Predicting long-term functional results after myocardial revascularization in ischemic cardiomyopathy

OBJECTIVE: The goal of the present study was to define the early and late functional results after revascularization in ischemic cardiomyopathy and to identify variables predictive of a favorable outcome. METHODS: A retrospective review of all consecutive patients with ischemic cardiomyopathy undergoing myocardial revascularization between January 1991 and June 1998 was undertaken. One hundred sixty-seven patients (140 men) aged 60 +/- 8 years (range, 39-77 years) with angina (n = 107), congestive heart failure (n = 54), or silent ischemia (n = 6) were identified. One hundred six (63%) patients with angina were in Canadian Cardiovascular Society class III or IV, and 40 (24%) patients with congestive failure were in New York Heart Association class III or IV. The preoperative left ventricular ejection fraction averaged 0.28 +/- 0.05 (range, 0.16-0. 30). Thirteen (8%) patients required preoperative mechanical life support. A mean of 2.9 +/- 0.9 grafts per patient were performed, with an average myocardial ischemia time of 53 +/- 23 minutes and bypass time of 104 +/- 31 minutes. RESULTS: There were 3 (1.7%) early deaths and 21 (13%) deaths during follow-up (2.7 +/- 2.1 years; range, 0.3-7.8 years), producing a survival of 94% +/- 2% and 75% +/- 10% at 1 and 5 years, respectively. Despite a significant increase in left ventricular ejection fraction (0.28 +/- 0.05 vs 0. 38 +/- 0.09, P =.0001), only 89 (54%) patients were symptom-free at follow-up. Freedom from recurrent angina was 98% +/- 1% and 81% +/- 8%, whereas freedom from congestive failure was 78% +/- 11% and 47% +/- 20% at 1 and 5 years, respectively. Follow-up New York Heart Association class in patients with congestive failure was improved (40/54 class III-IV vs 11/54 class III-IV, P =.0001). Multivariate analysis showed a lower ejection fraction (P =.01), preoperative congestive failure (P =.03), and a need for preoperative intra-aortic balloon pumping (P =.03) to be associated with a greater prevalence of recurrent congestive failure, whereas male sex (P =.01), preoperative angina (P =.04), use of the internal thoracic artery (P =.03), and higher number of grafts (P =.01) were associated with lower prevalence. Male sex (P =.06), higher number of grafts (P =.04), and shorter duration of myocardial ischemia (P =. 04) were also predictive of improvement in New York Heart Association class at follow-up. CONCLUSIONS: Despite satisfactory early and late survival, late functional outcome after myocardial revascularization in ischemic cardiomyopathy remains suboptimal because of recurrence or persistence of congestive failure. Selection of appropriate surgical candidates and extensive use of complete revascularization with the internal thoracic artery may substantially improve functional results.     

Reverse-remodeling after coronary artery bypass grafting in ischemic cardiomyopathy: assessment of myocardial viability by delayed-enhanced magnetic resonance imaging can help cardiac surgeons

Preoperative delayed-enhanced magnetic resonance imaging (DE-MRI) was performed to estimate myocardial viability in a 57-year-old man with ischemic cardiomyopathy in order to decide the best course of treatment. The patient was diagnosed as having congestive heart failure with triple-vessel involvement (ejection fraction of 7%, end-diastolic volume index of 160 ml/m2, end-systolic volume index of 148 ml/m2). 99mTc-sestamibi single-photon emission computed tomography revealed severe reduction of the uptake at both stress and resting phases in the anterior, lateral and inferior segments. However, DE-MRI demonstrated transmural hyperenhancement to be <25% within the whole ventricular wall, implying that, though there was extensive subendoventricular myocardial infarction, there was substantial viable myocardium. Therefore, with the expectation that functional recovery was possible with coronary revascularization alone, we performed a complete revascularization with off-pump coronary artery bypass grafting. Six months after the operation, catheterization demonstrated dramatic improvement in ventricular function, with the ejection fraction having increased to 36%. This case suggests that preoperative assessment of myocardial viability by DE-MRI could help cardiac surgeons to choose the best treatment for patients with ischemic cardiomyopathy.     

