Valvular heart disease. A comparative study of results after primary operation, reoperation, and after multiple reoperation.

Reoperation for valvular heart disease has been associated with a higher operative mortality than primary operations, especially in patients who had multiple prior operations. We have analyzed the 226 consecutive patients who underwent valve replacement. These involved 163 primary operations, 52 first reoperation, and 11 second/third reoperations. Preoperative left ventricular dysfunction was more severe, and operation time and cardiopulmonary bypass time were significantly greater according to the number of operations, associated with a greater amount of intraoperative blood loss. The operative mortality after a second/third reoperation was 27.3%, which was significantly higher than that after primary operation (6.7%) (p < 0.05), and that after first reoperation (5.8%) (p < 0.05). Seven (64%) patients who underwent a second/third reoperation had poor preoperative left ventricular function (%FS < 25%), and 5 (71%) of these required postoperative mechanical supports, and 3 (60%) of the 5 patients died of low output syndrome. We have found that poor preoperative left ventricular function and the duration on cardiopulmonary bypass, but not the number of reoperation were correlated with operative mortality. Continued efforts should be directed to decrease the mortality for multiple reoperative valve surgery.     

Is the use of cardiopulmonary bypass for multivessel coronary artery bypass surgery an independent predictor of operative mortality in patients with ischemic left ventricular dysfunction?

BACKGROUND:l Coronary artery bypass grafting for patients with ischemic left ventricular dysfunction (ILVD) remains superior to medical therapy in terms of long-term survival. Recently, off-pump coronary artery bypass surgery has been shown to be very promising in achieving functional improvements with favorable operative mortality in this challenging group of patients. The aim of this study was to assess the risk factors responsible for operative mortality in this group of patients. METHODS: The records of 305 consecutive ILVD patients, who underwent primary isolated coronary artery bypass grafting for multivessel disease at The National Heart and Lung Institute, Imperial College, University of London, between January 1999 and January 2002, were reviewed retrospectively. Patients were considered to have ILVD if they had a left ventricular ejection fraction of 0.30 or less on preoperative coronary angiography. One hundred six patients were operated on using the off-pump coronary artery bypass surgery technique, and 199 patients were operated on using the conventional coronary artery bypass grafting technique with cardiopulmonary bypass. RESU;TS: Seven (6.6%) patients died in the off-pump coronary artery bypass surgery group, whereas 28 (14.1%) patients died in the cardiopulmonary bypass group (p = 0.05). Univariate analysis of all the preoperative characteristics was performed to identify the potential predictors of mortality in the whole group of ILVD patients. Potential predictors of mortality included symptom status (stable/unstable), chronic obstructive airway disease, dyspnea grade III and IV on the New York Heart Association classification, intravenous nitrates, preoperative use of intraaortic balloon pump, ventricular tachycardia or ventricular fibrillation, body surface area less than 2, and cardiopulmonary bypass. Only ventricular tachycardia or ventricular fibrillation was proved to act as an independent predictor of operative mortality in this group of ILVD patients, with an odds ratio of 29.6 (95% confidence interval, 8.9 to 98). CONCLUSIONS: This study showed that using cardiopulmonary bypass for multivessel coronary artery bypass grafting in patients with ILVD was not proved to act as an independent predictor of operative mortality.     

Applicability of noncardioplegic coronary bypass to high-risk patients. Selection of patients, technique, and clinical experience in 3000 patients.

