (12%) with calcified aorta, and 4 among 40 (10%) who underwent emergency operation. Multivariate analysis showed these 2 risk factors to be the only predictors of early mortality: emergency operation odds ratio 9.8, and calcified aorta odds ratio 8.0. Perioperative risk factors that were not major predictors of early mortality or unfavorable outcome included left ventricular dysfunction (EF < 35%: 52 patients, 22%), congestive heart failure (53, 22%), cardiogenic shock (8, 3%), acute MI (67, 28%), age > 70 years (64, 27%), renal failure (22, 9%), and stroke or carotid disease (12, 5%). Followup ranged from 1-31 months (mean 12). There were 9 late deaths (4 cardiac), and 18 cases (7.5%) of early return of angina. 1-year actuarial survival was 92%; 192 patients (80%) had uneventful outcomes and are doing well. Calcified aorta, nonuse of the IMA, reoperation, and diabetes mellitus were independent predictors of unfavorable events. We conclude that CABG without ECC can be performed with relatively low operative mortality, but there seems to be increased risk of early return of angina. It should therefore be considered for those patients with appropriate coronary anatomy in whom ECC poses a very high risk. However, it is still a hazardous procedure when used as as an emergency operation, and for cases with calcified aorta.