Survival after myocardial revascularization for ischemic cardiomyopathy: a prospective ten-year follow-up study

OBJECTIVE: The aim was to prospectively analyze all-cause mortality, predictors of survival, and late functional results after myocardial revascularization for ischemic cardiomyopathy over a 10-year follow-up. METHODS: We prospectively studied 57 patients with stable coronary artery disease and poor left ventricular ejection function (<35%), enrolled between 1989 and 1994. Stress thallium was analyzed in 37 patients to identify reversible ischemia. To avoid patients with a stunned myocardium, we excluded those with unstable angina or myocardial infarction within the previous 4 weeks. Mean age of the patients was 67 +/- 8 years, and 93% of patients were men. Mean left ventricular ejection fraction was 0.28 +/- 0.04, 50% were in Canadian Cardiovascular Society angina class III-IV, and 65% were in New York Heart Association functional class III-IV. RESULTS: Operative mortality was 1.7% (1/57). The mean left ventricular ejection fraction (0.30) at 15 months postoperatively did not change from before operation (0.28, P =.09). There were 8 deaths at 1 year and 42 deaths over the course of the study, producing a survival of 82.5% at 1 year, 55.7% at 5 years, and 23.9% at 10 years (95% confidence interval: 14.6%-39.1%). Symptom-free survival was 77.2% at 1 year and 20.3% at 10 years. The leading cause of death was heart failure in 29% (12/42). Multivariate analysis showed that large reversible defects on stress thallium were associated with improved left ventricular ejection fraction at 1 year (P =.01) but only male sex was associated with improved long-term survival (P =.036). CONCLUSIONS: Myocardial revascularization for ischemic cardiomyopathy is associated with good functional relief from the symptoms of angina initially and, to a lesser extent, heart failure. Revascularization may have the advantage of preserving the remaining left ventricular function. However, the long-term mortality remains high.     

Immediate results of reconstructive surgery in end-stage dilated cardiomyopathy

First experiences with multistage surgical reconstruction of the left ventricle, heart valves and coronary arteries in patients with the end stage dilated cardiomyopathy are summarized. During the last three years operations have been made on 21 patients aged from 24 to 63, eight patients having idiopathic cardiomyopathy and 13 ischemic cardiomyopathy. They had markedly disturbed hemodynamics, ejection fraction of the left ventricle less than 30% and its diastolic diameter more than 70 mm. Most of the patients were candidates for heart transplantation. The Batista and Dor operations were made in combination with plastic operations on the mitral and tricuspid valves. In patients with ischemic heart disease myocardial revascularization was also performed. Four patients died after operation from arrhythmia and heart failure, the others' state had improved with less sizes of the heart and 10-12% greater ejection fraction. A conclusion was made that such operations were expedient.     

Advanced cardiac failure. New surgical approaches

THERAPEUTIC OPTIONS: Prognosis of advanced heart failure is ominous since survival rate is less than 65% one year after an acute and severe cardiac episode. Medical therapy has proven to be efficient in reducing fatal complications and in delaying critical evolution. Depending on the etiology and the myocardial status, new surgical approaches can also be proposed for repair or substitution. SURGICAL REPAIR: The beneficial effect of myocardial revascularization on severe ischemic cardiomyopathy, the relevance of mitral valve repair in dilated cardiomyopathy, and the advantage of ventricular remodeling in patients with major ventricular dyskinesia has been clearly demonstrated. All these surgical techniques improve ventricular function and enhance survival rate by about 70% after three years. SUBSTITUTION PROCEDURES: The best therapeutic option to recover heart function for normal life and reduced mortality remains, when possible, cardiac transplantation. Ventricular cardiac assist devices are planned as a temporary option to bridge the waiting period to transplantation or for myocardial recovery but can also be proposed as a chronic implantation in an outpatient care scheme. Cardiomyoplasty for therapeutic management of advanced cardiac failure is still a controversial surgical approach. Other clinical strategies such as transmyocardial laser revascularization, myocardial angiogenesis and myocardial cell therapy are being investigated or developed. ADAPTED TREATMENT: Optimal management of each patient with advanced heart failure requires an adequate treatment selected among a wide range of medical and/or surgical strategies.     