Although some surgeons still prefer noncardioplegic coronary bypass, most surgeons are skeptical of its suitability for high-risk patients. We analyzed the first 3000 patients who had primary coronary bypass without cardioplegia since our program's inception. Patients with reoperations, valve operations, or carotid endarterectomies were excluded. Multivariate predictors of operative death included age, sex, left ventricular dysfunction, preoperative intraaortic balloon pumping, and urgency of operation. Eight hundred seventy-nine patients (29%) were more than 70 years of age; 795 (27%) were female; 290 (9.7%) had an ejection fraction less than 0.30, and another 77 (2.6%) had left ventricular aneurysms; 196 (6.5%) had an acute myocardial infarction, and another 397 (13%) had a myocardial infarction less than 1 week preoperatively; 917 (31%) had rest pain in the hospital (preinfarction angina). Only 790 (26%) had elective operations. The overall operative mortality rate was 1.47% (44/3000): The mortality rate for elective operations was 0.5% (4/790); urgent 1.7% (28/1687); emergency 2.3% (12/523). In patients with an ejection fraction less than 0.30 the mortality rate was 6.2% (18/290); with age more than 70 years, it was 3.9% (34 of 879); with acute myocardial infarction it was 3.1% (6/196); and with left ventricular aneurysmectomy it was 1.3% (1/77). Inotropic support after leaving the operating room was needed in 6.6% (199 patients), and 1% (30 patients) required new intraaortic balloon pumping postoperatively (two of these 30 patients died). These results provide reassurance that noncardioplegic coronary artery bypass grafting provides excellent myocardial protection and operating conditions for primary coronary bypass and is particularly suitable for high-risk patients.     

Reoperations for valve surgery: perioperative mortality and determinants of risk for 1,000 patients, 1958-1984

One thousand consecutive cardiac reoperations for valve surgery in 897 patients were reviewed to determine in-hospital mortality and indicators of risk. Subgroups based on the number of previous cardiac procedures and the valve or valves replaced or repaired at reoperation (aortic valve, mitral valve, tricuspid valve, or multiple valves and mortality [deaths/number of procedures (% mortality)]) for those subgroups are as follows: (Table: see text) Predictors of increased risk for a first aortic valve reoperation were advanced age (p = .0002), endocarditis (p = .0018), female sex (p = .014), impaired left ventricular function (p = .039), and number of coronary vessels obstructed by 70% or more (p = .055). For a first mitral valve reoperation, the predictors were advanced age (p less than .0001), preoperative shock or cardiac arrest (p = .01), previous aortic or tricuspid valve operations (p = .02), type of mitral valve procedure (risk for repair of periprosthetic leak was greater than mitral valve replacement which was greater than mitral valve-conserving operation [p = .05]), and impaired left ventricular function (p = .059). For a first multiple valve reoperation, the predictors were diabetes (p = .04) and ascites (p = .02), whereas patients undergoing mitral valve replacement and tricuspid valve operations were at decreased risk (p = .01). Comparison of second reoperations with first reoperations indicates risk increases for multiple operations (p = .01) but not for aortic or mitral valve procedures. Rereplacement of a prosthesis (p = .007), coronary bypass grafting at reoperation (p = .006), and advanced age (p = .06) increased the risk for second reoperations. Age is the most consistent predictor of risk for patients undergoing valve reoperations.     

Risk factors and outcomes after coronary reoperation in 739 elderly patients

BACKGROUND: As second coronary artery bypass graft (CABG) operations are becoming more common in elderly patients, we conducted a retrospective analysis of risk factors for in-hospital and late outcome in patients aged 70 and over. METHODS: We reviewed records of 739 patients who underwent second CABG at age 70 or older at our institution between 1983 and 1993. Preoperative, operative, and postoperative variables were analyzed to identify predictors of in-hospital and long-term mortality. RESULTS: The mean age (+/- standard deviation) at reoperation was 74 +/- 3 years and the mean interval after primary operation was 130 +/- 55 months. In-hospital mortality was 7.6% (n = 56). Preoperative factors associated with increased in-hospital mortality were preoperative creatinine greater than 1.6 mg/dL (p < 0.001), emergency operation (p < 0.001), female sex (p = 0.012), moderate or severe left ventricular dysfunction (p = 0.049), and left main coronary disease (p = 0.045). In-hospital, actuarial survival was 75% at 5 years and 49% at 10 years. Cardiac event-free survival was 60% at 5 years and 27% at 10 years. The factors independently associated with increased late death were hematocrit (p = 0.046), diabetes (p = 0.011), peripheral vascular disease (p < 0.001), left ventricular function (p < 0.001), history of cancer (p = 0.016), preoperative nonsinus rhythm (p = 0.003), anticoagulation or antiplatelet therapy (p = 0.018), postoperative encephalopathy (p = 0.001), and postoperative stroke (p = 0.014). CONCLUSIONS: CABG reoperation can have excellent results for many elderly patients, but mortality is markedly higher when elderly patients have certain risk factors and comorbidities, alone or in combination. This information should be helpful in educating patients before they decide whether to choose reoperation.     