Long-term results of autologous stem cell transplantation in the treatment of patients with congestive heart failure

Background

The aim of this study was to assess the long-term efficacy of stem cell transplantation with revascularization for patients with ischemic cardiomyopathy.

Methods

We enrolled 17 patients with ischemic cardiomyopathy who had undergone autologous stem cell treatment. To assess myocardial ischemia and viability they underwent coronary angiography, stress tests with dobutamine, echocardiography, and positron emission tomography. Peripheral stem cells mobilized using granulocyte colony-stimulating factor (G-CSF) were collected by aphseresis for transplantation transmyocardially into the areas of injury during coronary artery bypass surgery to increase blood flow to the engrafted areas.

Results

Three patients died in the early follow-up period and 4 patients with cardiac failure died during mid-term follow-up; they all underwent stem cell transplantation at 6 months after acute myocardial infarction. The mean follow-up period of the remaining 10 patients was 85.8 ± 9.2 months (range, 70-100). Mean left ventricular ejection fraction improved to 30.0 ± 6.7, whereas the preoperative mean left ventricular ejection fraction of the surviving patients was 25.6 ± 4.5 (P = .035). Mean New York Heart Association (NYHA) functional class decreased from 3.2 to 1.5 (P = .006). When the study population was divided into 2 subgroups according to the interval between acute myocardial infraction and surgery, the patients who underwent autologous stem cell transplantation within the first 6 months after myocardial infraction (Group 1) showed significantly lower NYHA scores at the last follow-up (P = .024 in Group 1 and P = .102 in Group 2). No side effects were observed to be due to the stem cell or G-CSF injections.

Conclusion

Treatment of ischemic cardiomyopathy with autologous stem cell transplantation is easy and safe, opening a new window in the treatment of “no hope” patients.     

Myocardial Revascularization in Patients With Ischemic Cardiomyopathy: Functional Observations

Objective. A prospective angiographic study was undertaken to investigate, with an objective analysis, the global and regional wall response to myocardial revascularization.

Methods. Thirty-one patients (30 men and 1 woman, mean age, 61 years) with a left ventricular ejection fraction of less than 0.30 were admitted to our institution between 1992 and 1995 for two- or three-vessel coronary artery disease requiring myocardial revascularization. All patients underwent isolated coronary artery bypass grafting and were studied 3 months later with angiography. Preoperative and postoperative wall motion were analyzed using special software that computed a segmental left ventricular ejection fraction, generating a segmental score. Computerized analysis allowed us to distinguish patients with diffuse hypokinesis and a symmetric contraction pattern from patients with akinesis involving at least two segments and an asymmetric contraction pattern.

Results. There were no operative deaths and no patient required intraaortic balloon counterpulsation. One patient had postoperative enzymatic evidence of myocardial infarction. Postoperative angiography showed a graft patency rate of 84%. Global analysis showed a small but significant rise in the left ventricular ejection fraction (0.25 ± 0.51 to 0.31 ± 0.70, p < 0.001) and a fall in the left ventricular end-diastolic pressure (23.7 ± 10 to 16.5 ± 9 mm Hg, p < 0.01). Mean scores always have been lower after the operation than before it, with the best results obtained for the apex and the worst for the anterobasal segment. The group with a symmetric contraction pattern showed a trend toward a better hemodynamic response than the group with an asymmetric contraction pattern. Regression analysis revealed two important predictors of segmental functional improvement: (1) the absence of an echocardiographic scar, and (2) the presence of a collateral circulation.

Conclusions. Coronary artery bypass grafting produced a small but substantial improvement in patients with ischemic cardiomyopathy. The greater benefit occurred in patients with a symmetric contraction pattern. The absence of an echocardiographic scar and the presence of a collateral circulation predicted segmental functional improvement.     

Left ventricular aneurysm repair with myocardial revascularization: an analysis of 246 consecutive patients over 15 years

From 1970 to 1985, 246 consecutive patients with left ventricular (LV) aneurysm underwent repair and concomitant myocardial revascularization at Ochsner Foundation Hospital. The overall incidence of perioperative death was 7.3%. Although the deaths were mainly cardiac related (10/18) with congestive heart failure (CHF) as the leading cause (6/10), 8 deaths were of noncardiac origin. Perioperative mortality increased significantly in patients with mitral regurgitation (MR) (22%; p = 0.0008); perioperative mortality for patients without MR was 4.8%. The overall 5-year survival was 69%. Late deaths were caused most commonly by myocardial infarction (20/32) with only 7 due to CHF. Predictors of long-term survival were related to LV function preoperatively: absence of CHF (p = 0.001); LV end-diastolic pressure less than or equal to 20 mm Hg (p = 0.03); and ejection fraction greater than or equal to 35% (p = 0.02). Factors that did not significantly affect long-term survival were type of aneurysm repair (resection or plication), morphology of left anterior descending coronary artery (occlusion or stenosis), and size of the aneurysm.     

Biventricular function after myocardial revascularization in humans: deterioration and recovery patterns during the first 24 hours

Critical changes in left and right ventricular function immediately after myocardial revascularization may affect the success of the procedure, morbidity, and mortality. To delineate these changes and identify vulnerable patient populations and times of highest risk, ventricular function was studied for 24 h in 22 patients undergoing myocardial revascularization. Preoperative ejection fractions ranged from 0.26 to 0.81. For each patient, eight left and eight right ventricular function curves (LVFC and RVFC) were generated by altering preload during the 24-h perioperative period. Central venous pressure ranged from 0 to 19 mmHg and pulmonary capillary wedge pressure from 0 to 31 mmHg. In all patients, significant (P less than 0.05) left and right ventricular dysfunction occurred at 15 min following bypass, LVFCs and RVFCs being depressed 35-75% of control. The degree of depression and the pattern of recovery could be predicted best (stepwise logistic regression) by two preoperative indices: the ejection fraction and degree of dyssynergy. Patients with ejection fractions greater than 0.55 and no significant dyssynergy (n = 11) had postbypass LVFCs and RVFCs that were 75% and 60% of control, respectively. However, these depressions were transient, and recovery to 90% of control occurred within 4 h of revascularization. In contrast, patients having preoperative ejection fractions less than 0.45 or dyssynergy (n = 11) had more severely depressed ventricular function (LVFC = 40% and RVFC = 30% of control) that persisted for 24 h after revascularization, resulting in only 60% recovery of ventricular function. In conclusion, the preoperative indices--ejection fraction and degree of dyssynergy--best identified patients most likely to have significant and prolonged biventricular dysfunction after revascularization.     

Revascularization alone (without mitral valve repair) suffices in patients with advanced ischemic cardiomyopathy and mild-to-moderate mitral regurgitation

BACKGROUND: Whether or not to perform adjunctive mitral repair in patients undergoing coronary artery bypass grafting (CABG) for advanced ischemic cardiomyopathy with moderately severe mitral regurgitation (MR) remains controversial. METHODS: We examine the clinical and echocardiographic outcome after isolated CABG in 49 patients with ischemic cardiomyopathy and 1+ to 3+ MR undergoing surgical revascularization. The patients were identified for analysis of mitral valve-related issues from a larger series of 183 patients with ischemic cardiomyopathy (MUGA ejection fraction < or = 30%) undergoing CABG by a single surgeon from 1986 to 1996. Patient age was 66.3 years (mean, range 45 to 83 years). There were 5 women (10.2%) and 44 men (89.8%). Mean ejection fraction was 22.4% with a range of 10% to 30%. Thirty-four patients had preoperative congestive heart failure (70%) and 12 (25%) had pulmonary edema. Number of grafts was 2.8 (mean, range 1 to 5). The MR was 1+ in 18 patients (37.5%), 2+ in 26 (52%) and 3+ in 5 patients (10.5%). RESULTS: Hospital mortality was 2.0% (1 of 49 patients). Ejection fraction improved from 22.0% to 31.5% (p < 0.05) after CABG. Mean degree of MR improved with CABG alone from 1.73 to 0.54 (p < 0.05) as measured at a mean interval of 36.9 months from CABG. New York Heart-Association congestive heart failure class improved from 3.3 to 1.8 (p < 0.05). Long-term survival was 88%, 65%, and 50% at 1, 3, and 5 years postoperatively. No patient required subsequent mitral valve operation or heart transplantation in long-term follow-up. CONCLUSIONS: We conclude that, in patients with advanced ischemic cardiomyopathy and mild-to-moderate MR, isolated CABG (without mitral valve, repair) suffices, producing dramatic improvement in ejection fraction, in congestive heart failure, and in degree of MR, with excellent (relative) long-term survival. The improvement in MR likely results from improved left ventricular function and size consequent upon revascularization.     