Repeat heart valve surgery: risk factors for operative mortality.

BACKGROUND: Patients undergoing repeat heart valve operations are a diverse population. We assessed risk factors for operative mortality in patients undergoing a first heart valve reoperation. METHODS: A retrospective review of hospital records was performed for 671 patients who underwent first repeat heart valve operations between 1969 and 1998. Univariable and multivariable analyses were performed. RESULTS: Operative mortality was 8.6%. Mortality fell each decade to 4.8% in the most recent period (adjusted chi(2) for linear trend P <.0005). Mortality increased from 3.0% for reoperation for a failed repair or reoperation at a new valve site to 10.6% for prosthetic valve dysfunction or periprosthetic leak and to 29.4% for endocarditis or valve thrombosis. Concomitant coronary artery bypass grafting was associated with a mortality of 15.4% compared with 8.2% when it was not required. Mortality for aortic valve replacement was 6.4%, mitral valve replacement 7.4%, aortic and mitral valve replacement 11.5%, tricuspid valve replacement 25.6%, periprosthetic leak repair 9.1%, and isolated valve repair 2.2%. Among 336 patients requiring replacement of prosthetic valves, mortality was 26.1% for replacement of a mechanical valve compared with 8.6% for replacement of a tissue valve (P <.0005). Multivariable analyses identified year of reoperation, age, coronary artery bypass grafting, indication, and replacement of a mechanical valve rather than a tissue valve as significant explanatory variables for operative mortality. CONCLUSIONS: Heart valve reoperations can be performed with an acceptable operative mortality. However, we have identified several categories of patients in whom reoperation carries an increased risk.     

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.     

Sudden Development of Intraoperative Left Ventricular Outflow Obstruction: Differential and Mechanism. An Intraoperative Two-Dimensional Echocardiographic Study

Systolic anterior motion (SAM) of the mitral valve, once considered to be pathognomonic of hypertrophic cardiomyopathy, has been reported in the absence of asymmetric septal hypertrophy. Of the 1,000 open heart operations performed with intraoperative two-dimensional epicardial echocardiography monitoring, four patients developed intraoperative dynamic left ventricular outflow obstruction associated with systolic anterior motion of the mitral valve that was not present preoperatively: three cases of mitral valve annuloplasty with Carpentier ring insertion and one of coronary artery bypass grafting. Though no patient had asymmetric septal hypertrophy or echocardiographic evidence of outflow obstruction by either preoperative cardiac catheterization or echocardiography, intraoperative two-dimensional epicardial echocardiography revealed SAM, and hyperdynamic left ventricles with three of these patients having documented left ventricular outflow tract gradients causing hemodynamic compromise. (Case 4 was hemodynamically stable following mitral valve repair, but had SAM and significant residual mitral regurgitation [MR] requiring reinstitution of cardiopulmonary bypass and re-repair). Measurement of mitral annular dimension demonstrated a normal decrease in size from diastole to systole in control operative subjects but not in the patients who developed outflow obstruction. The pathophysiology, treatment, and role of intraoperative echocardiography of dynamic left ventricular outflow tract obstruction are discussed.     

Surgical repair of tetralogy of Fallot. Long-term follow-up with particular emphasis on late death and reoperation

Early and late results in 309 patients undergoing repair of tetralogy of Fallot between 1960 and 1982 were analyzed with respect to independent determinants of operative mortality, late reoperation, and late death. Follow-up extended to 22 years and totaled 2,743 patient-years. The operative mortality rate was 4.9% +/- 1.3%. Multivariate logistic regression analysis revealed that only young age, long cardiopulmonary bypass time, and (probably) extent of right ventricular outflow tract patch were independent significant determinants of operative mortality. Patients who required a transannular right ventricular outflow tract patch and those who underwent repair without any outflow tract patch were at higher risk than those who received a separate right ventricular and/or pulmonary artery patch. The long-term results were highly satisfactory: Only 15% +/- 3% of patients required reoperation 13 years postoperatively, and 85% +/- 4% of discharged patients were alive 16 years later. Time-dependent linear stepwise multivariate discriminant analysis showed that extent of right ventricular outflow tract patch (transannular greater than none greater than right ventricular and/or [separate] pulmonary arterial), longer ischemic arrest time, previous palliative shunt, and primary suture closure of the ventricular septal defect were the only covariates that independently portended a higher likelihood of reoperation. Similarly, only older age, absence of hypoxic spells, and reoperation were significantly and independently related to the probability of late death. The results of these analyses demonstrate that intracardiac repair of tetralogy is a durable procedure for upwards of 20 years; however, high-risk subsets of patients can be identified in terms of operative mortality, reoperation, and late death. Thus, there is still a need for improvement, particularly future research devoted to better understanding of the electrophysiological mechanisms responsible for arrhythmias, electrosurgical and medical arrhythmia therapy, and right and left ventricular mechanics after repair of tetralogy of Fallot.     

Determinants of operative mortality following primary coronary artery bypass surgery.

BACKGROUND: The purpose of this study was to determine the factors which can help to predict operative mortality before performing the operation, and afterwards. METHODS: The study population consisted of 504 patients (91 women and 413 men) who underwent primary isolated coronary artery bypass surgery from December 1997 to September 1999 by the same surgeon in a referral center in Tehran, Iran. Perioperative data were gathered and analyzed both in a univariate and multivariate model. RESULTS: After the operation patients spent 7.3 +/- 4.0 days in hospital. The total operative morbidity was 20.5%. Arrhythmias were the most common complication, with atrial fibrillation as the predominant feature. Major complications of the operation were: low cardiac output (4.2%); prolonged ventilatory support (2.4%); hemorrhage and exploratory reoperation (2.0%); postoperative myocardial infarction (1.4%); postoperative renal failure in (1.4%); and postoperative cerebrovascular accident (0.8%). Operative mortality rate in this study was 2.98%. Factors associated with high operative mortality in univariate analysis were: recent myocardial infarction, low ejection fraction, non-elective operation, left main coronary artery disease and prolonged cardiopulmonary bypass time. CONCLUSION: Our data suggest that prior to operation, operative mortality can be best predicted by urgency of operation and left ventricle ejection fraction. After performing the operation, prognostic factors include preoperative LVEF < or = 35%, non-elective operation, and prolonged cardiopulmonary bypass time. Further study is required to assess the generalization of our findings to Iranian patients.     

Continuous retrograde blood cardioplegia is associated with lower hospital mortality after heart valve surgery