Resting gated pool ejection fraction: a poor predictor of perioperative myocardial infarction in patients undergoing vascular surgery for infrainguinal bypass grafting

Ventricular ejection fraction is widely regarded as a prognostic indicator of perioperative myocardial infarction. To evaluate this premise the prevalence of perioperative myocardial infarction or cardiac death was analyzed in relation to preoperative resting gated pool ejection fraction in 85 patients undergoing vascular surgery for infrainguinal bypass grafting. Patients were divided into three groups on the basis of ejection fraction. Group I consisted of 50 patients with ejection fractions of 56% to 92%. Nine (18%) perioperative myocardial infarctions occurred in group I, and there were no cardiac deaths. Group II consisted of 20 patients with ejection fractions of 37% to 55%. Three (15%) myocardial infarctions occurred in this group, and there were no cardiac deaths. Group III included 15 patients with ejection fractions of 20% to 35%. Three (20%) cardiac events occurred in group III including one nonfatal myocardial infarction and two (13%) cardiac deaths. Statistical analysis showed no significant difference in prevalence of cardiac events between any group. These results suggest that resting ejection fraction is a poor predictor of perioperative myocardial infarction in patients undergoing vascular surgery. Patients with normal ejection fractions, but underlying coronary artery disease, are still at significant risk for a perioperative cardiac event.     

Determinants of mid- and long-term results in patients after surgical revascularization for ischemic cardiomyopathy

BACKGROUND: The revascularization of patients suffering from ischemic cardiomyopathy is possible with acceptable perioperative mortality and morbidity. Many publications have discussed the problem of predicting myocardial viability, whereas the quality of the peripheral coronary vessels has been focused on less frequently. METHODS: We studied 908 consecutive patients with ischemic cardiomyopathy revascularized between January 1, 1988 and April 30, 2000. Death, recurrent heart failure, hospitalization due to cardiac causes, ventricular assist device implantation, heart transplantation, and ventricular arrhythmias were defined as adverse events. To analyze the importance of pre- and perioperative variables (state of the coronary arteries, myocardial viability, complete vs incomplete revascularization, urgency of the operation, previous operations, gender, diabetes, preoperative New York Heart Association class, age, number of grafts, and ischemic time), a proportional hazards model was used. RESULTS: The most important predictors of short- and long-term event-free survival were the quality of the coronary arteries, followed by myocardial viability, complete revascularization, number of bypass grafts, and an elective operation. CONCLUSIONS: The coronary vascular system can be described by means of a simple scoring system. A good or at least moderate coronary artery perfusing an area of dysfunctional yet viable myocardium is the main predictor of a successful perioperative course and an event-free survival. Patients with a poor coronary vasculature regardless of myocardial viability should not be considered suitable for revascularization.     

Surgical treatment of ischemic cardiomyopathy: Is it ever too late?