OBJECTIVE: Myocardial preservation studies comparing blood and crystalloid cardioplegia techniques were almost exclusively performed on patients undergoing coronary bypass, and they were unable to show a difference in hospital mortality. We investigated possible factors, including cardioplegia techniques, influencing hospital mortality in patients undergoing cardiac valve surgery. METHODS: We evaluated hospital mortality in 1098 consecutive patients undergoing cardiac valve surgery by using a multivariate logistic regression with propensity score balancing of the groups. In 25% of the patients, multiple valve or Bentall procedures were performed, and in 46% of all patients, coronary bypass grafting was associated with valve surgery. A first cohort of 504 consecutive patients were operated on by using single-shot antegrade cold crystalloid cardioplegia, and a second cohort of 594 patients were operated on by using continuous retrograde cold blood cardioplegia. RESULTS: After correction for patient-related and operative risk factors, lower hospital mortality was found in patients who received retrograde blood cardioplegia (P =.020). The odds ratio of in-hospital death when using blood cardioplegia was 0.44 (95% confidence interval, 0.22-0.88). Further predictors of hospital mortality were age, advanced New York Heart Association functional class, cardiopulmonary bypass time, reoperation, active endocarditis, and renal failure. CONCLUSIONS: This study shows that continuous retrograde blood cardioplegia is associated with lower hospital mortality in heart valve operations.     

Replacement of the ascending aorta. Early and late results

From 1978 through 1987, 225 patients underwent operations that included replacement of the ascending aorta. One hundred twenty-three patients underwent composite aortic valve and ascending aortic replacement, 30 had aortic valve replacement with separate graft replacement of the ascending aorta, and 72 underwent replacement of the ascending aorta without aortic valve replacement. Thirty-one (13.8%) in-hospital deaths occurred. Univariate testing of preoperative and operative variables followed by logistic regression analyses identified miscellaneous aortic disease, coronary artery bypass grafting, aortic arch replacement, emergency operation, surgical date (1978 to 1983), and age (all p less than 0.05) as factors having independent association with in-hospital mortality. Follow-up of in-hospital survivors (mean interval 46 months, range 8 to 123 months) documented an overall 5-year survival rate of 76%, 83% after primary operation and 37% after reoperation. Univariate analyses followed by multivariate testing indicated that previous operation (p less than 0.0001) and a history of preoperative neurologic symptoms (p = 0.021) were associated with decreased late survival. At follow-up 88% of late survivors were free of symptoms. Seven patients have undergone reoperation 1 day to 69 months postoperatively. Although the in-hospital mortality for operations that include ascending aortic replacement exceeds that for isolated aortic valve replacement, the late death rate and rate of reoperation are low.     

Central nervous system damage following surgery using cardiopulmonary bypass—A retrospective analysis of 1386 cases

In order to determine the incidence and risk of central nervous system damage (CNSD) which accompanies cardiovascular surgery, a retrospective analysis was carried out on 1386 patients who received surgery utilizing cardiopulmonary bypass. CNSD occurred in 32 of the 1386 patients, the total incidence being 2.3 per cent. The major risk factors which led to a high incidence of CNSD were found to be reoperation, thrombus in the left atrium (TLA) and calcification of the ascending aorta (Cal aAo). In the primary surgical series, CNSD was found in only 29 of 1350 patients (2.2 per cent), however, of a total 36 patients who underwent reoperation, 3 (8.3 per cent) patients developed CNSD (p<0.05). In a surgical series done on 562 patients with mitral valve disease, the prevalence of CNSD was much higher in patients who suffered TLA than in those who did not, being 4/85 cases (4.7 per cent)vs 11/477 cases (2.3 per cent), respectively. Moreover, a significantly higher incidence of CNSD was noted in patients with Cal aAo, occurring in 6/10 cases (60 per cent) with Cal aAovs 4/333 cases (1.2 per cent) without Cal aAo (p<0.001). The results of this study showed that patients with CNSD, who had received coronary artery bypass surgery and aortic arch replacement tended to follow a poor clinical course, suggesting that atheromatous plaque embolization may be the leading cause of the poor prognosis following CNSD in patients having undergone cardiopulmonary bypass.     

Operative Treatment of Congenital Aortic Stenosis

The operative treatment of 131 patients with congenital aortic stenosis is reviewed. Of the 131 patients, 77% had left ventricular outflow tract (LVOT) obstruction at a single level and 23%, major obstruction at more than one level. There were 3 operative deaths (2.3%) and 10 late deaths (7.8%).Twenty of the 128 discharged patients have undergone a second procedure and 6 a third procedure for recurrent or residual LVOT obstruction. The 26 reoperations included 7 aortic valve replacements, 4 left ventricular apical-abdominal aortic (LV-AA) valved conduits, and 15 extensive aortic valvotomies with or without supravalvular aortoplasty. Five of the 20 patients undergoing reoperation died; 4 of these deaths occurred in patients who had valve replacement at reoperation. The 4 who received LV-AA conduits have sustained excellent hemodynamic and clinical results with no complications.Highly satisfactory clinical results can be obtained with minimal operative risk, regardless of the level of LVOT obstruction. Reoperation for recurrent or residual LVOT obstruction, however, is comparatively more hazardous, and alternative surgical approaches (LV-AA conduits) should be considered.     

Aggressive preoperative use of intraaortic balloon pump in elderly patients undergoing coronary artery bypass grafting

BACKGROUND: The use of the intraaortic balloon pump (IABP) in patients undergoing coronary artery bypass grafting has been traditionally associated with a high complication rate and adverse outcomes. However, recent reports show that many of these catastrophic outcomes can be avoided by preoperatively placing the IABP in high-risk patients. To further validate these reports, we defined a set of liberal criteria for preoperative IABP insertion and applied them to a series of elderly patients (70 years or older) undergoing isolated coronary artery bypass grafting. METHODS: Two hundred six consecutive patients who underwent isolated coronary artery bypass grafting with cardiopulmonary bypass were retrospectively reviewed. A rapid recovery protocol emphasizing reduced cardiopulmonary bypass time, an anesthetic protocol for early extubation, perioperative administration of corticosteroids and thyroid hormone, and aggressive diuresis was applied to all patients. Patients who required an urgent operation because of failed percutaneous transluminal coronary angioplasty, a critical left main stenosis (70% or greater), pronounced left ventricular dysfunction (left ventricular ejection fraction 40% or less), or unstable angina refractory to medical therapy or who required an emergency reoperation received preoperative IABP support. RESULTS: The 30-day mortality rate for the entire group was 4.4%. There were 97 patients (47%) who received a preoperative IABP (group II) in comparison with 109 patients (53%) who did not fulfill the preoperative insertion criteria (group I). Patients in group II had a lower left ventricular ejection fraction (mean, 46% versus 59%, p<0.001) and a higher incidence of congestive heart failure (35% versus 17%, p<0.01) and acute myocardial infarction (37% versus 17%, p<0.01) than patients in group I. The average postoperative hospital length of stay for patients in group II was slightly longer than for those in group I (9.0+/-10.5 versus 6.0+/-3.7 days, p<0.01). However, there were no statistically significant differences in complication or mortality rates between the two groups. Only 2 patients (2.2%) had complications related to IABP insertion. Lower extremity ischemia occurred in both patients, and both were treated successfully with thromboembolectomy. CONCLUSIONS: Liberal preoperative insertion of the IABP can be performed safely in high-risk elderly patients undergoing coronary artery bypass grafting, with results comparable to those in lower risk patients.     

Left ventricular function and coronary obstruction as predictors of survival following aorta-coronary bypass.