The question posed in the title of this report can be answered both “yes” and “no.” For most patients with severe congestive heart failure due to end-stage ischemic heart disease, however, conventional surgical treatment by myocardial revascularization or unconventional treatment by cardiac transplantation can offer genuine therapeutic benefit by ameliorating symptoms and extending survival. Although the results of standard coronary artery bypass operations in patients with ischemic cardiomyopathy are limited by the magnitude of preexistent left ventricular damage, retrospective analysis of medical and surgical treatment at our institution has shown that most patients with predominant angina pectoris preoperatively can be expected to be alive and free of limiting angina 5 years postoperatively. However, relief of symptoms in patients with predominant congestive heart failure preoperatively was considerably less impressive. Nevertheless, long-term survival rates for surgically treated patients were significantly superior to those for medically treated patients, due possibly to the prevention of fatal myocardial infarction.When the severity of left ventricular dysfunction and clinically evident congestive heart failure preclude a reasonable expectation of benefit from myocardial revascularization, carefully selected candidates with ischemic cardiomyopathy may undergo cardiac transplantation with expectation of survival rates of 59 ± 7 percent at 1 year and 49 ± 7 percent at 3 years, in conjunction with highly satisfactory symptomatic benefit and rehabilitation. Furthermore, the quality of results after cardiac transplantation is highly likely to improve in the near future because of more effective and less toxic immunosuppression. This development should expand the applicability of cardiac transplantation and render even more uncommon the designation of a patient with ischemic cardiomyopathy as inoperable because it is “too late.”     

Placement of intra-aortic balloon pump allows definitive biliary surgery in patients with severe cardiac disease

This study reviews the cases of 15 patients with severe cardiac disease treated with the intra-aortic balloon pump (IABP) to improve cardiac status so that they could undergo definitive cholecystectomy. The 14 men and one woman ranged in age from 49 to 74 years. Indications for cholecystectomy included acute cholecystitis in nine patients and chronic cholecystitis in six patients. All patients had prior myocardial infarction, and in two patients this had occurred within 2 months of operation. All patients were Goldman's Class IV. Eight had severe cardiomyopathy. Mean ventricular ejection fraction was 21% +/- 3%. Cardiac index was 2.2 +/- 0.2 L/m/m2, and pulmonary artery pressure (PAP) was 51 +/- 5/23 +/- 2 mm Hg. After IABP placement, pulmonary wedge pressure decreased in all patients, from 24 +/- 3 mm Hg to 16 +/- 2 mm Hg (p less than 0.01). PAP systolic pressure decreased to 38 +/- 3 mm Hg (p less than 0.01), and PAP diastolic pressure decreased to 18 +/- 2 mm Hg (p less than 0.05). All patients had cholecystectomy. Five patients had intraoperative cholangiography. One of these five patients had a common bile duct exploration, and another underwent cystgastrostomy. Two patients died postoperatively of arrhythmias. Thirteen patients are alive 3 months to 7 years after operation, without biliary symptoms. Three patients have had orthotopic heart transplants. We conclude that IABP significantly improves cardiac performance so that many patients who have severe cardiac disease can undergo definitive biliary surgery.     

Coronary artery bypass grafting in patients with poor ventricular function. Cardiovascular Surgeons of the University of Toronto.

Although patients with severe ventricular dysfunction have improved long-term survival times after coronary bypass procedures, operative morbidity and mortality rates remain high. This study was designed to identify the contemporary risk factors for isolated coronary artery bypass grafting in this high-risk subgroup. Between January 1982 and December 1990, a total of 12,471 patients underwent isolated coronary artery bypass grafting. The 9445 patients with preoperative ejection fractions greater than 40% had a lower operative mortality rate (2.3%) than that of the 2539 patients with ejection fractions between 20% and 40% (4.8%) and that of the 487 patients with ejection fractions less than 20% (9.8%; p less than 0.001). However, patients with ejection fractions of less than 20% were demographically distinct from those with higher ejection fractions. This group was older, with fewer women, a higher frequency of left main stenosis, and more frequent requirement of urgent operation for unstable angina. The risk factors for operative death also varied with preoperative ejection fraction. The traditionally accepted risk factors--urgency of operation, left main coronary artery stenosis, reoperation, sex, and age--were predictive of risk of operative death for patients with ejection fractions greater than 40%. The risk of operative death for patients with ejection fractions between 20% and 40% was predicted by urgency of operation, reoperation, sex, myocardial protection, and age. The only predictor of risk of operative death for patients with ejection fractions less than 20% was urgency of operation. Patients undergoing isolated coronary artery bypass grafting who have severe ventricular dysfunction are therefore a highly selected, high-risk subgroup of patients who risk depends on the urgency of operation. Strategies to improve the results in these patients should be focused on patient selection, improvement of myocardial protection, and more aggressive preoperative treatment of myocardial ischemia.     