A retrospective analysis was undertaken of clinical data and catheterization studies of 151 consecutive unselected patients who underwent aorta-coronary bypass at the University of Kansas Medical Center between 1971 and 1973. The purpose was to determine the effect of preoperative left ventricular function and extent and severity of coronary artery obstruction on operative mortality rate and long-term survival. The postoperative follow-up period ranged from 10 to 49 months and averaged 26 months. Left ventricular function was assessed by qualitative analysis of left ventricular angiograms. Severity of coronary obstruction was quantified by scoring coronary arteriograms according to the system of Friesinger and associates. Patients with normal or near normal ventriculograms were considered to have good left ventricular function. Patients showing moderate or severe impairment of contraction were considered to have poor left ventricular function. Obstruction scores ranging from 2 to 7 points were classified as low scores, and scores from 8 to 15 points were classified as high scores. Four groups of patients were identified based upon preoperative left ventricular function and obstruction severity: Group I, 29 patients with good left ventricular function and low scores; Group II, 22 patients with poor left ventricular function and low scores. Group III, 28 patients with good left ventricular function and high scores. Elective aorta-coronary bypass in these three groups was accompanied by no operative or late deaths. Group IV comprised 72 patients with poor left ventricular function and high scores. In this group there was a 10 per cent operative mortality rate (7 of 72 patients) and a 5 per cent year late mortality rate. Relief of angina occurred equally in all groups. Thus operative risk can be prospectively determined by analysis of left ventricular function and severity of coronary obstruction. Surgical treatment resulted in negligible operative and late mortality rates (0 per cent) in all patients except those in whom poor ventricular function was accompanied by severe and diffuse coronary artery obstruction. Operation should be offered to this latter group (Group IV) despite the higher operative and postoperative risk because of salutary postoperative results.     

Considerations in determining indication for valvular surgery

Between 1970 and 1987 valvular operations with cardiopulmonary bypass were performed on 636 patients, with an overall early mortality of 7.5%. To determine the critical indication for valvular surgery, preoperative clinical characteristics were examined by comparing 35 patients, who had died of surgery because of low cardiac output syndrome or multiple organ failure, with operative survivors. The multivariable logistic analyses demonstrated that NYHA functional class IV, multiple valvular disease, large CTR more than 70%, high left ventricular end-diastolic pressure more than 15 mmHg, depressed left ventricular ejection fraction less than 40%, and renal and hepatic dysfunction were powerful independent clinical characteristics concerning operative mortality. The mortality was highly significant when a patient was associated with more than three of the above factors in addition to being NYHA class IV. It should be emphasized, however, that there are three survivors among 11 patients with all six factors. On the other hand the prognosis of such patients without surgery was very poor, fifteen of 21 patients, medically treated during the same period, died within two years after reaching NYHA class IV condition. These results show that several predictors are useful for decision making regarding the indication for valvular surgery. Surgery, however, should not be denied because of the severity of the disease.     

Adult respiratory distress syndrome after cardiac surgery

Adult respiratory distress syndrome, characterized by high permeability pulmonary oedema caused by endothelial cell damage, resulting in refractory hypoxemia, has a very high mortality. Cardiopulmonary bypass is said to be responsible for the development of adult respiratory distress syndrome after cardiac surgery. The present study was performed in order to identify predicting and aetiological factors of adult respiratory distress syndrome and multiple organ failure after cardiac surgery. Between January 1984 and December 1993, 3848 patients underwent cardiac surgery with cardiopulmonary bypass in the authors' institution, and were analysed in a retrospective manner. The operations performed were 3444 coronary artery bypass grafts (CABG), 267 valve and 137 combined (CABG + valve) procedures. The incidence of adult respiratory distress syndrome was 1.0% (38 of 3848) with an overall mortality rate of 68.4% (26 patients); 24 of these died from multiple organ failure. Multivariate regression analysis identified hypertension, current smoking, emergency surgery, preoperative New York Heart Association (NYHA) class 3 and 4, low postoperative cardiac output and left ventricular ejection fraction < 40% as significant, independent predictors for adult respiratory distress syndrome. Combined cardiac surgery and diffuse coronary disease were also significant predictors; cardiopulmonary bypass time was not. Thirty-six of the 38 patients that later developed adult respiratory distress syndrome had low postoperative cardiac output, 12 requiring intra-aortic balloon pump support. The remaining two had severe hypotension caused by postoperative bleeding. Twenty-six adult respiratory distress syndrome patients (68%) had confirmed gastrointestinal complications (e.g. intestinal ischaemia). Adult repiratory distress syndrome is a rare complication after cardiac surgery but is associated with a very high mortality. Preoperative predictors were identified. Cardiopulmonary bypass alone was not found to be an important factor. Postoperative low cardiac output leading to splanchnic hypoperfusion may be the most important single factor in developing adult respiratory distress syndrome after cardiac surgery.     