Nuclear cardiac ejection fraction and cardiac index in abdominal aortic surgery

Since atherosclerotic heart disease results in more than half of the perioperative deaths that follow abdominal aortic surgery, a prospective protocol was designed for preoperative evaluation and intraoperative hemodynamic monitoring. Twenty men who were prepared to undergo elective operation for aortoiliac occlusive disease (12 patients) and abdominal aortic aneurysm (eight patients) were evaluated with a cardiac scan and right heart catheterization. The night prior to operation, each patient received volume loading with crystalloid based upon ventricular performance curves. At the time of the operation, all patients were anesthetized with narcotics and nitrous oxide, and hemodynamic parameters were recorded throughout the operation. Aortic crossclamping resulted in a marked depression in CI in all patients. CI remained depressed P less than 0.05 after unclamping in the majority of patients. There were two perioperative deaths, both from myocardial infarction or failure. Both patients had ejection fractions less than 30% and initial CIs less than 2 L/M2, while the survivors' mean ejection fraction was 63% +/- 1 and their mean CI was 3.2 L/M2 +/- 0.6. We conclude that preoperative evaluation of ejection fraction can select those patients at a high risk of cardiac death from abdominal aortic operation. These patients should receive intensive preoperative monitoring with enhancement of ventricular performance.     

Myocardial revascularization with combined aortic and mitral valve replacements

Although the results of coronary artery bypass grafting plus single aortic or mitral valve replacement have been documented, the risk of myocardial revascularization with combined aortic and mitral valve replacement is not well defined. We present a series of 33 consecutive patients undergoing myocardial revascularization with combined aortic and mitral valve replacement during a period of almost seven years. There were 21 men and 12 women with a mean age of 67 years. All patients had congestive heart failure, and 21 (64%) had angina pectoris. Mean New York Heart Association functional classification was 3.4; eight patients (24%) had ejection fractions less than 0.40, and 13 patients (41%) had cardiac indices less than 2.0 L/min/m2. All operations were performed with hypothermic crystalloid potassium cardioplegia. The number of coronary arteries grafted varied from one to four (mean, 1.7 grafts per patient). Four patients died while in the hospital (12.1%). There were no perioperative myocardial infarctions. At a follow-up of 2 to 80 months (mean 40.7 months), death had occurred in eight (27.6%) of the 29 hospital survivors. Actuarial survival rate at 72 months was 60.7%. Although no preoperative factors predicted late death, early deaths were related significantly to severe mitral regurgitation, low ejection fraction, high New York Heart Association classification and extensive coronary artery disease (p less than 0.05). Myocardial revascularization with combined aortic and mitral valve replacement can be performed with an acceptable early mortality rate but with an appreciable late mortality rate.     

The preoperative and intraoperative hemodynamic predictors of postoperative myocardial infarction or ischemia in patients undergoing noncardiac surgery.