Liberal use of tricuspid valve detachment for transatrial ventricular septal defect closure

BACKGROUND: Although temporary tricuspid valve detachment is useful for improved visualization of ventricular septal defect through right atriotomy, liberal use of this adjunct is not widely supported, mainly because of concerns about iatrogenic complications such as heart blocks and tricuspid valve dysfunction. The objective of this study was to determine whether liberal use of this adjunct can improve operative outcome. METHODS: Between January 1997 and March 2002, trans-atrial closure of isolated ventricular septal defect (conoventricular or canal type) was performed in 87 consecutive patients. Tricuspid valve detachment was used in 4 out of 44 patients (prudent-use group) and 19 out of 43 patients (liberal-use group) in the first and second half of this period, respectively (p = 0.0002). Patient demographics and use of other surgical and cardiopulmonary bypass techniques remained virtually unchanged during this period. RESULTS: In the prudent-use group, there was one operative death with prolonged bypass time and one residual defect that required reoperation; neither of these patients underwent tricuspid valve detachment. All other patients (both groups) were free from mortality and clinically significant complications, including heart block, tricuspid regurgitation, and residual defect. The liberal-use group had shorter cardiopulmonary bypass time than the prudent-use group (59 +/- 14 vs 67 +/- 22 minutes, p = 0.037). CONCLUSIONS: Tricuspid valve detachment should be used liberally for moderate- or even low-difficulty exposure of ventricular septal defect, regardless of patient background, because it is a safe and effective adjunct that can improve speed, programmability, reproducibility, and reliability.     

Surgical management of left ventricular outflow tract obstruction in a specialized hypertrophic obstructive cardiomyopathy center

ObjectivesThis study evaluates operative approach and contemporary surgical outcomes in the management of left ventricular outflow tract obstruction by a single surgeon at a high-volume, specialized hypertrophic cardiomyopathy center.MethodsThis is a retrospective review of 1559 consecutive operations for left ventricular outflow tract obstruction from 2005 to 2015. Demographic profiles, echocardiogram-derived ventricular morphology and hemodynamics, operative data, and in-hospital outcomes were analyzed.ResultsOf the 1559 operations, 586 were isolated septal myectomies, 522 were myectomies with mitral valve or subvalvular apparatus intervention, 422 were myectomies with another concomitant procedure, and 29 were isolated mitral valve interventions without myectomy. Common mitral valve interventions included anterior leaflet shortening (16%), chordae tendineae resection (9.8%), papillary muscle resection (7.2%), and papillary muscle reorientation (7.5%). Ninety-two patients underwent mitral valve replacement, 42 for left ventricular outflow tract obstruction and 50 for intrinsic mitral valve pathology. Patients undergoing mitral interventions had thinner septums (18 ± 0.4 mm vs 22 ± 0.5 mm, P < .001) and less myocardium removed (6.2 ± 3.5 g vs 8.8 ± 3.8 g, P < .001) than patients without a mitral intervention. Prevalence of in-hospital permanent pacemaker insertion was 4.2% (n = 1334) for complete heart block and 1.1% (n = 464) for isolated septal myectomy with normal preoperative conduction. Overall, there were 2 postoperative ventricular septal defects (0.13%) and none for isolated myectomies. Operative mortality was 0.38%.ConclusionsSeptal myectomy can be performed safely with excellent outcomes when the procedure is performed by a highly experienced surgeon in a high-volume, specialized center. A mitral valve intervention is a useful adjunct in patients with moderate hypertrophy.