Among hypertensive and diabetic patients undergoing elective noncardiac surgery, preoperative status and intraoperative changes in mean arterial pressure (MAP) were evaluated as predictors of postoperative ischemic complications. Of 254 patients evaluated before operation and monitored during operation, 30 (12%) had postoperative cardiac death, ischemia, or infarction. Twenty-four per cent of patients with a previous myocardial infarction or cardiomegaly had an ischemic postoperative cardiac complication. Only 7% of those without either of these conditions sustained an ischemic complication. No other preoperative characteristics, including the presence of angina, predicted ischemic cardiac risk. Nineteen per cent of patients who had 20 mm Hg or more intraoperative decreases in MAP lasting 60 minutes or more had ischemic cardiac complications. Patients who had more than 20 mm Hg decreases in MAP lasting 5 to 59 minutes and more than 20 mm Hg increases lasting 15 minutes or more also had increased complications (p less than 0.03). Changes in pulse were not independent predictors of complications and the use of the rate-pressure product did not improve prediction based on MAP alone. In conclusion patients with a previous infarction or radiographic cardiomegaly are at high risk for postoperative ischemic complications. Prolonged intraoperative increases or decreases of 20 mm or more in MAP also resulted in a significant increase in these potentially life-threatening surgical complications.     

Effects of coronary revascularization on infarcted myocardial regions--evaluation on postoperative left ventricular regional wall motion during exercise

In order to determine the effects of coronary revascularization for infarcted regions on postoperative left ventricular function and regional wall motion, we studied first-pass radionuclide angiography at rest and during exercise before and after operation in 18 patients with previous myocardial infarction. Preoperative mean value of left ventricular ejection fraction (LVEF) was significantly decreased during exercise from 56.8 +/- 14.1% to 46.1 +/- 15.5% (p less than 0.01). Postoperatively, there was no change of the values between at rest and during exercise: 53.6 +/- 14.1% versus 51.9 +/- 15.7%. Postoperative mean LVEF during exercise was significantly higher, compared with that of preoperative LVEF (p less than 0.05). Mean regional ejection fraction of infarcted regions was significantly decreased during exercise from 66.0 +/- 15.0% to 56.1 +/- 15.8% (p less than 0.01) before operation. However, there was no significant change in values between at rest and during exercise after operation: 65.4 +/- 13.9% versus 61.8 +/- 14.5%. Mean postoperative regional ejection fraction during exercise was significantly higher, compared with preoperative regional ejection fraction after operation (p less than 0.05). These results might be indicated that regional wall motion of the infarcted regions with ischemia enhanced by exercise preoperatively can be definitely improved by coronary revascularization.     

A comparison of nitroglycerin and nitroprusside: I. Treatment of postoperative hypertension

Nitroglycerin improves perfusion to ischemic myocardial regions and therefore has theoretical advantages over sodium nitroprusside to treat hypertension (mean arterial pressure [MAP] greater than 95 mm Hg) following coronary bypass operation. Thirty-three hypertensive patients were randomized to an initial infusion of either nitroglycerin or nitroprusside in a crossover trial designed to reduce MAP to 85 mm Hg. Thermodilution cardiac output measurements permitted calculation of left ventricular stroke work index (LVSWI), and nuclear ventriculograms permitted estimation of left ventricular ejection fraction, left ventricular end-diastolic volume index (LVEDVI), and left ventricular end-systolic volume index (LVESVI). Coronary sinus blood flow was measured by the continuous thermodilution technique, and arterial and coronary sinus lactate measurements permitted calculation of myocardial lactate flux (MVL). Both nitroglycerin and nitroprusside reduced MAP (-25 +/- 12 mm Hg and -20 +/- 10 mm Hg, respectively; not significant [NS]). Nitroglycerin reduced LVSWI more than did nitroprusside (-15 +/- 13 gm-m/m2 and -7 +/- 9 gm-m/m2, respectively; p less than 0.01). Both agents increased left ventricular ejection fraction (nitroglycerin, +8 +/- 8%, and nitroprusside, +10 +/- 7%; NS), and decreased LVEDVI (-20 +/- 22 ml/m2 and -11 +/- 17 ml/m2, respectively; NS) and LVESVI (-13 +/- 14 ml/m2 and -10 +/- 12 ml/m2, respectively; NS). Coronary sinus blood flow decreased with both drugs (NS), but MVL increased with nitroglycerin (+0.02 +/- 0.14 mmol/min) and decreased with nitroprusside (-0.02 +/- 0.02 mmol/min) (p less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)